AU605340B2

AU605340B2 - A process for the manufacture of novel unsaturated amino acid compounds

Info

Publication number: AU605340B2
Application number: AU20389/88A
Authority: AU
Inventors: Hans Allgeier; Christof Angst; Guido Bold; Rudolf Duthaler; Roland Heckendorn; Antonio Togni
Original assignee: Ciba Geigy AG
Current assignee: Novartis AG
Priority date: 1987-08-04
Filing date: 1988-08-03
Publication date: 1991-01-10
Anticipated expiration: 2008-08-03
Also published as: DK434788D0; EP0302826A3; JP2714018B2; YU150188A; FI883589A0; NZ225649A; JPH1053597A; IL87246A; CA1328113C; DD282016A5; NO172495C; FI94415C; PT88170B; JPH0248586A; DK434788A; EP0302826A2; PH27591A; NO883444L; ZA885653B; HUT47947A

Description

Farm COMMONWEALTH OF AUSTRALIA PATENTS ACT 1952-69 COMPLETE SPECIFICATION

(ORIGINAL)

Application Number:0o 5s 4IntCls Lodged: Complete Specif icatioh Lodged; Accepted: Published: t t t This dcuiment contains the amendments made urid,.r Section 49 and is correct fur pin nt ing, N, Iame of Applicant; tAddress of Applictint M'tual Inventor: Address for Service: CIBA-GEIGY AG Klybeckstrasse 141, 4002 Basle, Switzerland HANS ALLGEIER, CHRISTOF ANGST, GUIDO BOLD-, RUDOLF DUTHALER ROLAND HECKENDORN and ANTONIO TOGNI

XDD-ATE

-6-UR----,ET--LORE AUSTRALIA,-3000- Complete Specification for the invention entitled: A PROCESS FOR TH-E MANUFACTURE OF NOVEL UNSATURATED AMINO ACID COMPOUNDS The following statement is a full description of this invention, Including the best method at performing it known to ;us i i 1< 4-16618/+ A process for the manufacture of novel unsaturated amino acid compounds The invention relates to a process for the manufacture of unsaturated amino acid compounds of formula T 3 4~--R a oo n 1 2 in which Ri is hydrogen, alkyl or hydroxy, Rz is hydrogen, alkyl, haloo *6 lower alkyl, hydroxy-lower alkyl, lower alkoxy-lower alkyl, aryl-lower alkyl, lower alkenyl, halogen or aryl, R3 is hydrogen, alkyl or aryl, R| S is hydrogen or alkyl, R 5 is unsubstituted carboxy or esterified or amidated carboxy, R6 is an amino group that is unsubstituted or substituted by lower alkyl or by aryl-lower alkyl, A is unsubstituted or alkyl-substituted a,w-alkylene having from 1 to 3 carbon atoms (C-atoms) or is a direct bond, and B is methylene or a bond, with the proviso that 9 9 A is unsubstituted or alkyl-substituted c,w-alkylene having from 1 to 3 C-atoms when B is a direct bond, and of the salts thereof, also to (2R)-E-2-amino-4-methyl-5-phosphono-3-pentenoic acid ethyl ester as such.

A/C

The compounds of formula I contain at least one chiral centre and may be in the form of enantiomers or enantiomeric mixtures, such as racemates, and if they contain more than one chiral centre, they may also be in the form of diastereoisomers or diastereoisomeric mixtures. The carbon-carbon double bond of the compounds according to the invention is in the transconfiguration in relat:ion to R 2 and Ra, or in relation to A and B, that is to say the compounds of formula I are compounds of the E-series.

ii -2- Compounds of formula I in which R 1 is hydrogen are phosphonous acids, those in which R 1 is alkyl are phosphinic acids, and those in which Ri is hydroxy are phosphonic acids. In the names of the compounds of formula I that are to be regarded as substituted carboxylic acids, the prefixes "phosphino" (RI is hydrogen), "phosphonyl" (RI is alkyl) and "phosphono" (Ri is hydroxy) are used.

Esterified carboxy is, for example, carboxy esterified by an aliphatic or araliphatic alcohol, such as an unsubstituted or substituted lower alkanol or phenyl-lower alkanol, such as corresponding lower alkoxy- or phenyl-lower alkoxy-carbonyl. Esterified carboxy is preferably pharmaceutically acceptable esterified carboxy, such as, for example, esteri- *0*0 S fied carboxy that can be converted into carboxy under physiological conditions. These esters of formula I may also be called prodrug esters.

*0 #0000 Carboxy esterified in a pharmaceutically acceptable manner is, for example, lower alkoxycarbonyl; lower alkoxycarbonyl substituted in a position higher than the a-position by amino, by mono- or di-lower alkylamino or by hydroxy; lower alkoxycarbonyl substituted by carboxy, for example v-carboxy-substituted lower alkoxycarbonyl; lower alkoxycarbonyl substituted by lower alkoxycarbonyl, for example a-lower alkoxycarbonylsubstituted lower alkoxycarbonyl, aryl-lower alkoxycarbonyl, for example unsubstituted or substituted benzyloxycarbonyl, or pyridylmethoxycarbonyl; lower alkanoyloxy-substituted methoxycarbonyl, for example pivaloyloxymethoxycarbonyl; lower alkoxymethoxycarbonyl substituted by o lower alkanoyloxy or by lower alkoxy; bicyclo(2.2.llheptyloxycarbonyl 4 6 0 substituted methoxycarbonyl, such as bornyloxycarbonylmethoxycarbonyl; 3-phthalidoxycarbonyl; 3-phthalidoxycarbonyl substituted by lower alkyl, lower alkoxy or by halogen; or lower alkoxycarbonyloxy-lower alkoxycarbonyl, for example l-(meth.oxy- or ethoxy-carbonyloxy)-ethoxycarbonyl.

Especially preferred prodrug esters are, for example, lower alkyl esters having up to four carbon atoms, such as, for example, butyl or ethyl esters, lower alkanoyloxymethyl esters, such as, for example, pivaloyloxymEthyl ester, lower alkyl esters that have from two to four carbon atoms in each lower alkyl group and are substituted in a position higher ~4~L i -3than the a-position by di-lower alkylamino, such as, for example, 2-diethylaminoethyl ester, and also pyridylmethyl esters, such as 3-pyridylmethyl ester.

In amidated carboxy the amino group is, for example, amino that in unsubstituted, monosubstituted by hydroxy, or mono-or di-substituted by aliphatic radicals, such as amino, hydroxyamino, mono- or di-lower alkylamino or lower alkyleneamino having from 5 to 7 ring members. Preferably, amidated carboxy is pharmaceutically acceptable amidated carboxy, such as, for example, amidated carboxy that can be converted into carboxy under physiological conditions.

o Preferred pharmaceutically acceptable amides are compounds of formula I OO** in which R 5 is carbamoyl, lower alkylcarbamoyl, for example ethylcarbamoyl, di-lower alkylcarbamoyl, for example diethylcarbamoyl, or in the S form of N-(di-lower alkylamino)-lower alkylcarbamoyl, for example N-(2- S diethylaminoethyl)carbamoyl or (3-diethylaminopropyl)carbamoyl.

Q a Within the scope of this invention, alkyl is a saturated aliphatic hydroos. carbon radical having, for example, up to 12 carbon atoms, but especially Shaving up to 8 carbon atoms, the latter range also being represented by the term lower alkyl.

4 a ,wo-Alkylene having from 1 to 3 carbon atoms is methylene, 1,2-ethylene or 1,3-propylene. a,c-Alkylene substituted by alkyl is substitutied at any position. Thus, methylene substituted by alkyl is, for example, 1,1-ethylene, 1,1-butylene or l,l-octylene, 1,2-ethylene substituted by alkyl is, for example, 1,2-propylene, 1,2-butylene, 2,3-butylene, 1,2-pentylene or 1,2-nonylene, and 1,3-propylene substituted by alkyl is, for example, 1,3-butylene, 1,3-pentylene or 1,3-decylene.

Amino substituted by lower alkyl or by aryl-lower alkyl is mono- or dilower alkylamino or aryl-lower alkylamino.

~EpL I -4- Aryl, also in definitions such as aroyl or aryl-lwer alkoxycarbonyl, represents aromatic hydrocarbon radicals that are unsubstituted or substituted by lower alkyl, hydroxy, protected hydroxy, lower alkoxy, halogen, amino, halo-lower alkyl, hydroxy-lower alkvl, amino-lower alkyl or by nitro, and is, for example, unsubstituted or correspondingly substituted 1- or 2-naphthyl, but preferably unsubstituted or correspondi.,ly substituted phenyl, such as phenyl, lower alkylphenyl, for example methylphenyl, hydroxyphenyl, halophenyl, for example 4-halophenyl, such as 4-chlorophenyl, benzyloxyphenyl, lower alkoxyphenyl, for example methoxyphenyl, hydroxymethylphenyl, aminomethylphenyl or nitrophenyl.

The general terms used hereinbefore and hereinafter, unless defined otherwise, have the following meanings: a4 o 4 The term "lower" indicates that groups or compounds so defined contain up to and including 8, preferably up to and including 4, carbon atoms.

O 4 So*o Lower alkyl is, for example, Ci-Cijalkyl, such as methyl, ethyl, n-propyl, isopropyl, n-butyl, isobutyl or tert.-butyl, but can also be Cs-Csalkyl, such as n-pentyl, n-hexyl, n-heptyl or n-octyl, and is preferably methyl.

a S Aryl-lower alkyl, also in definitions such as aryl-lower alkylamino, is, for example, aryl-Ci-Calkyl in which aryl has the meanings given above, and is especially, for example, unsubstituted phenyl-C1-Ciialkyl, such as benzyl or 1- or 2-phenylethyl.

Lower alkenyl contains preferably up to 6 carbon atoms and is bonded by way of an sp'-hybridised carbon atom and is, for example, 2-propenyl, 2or 3-butenyl or 3-pentenyl but can also be vinyl.

Lower alkoxy is especially C 1 -Cqalkoxy, such as methoxy, ethoxy, n-propoxy, isopropoxy, n-butoxy, isobutoxy or tert.-butoxy.

Halogen preferably has an atomic number of up to 35 and is especially chlorine, or also fluorine or bromine, b i, can also be iodine.

I Ri..

Halo-lower alkyl is, for example, halo-Cl-Cialkyl, such as fluoromethyl, trifluoromethyl or 1- or 2-chioroethyl.

Hydroxy-lower alkyl is, for example, mono- or di-hydroxy-Cl-C 7 alkyl, carries the hydroxy group(s) especially in a position higher than thco a-position and is, for example, hyHfroxymethyl or especially mono- or di-hydroxy-C2-G 7 -alkyl, such as 2-hydroxyethyl, 3-hydroxy- or 2,3-dihydroxy-propyl, 4-hydroxy- or 2,4-dihydroxy-butyl, or 5-hydroxy-, hydroxy- or Lower alkoxy-lower alkyl is, for 3xample, mono- or di-C 1 -C~alkoxy-C-,-C 7 alkyl, carries the lower alkoxy group(s), for example, especially in a '~position higher than the a-position and is especially CI-C4--alkoxy- C2-C4-alkyl, for example, 2-methoxy-, 2-ethoxy-, 2-propoxy- or 2-isopropoxy-ethyl, 3-methoxy- or 3-ethoxy-propyl or 3,3-dimethoxy-, 3,3-diethoxy-, 2,3-dimethoxy- or 2,3"diethoxy-propyl or 4,4-dimetboxybutyl, but may also be methoxy-, ethoxy-, dimethoxy-, propoxy- or isopropoxy-methyl.

Mono- or di-lower alkylamimo is, for example, N-Ci-Ct~alkylamino or N,N-di-Ca-Cilalkylamino, such as methylamino, dimethylamino, ethy2lamino, Q diethylamino, propylamino, isopropylanino or butylamino.

t4 Salt, of compounds according to the invention are especially pharmaceutically acceptable non-toxic salts of compovnds of formula I. Such salts are formed, for example, from the carboxy fqroup present in compounds of formula 10 and are especially metal orz ammonium salts, such as alkali metal and alkaline earth metal salts, for exampl(. sodium, potassium, magnesium or calcium salts, and also ammonium salts with ammonia or suitable organic amines, such as lower alkylamines, for example methylamine, diethylamine or triethylamine, hydroxy-lower alkylamines, for example 2-hydroxyethylamine, bis-(2-hydroxyethyl)-amine, tris-(hydroxymethyl)-mfethylamimie or tris-(2-hydroxyethyl)-amine, basic aliphatic esters of carboxylic acids, for example 4-aminobenzoic acid 2-diethylaminoethyl ester, lower alkyleneamines, for example 1-ethylpiperidine, lower alkylenediamines, for example ethylenediamine, cyclo- 6 -6alkylamines, for example dicyclohexylamine, or benzylamines, for example N,N'-dibenzylethylenediamine, benzyltrimethylammonium hydroxide, dibenzylamine or N-benzyl-R-phenylethylamine. Compounds of formula I having a primary or secondary amino group may also form acid addition salts, for example with preferably pharmaceutically acceptable inorganic acids, such as hydrohalic acids, for example hydrochloric acid or hydrobromic acid, sulphuric acid, nitric acid or phosphoric acid, or with suitable organic carboxylic or sulphonic acids, for example acetic acid, propionic acid, succinic acid, glycolic acid, lactic acid, fumaric acid, maleic acid, tartaric acid, oxalic acid, citric acid, pyruvic a'cid, benzoic acid, mandelic acid, malic acid, ascorbic acid, pamoa acid, nicotinic acid, methanesulphonic acid, ethanesulphonic acid, hydroxyethanesulphonic acid, benzenesulphonic acid, 4-toluenesulphonic acid or naphthalenesulphonic acid.

o It is also possible to use pharmaceutically unsuitable salts for isolation or purification. Only the pharmaceutically acceptable non-toxic r salts are used therapeutically, and these are therefore preferred, The compounds prepared in accordance with the invention have valuable S" pharmacological properties. They are, for example, active and selective a °a antagonists of N-methyl-D-aspartic acid (NMDA)-sensitive excitatory amino S, acid receptors in mammals. They atr therefore suitable for the treatment O of diseases that respond to a blocking of NMDA-sensitive receptors, such as, for example, cerebral ischaemia, muscular spasms (spasticity), convulsions (epilepsy), conditions of anxiety or manic condition6.

These advantageous effects may be demonstrated in in vitro or in in vive test arrangements. For these, preferably mammals are used, for example mice, rats or monkeys, or tissue or enzyme preparations from such mammals. The compounds may be administered enterally or parentally, preferably orally; or subcutaneously, intravenously or intraperitoneally, for example in gelatin capsules or in the form of aqueous suspensions or solutions. The dosage to be used in vivo may range from 0.1 to 600 mg/kg, -7gg nd A. M tu 7 A 8 6 1 preferabLy from 1 to 300 mg/kg. In vitro, the compounds may be used in 44 the form of aqueous solutions, the concentrations ranging from 10 to -8 molar solutions.

The inhibiting action on the NMDA-sensitive excitatory amino acid receptors may be determined in vitro by measuring, in accordance with G.

Fagg and A. Matus, Proc. Nat. Acad. Sci., USA, 81, 6876-80 (1984), to what extent the bonding of L-JH-glutamic acid to NMDA-sensitive receptors is inhibited. In vivo, the inhibiting action on NMDA-sensitive excitatory amino acid receptors may be demonstrated by the inhibition of NMDAinduced convulsions in mice.

3 The anti-convulsive properties of the compounds according to the invention may furthermore be shown by their effectiveness in preventing audiogenically induced attacks in DBA/2 mice (Chapman et al., Arzneimittel-Forsch. 34, 1261, 1984).

S The anti-convulsive properties may furthermore be shown by the effectiveness of the compounds according to the invention as electric shock antagonists in mice or in rats.

S An indication of the anxiolyt,c activity of the compounds of the present invention is given by their pronounced effectiveness in the conflict S model according to Cook/- Davidson (Psychopharmacologia 15, 159-168 (1968)).

S The pronounced effectiveness of the compounds of formula I depends to a surprisingly high extent on the configuration at the double bond. For example, L'Te racemate of D-2-amino-5-phosphono-3-cis-pentenoic acid known from Agric. kiol. Chem. 41, 573-579 (1979), B. K. Park et al., proves, for example in its ability to bond to the NMDA-sensitive receptor, to be far inferior to the racemate of the 2-amino-5-phosphono-3-trans-pentenoic acid according to the invention (in the Examples these compounds are referred to as compounds of the "E-series"). Compounds of the formula I, wherein the carbon atom carrying the group R6 has R-configuration, have been found to be especially active.

8 The manufacture of compounds of formula I in which R2 is hydrogen, alkyl or aryl is preferred.

The invention relates especially to a process for the manufacture of compounds of formula I in which RI is hydrogen, alkyl having up to and including 12 carbon atoms, or hydroxy, R 2 is hydrogen, lower alkyl, halolower alkyl, hydroxy-lower alkyl, lower alkoxy-lower alkyl, phenyl-lower alkyl that is unsubstituted or substituted in the phenyl moiety, lower alkenyl, halogen, or unsubstituted or substituted phenyl, R 3 is hydrogen, lower alkyl or unsubstituted or substituted phenyl, R4 is hydrogen or lower alkyl, R 5 is free or pharmaceutically acceptable esterified or amidated carooxy, R6 is amino, or moiio- or di-lower alkylamino, A is unsubstituted or lower alkyl-substituted a,W-alkylene having from 1 to 3 carbon atoms or is a bond, and B is methylene or a bond, with the S proviso that A is other than a bond when B is a bond, the substituents of phenyl being selected from the group consisting of lower alkyl, hydroxy, lower alkoxy, halogen, amino, halo-lower alkyl, hydroxy-lower alkyl, amino-lower alkyl end nitro, and wherein "lower" groups possess up to and including 8 carbon atoms, and also to pharmaceutically acceptable salts thereof.

Preferred is the use of the process for the manufacture of compounds of formula I in which RI to R 4 A and B are as defined hereinbefore and, on S the one hand, R 5 is lower alkoxycarbonyl, or lower alkoxycarbonyl sub- S stituted by amino, mono- or di'lower alkylamino, hydroxy or by lower alkanoyloxy and R6 is amino or lower alkylamino or, on the other hand, Rs is carboxy and R6 is amino, especially the R-enantiomers thereof in respect of the atom carrying the amino group, and pharmaceutically 1 acceptable salts thereof.

Also preferred is the use of the process for the manufacture of compounds of formula I in Which Ri, R4 to R6 and A and B are as defined directly hereinbefore and in which R2 and Ra3 independently of one another, each represents hydrogen, lower alkyl, phenyl or phenyl substituted by lower alkyl, hydroxy, lower alkoxy, halogen, amino, halo-lower alkyl, hydroxy-

I

9 lower alkyl, amino-lower alkyl or by nitro, especially the R-enantiomers thereof in respect of the atom carrying the amino group, and pharmaceutically acceptable salts thereof.

The invention relates especially to a process for the manufacture of compounds of formula I in which RI is hydrogen, alkyl having up to and including 12 carbon atoms, or hydroxy, R 2 is hydrogen, lower alkyl, phenyl, halophenyl or phenyl-lower alkyl, R 3 and Ri are hydrogen or lower alkyl and, on the one hand, R 5 is alkoxycarbonyl or hydroxy-lower alkoxycarbonyl and R6 is amino or mono-lower alkylamino or, on the other hand, Rs is carboxy and R6 is amino, A in each case being unsubstituted or o" lower alkyl-substituted ,to-alkylene having from 1 to 3 carbon atoms or f being a bond and B in each case being methylene or a bond, with the 4 64 proviso that A is other than a bond when B is a bond, especially the a S R-enantiomers thereof in respect of the atom carrying the amino group, and pharmaceutically acceptable salts thereof.

4a 4 The invention relates especially to a process for the manufacture of compounds of formula I in which RI is hydrogen, alkyl having up to and t o including 12 carbon atoms, or hydroxy, Ra is hydrogen, lower alkyl or halophenyl, R3 is hydrogen or halophonyl, Ri, is hydrogen and, on the one hand, Rs is lower alkoxycarbonyl or hydroxy-lower alkoxycarbonyl and R6 is amino or mooelower alkylamino or, on the other hand, R 5 is carboxy and Rs is amino, A in each case being e,w-alkylene having from 1 to 3 carbon atoms or being a bond and B in each case being methylene or a S bond, with the proviso that A is other than a bond when B is a bond, especially the R-enantiomers thereof in respect of the atom carrying the amino group, and pharmaceutically acceptable salts thereof.

e 'The invention relates especially to a process for the manufacture of compounds of formula I in which Ri is hydrogen, lower alkyl or hydroxy, Rz is hydrogen or lower alkyl, R3 and Ri are hydrogen and Rs is on the one hand lower alkoxycarbonyl or on the other hand carboxy, and R6 is amino, A in each case being ai,-alkylene having from 1 to 3 carbon atoms 1-Lr I 10 and B in each case being a bond, especially the R-enantiomers thereof in respect of the atom carrying the amino group, and pharmaceWuically acceptable salts thereof.

The invention relates most especially to a process for the manufacture of compounds of formula I in which RI is hydroxy, R 2 is hydrogen or lower alkyl, R 3 and R4 are hydrogen and Rs is lower alkoxycarbonyl or carboxy, Re is amino, A is methylene and B is a bond, especially the R-enantiomers thereof in respect of the atom carrying the amino group, and pharmaceutically acceptable salts thereof.

The invention relates to the manufacture of the compounds mentioned specifically in the Examples and to the pharmaceutically acceptable salts thereof.

I t The process of the invention is characterised in that in a compound of formula S--Z (II), 2 12 in which Z 1 is free or protected hydroxy, Z2 is an RI group or protected hydroxy, Zs is an Rs group or protected carboxy, Z6 is a protected R6 group, and RI, R2, R3, Rs, R6, A and B are as defined hereinbefore, the protected groups Z6 and, where applicable, ZI, Z2 and/or Z$ are fre by treatment with a tri-lower alkylhalosilane and, if desired, the resulting compound is converted into a different compound of formula I, a resulting mixture of optical isomers is resolved into the components and the desired isomer is separated off, and/or a resulting free compound is converted into a salt or a resulting salt is converted into the free compound or into a different salt, Protected hydroxy Z 1 and/or ZZ in intermediates of formula II Is, for example hydroxy etherified by an aliphatic alcohol, such as hydroxy etherified by a lower alkanol, lower alkenol or lower alkynol each of which is unsubstituted or substituted by halogen or, in a position higher t ,han the at-position, by hydroxy, oxo, lower alkoxy, lower alkanoyloxy and/or by mono- or di-lower alkylamino, and is, for example, lower alkoxy, halo-lower alkoxy, or corresponding hydroxy-, oxo-, lower alkoxy-, lower alkanoyloxy- or mono- or di-lower alkylamino-lower alicoxy.

Compounds of formulA II in which Z, and/or Z 2 are etherified hydroxy are esters of the phosphorus-containing acid group and, depending on the meaning of R1, are phosphonous acid esters, phosphinic acid esters or phosphonic acid ers. Preferred esters are the respective lower alkyl esters and hydroxy-lower alkyl esters.

4:;::Groups Z6 in intermediates of formula II are, for example, R 6 grnups *substituted by acyl, that is to say acylamipo that is unsubstitut(.d or Nabtituted by lower alkyl or by aryl-lower alkyl in which acyl is the acyl radical of an organic acid having, for example, up to 13 carbon t atomis, especially ani alkanecarboxylic acid that in unsubstituted or substituted, for example, by halogen, amino or by phenyl, or benzoic acid that is unsubstituted or substituted, for example Ily halogen, lower alkoxy or by nitro, or of a carbonic acid seniiester, Such aoyl groups are, for examiples lower alkanoyl, such formyl, acetyl or propionyl, halo-lower allcanoyl, such as 2-haloacetyl, especially 2-fluoro-, t 4 2-bromo-, Z-iodo-t 2,2,2-trifluoro- or 2,2,2-trichloz'o-acetyl, aroyl, IAt such as unsubstituted or substituted benzoyl, for example benzoyl, halobenzoyl, such as 4-chlorobenzoyl, lower alkoxybenzoyl, such as 4-methoxybenzoyl, or nitrobenzoyl) such as 4-nitrobenzoyl. The following are also especially sutitable: lo ,r alkenyloxycarbonyl, for example allyloxycarbonyl, ot especially lower alkoxycarbonyl that is unsubstizwted or substituted In the 1- or 2-'position, such as, especially, lower alkoxycarbonyl, for example tertiary butoxycarbony. and also 4/f methoxy- or ethogy-carbonyl, and also unsobstituted or substituted benzylox~ycarbonyl, for example benzyloxycarbonyl or 4-nitrobenzyloxycarhp-. or aroylmothoxycarbonyl in which the aroyl group is benzoyl that is unsubstituted or substituted, for example, by halogen, such As bromine, for example phenacyloxyciarbonyl or bromophenacyloxycarbonyl.

-12tiermore, in a corresponding acylamino group Z6, acyl may be alkanoylamino substituted by amino and/or by phenyl, carbamoyl, carboxy, imidazolyl, lower alkyithia, tetrahydropyrrolyl, hydroxy, indolyl or by hydroxyphenyl, and thus inclues, for example, the acyl radicals of amino acids, for example naturally occurring amino acids, such as alanyl, asparaginyl, aspartyl, glycyl, histidyl, isoleucyl, leucyl, lysyl.

methionyl, phenylalanyl, prolyl, seryl, threonyl, tryptophyl, tyrosyl or valyl; also included are the acyl radicals of oligopeptides, for example di- or tri-peptides, such as oligopeptides of alanine, asparagine or aspartic acid.

q~~':Furthermore, protected amino Z 6 may be a diacylamino group. In this group 0~ diacyl is, for exaf~iple, two acyl radicals of the definitions given 0 hereinbefore, or diacyl is, for example, the acyl radical of an, organic o dicarboxylic acid having, for e,,,atnple, up to 12 carbon atoms, especially a corresponding aromatic dicarboxylic acid, such as phthalic acid. Such a o~ o,~group is especially phthalimido.

In addition, protected amino Z6 may also be amino substituted by sub- *00.0 stituted los'er alkoxycarbonyl, such as amino substituted by 2-halo-lower 0 alkoxycarbonyl, for example 2,2,2-trichloroethoxycarbonyl, 2-chloroethoxycarbonyl, 2-bromoethoxycarbonyl or~ 2-iodoethoxycarb6.syl, or by 04 2-(tria-substituted silyl)-ethoxycarbonyl, such as 2-tni-lower alkylsilylethoxycarbonyl, for example 2-trimethylailylethoxycarbonyl or 2-(di-n-butyl-methyl-silyl) -ethoxycarbonyl, or by 2-triarylsilyethoxycarbonyl, such as -2-triphenylsilylethoxycarbonyl, or etherified mercaptoamino or silylamino, or may be in the form of an enamino, nitro or azido group. An etherified mercaptoamino group is especially a phenylthioamino group that is unsubstituted or substituted by lower alkyl, such as methyl 7 or tert.-butylt lower alkoxy, such as methoxy, halogen, such as chlorine or bromine, and/or by nitro, or a pyridylthioamino groupo Correspondirhg groups are, for oxample, 2- or 4-nitrophonylthioamino or 2-pyridylthioamino. A silylamino group is especially an organic silylamino group. in such groups the silicon atom contains an substituent(s) preferably lower alkyl, for example methyl, ethyl, n-butyl. or tert.-butyl, also aryl, for example phenyl. Suitable silyl groups are especially tri-lover alkyl- 13 silyl, especially trimethylsilyl or dimethyl-tert.-butylsilyl. Enamino groups contain at the double bond in the 2-position an electronattracting substituent, for example a carbonyl group. Protecting groups of this kind are, for example, 1-acyl-lower alk-1-en-2-yl radicals in which acyl is, for example, the corresponding radical of a lower alkanecarboxylic acid, for expmple acetic acid, of a benzoic acid that is Unsubstituted or substituted, for example, by lower alkyl, such as methyl or tert.-butyl, lower alkoxy, such as metho-:y, halogen, such as chlorine, and/or by nitro, or especially of a carbonic acid semiester, such as a carbonic acid lower alkyl semiester, for example methyl semiester or ethyl semiester, and lower alk-1-ene is especially l-propene.

Corresponding protecting groups are especially 1-lower alkanoyl-prop-1en-2-yl, for example l-acetyl-prop-1l-en-2-yl, or 1-lower alkoxycarbonylprop-i-en-2-yl, for example 1-ethoxycarbonyl-prop-l-en-2-yl.

Protected carboxy Z5 is customarily protected in esterified form, it being possible for the ester group to be cleaved under reductive, such an hydrogenolytic, or solvnlytic, 9such as acidolytic or hydrolytic, such as acid-hydrolytic, basic-hydrolytic or neutral-hydroytic, conditions. A protected carboxy group may furthermore be an esterified carboxy group S that can be cleaved under physiological conditions or that can readily be converted into a different functionally modified carboxy group, such as into a different esterified carhoxy group. Such esterified carboxy groups contain as esterifying groups especially silyl groups, especially trilower alkylsilyl groups, or lower alkyl groups that are suitably sub- I to stituted in the 1- or 2-position. Preferred carboxy groups in esterified form are, inter alia, tri-lower alkylsilyloxycarbonyl, for example trimethylsilyloxycarbonyl, (hetero-)arylmethoxycarbonyl having from 1 to 3 aryl radicals or having one monocyclic heteroaryl radical, these being unsubstitutad or mono- or poly-substituted, for example, by lower alkyl, such as tert.-lower alkylj for example tert.-butyl, halogen, for example chlorine, and/or by nitro. Examples of svch groups are benzyloxycarbonyl that is unsubstituted or substituted, for example in the manner mentioned above, for example 4-nitrobenzyloxycarbonyl, diphenylmethoxyearbonyl or triphenylmethoxycarbonyl that is unaubstituted or substituted, for example in the manner mentioned above, for example diphenylmethoxycar- 14 bonyl, or picolyloxycarbonyl, for example 4-picolyloxycarbonyl, or furfuryloxycarbonyl, such as 2 -furfuryloxycarbonyl that is unsubstituted or substituted, for example in the manner mentioned above.

Protected hydroxy Zi and/or Za is especially lower alkoxy, such as methoxy, ethoxy or isopropoxy, protected carboxy is especially tri-lower alkylsilyloxycarbonyl, such as trimethylsilyloxycarbonyl, and protectea amino Z 6 unsubstituted or substituted by lower alkyl or by aryl-lower alkyl is especially lower alkanoylamino, especially formylamino, N-lower alkanoyl-N-lower alkylamino, especially N-formyl-N-lowor alkylamino, for example N-formyl-N-methylamino, or lower alkoxycarbonylamino, preferably tertiary butoxycarbonylamino.

o *9 Tri-lower alkylhalosilanes are, for example, tri-lower alkyliodosilanes Sor, especially, tri-lower alkylbromosilanes, preferably those in which *o o the lower alkyl groups are identical Ci-C4alkyl radicals. Trimethylbromosilane is preferred, with trimethyliodosilane as second choice.

Freeing the protected groups, that is to say freeing hydroxy from 9.

protected hydroxy groups ZI and/or Z 2 freeing carboxy from protected 944 carboxy groups Zs and/or freeing amino that is unsubstituted or substituted by lower alkyl or by phenyl-lower alkyl fzom protected amino groups Z 6 by treatment with a tri-lower alkylhalosilane is effected, for example, in an inert solvent, such as a halogenated, preferably aliphatic hydrocarbon, for example dichloromethane or, less preferably, tri- or 4 tetra-chloromethane, trichloroethan or tetrachloroethane, in a temperature range of approximately from to +50 0 C, preferably from approximately 0°C to approximrtely 30°C, fov example at temperatures in the region of room temperature, that is tt, say at from approximately 1500 to a approximately 25*C, advantageously under substantially anhydrous conditions and under an inert gas, for example under argon or nitrogen.

Working up is carried out in a manner known per se, two purifying methods especially having proved advantageous. Either the crude product can be converted into a readily volatile derivative, for example by silylation, and recovered as such by distillation and then desilylated, or the cude 15 product can be treated with an agent that reacts with excess acid, such as hydrohalic acid, thereby removing it. Suitable agents are, for example, compounds to which a corresponding acid can be added, for example lower alkylene oxides (epoxides), such as propylene oxide.

If compounds of formula I in which Rs is esterified or amidated carboxy, such as lower alkoxycarbonyl or carhamoyl, are desired as end products, the starting materials of formula II and the process conditions can be so selected that although in the last step Zi, Z2 and Z 6 are freed, Zs, which represents the desired R5 group, remains unaffected.

An especially preferred process variant is accordingly directed to the Smanufacture of compounds of formula I in which R 5 is C 1 -C4alkoxycarbonyl Sand R 6 is amino. In this process variant the starting materials used are 44 a* a' preferably compounds of formula II in which Z1 and Za are lower alkoxy or lower alkoxy substituted in a position higher than the a-position by halogen, such as chlorine, Z 5 is C1-Ciialkoxycarbonyl and Z 6 is lower alkanoylamino, such as formylamino, or lower alkoxycarbonylamino, such as tert.-butoxycarbonylamino. Starting from such compounds of formula II the freeing of the protected groups can be so controlled by treatment in an inert solvent, such as a halogenated hydrocarbon, for example dichloromethane, at temperatures in the region of room temperature, with a reagent such as trimethylbromosilane, and by subsequent treatment with a lower alkanol, such as ethanol, and a substance absorbing hydrogen halide, such as an aliphatic epoxide, especially an epoxy-lower alkane, for example propylene oxide, that compounds of formula I in which R 1 is hydroxy, R 5 is Ci-C 4 alkoxycarbonyl, R6 is amino and the variables R 2

R

3 and Rj, Are as defined for formula I, are obtained directly.

This process is especially preferred for the manufacture of compounds of formula I in which A is methylene or 1,3-propylene and B is a bond, R 3 and R4 are hydrogen and R2 is alkyl having up to 4 carbon atoms, such as methyl.

i 16 Another especially preferred process variant is the manufacture of compounds of formula I in which Rs is carboxy. In this case the starting materials used are preferably compounds of formula II in which Zi and Z 2 are lower alkoxy or lower alkoxy substituted in a position higher than the a-position by halogen, such as chlorine, Z 5 is optionally protected carboxy and Zg is lower alkoxycarbonylamino, especially a-branched lower alkoxycarbonylamino, such as tert.-butoxycarbonylmino. In this case, the carboxy group is preferably, but not necessarily, intermediately protected, for example by treatment with a silylation agent, such as an N,O-silyl-lower alkanoic acid amide, for example with N,O-trimethylsilylacetamide.

Intermediates of formula II are preferably manufactured by reacting a compound of formula to#

(II),

t 9 X-Ain which R, R R4, A and B are as defined for formula I, Z5 has the r meaning of R 5 or is protected carboxy, Z 6 is a protected R 6 group and X is reactive esterified hydroxy, with a compound of formula t t ZiR

(IV),

2 S in which Zi is fret or protected hydroxy, Zz has the meaning of Ri or is protected hydroxy and R is an etherifying group, and can be used without being isolated or specially purified.

Compounds of formula III can be manufactured, for example, by reacting an N-protected aminomalonic acid ester of formula V Z-zS K6 17 in which Zs and Z5 are identical or different esterified carboxy groups, for example lower alkoxycarbonyl groups, in a manner known per se with a compound of formula 3

(VI)

X-A-

12 in which X and independently of one another, each represents reactive esterified hydroxy, such as halogen. The resulting compounds of formula

(VII)

X-A- Zs 6 a can be converted into compounds of formula III in which RI is hydrogen by S' hydrolysis, for example under hydrolytic conditions, such as the conditions of an aridic hydrolysis, for example with hydrohalic acids, such as hydrochloric acid, preferably with heating, and by decarboxylation, or by dealkoxycarbonylation, without previous hydrolysis, by heating in an aqueous aprotic solvent, such as dimethyl sulphoxide, in the presence of an alkali metal halide, such as sodium chloride.

4 This variant is accordingly especially sr' able for producing compounds III in which Ri, is hydrogen, ZS is free or esterified carboxy and

Z

6 is protected amino, such as lower alkanoylamino.

Intermediates III in which A is methylene that is unsubstituted or substituted by alkyl, B is a bond, X is halogen and Z6 is formylamino can furthermore be produced by reacting a compound of formula Sf D=C

(VIII),

wherein D denotes optionally alkylated methylidene, such as a corresponding a,8-unsaturated aldehyde, for example acrolein or methacrolein, with an a-isocyanoacetic acid derivative, such as an a-isocyanoacetic acid lower alkyl ester. With suitable catalysis, such as with low valency 1 18 metal salts, that is to say metal salts derived from metals of groups I and II of the Periodic Table of Elements, for example corresponding metal oxides or metal halides, such as zinc chloride, cadmium chloride, silver oxide or, preferably, copper oxide or complexes of gold-I-tetrafluoroborate with aliphatic or 'ycloaliphatic isocyanides, for example bis- (cyclohexylisocyanide)gGld-I-tetrafluoroborate, there are thus obtained in a manner known per se 5-vinyl-2-oxazoline-4-carboxylic acid derivatives, for example esters of formula D=k 3 /Zs 0--0 o4 .o which can be converted into the open-chained compounds of formula 0 &0 0 0

D==

S3 6 in which D is unsubstituted or alkyl-substituted methylidene. These com- 4 'o pounds can in turn be converted by selective halogenation, such as bromination or chlorination, preferably with cooling and with displace- S ment of the double bond in the manner of an allyl rearrangement, into S compounds of formula III.

Another process for the manufacture of compounds II in which R4 is hydrogen, A is methylene or 1,3-propylene and Rs is carboxy, is based on 0 the principle that a compound of formula 0 VxI RAh 19 in which RA and RB are hydrogen or preferably lower alkyl, such as methyl, and R C Is an amino-protecting group, is condensed with a 2-R 2 acetic acid ester or condensed first with a 1-R 2 -ethene-metal compound, for example with isopropenylmagnesium bromide, and subsequently with an acetic acid ester, in the resulting compound of formula /3 iZ f3 I Z 0 N (XIIa) or o (XIIb) R \R C \R C A A B in which Z5 is esterified carboxy, for example lower alkoxycarbonyl, this group is reduced to hydroxymethyl, for example by means of diiso- S butylaluminium hydride, the hydroxymethyl group is halogenated, for example brominated by means of tetrabromomethane/triplenylphosphine, the resulting compound of formula 4 4 3 /0- S'-RA XIII),

/-RA

C

4 in which A denotes methylene or 1,3-propylene and X is halogen, for example bromine, is further reacted with a compound of formula IV, the oxazolidine ring is cleaved, for example, by means of an ion exchanger, such as Amberlyst 15I', and, in the resulting compound of formula 3 S-A H20H (XIV) 2 2 in which Z6 is a protected amino group of formula RC-NH-(II'), the hydroxymethyl group is oxidised to carboxy in customary manner.

When carrying out the above-described processen for the manufacture of intermediates III and the further reaction of the same to form intermediates II it is not necessary to isolate all of the intermediate r ~i

I

CP- i 20 stages. For example, especially the conversion of compounds X into compounds III and the further'reaction thereof with compounds IV to form intermediates II can advantageously be carried out in situ.

A preferred variant of the process of the invention accordingly consists of the following: a compound of formula Z5

(III),

r 12 in which R 2

R

3 Ri, A and B are as defined for formula I, Zs has the meaning of Rs or is protected carboxy, Z 6 is a protected R6 group, for example protected amino, and X is reactive esterified hydroxy, is reacted with a compound of formula I i Zi-- (IV), 2 S in which Zi is free or protected hydroxy, Z2 has the meaning of RI or is protected hydroxy and R is an etherifying group, the protected groups Z 6 and, where applicable, Zi, Za and/or Z 5 are freed by treatment with a S tri-lower alkylhalosilane, for example with trimethylbromosilane, and, if desired, a resulting compound of formula I is converted into a different compound of formula I and/or, if desired, a resulting compound of formula I is converted into a salt or a resulting salt is converted into a different salt or into a free compound of formula I and/or, if desired, an optical isomer is isolated from a mixture of stereoisomeric forms of a resulting compound of formula I or of a salt thereof.

A A reactive esterified hydroxy group, such an X, is a hydroxy group esterified by a strong organic acid, for example a hyaroxy group esterified by an aliphatic or aromatic sulphonic acid (such as a lower alkaneaulphonic acid, especially mathanesulphonic acid, trifluoromethanesulphonic acid, especially benzenesulphonic acid, p-toluenesulphonic acid, p-bromobenzenesulphonic acid and p-nitrobenzenesulphonic acid) or ii: rl C~ _iX 21 by a strong inorganic acid, such as, especially, sulphuric acid, or a hydrohalic acid, such as hydrochloric acid or, most preferably, hydriodic acid or hydrobromic acid.

Attention is drawn in this connection to the surprising finding that the manufacture of the intermediates II and their further reaction according to the invention to form the end products I can be carried out stereoselectively. That is, neither in the reaction sequence III IV -4 II or IIa I, nor in the reaction sequences X III and XI XII XIII 4 XIV 4 II is there reversal of configuration or significant racemisation.

The process of the invention is therefore excellently suitable for the direct manufacture of compounds of formula I with the preferred R-configuration at the carbon atom carrying the avino group R 6 The invention to also relates to the manufacture of sterically homogeneous compounds of Sformula I and sterically homogeneous intermediates of formulae II, III, X, X, II, XIII and/or XIV.

According to another preferred process variant, a compound of formula .H R *a Zs (X)

D==

1-, is subjected to selective halogenation, for example by means of thionyl chloride, to form the corresponding intermediate III, and this is reacted in situ, that is to say without being isolated, with component IV, As mentioned, compounds obtainable in accordance with the invention can be converted into different compounds of formula I. In particular, a free amino group R6 may be substituted, for example converted into an unsubstituted or phenylated alkylamino group, free carboxy Rs may Le esterifled, or esterified or amidated carboxy Rs may be converted into free carboxy, and/ov free or esterified carboxy R 5 may be converted into amidated carboxy.

c~ 22 To convert an amino group into an unsubstituted or phenylated alkylamino group the amino group may be alkylated by substitution, for example with a reactive esterified optionally phenylated alkanol, such as an alkyl halide, or by reduction, such as with an aldehyde or ketone, and also with catalytically activated hydrogen or, in the case of formaldehyde, advantageously with formic acid as reducing agent.

Free carboxylic acids of formula I or salts thereof may be converted according to known processes by suitable alcohols or corresponding derivatives thereof into the corresponding esters, that is to say into compounds of formula I that are, for example, in the form of lower alkyl esters, aryl-lower alkyl esters, lower alkanoyloxymethyl esters or lower alkoxycarbonyl-lower alkyl esters.

*4.

4* For the esterification, a carboxylic acid may be reacted directly with a diazoalkane, especially diazomethane, or with a corresponding alcohol in i the presence cf a strongly acidic catalyst (for example a hydrohalic acid, sulpl'tric acid or an organic sulphonic acid) and/or of a dehydreting agent (for example dicyclohexylcarbodiimide), Alternatively, a 0« the carboxylic acid may be converted into a reactive derivative, such as into a reactive ester, or into a mixed anhydride, for exanle with an acid halide (for example, especially an acid chloride), aind this S activated intermediate is reacted with the desired alcohol, Compounds of formula I in which Rs is esterified carboxy, such as, S especially, lower alkoxycarbonyl, for example ethoxycarbonyl, can be converted into compounds of formula I in which Rs is carboxy, for example by hydrolysis especially in the presence of inorganic acids, such as hydrohalic acids or sulphuric acid or, less preferably, aqueous alkalis, such as alkali metal hydroxides, for example lithium or sodium hydroxide.

In this connection attention is drawn to the fact that also carboxy can be freed from esterified carboxy in such a manner that no significant racemisation occurs. This can be achieved especially by treatment with from approximately 0.2N to approximately 4N, for example approximately IN, that is to say from approximately 0.5N to approximately 2N, aqueous mineral acid, if necessary while heating, for example at from approxir 1, i; i 23 mately 60"C to approximately boiling temperature, that is to say approximately 100°C. Surprisingly, the hydrolysis, for example, of phosphonic acid carboxylic acid lower alkyl esters of formula I, proceeds with a high yield even without the addition of acidic or basic reagents. A preferred process for the manufacture of carboxylic acids of formula I from the corresponding lower alkyl esters, such as the respective ethyl esters, therefore consists in acidic hydrolysis by treatment with from approximately 0.2N to approximately 4N aqueous mineral acid, for example hydrochloric acid, sulphuric acid, phosphoric acid or the like, and also in the possibly autocatalytic hydrolysis in water, preferably at elevated temperatures, such as with heating under reflux.

S The above reactions are carried out according to standard methods in the absence or presence of diluents, preferably those that are inert towards the reagents and are solvents therefor, in the presence of catalysts, °6 condensation agents or the other agents and/or in an inert atmosphere, at low temperature, room temperature or elevated temperature, preferably at the boiling point of the solvents used, at atmospheric or superatmospheric pressure, S' The invention includes furthermore any variant of the present processes in which an intermediate obtainable at any stage of that process is used as starting material and the remaining steps are carried out, or the process is discontinued at any stage, or in which the starting materials are formed under the reaction conditions or in which the reactants are used in the form of their salts or optically pure antipodes. There should especially be used in these reactions those starting materials that result in the formation of the compounds ment.oned hereinbefore as being S4 especially valuable, The invention relates also to novel starting materials and processes for their manufacture.

Depending on the choice of starting materials and methods, the novel compounds may be in the form of one of the possible optical isomers or in the form of mixtures thereof, for example depending on the number of 24 asymmetric carbon atoms they may be in the form of pure optical isomers, such as antipodes, or mixtures of optical isomers, such as racemates, or mixtures of diastereoisomers from which one antipode, if desired, may be isolated.

Resulting mixtures of diastereoisomers and mixtures of racemates may be separated in known manner on the basis of the physico-chemical differences between the constituents into the pure isomers, diastereoisomers or racemates, for example by chromatography and/or fractional crystallisation.

The resulting racemates (racemic diastereoisomers) may furthermore be 0e separated into the optical antipodes according to methods known per se, for example by recrystallisation from an optically active solvent, with the aid of microorganisms or enzyme-catalyst in free or in an immobilised form or by reaction of an acidic end product with an optically active S* base that forms salts with the vacemic acid, and separation of the salts obtained in this manner, for example on the basis of their different solubilities, into the diastereoisomers, from which the antipodes can be freed by the action of suitable agents. Basic racemic products can also be separated into the antipodes, for example by separation of the diastereoisomeric salts thereof, for example by fractional crystallisation of the d- or l-tartrates thereof. Any racemic intermediate or starting material can be separated in a similar manner, Finally, the compounds according to the invention are obtained either in free form or in the form of their salts, Any resulting base can be converted into a corresponding acid addition salt, preferably using a pharmaceutically acceptable acid or an anion-exchange preparation, or t C resulting salts can be converted irto the corresponding free bases, for example using a stronger base, such an a metal or ammonium hydroxide or a basic salt, for example an alkali metal hydroxide or carbonate, or a cation-exchange preparation. A compound of formula I can also be converted into the corresponding metal or ammonium salts, These or other salts, for example the picrates, can also be used for the purification of resulting bases. The bases are converted into salts, the salts are 25 separated and the bases are freed from the salts. In view of the close relationship between the free compounds and the compounds in the form of their salts, whenever a compound is mentioned in this Application, a corresponding salt of that compound is also included, provided that this is possible or appropriate under the given circumstances.

The compounds, including their salts, can also be obtained in the form of their hydrates or contain other solvents used for the crystallisation.

The pharmaceutical preparations according to the invention are those that are suitable for enteral, such as oral or rectal, and parenteral administration to mammals, including man, for the treatment or prevention •t of diseases that respond to the blocking of NMDA-receptors, such as, for example, cerebral ischaemia, muscular spasms (spasticity), convulsions S(epilepsy), conditions of anxiety or manic conditions. They comprise an effective amount of a pharmacologically active compound of formula I or a S'r pharmaceutically acceptable salt thereof, on its own or in combination with ono or more pharmaceutically acceptable carriers.

The pharmacologically active compounds of the invention can be used in the manufacture of pharmaceutical compositions that comprise an effective amount of the active compound on its own or in conjunction or admixture with excipients or carriers that are suitable for enteral or parenteral administration. Preferred are tablets and gelatin capsules that comprise the active constituent together with a) diluents, for example lactose, dextrose, sucrss, mannitol, sorbitol, cellulose and/or glycine, b) glidants, for example silicon dioxide, talc, stearic acid, the magnesium or calcium salt thereof and/or polyethylene glycol, for tablets also c) binders, for example magnesium aluminium silicate, starch paste, gelatin, tragacanth, methylcellulose, sodium carboxymethylcellulose and/or polyvinylpyrrolidone, if desired d) dispersing agents or disintegrators, for example starches, agar, alginic acid or the sodium salt thereof, or foaming mixtures and/or e) absorbents, col(uring agents, flavourings and sweeteners, Injectable preparations are preterably aqueoua isotonic solutions or suspensions, and suppositories are advantageously produced from fatty emulsions or sutpensions. These compositions may be sterilised 26 and/or contain adjuvants, such as preservatives, stabilisers, wetting agents or emulsifiers, solubilisers, salts for regulating the osmotic pressure and/or buffers. In addition they may also contain other therapeutically valuable substances. These preparations are manufactured according to conventional mixing, granulating or coating methods and contain approximately from 0.1 to 100 preferably approximately from 1 to 50 active constituent. A unit dose for a mammal weighing approximately from 50 to 70 kg may contain approximately from 1 to 500 mg, preferably approximately from 10 to 500 mg, of active constituent.

The following Examples are intended to illustrate the invention and do not represent limitations. The temperatures are in degrees Celsius and S all parts are quoted in the form of parts by weight. Unless stated otherwise, all evaporation is carried out under reduced pressure, Spreferably approximately from 2 to 13 Kilopascal (kPa), Example 1: E-2-amino-4-methyl-5-phosphono-3-pentenoic acid ethyl ester a) 5-(2-propenyl)-oxazoline-4-carboxylic acid ethyl ester (1) 1.6 g of red copper(I) oxide are introduced into 200 ml of benzene. A ,4 solution of 140 g of isocyanoacetic acid ethyl ester and 105 g of freshly distilled methacrolein in 200 ml of benzene is added dropwise to this suspension within a period of 10 minutes with vigorous stirring, during which time the reaction temperature is kept at between 30 and 32' by cooling with ice. When the addition is complete, the mixture is kept at S 30-320 until the exothermic reaction subsides, and is then stirred at room temperature for one hour. After excess copper(I) oxide has been filtered off, the filtrate is concentrated by evaporation in vacuo at 600 ml of ether are added to the residue, which is then filtered 8 K over Celite and concentrated to dryness by evaporation in vacuo. In this manner, 5-(2-propenyl)-2-oxazolire-4-carboxylic acid ethyl ester is obtained in the form of a colourluss oil having a boiling point of 110-1300 (5.3 Pa).

27 b) E-2-formylamino-3-hydroxy-4-methyl-4-pentenoic acid ethyl ester (2) 139 g of 5-(2-propenyl)-2-oxazoline-4-carboxylic acid ethyl ester are dissolved in 70 ml of tetrahydrofuran, and 27.4 g of water and 3.5 g of triethylamine are added thereto. The reaction mixture is stirred at 65-70' for 62 hours and, after cooling, is taken up in 200 ml of dichloromethane. The solution is dried over 200 g of magnesium sulphate, filtered and concentrated by evaporation in vacuo. Purification of the viscous oil which remains by column chromatography (silica gel; hexane/ ethyl acetate 3:2) yields 2-formylamino-3-hydroxy-4-methyl-4-pentenoic acid ethyl ester in the form of a diastereoisomeric mixture having a melting point of 670.

tr c) E-2-formylamino-4-methyl-5-diisopropylphosphon -3-pentenoic acid ethyl ester (3) Under an argon atmosphere, 18.6 ml of thiony! bromide are added dropwise t at 20°, within a period of 5 minute3, to a solution of 40.20 g of crude 2-formylamino-3-hydroxy-4-methyl-4-pentenoic acid ethyl ester in 600 ml of 1,2-dichloroethane (slight cooling). After stirring for two hours at room temperature, 400 ml of water are added, the first 50 ml being slowly added dropwise. The mixture is stirred thoroughly for a further t 15 minutes to complete the reaction. The organic phase is separated off and washed three times with ice-water and once with ice/saturated S potassium bicarbonate solution (pH approximately Drying over sodium sulphate and removal of the 1,2-dichloroethane by distillation in vacuo at 350 yields the crude bromide as intermediate, to which 160 ml of triisopropyl phosphite are added at room temperature, ard the mixture is then stirred at 750 (bath temperature) under a partial vacuum (approximately 13 kPa) for 17 hours. The excess triisopropyl phosphite and other volatile by-products are then distilled off under a high vacuum (bath temperature Chromatography of the residue on ten times the amount by weight of silica gel (particle size 0.04-0.06 mm) using ethyl acetate as eluant yields E-2-formylamino-4-methyl-5-diisopropylphosphono-3pentenoic acid ethyl ester in the form of a light-yellow honey, IR (CHa2C1): 3410 1740 (CO ester); 1690 (CO amide); 1235 980-1015 28 d) E-2-amino-4-methyl-5-phosphono-3-pentenoic acid ethyl ester (4) 56.7 ml of trimethylbromosilane are added dropwise within a period of minutes at 200 to a solution of 25.42 g of E-2-formylamino-4-methyl-5diisopropylphosphono-3-pentenoic acid ethyl ester in 102 ml of dry dichloromethane. After stirring at room temperature for 20 hours, 102 ml of ethanol are added dropwise within a period of 15 minutes, and the whole is stirred for a further 20 hours. The clear reaction solution is then completely concentrated by evaporation in vacuo. The residue is concentrated by evaporation a further three times in each case after the addition of 100 ml of toluene. The oily residue is dissolved in 102 ml of ethanol, and a solution of 102 ml of propylene oxide in 102 ml of ethanol is added dropwise thereto. The product, obtained in crystalline form, is S. filtered off after 2 hours (room temperature) and washed with ethanol and ether. After drying (800, 4 hours) under a high vacuum, E-2-amino-4- S* methyl-5-phosphono-3-pentenoic acid ethyl ester is obtained in analytically pure form, m.p. 2120 (decomp.).

*9 S Example 2: E-2-amino-4-methyl-5-phosphono-3-pentenoic acid ethyl ester a) E-2-formylamino-4-methyl-5-dimethylphosphono-3-pentenoic acid ethyl ester (1) 100.5 g of 2-formylamino-3-hydroxy-4-methyl-4-pentenoic acid ethyl ester are dissolved in 1.5 litres of dichloroethane, and then 47 ml of thionyl bromide are added dropwise at 20-25° and the mixture is stirred at room temperature for one hour. 750 ml of water are added to the reaction mixture, which is then stirred vigorously for 10 minutes. The organic phase is separated off, extracted with 1 litre of ice-water, 1 litre of IN potassium hydrogen carbonate solution and a further 1 litre of icewater, dried over magnesium sulphate and concentrated by evaporation.

ml of trimethyl phosphite are added directly to the resulting E-5-bromo-2-formylamino-4-methyl-3-pentenoic acid ethyl ester, a yellow oil, and the mixture is stirred at a bath temperature of 70' and approximatey 15 kPa for 15 hours. The reaction mixture is degassed for minutes under a water-jet vacuum and for one hour under a high vacuum at 40-50°. The resulting product is taken up in 600 ml of water and extracted three times with 500 ml of ethyl acetate each time. The 29 combined organic phases are washed twice with 300 ml of water each time.

All the aqueous phases are combined, saturated with sodium chloride and extracted three times with 500 ml of dichloromethane each time. The combined organic phases are dried over magnesium sulphate and concentrated by evaporation. The product is chromatographed over silica gel (ethyl acetate/isopropanol In this manner, E-2-formylamino-4methyl-5-dimethylphosphono-3-pentenoic acid ethyl ester is obtained in the form of a yellow oil, 'H-NMR (DMSO): 1.82 3H, 4-CH3); 2.69 2H); 5.03 1H); 5.32 1H).

b) E-2-amino-4-methyl-5-phosphono-3-pentenoic acid ethyl ester (2) 16.9 g of E-2-formylamino-4-methyl-5-dimethylphosphono-3-pentenoic acid .o ethyl ester are dissolved in 80 ml of dichloromethane under a nitrogen atmosphere, and 30 ml of trimethylbromosilane are added dropwise at approximately 250 within a period of 30 minutes. The mixture is stirred a*aa S, at room temperature for 20 hours, and then 80 ml of ethanol are added a dropwise at approximately 25° within a period of 30 minutes. The mixture is then again stirred at room temperature for 22 hours and is then concentrated by evaporation. The residue is dissolved in 80 ml of ethanol, and 80 mi of propylene oxide in 80 ml of ethanol are added dropwise with slight cooling. The mixture is stirred at room temperature for one hour to complete the reaction, filtered and washed with ethanol Sr', and ether. In this manner there is obtained E-2-amino-4-methyl-5phosphono-3-pentenoic acid ethyl ester, m.p. 215-217° (decomp.).

Example 3: E-2-amino-4-methyl-5-phosphono-3-pentenoic acid ethyl ester a) E-2-formylamino-4-methyl-5-di(2-chloroethyl)phosphono-3- pentenoic acid ethyl ester (1) 8.2 g of E-5-bromo-2-formylamino-4-methyl-3-pentenoic acid ethyl ester and 19 ml of tris-(2-chloroethyl)-phosphite are stirred at a bath temperature of 70° for 20 hours. The resulting mixture is chromatographed on silica gel using ethyl acetate and ethyl acetate/isopropanol as eluant, and the producc is crystallised from ethyl acetate/diethyl ether.

In this manner there is obtained E-2-formylamino-4-methyl-5-di(2-chloroethyl)phosphono-3-pentenoic acid ethyl ester, m.p. 47-490.

30 b) E-2-amino-4-methyl-5-phosphono-3-pentenoic acid ethyl ester (2) In a manner analogous to that described in Example 2, using 3 g of E-2formylamino-4-methyl-5-di(chloroethyl)phosphono-3-pentenoic acid ethyl ester, there is also obtained E-2-amino-4-methyl-5-phosphono-3-pentenoic acid ethyl ester, m.p. 2150 (decomp.).

Example 4: E-2-amino-4-phosphonomethyl-3,6-heptadienoic acid a) 2-methylene-4-pentenealdehyde (1) 24.5 g of a 37 aqueous formaldehyde solution are added to a mixture of 14.7 g of piperazine, 20.5 g of glacial acetic acid and 21.28 g of water, and the whole is stirred at room temperature for 10 minutes. While continuing stirring, 25.35 g of 4-pentenealdehyde are added, and the f reaction mixture is heated at 750 for 3 hours. After cooling to room 1 temperature, the organic phase is separated off and the aqueous phase is t extracted three times with 50 ml of diethyl ether each time. The combined organic phases are washed three times with 50 ml of a saturated sodium bicarbonate solution each tim dried over magnesium sulphate and concen- 't t trated by evaporation in vacuo. Fractional distillation of the residue r yields 2-methylene-4-pentenealdehyde in the form of a colourless oil, b.p. 65°/6.6 kPa.

b) 5-[2-(1,4-pentadienyl)]-2-oxazoline-4-carboxylic acid methyl ester (2) By reaction of isocyanoacetic acid methyl ester with 2-methylene-4pentenealdehyde in toluene in a manner analogous to that described in Example 1, and after subsequent purification by column chromatography (silica gel, ethyl acetate/hexane 5-(2-(1,4-pentadienyl))-2-oxazoline-4-carboxylic acid methyl ester is obtained in the form of a colourless oil, IH-NMR (CDC1I): 2.80 2H, CH 2 4.45 (dd, 1H, 5.82 1H, 7.00 1H, 8.1 g of 5-(2-(l,4-pentadienyl))-2-oxazoline-4-carboxylic acid methyl ester are dissolved in 20 ml of tetrahydrofuran, and 10 ml of water are added thereto. The reaction mixture is stirred at 750 for 1.5 hours and, after cooling, is concentrated by evaporation in vacuo. Crystallisation

I

-31of the resulting residue from isopropanol/hexane yields 2-formylamino-3hydroxy-4-methylene-6-heptenoic acid methyl ester in the form of a diastereoisomeric mixture, m.p. 75-770.

c) E-2-formylamino-4-bromomethyl-3,6-heptadienoic acid methyl ester (3) g of 2-formylamino-3-hydroxy-4-methylene-6-heptenoic acid methyl ester in 200 ml of dry tetrahydrofuran are cooled to and 20 ml of 1 ,5-hexadiene are added thereto. 9 ml of thionyl bromide are added slowly dropwise in such a manner that the reactioni temperature does not exceed When the addition is complete, the reaction solution is heated to 0' within a period of approximately 3 hours and is stirred at that temperature for 3 hours. The solution is then poured onto 300 ml of a cold saturated sodium bicarbonate solution and extracted with diethyl ether. The organic extracts are washed with saturated sodium xx' chloride solution, dried over magnesium sulphate and concentrated by evaporation in vacuo. Purification by column chromatography (silica gel, ethyl acetate/hexane 1:1) yields E-2--formylamino--4-bromonethyl-3 ,6-heptadienoic acid methyl ester in the form of a colourless oil, IH-NMR (CDCl 3 3.20 2H, 4.00 2H, CHzBr).

4 P' E- 2-f ormylamino-4 -die thylphosphonome thyl- 3, 6heptadienoic acid methyl ester (4) 3.7 g of E-2-formylamino-4-bromomethyl3,6-heptadienoic acid methyl ester are dissolved in 37 ml of triethyl phosphite, and the mixture is heated at 75' for 8 hours. Excess triethyl phosphite is then distilled off under a high vacuum. Purification by column chromatography (silica gel, methanol/ethyl acetate 1:10) yields E-2-f ormylamino-4-die thy lpho sphonomethyl-3,6-heptadienoic acid methyl este~r in the form of a colourless I oil, IH-NxMR (CDC13): 2.54 2H, P-Cl! 2 3.10 (in, 2H, C(5)-11); 5.10 (mn, 2H, 5.37 111, 5.74 (in, IH, e) E-2-amino-4-phosphononethyl-3, 6-heptadienoic 0.74 g of E-2-formylamino-4-diethylphosphonoinethyl-3, 6-beptadienoic acid methyl ester is dissolved in 12 ml of dichloromethane, and 0.7 ml of t rime thyliodos ilane is added dropwise thereto. After Atirring at room temperature for 4 hours, 1N sodium thiosulphate solution is added until 32 the colour of the reaction solution becomes lighter. 10 ml of a hydrochloric acid solution are then added to the reaction mixture, which is then stirred at room temperature for 30 minutes. The aqueous phase is separated off, washed twice with 20 ml of dichloromethane each time, and concentrated by evaporation in vacuo. The residue is dissolved in 10 ml of 4.5N hydrochloric acid, stirred at room temperature for 16 hours, and then concentrated by evaporation in vacuo. The residue so obtained is taken up in 40 ml of ethanol and filtered until clear, and then 10 ml of propylene oxide/ethanol are added dropwise. The resulting white precipitate is filtered off and purified by column chromatography (Dowex x 8/H20). Concentration yields E-2-.amino-4-phosphonomethyl-3,6-hepta- 0,«t dienoic acid in the form of a white crystallisate, m.p. 154-1570, 'H-NMR

(D

2 2.64 2H, P-CH2); 3.15 2H, 5.20 2H, *4 5.50j (dd, 1H, 5.90 1H, c Example 5: (2R)-2-amino-4-methyl-5-phosphono-3-pentenoic acid 4 4 4, a) (L)-N-tert.butoxycarbonyl-serine-N-methoxy-N-methyl 541.6 ml of N-methylmorpholine are added within 27 minutes at -20° to Q. -25° to ay solution of 1 kg of (L)-N-tert.butoxycarbonyl-serine in 1 litre of tetrahydrofurane. The reaction mixture is stirred for minutes at this temperature. Then 699.6 ml of chloroformic acid iso- Sr butyl ester and subsequently 445,8 ml of N-methoxy-N-methylamine are added within 42 and 40, resp. minutes. The reaction mixture is allowed to warm to room temperature and evaporated to dryness. The residue is dissolved in 3 litres of ethyl acetate. The solution is extracted with litres of 2n-hydrochloric acid and subsequently with 3 1 of saturated aqueous sodium hydrogencarbonate solution. The water-layers are extracted with 3 1-litre ethyl acetate. All organic extracts are combined, washed with 2 litrea of saturated sodium dichloride solution, dried over magnesium sulfate an evaporated at 500 to dryness. The residue is triturated with 3.5 litres of hexane with ice-cooling. The resulting white precipitate is filtrated off, washed with 1 1 of hexane and dried under reduced pressure to yield 781 g 2, m.p, 116-117°; calculated for C1H10oN2Os C 48.38 H 8.12 N 11.28 found C 46.28 H 8.02 N 11.32

I

33 b) (L)-3-tert.butoxycarbonyl-2,2-dimethyl-oxazolidine-4-carboxylic acid- N-methoxy-N-methyl-amide (2) A mixture of 781 g of 1, 3.3 litres of acetone dimethylacetal and 42 g of pyridinium(toluol-4-sulfonate) are warmed to 720 and refluxed for 17 hours. After addition of additional 20 g of pyridinium(toluol-4sulfonate) heating to boil is continued for additional 9 hours while gradually destilling of approximately 750 ml of solvent and adding 700 ml of acetone dimethylacetal. All volatile constituents we destilled off.

The residue is dessolved in 2 litres of diethyl ether and extracted twice with 1 litre and 0.5 litre of n-hydrochloric acid, once with 0.3 litre of us saturated sodium hydrogencarbonate solution and once with 0.3 litre of saturated sodium chloride solution. The aqueous extracts we re-extracted twice with 0,5 litre either time of diethyl ether. All organic extracts it t S are combined, dried over magnesium sulfate and evaporated to dryness. The residue is dissolved hot in a 9:1-mixture of hexane and diethyl ether.

After addition of additional 600 l of hexane and 50 ml of diethyl ether, the reaction mixture is cooled down while diluting a crystallisation with 1,1 litre of hexane. The precipitate formed is filtered off, washed with hexane and dried under reduced pressure at 400 yielding 640 g of 2; S m.p. 67-680; calculated for C3HatiNa05 C 54.15 H 8.39 N 9.72 found C 53.96 H 8.37 N 9.91 c) (4S)-2,2-dimethyl-4-formyl-3-oxazolidine-carboxylic acid tert.butyl ester (3) 2.53 g of lithium aluminium hydride are added with cooling to maintain a temperature of 5 to 150 to 28.8 g of 2, dissolved in 350 ml of diethyl ether. After stirring at 5° for 1.5 hours a solution of 5.77 g of sodium hydrogen sulfate is added slowly to keep the reaction temperature at 150 (40 minutes). The suspensions formed is filtered clear and tho solid portion is washed with ether. The filtrate is washed, with cooling, twice with 200 ml each of n-hydrochloric acid, twice with 150 ml each of 5 sodium hydrogencarbonate solution and dried with 100 ml of saturated sodium chloride solution. The aqueous extracts are re-extracted with ether and all organic extracts are combined, dried over sodium sulfate and evaporated. The residue is distilled at 0.4 ml yielding 17.78 g of 3; r 34 b.p. 85-900, -94 CHC1 3 calculated for CIH 1 9 gNO4 C 57.63 H 8.35 N 6.11 0 27.91-%; found C 57.59 H 8.54 N 6.17 0 27.74 d) 3-((4'R)-N-tert.-butoxycarbonyl-2',2'-dimethyl-4'-oxazolidinyl)-2methylpropenoic acid ethyl ester (4) A solution of 39.5 g of (4S)-2,2-dimethyl-4-formyl-3-oxazolidinecarboxylic acid tert.-butyl ester 3 in 200 ml of dichloromethane is added dropwise within a period of 2 hours to a solution of 68.7 g of 1-ethoxycarbonylethylidenetriphenylphosphorane in 900 ml of dichloromethane.

After stirring at room temperature for 6 hours, the mixture is cooled to 10 and there are then added dropwise within a period of 15 minutes 530 ml of a 10 aqueous sodium hydrogen phosphate solution. After S stirring at 15' for 30 minutes, the organic phase is separated off and the aqueous phase is extracted with 250 ml of dichloromethane. The S organic phases are dried over magnesium sulphate and concentrated by S evaporation. The residue is stirred with 70 ml of ether, The suspension It is filtered and the filtration residue is washed with ether. The filtrate is concentrated by evaporation and the residue is separated by chromatography on silica gel. Elution with hexane/ethyl acetate 9:1 yields, in addition to 2.32 g of cis-isomer and 2.21 g of mixed fraction (cis/trans 38:62), 45.4 g of 4. IH-NMR (60 MHz, CDC1 3 transisomer): inter alia 4.7 ppm 6.7 ppm J-9, IH-NMR (60 MHz, CDCl 3 cis-isomer): inter alia 5.2 ppm (m 6.08 ppm J=7, e) (4R)-2,2-dimethyl-4-(3'-hydroxy-2'-methylprop-l'-enyl)-oxazolidine-3carboxylic acid tert.-butyl ester 389 ml of a I molar solution of diisobutylaluminium hydride in hexane are Sadded within a period of 15 minutes to a solution, cooled to 30, of 48.7 g of 4 in 1 litre of dry diethyl ether. The temperature of the mixture is allowed to rise to 11°, and there are then added thereto, while cooling with ice, 100 ml of ethyl acetate followed by 50 ml of 2N sodium hydroxide solution. The temperature of the mixture is allowed to rise to approximately 28°, without cooling, then a further 7 ml of 2N sodium hydroxide solution are added. The mixture is stirred at room temperature for 15 hours, and then sodium sulphate is added and the whole is filtered. Concentration, of the filtrate by evaporation yields 42.1 g of crude 2. A sample (0.97 g) is purified by chromatography on 40 g of silica gel. Elution with hexane/ethyl acetate 3:1 yields 0.74 g of IH-NMR (300 MHz, DMSO-d 6 inter alia 3.52 (dxd, J=9Y and, 3) and 4.02 (dxd, J-9 and 6) 3.78 (in, 4.54 (mn, 4.81 J-6, OH); 5.33 J=9, f) (4R)-2,2-dimethyl-4-(3'-bromo-2'-methylprop-1 '-enyl)-oxazolidine-3carboxylic acid tert.-butyl ester (6) 47.6 g of triphenylphosphino are added at 0' to a solution of 41.0 g of and 60,2 g of tei'rabroiomethane in 1 litre of dry diethyl ether. After room, temperature forz 17 hours. 20 g of tetrabromomethane and 15.9 g of triphenyiphosphine are added, And the mix~ture is stirred at rooq temperature for 2 hours, The white suspension is filtered and the liltration residue is washed with ether. The residue remaining after the filtrate has been concentrated by evaporation is chromatographed on 0.9 kg of silica gel. Elution with hexcane/otbyl acetate 9:1 yields 30.59 g of 6, 62-6511c. fIH-NIR (300 MHz, DMSQ-d6): inter alia 3.55 (dxd, J=9 and 2) and 4.04 (dxd, J-9 and 6) 4.15 (mn, 4.49 (in, 5.65 J=9, g) (4)-,2dm hl4 3 -iotylh poo2-etypo- '-enyl) -oxazolidina-3-carboxylic acid tert.-butyl ester~ (2) A solution of 13.4 g of A in 70 ml of tritnethyl phosphite is stirred, At 800 for 15 hours. The exces, phosphi~te is evaporated off at 24 mnbar.

Drying of the residue under a high vacuum yield's 14.3 g of crude 7.

I 1 IH-NI4R (300 MHz, DMSO-d6): inter alia 2.63 J-23, 3.59 h) (2R)-5-dimethylphosphano-lhydroxy-4-mothyl-3-peften. 2-yl)carbamic acid tert.-butyl Pester (A) 7 g of AmberlystO' 115 (11+ form, 20-50 mesh) are added to a solution of 14.0 g of 7. in 250 ml of mnethanol. The ixiture is stirred at room temperature for 17 hours and filtered, and the filtrate is concentrated 36 by evaporation. Chromatography of the residue on 0.33 kg of silica gel using ethyl acetate/methanol 10:1 as eluant yields 10.6 g of 3. IH-NMR (300 MHz, DMSO-d6): inter alia 4.60 J-6, OH), 6.67 J-7, NH).

i) (2R)-2-tert.-butoxycarbonylamino-5-dimethylphosphono-4- methyl-3pentenoic acid (9) i,a) Oxidation with chromosulphuric acid To a solution of 0.323 g of 8 in 10 ml of acetone there is added 0.77 ml of a solution that is 3.25 molar in chromium trioxide and 5.29 molar in sulphuric acid. The mixture is stirred at room temperature for 40 minutes S and then there are added 2 ml of isopropanol followed by 50 ml of ethyl S acetate. 0.1 g of active carbon is then added to the mixture. After 0 10 minutes, the mixture is filtered and washed with 50 ml of ethyl acetate. The filtrate is extracted three times with 50 ml of 10 sodium hydrogen carbonate solution each time, The aqueous phase is extracted t. twice with 40 ml of ethyl acetate each time, acidified to pH 1 using 2N 9 hydrochloric acid, and then extracted three times with 70 ml of ethyl acetate each time. The organic extracts are washed with saturated sodium chloride solution, dried over magnesium sulphate and concentrated by evaporation. Chromatography on 8 g of silica gel using chloroform/ methanol/acetic acid 18:1:1 as eluant yields 65 mg of 9, 1

H-NMR

(300 MHz, DMSO-d 6 1.37 (CH 3 3 1.82 J-2, CH 3 2.63 (d, J-22, 3.61 J-l1, (CHab0)PO); 4.62 J=8, 5.25 7.18 J-8, NH); 11.7-12.5 (CO 2

H).

i,b) Oxidation with oxygen/platinum To a solution of 0.66 g of 8 and 0.2 g of sodium hydrogen carbonate in ml of water and 2 ml of dioxan there is added a suspension of platinum prepared by hydrogenacion of 313 mg of platinum oxide in 50 ml of water.

In a cylindrical aipraratus, oxygen is passed through the mixture from bottom to top at 55" by means of a glass frit, with vigorous stirring.

The mixture is filtered and washed with water, and the filtrate is extracted five times with 100-150 ml of ethyl acetate each time. Concentration of the extracts by evaporation yields 220 mg of educt 5. 1 g of AmberlystO 15 (strongly acidic) is added to the aqueous phase, which is -37then filtered and concentrated by evaporation in vacuo at 40'. Purification as in f,a) yields 1,56 mng of 9. 'H-NIIR (300 MHz, CDC1 3 1.43 (s,

(CH

3 3 1.96 J-3 Hz, CH 3 2.55 and 2.71 (2 clxd, J=22 and 3.75 a nd 3.76 (2 d, J=11, 2 OClia); 4,97 (mn, 5.25-5.45 (in, NH and I I I I I I I I*I~ I II I I I I I II

II

It I I It I 11 I I I I II j) (?R)-2-amino-4-methyl-5-phosphono-3-pentenoic acid 0.71 mi of trimethylsilyl bromide is added at 0' to a solution of 123 mg of 9 in 3 ml of dichioromethane. After stirring at 00 for 4 hours, 20 ml of water are added. After 30 minutes, the dichiopromethane phase is separated, off and washed three times with 15 mli of water each time, The aqueoits phases are extracted three times with 20 ml of dichloromethane each time and concentrated by evaporation in vacuo. The residue is dissolved in 10 ml of 5N hydrochloric acid and is then stirred for 48 hours, diluted with 20 ml of water and ex~tracted three times with 20 ml of dichloranethane each time. The aqueous phase is concentrated by evaporation in vacuo, and the residue is dried tinder a hiLgh vacuum and dissolved in 3 ml of ethanol, and then approximately I ml of propylene oxide is added dropwise thereto. The suspension is filtered. Washing o~f the filtration residue with ethanol and drying under a high vacuum at room temperature yields 62 mg of 1, m-p, 165%0 (decomposition).

In order to analype the purity of the enantiomer) a sample is derivatised tn- he amide with (R)-(+)-"mothoxytriflooromethylphenylacetic acid chloride. 1 -NOR analysis (300 MHz) by integration of the 0CH3 signals gives 95 %C (29)-isomet (3.44 ppm) and 5 (2S)-isomor (3.37 ppm).

Example-6: L7?R)-2-amino-4-methyl-5-phosprhono-3-pontenoic acid ethyl ester a) (4R)-,2-dimethyl-4-(3'-diisopropypophono-2'-methyl- prop-11-enyl)oxazolidine-3-cmrboxylic acid tort.-'butyl ester (1) A solution of 6.68 g of bromide according to Example Sf in 14.8 m! of dry triisopropyl phosphite is boated at 70%C for 17 hours under a piroasure of Il -38 100 mbar. The mixture is concentrated by evaporation at 0.4 Chromatography on 350 g of-silica gel (eluant hexane/ethyl acetate 1:1) yields 8.28 g of 1, Rf value =0.077, b) 2 R) -5-dii sopropylpho sphono- -hyd roxy- 1;me thy 1-3 -ti-,nt en-2-yl) carbamic acid tert. -butyl ester (2) 2.25 g of AniberlystO 15 (H +form, 20-50 mesh) are added to a solution of 4.49 g of phosphonic acid ester 1 according a) in 100 ml of methanol, The mixture is stirred at room temperature for 2 dayq and is filtered, and the filtrate is copcentrated by evaporation. Chromatography of' the residue on 125 g of silica gel (eluant ethyl acetate/methanol 20*,1) yields 2.44 S of 2.

0) (2R)-2-tert butoxycarbonylamino-5-diisopropylphosphono- 4 -mthyl-3 '4 peotenoic acid S To a solution of 1,6 g of alcohol 2 accordl.zag to b) in 60 ml of acetone 09 4k there are added at 0-5* 3.3 ml of a solution that is 3.25 molar in chromium(VI) oxide and 5,219 molar in sulphuric acid4 The mixture is stirred at 0' for 6 hours q-8 at room temperature for 12 hours. After the 4, addition of 5 ml of, ioopropanal and 40 ml of 20 sodium chloride solution, the nvxture is stirred for 10 minutes and is them extracted contimuously with methyl aqetato for 15 hours in a Kutacher-Steudel apparatus. The organic phase is dried over sodium suilphate and concentrated by evaporation,, and the residue 1,s chromatographed on 75 g of hexane/ethyl 4cotate/acetic acid 16,110:1. This yie'lds 0.92 g, of 3, [C')D a -94.5' (c 1.2, Cfl0l3). IH-NMR, (300 MHz, CDQl3): 1.2-1.3 (4d, (2-propo)z); 1.4 (CI13)3C0); 1.95 J.3, 013-0(4)); 3.5 and 3.62 (2 dxd, J-23 and 15, 211-C(5)); 4,66 (mn, (2-propo)2); 4.92 (mn, 5,30 (in, 5.42 J-7, NH); 9.0-10.0 (broad, COU).

d) (2R)-2-tert butoxycarbonylaminin5-dlisopropylphosphono- 4 -inethyl-3 pentenoic, acid ethyl enter (A) 0.09 g of I -amino- I -chloro-N 2-trimo thylpropene is added at 0-5' to a solution, of 0.2 g of acid .3 according to c) in 15 ml of dry dichloromethane. After stirring f~or 30 minutes at 00f 0.4 g of pyridime in 5 ml of ethanol is added. The mixture is stirred further at 00 for 90 minutes 39 and at rocm temperature for 15 hours, and is then diluted with 20 ml of dichloromethane and washed- twice with 20 ml of water each time. The organic phase is dried using sodium sulphate, concentrated by evaporation and chromatographed on 25 g of silica gel. Elution with ethyl acetate/ methanol 10:1 yields 0.12 g of 4. '1-.N?4R (300 MHz, CDC13): 1.2-1.4 (in, 2(pili)2CHO, OCH 2 1.5 CH)0) 1.98 J=3, CH3-C(4); 2.55 J=23, 4.2 (in, CH 3 CgHp0); 4.69 (in, 2 (CHa 2 CHO); 5.0 (mn, 5.16 (in, NH).

e) (2R)-2'-amino-4-tpethyl-5-phosphono-3.-pentenoic acir' ethyl 0.11 ml of triniethylpllyl broit.. is added at 0' to a solution of 0.1 g of est- 4 according to d) in 10 ml of dichloromethane. The mixture .s stirred at 00 for 4 hours and at room temperature for 15 hours. 20 ml of water are added, the mixture is stirred for 15 minutes, and then the aqueous phase is separated off and the water is evaporated off under a high vacuum, The residue is dissolved twice in 5 ml of ethanol each time, concentrated by evaporation and again dissolved in 5 ml of ethanol.

ml of propylene oxide is added. The precipitate is filtered off, washed with ethanol and dried under a high vacuum for 15 hottrs; 48 mng of In order to analyse the p rity of the enantioner, a sample is derivatised to the amnide dimethyl estbr with (R)-(+)-methoxytrifluoromethylphenylacetic ac~id chloride foll('.ged by diazoinethane. 1H-Nl1R analysis (300 MHz) by integration of the 03 signals gives 97 (2R)-isomer (3.5 ppm) and S, 3 (2S)-isoiner (3.31 ppm)., KjnpRLe 7:(R-2-amino-.4-methyl-7-phosphono-3-heptenoic acid a) (4R)-2,2-dimethyl-4-(1'-hydroxy-2'-methiylprop-2'-iny)-oxazolidine- 3-carboxylic acid tort 1 -butyl ester (1) ml of a 1.1 molar solution of .tsopropenylmagnesium bromide are added dropwise at 0-5" within a period oil 25 'minutes to a solution of 6.9 g of (4s)-2.,2-diinethiyl.

4 -foriyloxagolidine-3-.carboxylic acid tert.-butyl ester (according to Example 50)) iri 60 ml of ciry tetrahydrofuran. The mixture is stirred, at for 45 minutes, allowed to warm up to room temperature r

I:

40 and cooled again to 100, and then 90 ml of buffer solution (1 molar, phosphate, pH 7) are added. The mixture is filtered and the filtrate is extracted twice with 100 ml of ethyl acetate each time. The organic phase is washed twice with 50 ml of water each time and with saturated sodium chloride solution, and is dried with sodium sulphate. Removal of the solvent by evaporation yields 8 g of 1, a diastereoisomeric mixture.

Separation may be effected by chromatography on silica gel using hexane/ ethyi acetate 4:1 and yields crystalline (1'S)-threo-epimer (Rf value: 0.2) and (1'R)-erythro-epimer (Rf value: 0.16) in a ratio of approximately 1:2.

b) (4R)-4-(1'-acetoxy-2'-methylprop-2'-enyl)-2,2-dimethyl-oxazolidine- 3-carboxylic acid tert.-butyl ester (2) s* 60 ml of acetic anhydride are added dropwise at 0-5' within a period of 10 minutes to a solution of 15.6 g of the epimer mixture according to a) in 60 ml of pyridine. The mixture is stirred at room temperature for hours and diluted with 0,5 litre of diethyl ether, and then 200 ml of 2N hydrochloric acid are added while cooling with ice. The organic phase is washed with 250 ml of 2N hydrochloric acid and twice with 200 ml of S* 10 sodium carbonate solution each time. Drying over sodium sulphate and C, removal of the solvent: by evaporation yields 15.4 g of 2.

c) (4R)-4-(4'-carboxy-2'-methylbutenyl)-2,2-dimethyl-oxazolidine-3carboxylic acid tert.-butyl ester (3) 34.5 ml of a 1.6 molar solution of butyllithium in hexane are added at 0° to a solution of 5.25 g of diisopropylamine in 200 ml of dry tetrahydrofuran. The mixture is cooled to -75°C and a solution sf 15 g of acetate 2 according to b) in 100 ml of tetrahydrofuran is added dropwise within a period of 10 minutes, and after 5 minutes a solution of 8 g of tert.- 2 butyldimethylsilyl chloride in 30 1 of 1,3-dimethyl-3,4,5,6-tetrahydro- 2-(1H)-pyrimidinone is added. The mixture is allowed to warm up to room temperature and is then heated under reflux for 2 hours and cooled to room temperature. 230 ml of 45 ammonium fluoride solution are added, and the whole is stirred at room temperature for 20 hours and is then concentrated by evaporation. 150 ml of IN sodium hydroxide solution are added, while cooling with ice, to the oily residue which is obtained 41 after concentration of the organic phase by evaporation, and the mixture is extracted twice with 200 ml of dichloromethane each time. The aqueous phase is acidified with 300 ml of 20 citric acid solution and is extracted three times with 300 ml of dichloromethane each time. The organic phases are washed with 20 sodium chloride solution, dried over sodium sulphate and concentrated by evaporation. Chromatography of the residue on 50 g of silica gel using hexane/ethyl acetate 1:1 as eluant yields 11 g of solid 3.

d) (4R)-4-(4'-4arbaethoxy-2'-methylbutenyl)-2,2-dimethyl-oxazolidine-3carboxylic acid tert.-buty. ester (4) *4 d,a) Starting from the acid 3 46 3.9 ml of l-amino-l-chloro-N,N,2-trimethylpropene are added dropwise S" within a period of 10 minutes to an ice-cooled solution of 7.8 g of carboxylic acid 3 according to c) in 100 ml of dry dichloromethane. After S 30 minutes at 00, a solution of 2.2 g of pyridine in 80 ml of ethanol is added within a period of 20 minutes. After stirring at room temperature for 12 hours, the mixture is diluted with 100 itl of dichloromethane and washed twice with 100 ml of water each time, The organic phase is dried over sodium sulphate and concentrated by evaporation. Chromatography of the residue on silica gel using hexane/ethyl acetate 10:1 yield. 6.5 g of S ester 4, [a]D +6.17° CHCl 3 Ci 8 H31NOs, calculated: C 63.32 H 9.15 N 4.10 found; 0 63.4 H 9.2 N 4.5 d,b) Starting from the epimer mixture 1 A solution of 8 g of alcohol 1 according to a) and 0.05 ml of propionic acid in 10.5 ml of orthoacetic acid triethyl ester is heated at 135-140' for 14 hours, with ethanol slowly being distilled off. The whole is a concentrated by evaporation at 40' under a high vacuum. Chromatography of the residue on silica gel using hexane/ethyl acetate 10:1 yields 8 g of 4.

i i 42 e) (4R)-2,2-dimethyl-4-(5'-hydroxy-2'-methylpent-l'-enyl)-oxazolidine- 3-carboxylic acid tert.-butyl ester 1.61 g of lithium aluminium hydride are added in portions at 0° to a solution of 14.5 g of 4 according to d) in 250 ml of absolute diethyl ether. The mixture is stirred at 0-20 for 18 hours, and a solution of 5 g of potassium hydrogen sulphate in 60 ml of water is added while cooling with acetone/dry ice. The mixture is filtered and washed four times with 200 ml of diethyl ether each time. The organic phase is washed three times with 80 ml of IN hydrochloric acid each time, three times with ml of saturated sodium bicarbonate solution each time, and twice with 200 ml of saturated sodium chloride solution each time, and is then dried over sodium sulphate and concentrated by evaporation. Chromatography on silica gel using hexane/ethyl agetate 1:1 yields 11.3 g of 5, C 16 HZgNO4, calculated: C 64.19 H 9.77 N 4,68 found: C 63.6 H 9.8 N 4.7 f) (4R)-4-(5'-bromo-2'-methylpent-l'-enyl)-2,2-dimathyl-oxazolidine-3carboxylic acid tert.-butyl ester (6) 4.87 g of tetrabromomethane, 3.85 g of triphenylphosphine and 0.6 ml of pyridine are added at 0-2° to a solution of 4.4 g of alcohol 5 according S to e) in 200 ml of dichloromethane. After 12 hours at a further 1 g of tetrabromomethane and 1 g of triphenylphosphine are added and the mixture is stirred at 0° for 6 hours. The mixture is concentrated by evaporation, taken up in ethyl acetate, filtered and concentrated.

Chromatography on silica gel using hexane/ethyl acetate 10:1 yields 4.5 g of 6, C1 6 Ha2NO 3 Br; calculated: C 53.04 H 7.79 N 3.87 Br 22.06 found: C 53.1 H 7.7 N 3.9 Br 21.6 g) (4R)-2,2-dimethyl-4-(2'-methyl-5'-diisopropylphosphono-pent-l'-enyl)o, azolidine-3-carboxylic acid tert.-butyl ester (7) A solution of 10,9 g of bromide 6 in 22 ml of triisopropyl phosphite is heated at 135-1400 for 24 hours at 100 mbar. The excess reagent is evaporated off at 0.1 mbar/60 0 Chromatography of the residue on silica gel using hexane/ethyl acetate yields 10.7 g of 7.

-I

43 h) (2R) -1-hydroxy-4- nethyl-7-diisopropylphosphonohept-3- en-2-yl) carbamic acid tert.-butyl ester (8) 3 g of AmberlystO 15 (H form) are added to a solution of 3 g of 7 according to g) in 100 m-l of ethanol. The mixture is stirred at room temperature for 20 hours, filtered, concentrated by evaporation and chromatographed on 50 g of silica gel. Elution with ethyl acetate/ methanol 10:1 yields 2.3 g of 8, (c1l, CHCla). CjqH 38 N0 5

P;

calcu~ated: C 56.0 H 9.4 N 3.44 7.6 found: C 55.4 H 9. N 3. 4 P 7 .3 i) O2R) -2-te rt bu toxy Qarbonylamino- 4-me thy1- 7 -dii sopropylpho sphono- 3 heptenoic acid (9) i,a) OIxidation wi-,h ch-tocic acid 0.84 ml of a solution which is 3,25 molar in chromium trioxide and 5.29 molar in sulphuric acid is added dropvise at 0-5' to a solution of g of alcohol 8 according to h) in 15 ml of acetone. The mixture is stirred at 0 0 for 30 minutes and at room temperature for 35 minutes, and then 4 ml of isopropanol, 80 ml of ethyl acetate and 30 ml of 20 sodium chloride solution are added thereto, and the mixture is filtered. The S aquieous phase is extracted three times with 20 ml of ethyl acetate each time, The organic. phase is dried over sodium sulphate and concentrated by evaporation. Chromatography on 20 g of silica gel using hexane/ethyl acetate/acetic acid 16:10:1 yields 0.34 g of 9, D 0 35.25* (c-1.39, 011013), 3 C-NMR (75 MHz, CDCl 3 173.8 (CO2H); 155.0 (OCON); 140.4 121.1 79.5 (OC(CH3)3); 70.3 (OCH); 52.1 39.7 J=18, 28.3 ((CH3) 3 25.7 J=142, CM7); 24.0 ((CH 3 2 CH); 20.2 J-5, i,b) Oxidation with platinum/xvgen To a solution of 3 g of alcohol 8 according to h) in 105 ml of dioxan there is added at 550 a suspension of platinum in 45 ml of water prepared by hydrogenation and degassing of 1 g of platinum oxide in 45 ml of water. Oxygen is passed through the mixture at 55-60" with vigorous stirring (approximately 1900 rpm). The mixture is filtered through Celita'O and w.ashed twice with 80 ml of water each time, and the filtrate

J/-

44 is concentrated by evaporation at 400 under a high vacuum. The resulting product is dissolved in 200 ml of water, and 1 g of sodium bicarbonate and 50 ml of 20 sodium chloride solution are added and the mixture is extracted three times with 100 ml of ethyl acetate each time. The organic phases are dried over sodium sulphate. Filtration and concentration by evaporation yield 1.8 g of educt 8. The aqueous phase is acidified with approximately 20 ml of IN sulphuric acid and extracted five times with 120 ml of ethyl acetate each time. Drying over sodium sulphate, concentration by evaporation and chromatography of the residue according to i,a) yield 0.8 g of acid 9.

j) (2R)-2-amino-4-methyl-7-phosphono-3-heptenoic acid A solution of 3.3 g of acid 9 according to i) and 2.6 g of N,0-bis-trio methylsilylacetamide is stirred at room temperature for on~ hour under 0 ,8 argon. After the addition of 4.4 g of trimethylbromosilane, the mixture is stirred for 24 hours. The reaction mixture is added dropwise at 0° to X 400 ml of water, and the whole is stirred for 30 minutes. The organic phase is separated off and washed three times with 50 ml of water each time. The aqueous phases are extracted three times with 30 ml of dichloromethane each time and concentrated to 10 ml at 40° under a high vacuum. Chromatography on 20 ml of Dowex® 50 Wx8 using water as eluant, and lyophilisation of the eluate yield 0.4 g of 10 in the form of an amorphous white powder having a melting point of 252° (decomposition); [a]D -86.59 H0O); CH1i6NOsP.1 H20; calculated: C 37.05 6.9 N 5.5 found: C 36.3 H 6.5 N 5.6 In order to analyse the purity of the enantiomtr, a sample is derivatised to the amide with (R)-(+)-methoxytrifluoromethylpylphenylacetic acid chloride. 1H-NMR analysis (300 MHz) by integration of the 0CH3 signals Igives 2 94 (2R)-isomer (3.24 ppm) and 6 (2S)-isomer (3.17 ppm).

45 Example 8: (2R)-2-amino-7-phosphono-3-heptenoic acid a) (4R)-2,2-dimethyl-4-(1 '-hydroxyprop--2'-enyl)-oxazol-idine--3-carboxylic acid tert.-butyl ester (1) ml of a 2.4M solution of vinylmagnesium bromide in tetrahydrofuran are added at 0-5' wi~thin a period of 30 minutes to a solution of 25 g of (4S)-2,2-dimethyl-4-formyloxazolidine-3-carboxylic acid tert.-butyl ester (according to Example Sc) in 300 ml of dry tetrahydrofuran. The mixture is stirred at 0' for one hour, allowed to warm up to room temperature and then stirred at room temperature for a further one hour. 300 ml of buffer solution (1 molar, phosphate, pH 7) are added while cooling to 100. After minutes, the mixture is filtered, extracted twice with 150 ml of ethyl acetate each time and washed twice with 100 ml of water each time. The aqueous phase is extracted twice with 100 ml of ethyl acetate each time.

The organic extracts are dried over sodium sulpha:e aind concentrated by evaporation. Chromatography of the residue on silica gel using hexane/ ethyl acetate 4:1 yields 24.2 g of epimer mixture 1; C 1 3

H

2 3 NOti; calculated: C 60.68 H 9.01 N 5.44 found: C 60.7 H 9.1 N 5,6 b) (4R) -4-(41-e thoxycarbonylbuteny1) 2dime thy loxago 1-dile- 3 carboxylic acid tert.-butyl ester (2) A solution of 22.5 g of alcohol I according to a) and 0.3 ml of propionic acid in 38.5 ml of orthoformic acid ttiethyl ester is heated at 135-1400C for 4 hours, with ethanol slowly being distilled off. The mixture is concentrated by evaporation at 500 under a high vacuum and chromatographed on 300 g of silica gel. Elution with hexane/ethyl acetate 4:1 yields 23.9 g of 2, D 10.06 CH013); C171129"19; calculated: C 62.36 HI 8.93 N 4.28 found: C 62.2 11 8.9 N 4.4 c) (4R)-2,2-dimet yl-4-(5'-hydroxypentenyl)-oxazolidile-3-carboxylic acid tert.-butyl ester (3) 2. 7 g of lithium aluminium hydride are added in portions at 0-2' to a solution of 23.5 g of 2 according to b) in 550 ml of ab~solute diethyl ether. After stirring at 0-2' for 3 hours, a solution of 25 g of potassium hydrogen sulphate in 250 ml of water is added dropwise with 46 o Be

B

4* B *0 BO 4~ 00 B 0B B

B

44 ft 4~ C B BC

B,

o 0 I 9* 4B ft 44 cooling. The mixture is filtered through CeliteO and washed thoroughly with diethyl ether. The organic phase is washed twice with 200 ml of 1N hydrochloric acid each time and twice with 250 ml of 10 sodium bicarbonate solution each time. The aqueous phases are extracted twice with 100 ml of ether each time. The organic phases are washed with sodium chloride solution, dried over sodium sulphate and concentrated by evaporation. Chromatography on silica gel using hexane/ethyl acetate as eluant yields 18.6 g of 3, [a4] D -10-1o CHCl 3 ClSH2 7 N%1; calculated: 63.13 H 9.54 N 4.91, found: C 63.0 H 9.5 N 5.0 d) (4R)-4-(5'-bromopentenyl)-2,2-dimethyloxazolidine-3-carboxylic acid tert.-butyl ester (4) 7 ml of pyridine are added dropwise at 00 to a solution of 18.5 g of alcohol 3 according to 28.2 g of tetrabromomethane and 22.3 g of triphenylphosphine in 600 ml of dichloromethane. The mixture is stirred at 0-2* for 12 hours, concentrated by evaporation, taken up in 150 ml of ethyl acetate, filtered, concentrated to 50 ml and chromatographed on 200 g of silica gel. Elution with hexcape/ethyl acetate 10:1 yields 19.9 g of bromide 4, MaD -18.9' (cal, CHCl 3 Ci 5 H26110 3 Br; calculated: C 51.73 H 7.53 4.02 7o, Br 22.94 found: C 51.7 H 7.7 N 4.2 Br 23.0 e) (4R)-2,2-dimeth, 1- 4- i.-2-propy lpho sph onopeaitenyl) -oxazoal11dine- 3carboxyllic acid tert.-butyl ester() A solution of 19.9 g of bromide 4 according to d) in 60 ml of triisopropyl phosphite is heated at 130-135* for 20 hours at 100 mbar. The, excess reagent is distilled off at 600/0.1 mubar, and the residue is chromatographed on 250 g of silica gel. Elution with hexane/ethyl acetate 1:1 yields 20.6 g of phosphonic acid ester. [q D 8.6' (C-0.8, Old1 3

C

21 H~oNO 6 P; calculated: C 58.18 1, 9.30 3.23 P 7.15 found: C 57.4 H 9.3 N 3.2 79, P 7.5

B

ft It

II

to 0

J

47 f) N-((2R)-l-hydroxy-7-(diisopropylphosphonohept-3-en-2-yl)-carbamic acid tert.-butyl ester (6) A solution of 20.6 g of 5 according to e) in 800 ml of methanol is stirred at room temperature for 20 hours with 30 g of Amberlyst® 15 (H+ form). The mixture is filtered, washed with methanol, concentrated by evaporation and chromatographed on 100 g of silica gel. Elution with ethyl acetate yields 14.8 g of 6, [a] D -3.6 CHC13);

C

18

H

36

N

6 P; calculated: C 54.95 H 9,22 N 3.56 P 7.87 found: C 53.6 H 9.0 N 3.4 P 9.0 g) (2R)-2-tert.-butoxycarbonylamino-7-diisopropylphosphono- 3-heptenoic acid (7) To a solution of 7.4 g of alcohol 6 according to f) in 300 ml of acetone there are added dropwise at 0-2°C, within a period of 20 minutes, 15 ml of a solution which is 3.25 molar in chromium trioxide and 5.29 molar in sulphuric acid. The mixture is stirred at 0-2° for 2 hours and at room temperature for 4 hours, and then 30 ml of isopropanol, 300 ml of ethyl acetate and 200 ml of 20 sodium chloride solution are added. The aqueous phase 'j extracted three times with 250 ml of ethyl acetate each time, and the organic phases are dried over sodium sulphate and concentrated by evaporation. Chromatography on 200 g of silica gel using hexane/ethyl acetate/acetic acid 16:10:1 yields 4.55 g of acid 7, -24.90 CHC13).

h) (2R)-2-amino-7-phosphono-3-heptenoic acid (8) A solution of 3.1 g of acid 7 and 3 ml of N,O-bis-trimethylsilylacetamide in 200 ml of dry dichloromethane is stirred at room temperature for one hour. 3.5 ml of trimethylbromosilane are added, and the mixture is stirred at room temperature for 30 hours. The volatile portions are evaporated off, the residue is taken up in 50 ml of dichloromethane, and 250 ml of water are added at 0-20. The aqieous phase is separated of. and concentrated to 10 ml under a high vacuum. Chromatography on 20 ml of DowexI® 50 Wx8 using water as eluant, and lyophilisation of the eluate tlL-- -48yield 1.04 g of 8 in the form of an amorphous powder, [a'D -65.2' (cl,, 1 3 C-NMR (75 MHz, D 2 172.8 (CO 2 140.3 122.2 56.4 33.3 J=17, 27.3 J-134, 22.6 J=4, In order to analyse the purity of the enantiomer, a sample is derivatised to the amide trimethyl ester with (R)-(+)-nethoxytrifluorometbyiphenylacetic acid chloritde followed by diazomethane. IH-NMR analysis (300 MHz) by integration of the OCH 3 signals gives (2R)-isorner (3.54 ppm) and 5 (2S)-isomer (3.37 ppm).

Example 9: (2R)-2-amino-4-methyl-5-phosphono '3-pentenoic acid ethyl ester a) (2R,3S)-2-formylamino-3-hydroxy-4-methyl-4-pentenoic acid ethyl ester (1) aa) Starting from 1,1,3, 3-tetramethyl-1 3-disilane-2-azolidine-N-acetic acid ethyl ester 7.6 ml of a 1.6 molar solution of butyllithium in heXane are added at to a solution of 2.26 ml of N-cyclohexyl-N-isopropylamine in 60 ml of absolute tetrahydrofuran. After 20 minutes, the mixture is cooled to 0 -78' and there is added dropwise a solution of 3 g of 1,1,3,,')-tetramethyl-1,3-disila-2-azolidine-N-acetic acid ethyl ester in 60 ml of tetrahydrofuran. The mixture is stirred at -78* for one hour, and then 142 ml of an approx~riately 0.035 molar solution of cyclopentadienyl-bis- 0-1,2:5,6-diisopropylidene-D-.glucofuranosyltitanium(IV) chloride in ether are added and the mixture is stirred at -78' for 17 hours. The reaction solution is transferred via a small steel tube, by argon pressure, into a vessel containing a solution, cooled to -780, of 1.1 ml of methacrolein in 15 ml of tetrahydrofuran. The whole is allowed to warm up slowly to room temperature, and is then stirred for 2 hours. 1.5 ml of wacer are added, and the mixture is filtered. The filtrate is diluted with 250 ml of diethyl ether, and is then washed three times with 250 ml of approximately 10 sodium chloride solution each time and with 250 ml of saturated sodium chloride solution. The aqueous phases are extracted twice with 250 ml of diethyl ether each time. The organic phases are dried over sodium sulphate, concentrated by evaporation, and dissolved hot in 150 ml of cyclohexane. On cooling, 1,2:5,6-di-0-isoptopylidene-D- -49glucofuranos crystallises. The mother liquor is concentrated by evaporation, the re~kidue is taken up in 120 ml of tetrahydrofuran, 24 ml of water and 4.5 ni of acetic acid, and the mixture is stirred at room temperature for 2 hours. Concentration by evaporation at room temperature under a high vacuvw yields 10.6 g of residue, contamining (2R,3S)-2amino-3-hydroxy-4--methyl-4-pentenoic acid ethyl ester. A sample (5 mg) is derivatised for 2 'hours with 0.2 ml of trifluoroacetic acid anhydride in 0.3 ml of dichloromethane. Capillary gas chromatography (Chirasil'8'-L-Val, 90-180'/2' per minute) yields 99.25 (2R,3S)-enantiomer (retention time T rt'10.28 minutes) and 0.75 (2S,R).-enantionier (retention time 4: T =11.48 minutes). The main mixture is then heated under reflux for ret 51 hours in 80 ml of~ formic acid ethyl ester. Concentration by evapora- Stion and chromatograply on silica gel using hexane/ethyl acetate 1:1 yield 1.64 g of fotmamide 1. Analysis of a sample (5 mg) in the form of the acetate by gas chromatography (ChirasiVI-L-Val, 160-180', 1' per at minute): 99.2 (2R,3S)-enantiomer (T ret 13.64 minutes), 0.8 (2S,3R)-enantiomer (T rt 13,94 minutes).

a,b) Starting from isocyanoacetic acid ethyl ester 1.65 g of (S)-N-methyl-N-[2-(dimetbylamino)-ethylI-1-K(R)-1l ,2-bis-(diphenylphosphino)-ferrocenyl)-ethylamine and 1.105 g of bis(cyclohexylisocyanide)gold(l) tetrafluoroborate are added at 500 to a solution of 24.88 g of isocyanoacetic, acid ethyl ester and 18.51 g of methacrolein in 0 Ai 220 ml of 1,2-dichloromethane. The mixture to stirred at 50' for 5 hours under argon, concentrated by evaporation, tak~en up in 400 ml of diethyl ether and filtered, and the filtrate is concentrated by evaporation.

Distillation of the residue under a high vacuum (0.04 mbar) yields 33.62 g of a stereoisomeric mixture of 5-(2-propenyl)-oxazoline-4carboxylic acid ethyl ester having a boiling point of 42-520; MS.! m/e tv 183 (2 H 110 (80 85 (100 A solu ion of 33 g of this mixture in 74 ml of water and 33 ml of tetrahydrofutan is heated under reflux for 3 hours. Concentration by kivaporation in vacua yields 36.1 g of a mixture of stereoisomeric 2-formamino-3-hydroxy-4-methyl-4-pentenoic acid ethyl ester A sample (35 mg) Is derivatised in 2 ml of dichloromethane with 0.05 ml of N,0-bia-trimethylsilvlacatamide and analysed by means of capillary gas chromat~ogivaphy (ChiraiP-L-Val, 1500): 89.1 (2R,3S)-isomer (T ret 22.1 minutes), 5.8 %(2S,3R)-isomur (T re 23.1 minutes), 2.8 (2R,3R)-.isomer (T rt 24.3 minutes), 2.3 (2S,3S)isomer (T re 25.4 minutes) A soltution of 11 .42 ml of acetic anhydride in 50 ml of dichiorornethane is added dropwise at 0-3' within a period of 25 minutes to a solution, of 20.2 g of 2, 16.83 ml. of triethylamine and 0.62 g of 4 (dime thylamino) pyridine in 300 ml of dichloromethnne. After 30 minutes, the mixture is washed twice with ice-cold 2N hydrochloric acid and twice with 10 sodium chloride solution, The aqueous phases are extracted with 100 ml of dichioromethane, The organic phases are dried over sodium sulphate and concentrated by evaporation, and the residue is dissolved hot in hexane/ ethyl. acetate 4:1. on cooling slowly to approximately 30 there crystallise 1.82 g of racenic. (2*2*--onaio--ctx--ohl pentenoic acid ethyl ester having a melting point of 98-106'. The mother liqour is slowly cooled to -12'C Anct kept at that temperature for one hour. Filtration yields 15.04 g of acetate 3, mp. 73-759, 1000D -75.60 CfHGl 3 analysis by gas chromtogrpy(hrsl-LVl 6-8, V~ per minute): (2R,3S)-isomer 9.A.5 145mnts,(S$) isomer 2.2 (Tre 14.8 minutes), (2R.,3R-ipomer 242 (Tre 16.8 minutes), (2S,3s)-isomer 2.1 (T m 17ol minutes).

4 ret 44 ftV 20.64 g of anhydrous potassium carbonate are added At -16' to a solution of 2 R,3S)-2-formylamino-3-acetoxy-4-methyl-4-pentenoic acid ethyl ester in 400 ml of absolute ethanol, After stirring at -l80 to -11 0 Cfo 4 hours, 500 ml of buffer solution (1 molar, phosphate, pHi=7) Aa Added dropwise. The mixture is stirred at room temperature for 30 minites and extracted three times with 350 ml of dichloromethane each time. The organic phases are dried over sodium sulphate aiod ,Ioncentrated by evaporation) and the residue is chromatographed on 1 kg of sillica gel using hexane/othyl acetate 1:2 as oluant, yielding 9.8 g of alcohol 11.

51 b) (2R)-2-formylamino-4-methyl-5-diisopropylphosphono-3-pentenoic acid ethyl ester (A) To a solution of 14.19 g of 1 according to a) in 210 ml of 1,2-dichloroethane there are added at 18-20' 6.57 ml of thionyl bromide and, after stirring for 2 hours, 135 mi of water. After 15 minutes, the organic phase is separated off and washed three times with 150 ml of ice-water each time and once with 100 ml of ice-cooled saturated sodium hydrogen carbonate solution. The organic phase is dried over sodium sulphate and concentrated by evaporation, and the residue is dissolved in 60 mt of triisopropyl phosphite and stirred at 7 5 1 0 0 mbar for 17 hours. The excess reagent is distilled off at 90' under a high vacuum, Chromatography of the residue on 650 g of silica gel using ethyl acetate/methanol 20:1 yields 10.88 g of phosphonic acid ester 4, (t 0 -123. 5 (cml, CtC 'H-NMR analysis (300 NH) with the addition of (1R)-l-(9'-anthracenyl)-2,2,2-trifluoroethanol shows an enantiomeric purity of a 90 c) (2R)-2-amino-4-methyl-5-phosphono-3-pentenoic acid ethyl ester 23 mi of trimothylbromosilane are added dropwise at room temperature S within a period of 15 minutes to a solution of 10,3 g of 4 according to t I b) in 42 mi of dichloromethan, After 214 hours, 42 ml of othanol are a" dded while cooling with ice, and the mixture is stirred for 20 hours, The whole is then concentrated by evaporation and the residue is disdolvea three times in 70 mt of toluene each time and in each case is S concentrated by evaporation again, The residue is dissolved in 42 mi of ethanol, and 42 ml of propylene oxide are added. After 1 hours, the mixture is filtered. Drying the filtration residue in a vacuum desiccator over P0oslKOH (3 houra/800) yielde 6.17 g of 5 D -780 0) m.p, 194-197' (decomp., CGoIHNOsP; calculated: C 40,51 It 6.80 N 5.91 P 13.06 found: C 39.4 H 7.09 N 5.73 P 12.98 In order to analyse the purity of the enantiomer, a sample is derivatised to the amide dimethyl phosphonate with -(+)-methoytriflutoromethylphenylanetic acid chloride and diazomethano and analysed by '1-NM, (300 NH) using the integration of the 0013 signals: (R)-isomer k 93 (3.51 ppm), (2S)-Isomer 7 (3.37 ppm).

52 Example 10: (2R)"2-amino-4-methyl-5-phosphono-3-pentenoic acid A solution of 100 mg of (2R)-2-amino-4-methyl-5-phosphono-3-pentenoic acid ethyl ester according to Example 6 in 3 ml of IN hydrochloric acid is heated in a bath at 10000C for 4} hours. The solution is concentrated by evaporation and the residue is dried at 600 under a high vacuum for minutes. The residue is dissolved in 15 ml of ethanol, and 4 ml of propylene oxide are added thereto, Filtration and drying of the filtration residue in a vacuum desiccator over P0 5 s/KOH yield 62 mg of acid., In order to determine the purity of the enantiomer, a sample is derivatised to the amide with (R)-(+)-methoxytrifluoromethylphenyl acetic acid chloride and is analysed by 1H-NMR (300 MHz), integration of the OCHj signals: 95 (2R)-enantiomer (3.25 ppm) and 5 (2S)-enantiomer (3.18 ppm).

Example 11: E-2-amino-4-mothyl-5-ophosphno-3-pentenoic acid 12 g of E-2-amio-4-methyl-5-phphohono-3-pentenoic acid ethyl ester are stirred under reflux in 70 ml of water for 19 hours. The reaction mixture is slowly cooled to room temperature, stirred in an ice bath for one hour, filtered and washed with cold water, In this manner there is obtained E-2-amino-4-methyl-5-phosphono-3-pentenoie acid in the form of the monohydrate, m.p. 163" (decomp.).

Example 12: E-2-dimethylamino-4-methyl-5-phosphono-3-pentenoic acid A mixture of 3.56 g of E-2-amino-4-inethyl-5-phosphono-3-pentenoic acid ethyl ester, 45 ml of 98 formic acid and 30 ml of 37 aqueous formaldehyde solution is stirred at a bath temperature of 105' for minutes, The mixture is then concentrated to dryness by evaporation in vacuo. The residue is taken up in a little water and the whole is again concentrated by evaporation in vacuo. This procedure is repeated twice more. The solid residue is stirred with 80 ml of water. After one hour, the undissolved material in separated off over a hard filter and washed with water. The filtrate and the washing water are concentrated to dryness by evaporation in vacuo. The residue is suspended in 100 ml of water and, after the addition of 30 ml of IN sodium hydroxide solution, ii L- 1 -53 is left to stand at room temperature for 2 days. The reaction mixture is concentrated to a residual-volume of approximately 25 ml by evaporation in vacuo and purified by ion exchanger chromatography (Dowex W x 8-H20). The fractions which contain the desired product are combined, concentrated by evaporation in vacuo and recrystallised from water/ ethanol. In this manner there is obtained E-2-dimethylamino-4methyl-5-phosphono-3-pt-tenoic acid, m.p. 239' (decomp.).

Example 13: E-2-dimethylamino-4-mrthyl-5-phosphono-3-pentenoic acid ethyl ester ml of 8N ethanolic hydrogen chloride solution are added to 1.19 g of E-2-dimethylamino-4-methyl-5-posphono-3- pentenoic acid, and the mixture is stirred at 40' for 24 hours, The reaction mixture is concentrated to dryness by evapor~ation in, vacuo. After the addition of 30 ml of pure ethanol$ the mixture is again concentrated by evaporation, giving 1.90 g of reddish oil, which is dissolved in hot irvoprop~anol. After cooling there is obtained crystailline E-2-dimethylaniino-4-methyl-5-phospbone-3pentenoic acid ethyl ester hydrochloride, m.pw 20. decomp.).

Example,14: E-2-beniylamino-4-mthyl-5-phosphbno-3-pentenoic acid ethyl ester 16 mil of glacial acetic acid, 5.90 g of sodium acetate (anhydrous) and 12.2 ml of benzaldeb),1e are added to a solution of 5.6F' g of E-2-amino- 4-methyl-5-pihosphono-3" pentenoic acid ethyl ester in 4t8 ml of water and 48 nil of ethanob, 15.70 g of sodium borohydricie are added in approximately 70 portions within a period of one hour with intensive cooling I with ice 'sodiim chloride, 4 ml of benzaldehyde b,,ing added after half the addition has taken place, after approximately 30 minutes. The temporature of the reaction mixture is kept at from 0 to 10'. When the addition is complete, the mixture is stirred at 0' for one hour to complete the reaction, and then IN hydrorbhloric acid is added dropwise until an acidic reaction to Congo rsd takes place. The undissolved salts 4a f-iV.--rod Qff and washed with water. The filtrate is concentrated. to dryness 'by evapotptin in vatuo, and the residue concentrated by evaporation twice 54 more after the addition of ethanol. The residue is then stirred with 150 ml of ethanol, and the'undissolved material is filtered off with suction and washed with ethanol. 25 ml of propylene oxide are added to the filtrate, and the mixture is then stirred for 4 nours. The material which crystallises out (mainly educt) is filtered off. The mother liquor is concentrated to dryness by evaporation and stirred with 350 ml of ethyl acetate. The crystalline crude product obtained after filtration with suction is recrystallised from ethanol. In this manner there is obtained E-2-benzylamino-4-methyl-5-phosphono-3-pentenoic acid ethyl ester, m.p. 192' (decomp.).

4 Example 15: E-2-benzylamino-4-methyl-5-phosphono-3-pentenoic acid ethyl ester S"4, A solution of 1.00 g of E-2-benzylamino-4-methyl-5-phosphono-3-pentenoic acid ethyl ester in 6 ml of water is stirred under reflux for 20 hours.

The reaction mixture is concentrated to dryness by evaporation in vaco.

Ethanol is added to the residue, and the mixture is again concentvated by i, r evaporation. This process is repeated twice more. The residue is dissolved in boiling methanol. After cooling there is obtained crystalline E-2-benzylamino-4-methyl-5-phosphono-3-pentenoic acid, s" m.p. 150' (decomp.).

Example 16: E-2-isopropylamino-4-methyl-5-phosphono-3-pentenoid acid ethyl ester 6.64 g of sodium acetate (anhydrous) and 18 ml of acetone are added to a solution of 6.40 g of E-2-amrino-4-methyl-5-phosphono-3-penteooic acid ethyl ester in 54 ml of water and 18 ml of glacial acetic acid. 17.67 g of sodium borohydride are added in approximately 70 pn- 'on within a period of 90 minutes with intensive cooling with ice/tdiu chloride, 18 ml of acetone being added after 20 minutes and aftet 'C minutes. When the addition is complete, the thick white suspension is stirred at 0* for minutes to complete the reaction, and then 1N hydrochloric acid is added dropwise until an acidic reaction to Congo red takes place. The resulting clear solution is concentrated by evaporation in vacuo, and the residue is concentrated by evaporation twice more after the addition of ethanol. The residue is then stirred with 200 ml of ethanol at room 55 temperature, and the undissolved material is filtered off and washed with ethanol. The filtrate is concentrated by evaporation in vacuo, and the residue is recrystallised from isopropanol. In this manner there is obtained E-2-isopropylamino-4-methyl-5-phosphono-3-pentenoic acid ethyl ester hydrochloride, m.p. 203-2050 (decomp.).

Example 17: E-2-isopropylamino-4-methyl-5-phosphono-3-pentenoic acid A solution of 1.20 g of E-2-isopropylamino-4-methyl-5-phosphono-3pentenoic acid ethyl ester hydrochloride in 7 ml of water is stirred under reflux for 20 hours. The reaction mixture is concentrated to dryness by evaporation in vacuo. Ethanol is added to the residue, and the mixture is again concentrated by evaporation. This process is repeated twice more. The residue is dissolved in 25 ml of ethanol, a total of 5 ml of propylene oxide is added dropwise thereto with stirring, and the whole is concentrated to dryness by evaporation. The residue is dissolved in a little water, and ethanol is added until the solution becomes cloudy. The solution is stirred at room temperature for 4 hours to complete the reaction, during which time crystallisation slowly takes place. The product is filtered off, washed with ethanol and diethyl ether and dried at 1000 under a high vacuum. In this manner there is obtained E-2-iso- S propylamino-4-methyl-5-phosphono-3-pentenoic acid, m.p. 225-227' (decomp.).

Example 18; E-2-methylamino-4-methyl-5-phosphono-3-pentenoic acid a) 2-(N-methyl-N-formylamino)-3-hydroxy-4-methyl-4-pentenoic acid ethyl ester (1) 60 g of 5-(2-propenyl)-2-oxazoline-4-carboxylic acid ethyl ester, prepared according to FPample 1, are dissolved in 200 ml of dry dichloromethane under argon. A suspension of 16.60 g of trimethyloxonium tetrafluoroborate in 200 ml of dry dichloromethane is then added dropwise at The reaction mixture is stirred at room temperature for 17 hours, and then 150 ml of water and 45 ml of saturated potassium bicarbonate solution are added slowly, so that a pH of 7 is produced. The organic phase is separated off and washed twice With water and once with saturated sodium chloride solution, and is then dried over sodium I, i i 1 56 sulphate. After the dichloromethane has been distilled off, the oily residue is distilled in a bulb tube, b.p. 120-1300/13 Pa. In this manner there is obtained 2-(N-methylformylamino)-3-hydroxy-4-methyl-4-pentenoic acid ethyl ester in the form of a light-yellow honey, IR (CH 2 C12): 3550 17'0 (CO ester); 1675 (CO amide).

b) E-2-(N-methyl ',T-fortylamino)-4-methyl-5-diisopropyl-phosphono-3pentenoic acid ethyl ester (2) 7.70 ml of thionyl bromide are added dropwise at 200 under argon to a solution of 17.80 g of 2-(N-methylformylamino)-3-hydroxy-4-methyl-4pentenoic acid ethyl ester in 248 ml of 1,2-dichloroethane. The mixture 0 *:1 "6 a is stirred at room temperature for 2 hours. 150 ml of water are then S added dropwise with slight cooling The two-phase mix' 're is stirred thoroughly for a further 20 minutes to complete the reaction. The organic phase is separated off and washed three times with water/ice, once with ice/saturated potassium bicarbonate solution and once with saturated sodium chloride solution. To the intermediate obtained after drying over sodium sulphate and removal of the 1,2-dichloroethane by a CC o distillation at 350 in vacuo there are added at room temperature 66 ml of triisoprcpyl phosphite, and the mixture is then stirred at 750 under reduced praaure (approximately 13 kPa) for 17 hours. The excess triisopropyl phosphite and other volatile by-products are then distilled off under a high vacuum. Purification by column chromatography (silica gel, ethyl acetate) yields E-2-(N-methylformylamino)-4-methyl-5-diisopropylt phosphono-3-pentenoic acid ethyl ester in the form of a yellowish honey; IR (CH 2 Cl 2 1740 (CO ester); 1670 (CO amide); 1235 980-1010 According to the 'H-NMR spectrum, the compound is in the form of a mixture of two rotamers.

S* c) E-2-methylamino-4-methyl-5-phosphono-3-pentenoic acid (3) ml of trimethylbromosilane are added dropwise at 20' within a period of 10 minutes under argon to a solution of 9.50 g of E-2-(N-methylformylamino)-4-methyl-5-diisopropylphosphono-3-pentenoic acid ethyl ester in '0 ml of dry dichloromethane. After stirring at room temperature for 57 *4 It

'I

I. I

I

It 11 I t I I Il It I I I rI t I II -hours, 37 ml of ethanol are added dropwise within a period, of minutes, and the whole is stirred for a further 20 hours. The clear reaction solution is then concentrated to dryness by evaporation in vacuo. The residue is concentrated by evaporation twice more in each case after the addition of 30 ml of toluene. 128 ml of 2N hydrochloric acid are added to the resulting oil, and the mixture is stirred at a bath temperature of 850 for 16 hours. The reaction mixture is concentrated by evaporation in vacuo. Concentration by evaporation twice after the addition of ethanol/toluene 1:1 yields an oily residue, which is dissolved in 51 ml of ethanol and to which there is added dropwise a solution of 51 ml of propylene oxide in 51 ml of ethanol.. The product obtained in crystalline form is filtered off after 2 hours and recrystallised from water/ethanol. En this manner there is obtained E-2methylamino-4-methyl-5-phosphono-3-pentenoic acid, m.p. 2390 (decomp.).

Example 19: The following can also be prepared in a manner analogous to that described in Examples 1-3 or 6 and 9: E-2-amino-5-phosphino-3-pentenoic acid ethyl ester, m.p. 172-173'; E-2-amino--5-phosphino-3-pentenoic acid butyl ester, m.p. 160-161'; E-2-amino-5-phosphono-3--pentenoic acid ethyl ester, m.p. 167-168'; E--2-amino-5-phosphono-3-pentenoic acid butyl ester, m.p. 160-16l0; E-2-amino-5-phosphono-3-pentenoic acid octyl ester, m.p. 161-162'; E-2-mino-5-phosphono-3-pentenoic acid propyl ester, m.p. 161-162'; E-2-amino-5--phosphono-3-pentenoic acid pentyl ester, m.p. 160-161*; E-2-amino-5-phosphono-3-pentenoic acid isobutyl ester, m.p. 163-164'; E-2-amino-5--phosphono-3-pentenoic acid sec.-butyl ester, m.p. 169-170'; E-2-amino-4-methyl-,5-phosphono-3-pentenioic acid methyl ester, m.p. 193-l94*, [water/acetone (9:1)1; E-2-amino-4-methyl-5-phosphono-3-pentenoic acid n-propyl ester, m.p. 184.4850, (water); E-2-.amino-4-methyl-5-phosphono-3-pentenoic acid n-butyl Oster, m.p. 186-187*, [water/acetone (2:1)1; E-2-amino-4-methyl-5-phosphono-3-pentenoic acid isobutyl ester, m.p.

181-182*, [water/acetone (9:1)1; A, 'I -ff 58 E-2-amino-4-methyl--5-phosphono-3-pentenoic acid n-pentyl ester, m.p. 207-208'; E2-amino-4-methyl-5-phosphono-3-.pentenoic acid n-hexyl ester, E-2-amino-7-phosphono-4-heptenoic acid butyl ester, m.p. 186'; E-2-amino-5-posphono-4--pentenoic acid methyl ester, m.p. 219 ~220';

E-

2 -amino-5-phosphono-4'-pentenoic acid ethyl ester, m.p. 2340;

E-

2 -amino-5-phosphono-4 -pentenoic acid butyl ester, in.p. 239';

E-

2 -amino-5-phosphono-4-pentenoic acid octyl ester, m.p. 2360;

E-

2 -amino-5-phosphono-4-pentenoic acid 2-hydroxyethylester, m.p. 197'.

Example 20, The following can also be prepared in a manner analogous to that described in E~xamples 4, 11, 12, 17 and 18 or 5, 7, 8, 9 and E-2-amino-5-phosphono-4-pentenoic acid, m.p. 21 9-220'; thy lpho sphonyl- 4-pentenoic acid, m.p. 222'; E-2-amino-5-butylphosphonyl-4-pentenoic acid, m.p. 232-2331; E-2-amino-5-octylphosphonyl-4-pentenoic acid, m.p. 221-223'; E-2-amino-5-dodecylphosphonyl-4-pentenoic acid, m.p. 2110; E-2-amino-6-phosphono-4-hexenoic acid, m.p. 244-246'; E-2-amino-6-methy,*phosphony1-4-hexenoic acid, m. p. 145-1 E- 2-amino- 6-buty lpho sphonyl1-4-hexeno ic acid, m.p. 216'; E- 2-amino- 6-o cty),pho sphony1- 4-hexeno ic acid, m.p. 209-210*; E-2-amino-6-dodecylphosphonyl-4-hexenoic acid, m.p. 197-200'; E-2-amino'-7-phosphono-4-heptenoic acid, m.p. 1250 (decompusition); (2R)-E-2-anino-4-fluoro-5-phosphono-3-pentenoic acid, (a]ID a 48

H

2 1 3 C-NMR-spectrum (75 MHz, D 2 172.7 (COOH); 161.5 (dxd, J=263+12: 100.9 J=11: CO); 49.5 (C 2 33.5 (dxd, J=128+26: CO); E-2-amino-5-phosphono-3-pentenoic acid, white amorphous powder, 'H-NNR (DzO): 2.39 (dd, 211, 4.27 1H1, 5.53 (mn, 1H, 5.87 (mn, 1H, in.p. after recrystallisation from ethan, )l/water 1%~-1920; E-2-amino-4-methyl-5-phosphono-3-pentenoic acid, IH-NMR (D20): 1.73 (a, 3HJ, CHO); 4.55 111, -59- E-2 -amino- 5-me thylpho sphony--3-pentenoic acid, amorphous white powder, 'H-NMR (D, 2 .2.55 (dcl, 2H-, 4.38 111, 5.64 (in, 1H, 5.91 (in, 1H, E- 2-amino- 5-pho sphino- 3-penteno ic acid, m~p. 139-140'; E-2-amino-4-me.thyl-5-phosphino-3-pentenoic acid, m.p. 176-177'; (2S)-E--2-amino-4-met'hyl-5-phosphono-3-pentenoic acid, m.p. 196', [lo= +97.1 1.90 water);

D

(2R)-E-2-amino-4-methyl-5-phosphono-3-pentenoic acid, m.p. 194', [al'o= -96.7 1.20 water);

D

E-2-arnino-4-inethyl-5-methylphosphonyl-3-pentenoic acid, 'H-NMR (DaO): 1.20 3H, C1 3 1.75 3H1, CHO 3 2.45 2H1, A 4.50 1H, 5.15 (mn, 111, E -2-amino-2-methyl-5-phosphono-3-pentenoic acid, in.p. 225-226' (from water); E-2-ainino-3-methyl-5-.phosphono-3-pentenoic acid, white powder, in.p. 1680, 1H-NMR (Da0): 1,50 UH, 0113); 2.4 (in, 2H1, CH2); 4.30 1H1, 0(2-H); 5.60 (in, 11, E-2 -amino- 5-me thyI- 5-pho sphono- 3-pent eno ic acid, white amorphous solid, 'H-NU~R (D 2 1.05 (dd, 3H, OH 3 2.45 (mn, 111, 0(5)-Hf);d 4.33 2H1, 5.5 and 5.9 (2m, 2H1, 0(3)-H and E-2-ainino-4-ethyl-5-phosphono-3-pentenoic acid, in.p. 1760; E--mn--rpA,5popoo3pneni cd ~.13 E-2-amino-4-propyl-5-phosphono-3-pentenoic acid, m.p. 18638; E-2-amino-4-butryl-5-phosphono-3-pentenoic acid, m.p. 2061'7; E- 2-amino- 4- ter t. -bu tyI- 5-pho sphono- 3-pen tLno ic acid, in.p. 252-253', IH-NMR 0D 2 0.95 9H, (C033); Z-2-aipino-4-tert.-butyl-5-phosphono-3-pentenoic acid, 'H-NMR 1.08 9H1, (013)3); 2.45 (in, 2H1, 0112); 4.95 111, 5.20 (mn, 1H, E-2-amino-4-benzyl-5-phosphono-3-pentenoic acid, colourless needles, m.p. 196-198'; E-2-amino-4-phenyl-5-phosphono-3-pentenoic acid, colourless needles, in.p. 230-2330-0 E- 2-amino- 4-ne thy 1- 5-me thy lpho sphono- 3-penteno ic acid as by-product, n.p. 149-150'.

60 Example 2i: E-2-methylamino-4-methyl-3-pentenoic acid ethyl ester ml of 8N ethanolic hydrogen chloride solution are added to 1.20 g of E-2-methylamino-4-methyl-5-phosphono-3-pentenoic acid, and the mixture is stirred at 40° for 25 hours. The reaction mixture is concentrated to dryness by evaporation in vacuo. Concentration by .vaporation twice after the addition of ethano) /toluene 1:1 yields an oily residue, which is dissolved in 5 ml of ethanol and to which there is added dropwise a solution of 5 ml of propylene oxide in 5 ml of ethanol. The product obtained in crystalline form is filtered off after 2 hours and washed with ethanol and ether. After ijfing (800, 4 hours) under a high vacuum, there is obtained E-2-methylamino-4-methyl-5-phosphono-3-pentenoic acid ethyl ester, m.p. 235-240° (with decomposition).

Example 22: Preparation of 1000 capsules each containing 10 mg of the active ingredient of Example 6 and having the following composition: E-2-amino-6-phosphono-4-hexenoic acid 10.0 g lactose 207.0 g modified starch 80.0 g magnesium stearate 3.0 g Method: All the pulverulent constituents are sieved through a sieve having a mesh width of 0.6 mm. The active ingredient is then placed in a suitable mixer and mixed first with the magnesium stearate and then with the lactose and starch, until a homogeneous mixture is obtained. No. 2 gelatin capsules are each filled with 300 mg of this mixture, a capsulefilling machine being used.

Capsules that contain from 10 to 200 mg of one of the other disclosed compounds mentioned in Examples 1-20 are prepared in analogous manner.

Example 23: Preparatio- 10,000 tablets each containing 10 mg k" the active ingredient of Exslaple 6 and having the following composi:ion: E-2-amino-6-phosphono-4-hexenoic acid 100.00 g lactose 2535.00 g corn starch 125,00 g 61 polyethylene glycol 6000 150.00 g magnesium stearate 40.00 g purified water q.s.

Method: All the pulverulent constituents are sieved through a sieve having a mesh width of 0.6 mm. The active ingredient is then mixed in a suitable mixer with the lactose, the magnesium stearate and half of the starch. The other half of the starch is suspended in 65 ml of water, and the suspension is added to a boiling solution of the polyethylene glycol in 260 ml of water. The resulting paste is added to the powders and the mixture is granulated, if necessary with the addition of more water. The granulate is dried overnight at 350, forced through a sieve having a mesh width of 1.2 mm, and compressed to form tablets which have a breaking groove.

Tablets that contain from 10 to 200 mg of one of the other disclosed compounds mentioned in Examples 1-20 are prepared in analogous manner.

D

vA

I

Claims

1. A process for the manufacture of unsaturated amino acid compounds of formula a 4 S -R5 HO- -A- in which Ri is hydrogen, alkyl or hydroxy, Ra is hydrogen, alkyl, halo- t alkyl, hydroxyalkyl, lower alkoxyalkyl, aryl-lower alkyl, lower alkenyl, halogen or aryl, R 3 is hydrogen, alkyl or aryl, R4 is hydrogen or alkyl, t r R 5 is unsubstituted carboxy or esterified or amidated carboxy, R 6 is an amino group that is unsubstituted or substituted by alkyl or by arylated alkyl, A is unsubstituted or alkyl-substituted a,w-alkylene having from 1 Sto 3 carbon atoms (C-atoms) or is a direct bond, and B is methylene or a bond, with the proviso that A is unsubstituted or alkyl-substituted a,w-alkylene having from 1 to 3 C-atoms when B is a direct bond, and to S the salts thereof, characterised in that in a compound of formula I3 4 (II), in which Z i is free or protected hydroxy, Zz is an RI group or protected hydroxy, Z 5 is an Rs group or protected carboxy, Z6 is a protected group R 6 and RI, R2, R3, Ri, Rs, R6, A and B are as defined above, the pro- tected groups Z6 and, when applicable, Zi, Z 2 and/or Z 5 are freed by treatment with a tri-lower alkylhalosilane and, if desired, the resulting compound is converted into a different compound of formula I, a resulting mixture of optical isomers is resolved into the components and the desired isomer is separated off, and/or a resulting free compound is converted into a salt or a resulting salt is converted into the free compound or into a different salt. -1

63- 2. A process according to claim 1, characterised in that a compound of formula in which R2, R 3 R4~, A and B are as defined for formula I, Z5 has the meaning of R5 or is protected carboxy, Z6 is a protected group R 6 and X reactive esterified hydroxy, is reacted with a compound of formula 00 0,z i_1 (IV), 00 4 0 0 4 in which Z 1 is free or protected hydroxy, Z has th' meaning of R 1 or is protected hydroxy and R is an etherifyling group, in the resulting inter- mediate of formula 114 0, 00 0 000S the protected gopZ6and, when applicable, Z 1 Zz and/or Z 5 are freed by treatment with a tri-lower alkylhalosilane and, if desired, in a com- p ound obtainable according to the process in which R5 is esterified carboxy, the estenified carboxy group is converted into carboxy or, in a IA compound obtainable according to the process in which R 5 is carbo, y, the o carboxy group Is converted i~to an esterified carboxy group and/un, if desired, a resulting br t'Qtomula I is converted into a salt or a resulting salt Is converted in~to a different salt or into a free compound of formula I and/or, if desired, an optieal isomer is isolated from a mixture of stereoisomeric forms of a resulting compound of- formula I or of a salt thereof. 3. A process according to claim 1 for the manufacture of compounds of formula I in i'hich Ri, Rq~ R3, Rill A and 13 are as defined in claim 1 and Rs is esterified ov amidated carboxy, and salts thereof, character-, ised in that a comrfound of formula 64 3 j 1 B- Z (III) in which Ra, R 3 A and B are as defined for formula I, Zs has the meaning of R 5 Z6 is protected amino, and X is reactive esterified hydroxy, is reacted with a compound of formula R ZI-- (IV), 2 S in which Zi is free or protected hydroxy, Z 2 has the meaning of Ri or is 9 a 4 protected hydroxy and R is an etherifying group, in the resulting inter- mediate the protected groups Z 6 and, when applicable, Z 1 and/or Z2 are S freed, whilst R 5 is retained, by treatment with trimethylbromosilane and, if desired, a resulting compound of formula I is converted into a salt or S* 2 a resulting salt is converted into a different salt or into a free com- pound of formula I and/or, if desired, an optical isomer is isolated from a mixture of stereoisomeric forms of a resulting compound of forr'la I or of a salt thereof. #4 4 1t 4 14 4. A process according to claim 1 for the manufacture of compounds of Lt t« formula I in which R 2 R 3 Ri, R6, A and B are as defined in claim I and Rs is carboxy, and the salts thereof, characterised in that in a compound of formula II in which Z2 is free or protected hydroxy, Z2 is an RI group or protected hydroxy, Z5 is free or protected carboxy and Z 6 is protected group Rg and Ri, R 2 R4, R 6 A and B are as defined above, the protected groups Z 6 and, when applicable Zi, Z 2 and/or Zs are freed by treatment with a tri-lower alkylhalosilane and, if desired, in a com- pound obtainable according to the process in which Rs is esterifed carboxy, the esterified carboxy group is converted into carboxy or, in a compound obtainable according to the process in which Rs is carboxy, the carboxy group is converted into an esterified carboxy group and/or, if desired, a resulting compound of formula I is converted into a salt or a resulting salt is converted into a different salt or into a free compound 65 of formula I and/or, if desired, an optical isomer is isolated from a mixture of stereoisomeric forms of a resulting cumpound of formula I or of a salt thereof. A process according to any one of claims 1, 2 and 4, char cterised in that the starting material used is a compound of formulae II or IV in which protected hydroxy Zi and/or Z 2 is hydroxy etherified by an aliphatic alcohol, such as hydroxy etherified by a lower alkanol, lower alkenol or lower alkynol each of which is unsubsti.uted or substituted by halogen or, in a position higher than the a-position, by hydroxy, oxo, lower alkoxy, lower alkanoyloxy and/or by mono- or di-lower alkylamino. rii ft I' 6, A process according to claim 3, characterised in that the starting material used is a compound of formula IV in which protected hydroxy Z 1 and/or Z2 is hydroxy etherified by an aliphatic alcohol, such as hydroxy it etherified by a lower alkanol, lower alkenol or lower alkynol each of which is unsubstituted or substituted by halogen or, in a position higher b it than the a-position, by hydroxy, oxo, lower alkoxy, lower alkanoyloxy and/or by mono- or di-lower alkylamino. S 4 1 7. A process according to any one of claims 1, 2 and 4, characterised in that the starting material used is a compound of formulae II or IV in which protected hydroxy Z 1 and/or ZZ is lowor alkoxy. 8. A process according to claim 3, characterised in that the starting material used ia a compotu~J of formula IV in which protected hydroxy Z 1 and/or Za is lower alkoxy. 9. A process accordig to any one of claims 1 to 8, characterised in that the starting material used is a compound of formulae II or III in which the protected group Z 6 is an acylamino group, optionally N-substituted by lower alkyl or phenyl-lower alkyl, A process according to any one of claims 3, 6 and 8, characterised in that the starting material used is a compound of formula III in which the protected group Z 6 is an acylamino group. i -66 11. A process according to any one of claims 1 to 9, characterised in that the starting material used is a compound of formulae II or III in which the protected group Z 6 is the acyl group of a carbonic acid semi- ester. 12. A process according to any one of claims 1 to 9, chqracterised in that the starting material used is a compound of formulae II or III in which the protected group Z 6 is a lower alkoxycarbonylamino group that is unsubstituted or substituted in the 1- or 2-position, for example tert.- butoxycarbonylamino. 13. A process according to any one of claims 1 to 8, characterised in that the starting material used is a compound of formulae II or III in S which the protected group Z 6 is a lower alkanoylamino group, optionally St t S N-substituted by lower alkyl or phenyl-lower alkyl, for example formyl- Samino. 14. A process according to any one of claims 3, 6, 8 and 10, character- ised in that the starting material used is a compound of formula III in S which the protected group Z 6 is a lower alkanoylamino group, for example formylamino. A process according to any one of claims 1 to 14, characterised in that the tri-lower alkylhalosilane used is a tri-lower alkylchlorosilane, tri-lower alkylidosilane or tri-lower alkylbromosilane. 16. A process according to any one of claims 1 to 14, characterised in that the tri-lower alkylhalosilane used is a tri-lower alkylbromosilane. 17. A process according to any one of claims 1, 2, 4, 5, 7, 9, 11 to 13, N 15 and 16, characterised in that the tri-lower alkylhalosilane used is trimethylbromosilane. 18. A process according to any one of claims 3, 6, 10 and 14, charac- terised in that the tri-lower alkylhalosilane used is trimethylbromo- silane. 67 19. A process according to any one of claims 1, 2, 4, 5, 7, 9, 11-13 and to 17, rharacterised in that the protected groups Zi, Zz, Z 5 and/or Zg are freed in a halogenated hydrocarbon. A process according to any one of claims 3, 6, 8, 10, 14 and 18, characterised in that the protected groups Zi, Z 2 Z 5 and/or Z 6 are freed in a- halogenated hydrocarbon. 21. A process according to any one of claims 1 to 20, characterised in that the protected groups Z 1 Z 2 Z5 and/or Z 6 are freed in a halogenated aliphatic hydrocarbon. S 22. A process according to any one of claims 1, 2, 4, 5, 7, 9, 11-13, S 15 to 17 and 19, characterised in that the reaction is carried out in *4 dichloromethane as solvent or diluent, 00* 1 23. A process according to any one of claims 3, 6, 8, 10, 14, 18 and 4t characterised in that the reaction is carried out in dichloromethane as solvent or diluent. 24. A process according to any one of claims 1 to 23, characterised in that a substance absorbing hydrogen halide is added, .4 A process according to any one of claims 3, 6, 8, 10, 14, 18, and 23 characterised in that a substance absorbing hydrogen bromide iq added. 26. A process according to any one of claims 1 to 25, characterised iin that an epoxy-lower alkane in admixture with a lower alkanol is addef6 as substance absorbing hydrogen halide. 27. A process according to any one of claims 1, 2, 4, 5, 7, 9, 11-13, 15-17, 19, 21, 22 and 24, characterisec' in that propylene oxide in admixture with ethanol is added as subs-.ance absorbing hydrogen halide. I C~C~ 1 i 68 28. A process according to any one of claims 3, 6, 8, 10, 14, 18, 20, 23 and 25, characterised in that propylene oxide in admixture with ethanol is added as substance absorbing hydrogen bromide. 29. A process according to any on Df claims 1 to 28 for the manufacture of unsaturated amino acid compounds of formula -R HO---A-I in which R 1 is hydrogen, alkyl or hydroxy, RZ is hydrogen, alkyl, halo- 060* p alkyl, hydroxyalkyl, lower alkoxyalkyl, aryl-lower alkyl, lower alkenyl, halogen or aryl, R3 is hydrogen, alkyl or aryl, R4i is hydrogen or alkyl, ao R 5 is unsubstituted carboxy or esterified or amidated carboxy, R 6 is an amino group that is unsubstituted or substituted by alkyl or by arylated alkyl, A is unsubstituted or alkyl-substituted ,uw-alkylene having from 1 S to 3 carbon atoms (C-atoms) or is a direct bond, and B is methylene or a bond, with the proviso that A is unsubstituted or alkyl-substituted a,w-alkylene having from 1 to 3 C-atoms when B is a direct bond, in the form of those enantiomers in which the C-atom carrying the amino group R 6 ri is in the R-configuration, and the salts thereof, characterised in that the starting material used is a compound of formula IV or compounds of formulae II and III in which the C-atom carrying the Z6 group is in the R-configuration. A process for the manufacture of unsaturated amino acid compounds of formula HO- B CQf (Ia) in which Rt is hydrogep, alkyl or hydroxy, R 2 io hydrogen, alkyl, halo- alkyl, hydroxyalkyl, lower alkoxyalkyl, aryl-lower alkyl, lower alkenyl, halogen or aryl, R 3 is hydrogen, alkyl or aryl, Ri is hydrogen or alkyl, Rs is carboxy, R 6 is an amino group that is unsubstituted or substituted by alkyl or by arylated alkyl, A is unsubstituted or alkyl-substituted 69 a,-alkylene having from 1 to 3 carbon atoms (C-atoms) or is a direct bond, and B is methylene or a bond, with the proviso that A Is unsub- stituted or alkyl-substituted a,w-alkylene having from 1 to 3 C-atoms when B is a direct bond, and the salts thereof, characterised in that a compound of formula A_ R (Ib), HO- in which R is an esterified carboxy group, is hydrolysed in water without the addition of acid or base. 4 4 *M I 31. A process according to claim 30, characterised in that the starting i material used is a compound of formula Ib in which 1R is a lower alkoxy- carbonyl group. 4 32, A process according to any one of claims 1 to 31, characterised in that a compound of formula I in which Ri is hydrogen, alkyl having up to and including 12 carbon atoms, or hydroxy, R2 is hydrogen, lower alkyl, halo-lower alkyl, hydtoxy-lower alkyl, lower alkoxy-lower alkyl, phenyl- lower alkyl that is unsubstituted or substituted in the phenyl moiety, lower alkenyl, halogen, or unsubstituted or substituted phenyl, R 3 is hydrogen, lower alkyl or unsubstituted or substituted phonyl, R4 is hydrogen or lower alkyl, R 5 is free or pharmaceutically acceptable esterified or amidated carboxy, R6 is amino, or mono- or di-lewer alkylamino, A is unsubstituted or lower alkyl-substituted a,w-alkylene having from 1 to 3 carbon atoms or is a bond, and B is methylene or a bond, with the proviso that A is other than a bond when B is a bond, the substituents of phenyl being selected from the group consisting of lower alkyl, hydroxy, lower alkoxy, halogen, amino, halo-lower alkyl, hydroxy- lower alkyl, amino-lower alkyl and nitro, or a pharmaceutically acceptable salt thereof, is manufactured. 33. A process according to any one of claims 3, 6, 8, 10, 14, 18, 20, 23, and 28, characteried in that a compound of formula I in which RI is hydrogen, alkyl having up to, iad including 12 carbon atoms, or hydroxy, R 2 is hydrogen, lower alkyl, halo-lower alkyl, hydroxy-lower alkyl, lower r A 70 I** *9 9c a 44 4 at llt If I *119 9% r It I It a i It I I alkoxy-lower alkyl, phenyl-lower alkyl that is unsubstituted or substi- tuted in the phenyl moiety, lower alkenyl, halogen, or unsubstituted or substituted phenyl, R 3 is hydrogen, lower alkyl or unsubstituted or sub- stituted phenyl, R4 is hydrogen or lower alkyl, R; is pharmaceutically acceptable esterified or amidated carboxy, R6 is amino, or mono- or di- lower alkylamino, A is unsubstituted or lower alkyl-substituted a,w- alkylene having from 1 to 3 carbon atoms or is a bond, and B is methylene or a bond, with the proviso that A is other than a bond when B is a bond, the substituents of phenyl being selected from the group consisting of lower alkyl, hydroxy, lower alkoxy, halogen, amino, halo-lower alkyl, hydroxy-lower alkyl, amino-lower alkyl and nitro, or a pharmaceutically acceptable salt thereof, is manufactured. 34. A process according to claim 33, characterised in that a compound of formula I in which RI to R4, A and B are as defined in claim 33, R 5 is lower alkoxycarbonyl or lower alkoxycarbonyl substituted by amino, mono- or di-lower alkylamino, hydroxy or by lower alkanoyloxy and R 6 is amino or mono-lower alkylamino, or a pharmaceutically acceptable salt thereof, is manufactured. 35. A process according to any one of claims 1 to 31, characterised in that a compound of formula I in which RI is hydrogen, alkyl having up to and including 12 carbon atoms, or hydroxy, R 2 is hydrogen, lower alkyl, phenyl, halophenyl or phenyl-lower alkyl, R 3 and R4 are hydrogen or lower alkyl R5 is carboxy and R 6 is amino, A being unsubstituted or lower alkyl-substituted a,w-alkylene having from 1 to 3 carbon atoms or being a bond and B in each case being methylene or a bond, with the proviso that A is other than a bond when B is a bond, or a pharmaceutically accept- able salt thereof, is manufactured. 36. A process according to any one of claims 3, 6, 8, 10, 14, 18, 20, 23, and 28, characterised in that a compound of formula I in which RI is hydrogen, alkyl having up to and including 12 carbon atoms, or hydroxy, R2 is hydrogen, lower alkyl, phenyl, halophenyl or phenyl-lower alkyl, R3 and R4 are hydrogen or lower alkyl and, on the one hand, Rs is alkoxy- carbonyl or hydroxy-lower alkoxycarbonyl and R 6 is amino or mono-lower alkylamino, A representing unsubstituted or lower alkyl-substituted a,w- C -U-C--CICI- I~Z~ 71 alkylene having from 1 to 3 carbon atoms or representing a bond and B representing methylene or a bond, with the proviso that A is other than a bond when B is a bond, or a pharmaceutically acceptable salt thereof, is manufactured. 37. A process according to any one of claims 1 to 31, characterised in that a compound of formula I in which R 1 is hydrogen, alkyl having up to and including 12 carbon atoms, or hydroxy, R 2 is hydrogen, lower alkyl or halophenyl, R 3 is hydrogen or halophenyl, Ri| is hydrogen, R 5 is carboxy and R 6 is amino, A being a,w-alkylene having from 1 to 3 carbon atoms or being a bond and B in each case being methylene or a bond, with the proviso that A is other than a bond when B is a bond, or a pharmace ti- cally acceptable salt thereof, is manufactured. S 38. A process according to any one of claims 3, 6, 8, 10, 14, 18, 20, 23, 25 and 28, characterised in that a compound of formula I in which R, is hydrogen, alkyl having up to and including 12 carbon atoms, or hydroxy, R 2 is hydrogen, lower alkyl or halophenyl, R 3 is hydrogen or halophenyl, R4 is hydrogen, R 5 is lower alkoxycarbonyl or hydroxy-lower alkoxy- carbonyl and R 6 is amino or mono-lower alkylamino, with the proviso that t 1 A is other than a bond when B is a bond, or a pharmaceutically acceptable ,t salt thereof, is manufactured. t r 39. process according to any one of claims 1 to 31, characterised in that a compound of formula I in which aR is hydrogen, lower alkyl or hydroxy, R 2 is hydrogen or lower alkyl, R 3 and RT are hydrogen, Rs is lower alkoxycarbonyl and R6 is amino, A representing a,M-alkylene having from 1 to 3 carbon atoms and B representing a bond, or a pharmaceutically acceptable salt thereof, is manufactured. A process according to any one of claims 3, 6, 8, 10, 14, 18, 20, 23, and 28, characterised in that a compound of formula I in which RI is hydrogen, lower alkyl or hydroxy, Ra is hydrogen or lower alkyl, R 3 and Re are hydrogen, R 5 is lower alkoxycarbonyl and R6 is amino, A repre- senting a,w-alkylene having from 1 to 3 carbon atoms and B representing a bond, or a pharmaceutically acceptable salt thereof, is manufactured. -I ~I 72 41. A process according to any one of claims 1, 2 and 4 to 31, charac- terised in that a compound of formula I in which RI is hydroxy, Rz is hydrogen or lower alkyl, R 3 and Rit are hydrogen, R 5 is lower alkoxy- carbonyl or carboxy, Rs is amino, A is methylene and B is a bond, or a pharmaceutically acceptable salt thereof, is manufactured. 42. A process according to any one of claims 3, 6, 8, 10, 14, 18, 20, 23, 28 and 31, characterised in that a compound of formula I in which Ri is hydroxy, R2 is hydrogen or lower alkyl, R 3 and R4 are hydrogen, R5 is lower alkoxycarbonyl or carboxy and R 6 is amino, A is methylene and B is a bond, or a pharmaceutically acceptable salt thereof, is manufactured. 9 99 43. A process according to any one of claims 3, 6, 8, 10, 14, 18, 20, 23, S 25 and 28, characterised in that E-2-amino-4-methyl-5-phosphono- 3 9 pentenoic acid ethyl ester or a pharmaceutically acceptable salt thereof i s manufactured. 0 9 44. A process according to any one of claims 1, 2 and 4 to 28, charac- terised in that E-2-amino-4-methyl-5-pho3-hosphno-3-pentenoic acid or a pharmaceutically acceptable salt thereof is manufactured. 9 4 A process according to claim 29, characterised in that E-2-amino-4- I: methyl-5-phosphono-3-pentenoic acid or a pharmaceutically acceptable salt thereof is manufactured. 46. A process according to claim 1 for the manufacture of E-2-amino- 4 phosphonomethyl-3,6-heptadienoic acid and pharmaceutically acceptable salts thereof, characterised in that E-2-formylamino-4-diethylphosphono- S. methyl-3,6-heptadienoic acid methyl ester is reacted with trimethyl- iodosilane in dichloromethane and the primary product is treated with hydrochloric acid. 47. A process acc rding to any one of claims 1 to 46, characterised in that that enantiomer is produced in which the C-atom carrying the amino group R6 has the R-configuration. 73 48. A i-ocess according to any one of claims 1 tc 31, characterised in that (2R)-E-2-amino-4-methyl-5-phosphono-3-pentenoic acid or a pharma- ceutically acceptable salt thereof is manufactured. 49. A process according to any one of claims 1 to 29, characterised in that (2R)-E-2-amino-4-methyl-5-phosphono-3-pentenoic acid ethyl ester or a pharmaceutically acceptable salt thereof is manufactured. A process according to any one of claims 1 to 31, characterised in that (2R)-2-amino-4-methyl-7-phosphono-3-heptenoic acid or a pharma- ceutically acceptable salt thereof is manufactured. u 51. A process according to any one of claims 1 to 29, characterised in 4 i that (2R)-2-amino-4-methyl-5-phosphono-3-pentenoic acid ethyl ester or a pharmaceutically acceptable salt thereof is manufactured. i* 9 *s 52. A process according to any one of claims 1 to 29, characterised in pharmaceutically acceptable salt thereof is manufactured. S, 53. A process according to any one of claims 1 to 29, characterised in that E-2-amino-4-methyl-5-phosphono-3-pentenoic acid n-propyl ester or a that E-2-amino-4-mniethyl-5-phosphono-3-pentenoic acid n-butyl ester or a pharmaceutically acceptable salt thereof is manufactured. S 55. A process according to any one of claims 1 to 29, characterised in that E-2-amino-4-methyl-5-phosphono-3-pentenoic acid isobutyl ester or a S pharmaceutically acceptable salt thereof is manufactured. 56. A process according to any one of claims 1 to 29, characterised in that E-2-amino-4-methyl-5-phosphono-3-pentenoic acid n-pentyl ester or a pharmaceutically acceptable salt thereof is manufactured. A pricess according to any one of claims 1 to 29, characterised in that E-2-accino-4-methyl-5-phosphono-3-pentenoic acid isobutyl ester or a pharmaceuticclly acceptable salt thereof is manufactured. 56. A process according to any one of claims 1 to 29, characterised in that E-2-amino-4-methyl-5-phosphono-3-pentnoic acid n-pentyl ester or a pharmaceutically acceptable salt thereof is manufactured. Ir- .1 1

74- 57. A process according to any one of claims 1 to 29, characterised in that E- 2 -amino-4-methyl-5-phosphono-3-pentenoic acid n-hexyl ester or a pharmaceutically acceptable salt thereof is manufactured. 58. A process according to any one of claims 3, 5, 6, 8, 12, 15, 16, 18, 23, 26, and 28, characterised in that E-2-amino-4-methyl-5-phos- phono-3-pentenoic acid methyl ester or a pharmaceutically acceptable salt thereof is manufactured. 59. A process according to any one of claims 3, 5, 6, 8, 12, 15, 16, 18, 23, 26, and 28, characterised in that E-2-amino-4-methyl-5-phos- S phono-3-pentenoic acid ethyl ester or a pharriaceutically acceptable salt thereof is nmanufactured. A process according to any one of claims 3, 5, 6, 8, 12, 15, 16, 18, S 20, 23, 26, and 28, characterised in that E-2-amino-4-methyl-5-phos- Sphono-3-pentenoic acid n-propyl ester or a pharmaceutically acceptable salt thereof is manufactured, 61. A process according to any one of claims 3, 5, 6, 8, 12, 15, 16, 18, 23, 26, and 28, characterised in that E-2-amino-4-methyl-5-phos- phono-3-pentenoic acid n-butyl ester or a pharmaceutically acceptable salt thereof is manufactured. 62. A process according to any one of claims 3, 5, 6, 8, 12, 15, 16, 18, 23, 26, and 28, characterised in that E-2-amino-4-methyl-5-phos- phono-3-pentenoic acid isobutyl ester or a pharmaceutically acceptable salt thereof is manufactured. S, 63. A process according to any one of claims 3, 5, 6, 8, 12, 15, 16, 18, 23, 26, and 28, characterised in that E-2-amino-4-methyl-5-phos- phono-3-pentenoic acid n-pentyl ester or a pharmaceutically acceptable salt thereof is manufactured. 75 64. A process according to any one of claims 3, 5, 6, 8, 12, 15, 16, 18, 23, 26, and 28, characterised in that E-2-amino-4-methyl-5-phos- phono-3-pentenoic acid n-hexyl ester or a pharmaceutically acceptable salt thereof is manufactured. A process according to any one of claims 3, 5, 6, 8, 12, 15, 16, 18, 23, 26, 28 and 31, characterised in that 2R) -2 -amino -4-me thyl- phosphono-3-penteno4ic acid or a pharmaceutically acceptable salt thereof is manufactured. 66, (2R)-E-2-amino-L.-methyl-5-phosphono-3-pentenoic acid ethyl ester substantially free or' the (2s)-enantiomer or a pharmaceutically Ot*is 99 acceptable salt thereof. 67, Pharmaceutical composition containing (2R)-!E-2-amino-4-mehyl-5 phosphono-3-pentenoic acid ethyl ester substantially free of the (2s)-enantiomer or a pharmaceutically acceptable salt thereof and 9 customary pharmaceutical carriers, 68. A procoss for the manufacture of unsaturated amino acid compounds substantially as herein described with reference to any one of the Examples. Unsatui~atod amino acid compounds whenevar manufactuired by the process of any one of claims 1 to 65 or G8. OATE4D this 4th day of Octobe*r, 1990, CINA-CGtG\Y AG By Its PatentL Attornoys, _ARTHUR S CAVE I& CO