AU594697B2 - Substituted dipeptide amides - Google Patents

Description

00 7^ COMMONWEALTH OF AUSTRALIA At 7 PATENTS ACT 1952-1969 FORM COMPLETE SPECIFICATION (Original) Application Number: o 0 0 0 Lodged: Complete specification Lodged: Accepted: Published: Priority: Related Art: Class: Int. Class This duflaca oottdns le anwnnA'nwts made w4er SfctO 49.

and 1A oorrew r p*leag.

I I It Name of Applicant: Address of Applicant: Actual Inventor/s: Address for Service: G. D. SEARLE CO.

4711 Golf Road, Skokie, Illinois, United States of America.

BARNETT SYLVAIN PITZELE, DONALD WILLIS HANSEN, JR., ROBERT WALLIS HAMILTON; MICHAEL CLARE; and DANIEL RICHARD PILIPAUSKAS EDWIN F. WELLINGTON, 457 St. Kilda Road, Melbourne, Vic. 3004 Complete Specification for the invention entitled: "SUBSTITUTED DIPEPTIDE AMIDES" The following statement is a full description of this invention including the best method of performing it known to me/us: 1 Field of the Invention This invention provides compounds of the for; ula R2 0 R3 V W it 9 0 HN Field of the Invention Sand the pharmaceutically acceptable acid addition salts thereof repreThis invent lower alkyl, halogen, lower alkoxy orula one of R or

R,

2 3 t 3 rnR is hydrogen and the other is lower alkyl, lower alkoxy, or 10 I It 4 halkenyl, or -(CH 2 )-cycloalkyl wherein is 1 to 4 and the cycloalkyl has 3 to 8 carbon atoms; R is -(CH 2 -phenyl Srepresents an asymetric carbon when R 7 and 8 are not tha same that may be racemic or have the D or L configuration.

This invention also provides compounds where R is hydroxy, provided at least one of R 4

R

5

R

6 o R is lower alkyl. The compounds of this invention are useful analgesic agents.

r

I

j 6375K)

I,

I

t The present invention thus relates to novel dipeptide amides.

In particular, it relates to novel dipeptide derivatives of Formula 1 wich are useful as analgesic or antihypertensive "agents.

4 oo*..*ACKGROUND OF THE INVENTION 0 -0 ot In 1975, a pentapeptide, methionine enkephalin, was reported by I IHughes et al., Nature, 258, 577 (1975). This peptide is It found in many areas of the brain where it appears to act as a neurotransmitter or neuromodulator in a central pain-suppressant system. The natural peptide binds stereospecifically to partially purified brain opiate receptor sites, see for example, Bradberry et al., Nature, 260, 793 (1976). The natural peptide is also highly active in bioassays for opiate activity but exhibits only weak, fleeting analgesic activity when injected directly into the brain of the rat, see for example, Belluzi et al., Nature, 260, 625 (1976) In order to overcome the lack of in vivo activity, a number of investigators have made numerous modifications in the methionine enkephalin structure, such as substituting the glycine in the 2-position with a D-amino acid, N-methylation -3ii "I 1 p.- .1 6375K of the L-tyrosine, substituting the 4-phenylalanine with, for example, methyl or halo, modifying the C-terminus, etc., to produce enkephalin derivatives of varying p:'-operties and potencies.

Kiso, et al., "Peptide Chemistry 1981,"1: 65-70, Protein Research Foundation, Osaka, Japan (1982), disclosed the synthesis and activity of short chain enkephalin-like peptides, among them tripeptide and dipeptide alkylamides such as N-methyl tyrosine methionine sulfoxide .tc -4qyiemethylphenethylamide and tyrosine-(D) #44#4# *'iethionine sulfoxide phenylpropyl amide 44 1 OH p 0 4 CF'H 0 .4 0 0 I2 I t i At -C H; 0 (3)

-CH

3 A4 4 'avrek, et al., Peptides 2, 303, 1981 disclosed analogs of enkephalin, among them the dipeptide tyrosine-Dalanine-phenylpropylamide (Tyr-(D) Ala-PPA)

I

oH N0

*CH

3

(A)

-4ij -_nl j Y 635K f The compounds of this invention have unexpected and surprisingly superior properties when compared to the Vavrek compound. The present invention provides new enkephalin derivatives which show improved potency as analgesic agents by both oral and parenteral routes of administration. Additionally, U.S. Patent 4,316,892 relates to certain derivatives of methionine enkephalin derivatives useful as analgesic agents.

SUMMARY OF THE INVENTION t This invention encompasses analgesic agents of the formula <W 9 SH R R II 1 4 I 4 II 414441 Formula I and the pharmaceutically acceptable acid addition salts thereof wherein R 1 is lower alkoxy or -O-(CH2)n-phenyl where the phenyl may be optionally substituted with halogen, -NO 2 -NH2 or lower alkyl wherein n is 1 to 4; R 2 and R 3 represent lower alkyl, halogen, lower alkoxy or one of R or R is hydrogen and the other is lower alkyl, lower alkoxy, or halogen; R 4

R

5 R, R, and R represents halogen; R R R and R represents

I

i i

B

i Vk"i hydrogen, lower alkyl, lower alkenyl, or

-(CH

2 )m-cycloalkyl wherein m is 1 to 4 and the cycloalkyl has 3 to 8 carbon atoms; R 1 is

-(CH

2 )p-phenyl wherein p is 1 to 4; and v represents an asymmetric carbon that may be racemic or have the D or L Configuration; 7 8 w represents an asymmetric carbon when R and R are not the same that may be racemic or have the D or L configuration. This invention also encompasses compounds 1 4 where R is hydroxy, provided at least one of R ,R R or R is low.r alkyl.

,"iA preferred embodiment of the invention are compounds of ft 4 the formula t3 f

HII

H N-CH-C-NHCC.N «2 ~:p r I i Ot i'j Ttt and the pharmaceutically acceptable acid addition salts thereof wherein both R 2 and R 3 are methyl, hydrogen, or chloro; and R 1 is -O-(CH 2 )n-phenyl with the phenyl optionally substituted with halogen, -NO 2

-CN,

-NH2, or lower alkyl wherein n is 1 to 4.

By lower alkyl is meant straight or branched chain alkyl having 1 to 6 carbon atoms such as, methyl, ethyl, propyl, -6i 6375K I

I

isopropyl, butyl, isobutyl, tertiary butyl, pentyl, hexyl and isomers thereof.

By lower alkoxy is meant alkoxy containing 1 to 6 carbon atoms and having the above lower alkyl moieties.

Lower alkenyls are the above lower alkyls having one double bond.

Optionally substituted phenyl means phenyl substituted in the ortho, meta, or para position with one or more of the specified groups.

*,r'DESCRIPTION OF THE SPECIFIC EMBODIMENTS t tf I t 'he compounds described in this invention and illustrated on Examples 1-68 are synthesized by either of two o .procedures illustrated in Scheme I Route A and Scheme II Route B. Many of the compounds can be prepared by either route with the principal difference being the reaction ,equence.

6 S Route A in Scheme I and Route B in Scheme II illustrate two methods for making compounds of this invention. In '~oute A a blocked amino acid derivative X is reacted with a dialkyl amine XI by mixed anhydride coupling and the blocking group Z is removed by H 2 /Pd reduction to provide amide XII. A blocked tyrosine derivative XIII is reacted with amide XII by the mixed anhydride method to provide XIV which is separated into diastereomers, which are separately deblocked to provide compounds of formula I.

In Route B Scheme II the ester of the amino acid derivative is coupled with XIII by mixed anhydride -7ir i ;il

I

F~T Bi bjl i'" 6'375KI I coupling to provide ester XVI. This ester XVI is separated into diastereomer. For example, if XV is a D amino acid derivative and XIII is a DL tyrosine derivative, the DD and LD diastereomers are provided. The appropriate dialkylamine is then coupled to the separated diastereomer of XVII, and the product is deblocked to provide the compounds of Formula I.

In Schemes I and II, BOC refers- to tertiary butoxy 1 10 carbonyl and R through R are as previously defined. Z may be BOC or carbobenzoxy or other suitable t locking groups.

t.'Diastereomers are separated by standard techniques such as Sl 'crystalization or column chromatography.

St t I I 1 t 6

I

SCHEME I ROUTE A 0

CD)£-N

6 w 1

-NR-C-C-OH

+HNP9 Xi 1. mixed anhydride coupling 2. H 2 /Pt 0 9 HNR -C-CII ,3c\g-

XII

Soc -N t444 4 4 1~4I 4 4 44t~ '4 '44 4~ 4 #po~44 4 4 4 ii 44 4 02H

XIII

mixed anhvdride coupling

\V

4 *i '4 I 4$4 4 '4 44 4 4 4 4 44 44 44 1 I 41 44 4 1 44 144441

I

R'

separate diastereomers

XIV

hI

LD

Sdeblock

DD

X deblo ck Compounds of Formula I -9- SCHEM~E II ROUTE B 0 R HNR 6-C--C R R mixed anhydride coupling Boct t I t t

I

*000 a 4000 0 *000@~ 0 0* 0 0 '0*0 separate diastereomers saponify Diastereomer DD 2

R

Boc -N R 5 14R R 0 Diastereomer LD

I,

00 tO 0 0004 0 00 0 00 0000 0 0 0 00 0

XVII

a itt..

a Mixed anhydride coupling with NHR 9R 1 2j R -R Boc -N' 14

R

Wa3 R W19 N-C-C-NR R 0 1 R /7\8 R R DeblockI Compounds of Formula I 4 1-

;I'

-,i-i 63'75K .The analgesic activity for the compounds of the present invention is illustrated by their activity in the writhing test. The analgesic activity of the representative compounds was compared with that of a disclosed analog of enkephalin, tyrosine-(D)-alanine- phenylpropylamide.

Writhing assay. Male Charles River albino mice (CD-1/HAM/1LR) weighing between 20 and 30 grams were used. Thirty minutes after subcutaneous or intragastric administration of the test compound (0.1 ml/10 gram body ,,weight), 0.025% phenylbenzoquinone was injected 'aintraperitoneally (0.1 ml/10 gram body weight). Five inutes later, each mouse was placed in a large glass ,,,~heaker and the number of writhes that occurred in the 4 M tr subsequent ten minutes is counted. A writhe consisted of dorsoflexion of the back, extension of the hindlimbs, and I 'strong contraction of the abdominal musculature. The test S compound was considered to have produced analgesia in a S,,mouse if the number of writhes elicited by phenylbenzoquinone was equal to or less than one-half the median number of writhes recorded for the saline-treated S 'troup that day. The results were expressed as the number S111 t of mice (out of a possible ten) in which the test compound produced analgesia. The test compound was rated active if the number of writhes in the treatment group was significantly less than the number of writhes in the saline treated control group as determined by a one-way analysis of variance. If the initial test dose of mg/kg inhibited writhing in greater than 6 of 10 mice, the effect of additional doses was evaluated and an ED 50 value was calculated using a maximum likelihood function.

9-~ -va

II

'I;

j~4 i r i i i ti "i -11- 63 /bfx ft p Opiate Binding Assay, The test compounds wereO evaluated fort their ability to displace the binding of 3 H-Naloxono to opia~te receptors isolated from rnt brnin, Malo rate (Cr34 CD(SD)BR) obtanod from Charlev RivrL tboratories (Portge, MI) were aacriCicad 1by corvcal dislocation, A purified homogenate of recoptor membrano wns propared from the brains according to the method docribod by Chanc and Cuatrocasa, Chang and P. Cuatrocnaaa- Multiple Opiate Roceptorsi Enkephalina And Morphine Bind To Receptors Of Different Specificity.

2S4, 2610-2G1$ (1979).) The brains wore homogenized in volumes of 0.32 M sucroco and centrifuged twice at G,O00g 4or I5 minuteri. Following contrifugtion of th supernatants at 40,0OOxg for 30 minuten, the pallets wore ,,,resuspended in 5mM Trio-1C1 and then contrifugod at The supernatanft wan centrifuged at 401000xr,.

o-6is reauspended pellat (5mM Trio HCI) was centrifuged twice. The final pllet wan reoubpended in 2 volumes of .,tSO mM trio H01 (pH The homogenate was asayed for tr ft ftftnrOtaifl content according to the method o ft hald and Gill. F* ItZhaki and D. M. Gill. A Nicro-fliurat '146thod fo r Estimating Proteins, l p 401-410 (1964).

'Zhow binding of the toot compounds to the receptor membrane preparation was mneaaured using a modification oe the method of Pert and Snyder. Do Port and So H. Snyder, propearties of Opiatde-1cptor Dindingq in RBat Brain. NAti- Acad. 8 10_, 2243-22247 (1973) 'The rcecptor assay was run using final concentration# of I nM 3H-Naloxono and 0.5 mg/ml of homogenate protein.

6375K -5 Levorphanol (lxl0" 5 M) was used as the displacer for non-specific binding. Final concentration of the test compounds was 10-5M. The assay was run in 0.05 M tris HC1 (pH Total assay volume was 1.0 ml.

Samples were incubated at 25°C for 60 min., filtered over Whatman GF/C glass fiber filters and rinsed twice with 4 ml washes of ice-cold buffer. The filters were air-dried at 50°C for 30 minutes. After drying, 10 ml of PCS was added to the vial and the radioactivity determined using a tracor analytic Mark III liquid scintillation counter with a counting efficiency of 48%.

I''

The IC 50 value, the concentration of the test compo'unds 3 which inhibited H-Naloxone specific binding to the ,,,,#opiate receptor by 50%, were obtained from log-logit plots St"~of concentration-response curves.

,"Tho compounds can be administered in such oral dosage S,'torms as tablets, capsules, pills, powders, granules, ,,uspensions, or solutions. They may also be administered "rectally or vaginally, in such forms as suppositories or bougies. They may also be introduced in the form of ,dyedrops, intraporitonoally, subcutaneously or intramuscularly, using forms known to the pharmaceutical 1 art. In general the preferred form of administration is oral.

An effective but nontoxic quantity of the compound is employed in treatment. The dosage regimen for preventing or treating symptoms by the compounds of this invention is -13- 13751' selected in accordance with a variety of factors including the type, age, weight, sex, arid medical condition of the mammal, thp. ceverity of the symptoms, the route of administration of the particular compound employed. An ordinary skilled physician or veterinarian will readily determine and prescribe the effective amount based on the route of administration of the analgesic agent to prevent ov arrest the progress of the condition. In so proceeding, the physician or veterinarian could employ relatively low dosages at first, subsequently increasing the dose until a maximum response is obtained.

The compounds of Formula I can also be administered as pharmaceutically acceptable acid addition salts such as hydrochloride, hydrobromide, hydroiodide, sulfate, *phosphate, acetate, propionate, lactate, maleate, malate, *Succinatej tartrate and the like, Additionally, the compounds of this invention may be administered in a ,suitable hydrated form.

The compounds of this invention may be prepared by any $'#umber of methods known to those skilled in the art.- For example, the particular sequmence of reactions by which the Individual amino acids are joined to form the compounds of ''"'ormula I is generally not of critical importance, being chosen principally for convenience or for maximum yields.

moreover, the choice of activatingr reagents and conditions for joining amino acids or small peptides is not limited to those specifically described herein. Peptide intermediates anid products of this invention are typically purified by crystallization, where possible, or by column "14-

K%)

6375K chromatography. Furthermore, where racemic amino acid starting materials are employed, intermediates and products may be separated during column chromatography into diastereomers. The accompanying descriptions and figures are used to illustrate two of the possible methods used to prepare the compounds of this invention.

All NMR's are proton magnetic resonance of 80 MHz in DMSOdb with chemical shifts in I expressed as ppm from an internal TMS standard. All optical rotations are in Methanol.

Solvent stripping was under reduced pressue at or below 350 :1 .444 0 4 Example 1 ,,*3-[(1,l-dimethylethoxy)carbonyl]-0,2,6-trimethyl-DL- 4 ,"tyrosine

OCH

3 ,3 44 4 4444 4 44l II 4 #4 ,4 I1 t( 4 44 4 4i 44 I 4 T 'CII

CH

2 CH COH

II

0 Ic 1 Boc-2,6-dimethyltrosine (3.0g, 9.70 mmol) was stirred with methyl iodide (6.88g, 48.5 mmol) and potassium carbonate (5.36g,38.8 mmol) in dimethylformamide (DMF) for 17 hr in a 100 ml round-bottom single necked flask, protected from moisture with a drying tube. The reaction mixture was partitioned between water and diethyl ether. The aqueous phase was washed twice with ether and *,gp~21

I

i f i tB;. j j6375K i the organic fractions were combined, dried (MgSO4), filtered, and stripped to a white solid. Used as is NMR: methoxy singlets at 1 3.51 and 3.66.

O-Methyl-Boc-2,6-dimethyl-yrosine methyl ester (directly from the above reaction, 9.7 mmol if yield was.

quantitative) was dissolved in methanol (70 ml) and cooled in an ice bath. A solution of NaOH (3.1g, 77.6 mmol) in water (20 ml) was added. The mixture was stirred for three hours. A TLC in (1:1 Skelly B: Ethyl acetate (EtoAc) on silica slides showed that the reaction was complete. A solution of KHSO 4 (10.6g, 77.6 mmol) in water (75 ml) was added. The mixture was stripped to a lower volume to remove methanol, and extracted twice with CH2C12 (methylene chloride). The organic fractions were combined, dried (MgSO 4 filtered, and stripped.

S, The weight was 2.6g. NMR: one methoxy singlet only, at (454 3.66.

t4o Example 2 0,2,6-trimethyl-DL-tyrosyl-N-(3-phenylpropyl)-Dalaninamide, monohydrochloride SCH3 613 0 H2 -16- Ja A 100 ml 3-necked round bottom flash was set up with a magnetic stirrer, thermometer, dropping funnel (pressure equilibrating), and a y-tube. The y-tube was connected to a N 2 inlet and a drying tube outlet. The system was flushed with N 2 O-methyl-Boc-2,6-dimethyltyrosine (2.52g, 7.79 mmol) in CH 2 C1 2 30 ml) was introduced.

molecular sieves (2g, 8-12 liesh) were added. The reaction mixture was cooled to -150, and N-methylmorpholine (0.86 ml, 7.79 mmol) was added. The reaction mixture was allowed to warm to and then cooled to -600. Isobutylchloroformate (1.02 ml, 7.79 mmol) was added. The flask was then immersed in an ice bath and the reaction was run at 00 for 30 min. The flask was then immersed in a dry ice-acetone bath, and 'cooled to -700. N-methylmorpholine (0.86 ml, 7.79 mmol) ,was then added, followed by the dropwise addition of ,D-alanylphenylpropylamide hydrochloride (1.89g, 7.79 mmol) in CH 2 C12 (10 ml), keeping the reaction temperature at or below -550. After the addition was complete, the S,,reaction mixture was allowed to warm to room temperature, 4 4 and stirring was continued another 1.5 hr. The reaction *mixture was then filtered. The filtrate was washed-with

KHSO

4 The resulting aqueous layer was then washed r- ,Iith fresh CH2C1 2 The organic fractions were Ct*t4:ombined, dried (MgSO4), filtered and stripped to a hard foam (4.51g). This material was purified by column chromatography on woelm silica. The eluent was

CH

2 Cl 2 :Ethanol (2B):NH 4 OH cone (98:2:0.1).

The resulting material (4.45g) was dissolved in glacial acetic acid (50 ml) and treated with 6.8N HC1 in -17- 6375K' dioxane (12 ml). After 1.5 hr of reaction at room temperature, the mixture was stripped to a syrup. The syrup was dissolved in methanol, filtered, strir-ed, and triturated repeatedly with diethyl ether. The resulting solid was dried in a vacuum desiccator to give the product as the hydrochloride hemihydrate. Calcd for

C

2 4

H

33

N

3 0 3 HC1 1/2 H 2 0 (mw 457.02): C 63.08; H 7.72; N 9.19; Cl 7.76. Found C 62.95; H 7.37; N 8.92; Cl 7.79. [a]D +29.70. NMR: the diastereomeric mixture shows two signals for the alanyl methyl group (I 0.88,d,J=7Hz and I 1.16,d,J=7Hz), the methoxy function (I 3.61s; I 3.68s), and the 3,5 protons on the tyrosyl .,ring (I 6.50s; I 6.55s).

Fxample 3 .D,2,6-trimethyltyrosyl-N-(3-phenylpropyl)-D-alaninamide .54 Hr 3 A e o *H3 C H3 NH2 800mg of the product of Example 2 was subjected to 'column chromatography on a Whatman Partisil 20 column, 1 Using CHC13: Ethanol 2B: NH 4 0H (conc) as eluent. The f first fractions that eluted were saved for further chromatography, as explained below. Later fractions contained pure material which was stripped to dryness, giving, after vacuum desiccator drying for 16 hr, the free base 1/4 hydrate: Calc. for C 2 4

H

33

N

3 0 3 1/4

H

2 0 (mw 416.05) C 69.29; H 8.12; N 10.10. Found, C -18-

J

&K37 69.30; H 8.45; N 9.97. [a ]D .37.80 NMR: alanyl methyl group 1 1.21 d,5=7Hz; methoxy I 3.66s; on tyrosine: I 6.53s.

Example 4

O,

2 ,6-trimethyltyrosyl-N-(3-phenylpropyl).D-alaninamide Ci 3

CH

3 CH3

H

IN

NH2 0 The early fractions from the preparation of the *product of Example 3 (vide supra) were dried and applied ,a Merck silica column using eluents of CHCl 3 .,Ethanol: NH 4 0OH conc. The first-emerging isomer was 11 11 concentrated to dryness to give the free base 1/4 ~,hydrate: Calc. for C 24

H

33 N 3 0 3 1/4 H 2 0 (m.w.

,,416.04) C 69.29; H 8.12; N 10.10. Found C 69.42; H 8.31; N 9.88. [D+ 76 2 NMR: alanyl methyl signal at I '"l.06,d,J=7Hz; methoxy at I 3.66s; 3,5-diH of tyrosine at I 6.54s.

-19- 6375K Example O-ethyl-2,6-dimethyl-DL-tyrosyl-N-(3-phenylpropyl)-Dalaninamide, acetate (salt), hydrochloride (4:3:5) CH3^-i 0 NH2 0 Boc-2,6-dimethyltyrosine (1.5g, 4.85 mmol) was treated with ethyl iodide (3.78g, 24.24 mmol) and potassium carbonate (2.68g, 19.39 mmol) as described in Example 1.

4 4 The hydrolysis of the resulting ester was run as described in Example 1.

4 4 SThe mixed anhydride synthesis of Boc-protected title compound was run as described in Example 2. The resulting tBOC-dipeptide amide was purified by column chromatography t4 *.ogn woelm silica, using mixtures of 1,1,l-trichloro-2,2,2- 4 trifluoroethane and isopropanol.

4 4* The purified diastereomeric mixture was treated with 'fCl-dioxane in glacial acetic acid as described in Example The reaction mixture was stripped to a solid, dissolved in aqueous methanol, filtered through celite, and partially reduced in volume to remove some methanol.

The resulting solution was lyophilized to give the title %i i 63e75K compound as an acetic acid-water solvate:

C

25

H

35 N 0 3 1-1/4 HCl* 3/4

CUI

3 CO 2 H-1/8 H 2 0 (mw 518.44).

Caic C 61.39; H 7.68; N 8.11; Cl 8.55 Found C 61.09; H 7.28, N 8.28; Cl 8.54 p [aI=+1.

0 NMR: Alanyl methyl signals at f0.85d,J=7Hz and 11.14 d,5=7Hz; 3,5-diE of tyr-osine 16.45A, 16.53A; ethoxy function -OCH 2 f3.85q,J=7H -CH 3 11.25 t,J=7H.

Example 6 22,6,dimethyl-0-(1-methylethyl)tyrosyl-N-(3-phenylpropyl)-D- AAt ,,,Aalaninamide, hydrochloride H3M ~~T43 A~ 3l <Boc-2,6-dimethyltyrosine (1.5g, 4.90 mmol) was reacted 'With isopropyl iodide (4.16g, 24.5 mmol) in the -prese~ace of potassium carbonate (2.70g, 19.6 mmol) in DMF as described in Example 1. After 24 hr, another equal portion of isopropyl iodide, and 1.259 K2 CO 3were added. After a further 24 hr of reaction, the mixture was worked up as described in Example 1, and the mixture was subjected to column chromatography on Woelm silica, using -21- 4.1

I

6'37 ethyl acetate-hexane eluents. The NMR of the product displays restricted rotation of the phenolic isopropyl ether function (doublet of doublets at J 0.98,J=7H3, 6 protons). The ester isopropyl function signal (doublet,J=7Hz) at 11.09 shows free rotation. This material was used directly: The bis-isopropyl ester-ether (1.3g, 3.21 mmol) was treated with NaOH (1.03g, 25.7 mmol) as described in Example 1 to give the isopropyl ether free acid (1.Og).

The isopropyl ether free acid was treated under mixed anhydride conditions as described in Example 2 to give the *"*Boc-protected dipeptide amide (ether-acid 1.Og, 2.75 mmol; o a q N-methylmorpholine 0.32 ml, 2.89 mmol; 0a00 0 0 isobutylchloroformate 0.37 ml, 2.84 mmol; S.(D)alanylphenylpropylamide 0.60g, 2.89 mmol). In this O4 4 Scase, the (D)alanylphenylpropylamide was used as the free base, not the HC1 salt. Thus a second addition of .N-methylmorpholine was not necessary. The product, was subjected to column chromatography on porasil silica, *using methanol-chloroform eluents. This purification separated the two diastereomers, giving a faster (iso-F) 'and a slower (iso-S) material. Each was used (separately) '"la in the next step: The pure iso-F (494 mg.) was dissolved in glacial acetic acid (5 ml) and treated with dioxan-HC1 (6.8N, 2 ml), and consequently worked up as described in Example 2. The product was isolated as C 2 6

H

37

N

3 0 3 .1-1/8 HC1.1/2 H 2 0 mw 489.62 -22- 6 Calc C 63.78; H 8.05; N 8.58; Cl 8.15 Found C 63.60; H 7.95; N 8.35; Cl 7.93 10 4.2 0 Example 7 2,6,dimethyl-0-(l-methylethyl)tyrosyl-N-(3-phenylpropyl)-Dalaninamide, hydrochloride (8:11) 4410 4, 00 0 a I I 0 t *f t f. S

CH

3 CH3 The pure iso-S (440 mg) from Example 6 was treated in the same manner as described in Example 6 to give C26H 37

N

3 0 3 *1-3/8 HC1.1-1/8 H 2 0 (mw 510.00) Calc C 61.23; H 8.03; N 8.24; Cl 9.56 Found C 61.50; H 8.01; N 7.96; Cl 9.20 [a]D-73.30 NMR: ipr methyls I 1.19d,J=6Hz; Alanyl methyl 11.15d,J=7Hz.

V

-23t 6375K Example 8 (1..-dimethylethoxy)carbonyl]-.0-methyl-L--tyrosyl-N-(3phenyipropyl )-D-alaninamide 0,-C"H3 0 C H J 111: HjC 0 0 H3C H 3 C0 Boc-L-Tyrosine (commercially available, 10g, 35.6 mn-ol) was treated with CH 3 T (25.3g, 177.9 mmol) and 6*.2CO 3(19.7g, 142.4 minol) in DMF (150 ml) as described 9*4 4 ,in Example 1. The product (9.68g) shows NMR signals at f3.70s (phenolic methyl) and f3.60s (methyl ester), a...nd aromatic proton signals at 16.80d,J=8Hz and 0-Methyl-Boc-L-Tyrosine methyl ester (9.68g, 35.6 1 mol) was treated with NaOH (11.4g, 284.8 mmol) as described in Example 1. The product shows NMR signals at "13.70s (phenolic methyl).

r~The free acid (8.34g, 30.4 mmol) was treated with N-methylmorpholine (3.08g, 30.4 mmol), isobutyl_ chloroformate (4.15g, 30.4 mmol), and D-alanylphenylpropylamide (free base, 6.28g, 30.4 mmol) as described in Example 2.

-24- 63 The resulting oil crystallized, giving the title compound as a mixture of diastereomers: C 27

H

37 N 3 0 (mw 483.61) D 6 3 1 0 Caic C 67.06; H 7.71; 14 8.69 Found C 67.18; H 7.84; N 8.79 NMR: Ome 13.69s; arom.protons on Tyr: 16.78d,J=BHz; f7.13d,J=8Hz; Boc methyls 11.30s, D-ala methyl I 1.09d, J7Hz.

Example 9 0-methyl-L-tyrosyl-N-(3-phenylpropyl)-D-alaninamide, :,~monohydrochloride kI t 0 CH

H

*HC1 Nil 2 tNH-

I

jT,,he compound from Example 8 (3g. 6.21 mmol) was treated Ai~th glacial acetic acid (30 ml) and 6.8N HCl-dioxane (8 ml) as described in Example 2, to give the desired hydrochloride:

-C

6375K'

C

22

H

29

N

3 0 3 .HCI (mw 419,95) la)D=+44.900 Clc C 62.92; H 7.20; N 10.01; Cl 8.42 Found C 62.54; H 7.15; N 9.78; Cl 8.39 NMu O~a 13-71s; D-adr Me 11.05d,J=8Hz.

ExnmpLa O N,26,-.totramotlhyl-D-tyrosyl-N-(3-phenylpropyl)-DalaninAmido, hydrochloride oa a i,

GOAD

400 ar 0 a '120

(DD)

'Qc-f2loeM2,dimathyyroine (0,73g, 2.36 mmol) wasdissolved in DM' (20 ml) in A 100 ml round-bottomad gPonta-enwaahed Nail (9.43 mmol) was added. Tho p iAak was fitted with a drying tube and the mixture stirred, After 30 mnt mothyl iodide (2-349g, 16. mmol) was added. The mixture was atirrod for 4 hr. then more Ct1 3 1 (2,28q# 16.1 mmol) was added, After further hr,# another portion of Hall (3.33 mmol) was added, and the mixture vans utirred overnight. The mixturd was than partitiond between water and petroleum ether. The W26' aqueous fraction was washed with fresh petroleum ether, the organic fractions were combined, dried (MgSO 4 filtered and stripped. The resulting oil was subjected to column chromatography on EME silica using ethyl acetate-Skelly B eluents. This material was uqsed directly: 0,N-dimethyl-2,6-dimetlyltyrosdne methyl ester (0,66g, 1.88 mmol) was treated with NaCH (0.60go 15.0 mmol) as described in Example 1 to give the free acid (0.54g).

NMR% OMe signal at 13,66s; N-Me signal at 12,59d; t.bu signal at 11.28d. The N-Me and t-bu signal 4 s are doublets duo to restricted rotation. Each signal colllapsos to a singlet at elevated temperatures (700).

off# Vit t I* 0,N-dimethyl-2,6-dimethyltyrosine (0,54g, 1.60 mmol) #twas treated with N-methylmorpholine (0.32g, 3.20 mxnol), 'isobutylchloroformate (0,22g, 1.60 mmol), and (D)alanylplionylpropylamide hydrochloride as described in ,Example 2. The product, O,82go was subjected to column .,hromatography on Whatman MAC 20 silica using ethyl acotate-hexane eluents. The two diastereomers were ba~parated, giving a fast (iso-E), early-emerging isomer, and a slow (iso-S), late-emarging isomer.

The fact isomer (iao-i', 0.134g)p was treated, with glacial acetic acid (10 ml) and 6.8N HI~ in dioxane ml) as described in Examplo 2. The resulting solid was 27-.

6375K dissolved in water, filtered through celite, and lyophilized to give the product.

C

25

H

35

N

3 0 3 1-1/4 HCl. H 2 0 (mw 489.17) Calc C 61.39; H 7.e8; N 8.59; Cl 9,06 Found C 61.50; H 7.46; N 8.43; Cl 9.36 IOID -73.30 NMR: OMe 13.59s; IN-Me 13.04m; D-Ala Methyl /l.15d,J=7Hz, tri ""::Example 11 11 N,0,26,-tetramethyltyrosyl-', -(3-phcnylpropyl)-Dalaninamide, monohydrochloride it ,ti iii H3C t ilt 0 '1 I* I The slower isomer from Example 10 (iso-S, 0418g) was treated with glacial acetic acid (10 ml) and 6.8N HCI-dioxane (2,5 ml) as described in Example 2. The resulting solid was dissolved in aqueous methanol. The solution was reduced in volume and lyophilited. The resulting solid was disolved/susponded in methylene chloride. A small amount of ether was addedD and the -28- -11 A

'I

637 71 mixture filtered. The filtrate was concentrated to a solid which was dried in a vacuum desiccator over molecular sieves ove .:niqht. The resulting product was the title C 25

H

35

N

3 0 3 .HCl.1/2 F120 471.04) Calc C 63.75; H 7.92; N 8.92; Cl 7.53 Found C 63.85; H 7.73; N 8.81; Cl 7.71 (aD+ 4 ,,NMR: OMe 13.66s; NMe 13.01d, J=6Hz; D-ala Methyl 10.89d, J7Hz.

t "I1,2,6-trimethyl-O-(phenylmethyl)-DL~-tyrosyl-N- (3-phenyipropyl )-D-alaninamide, monohydrochloride Boc-2,6-dimethyltyrosine (5.0g, 16.2 mmol) was dissolved in DMF (100 ml), and K. C0 3 (6.69g, 48.5 mmol) was added. The mixture was stirred under a drying tube in a 250 ml round bottom single-necked flask. Benzyl bromide (11.19, 64.6 mmol) was added and the mixture stirred 24 hr. Then another portion of benzyl bromide -29- 6375K (5.46g, 31.9 mmol) and of K 2

CO

3 (3.4g, 24.6 mmol) was added and stirring was continued another 24 hr. The mixture was then partitioned between.water and ether. The aqueous phase was washed with ether. The organic fractions were combined, dried (MgSO 4 filtered, and stripped to an oil. The oil was shaken with petroleum ether. This mixture was seeded, and product crystallized rapidly. NMR: benzyl protons (4 protons) 14.99s.

Total aromatic integration 12 protons.

O-benzyl-Boc-2,6-dimethyltyrosine benzyl ester (1.73g, 3.53 mmol) was treated with sodium hydride (7.06 mmol, rinsed with petroleum ether) in DMF (22 ml) in a 100 ml 4 '"pear-shaped flask, protected with a drying tube. After ,,,,minutes, CH 3 1 (2.51g, 17.7 mmol) was added. After hr, the reaction mixture was diluted to 150 ml with t «'KHSO 4 and the mixture was extracted thrice with ether.

4 The organic fractions were combined, dried (MgSO 4 ,,filtered and stripped to an oil (2.27g). The oil was Stsubjected to column chromatography on woelm silica, with 4 8 ethyl acetate methylene chloride eluents. The isolated S' product was 0-benzyl-N-methyl-Boc-2,6-dimethyl tyrosine methyl ester: -3 0 1 6375K NMR: CO 2 Me /3.65s, OCH 2 0 15.03 (2 protons), 17.35 (5.7 protons), N-Me /2.55s, Boc-methyl asym.

doublet 11.30.

This ester (0.85g, 2.06 mmol) was hydrolyzed with NaOH (0.66g, 16.5 mmol) as described in Example 1. Product NMR: OCH 2 15.01, 17.35; N-Me /2.59s; BOC-methyls-asym doublet 11.27.

O-Benzyl-N-methyl-Boc-2,6-dimethyltyrosine (0.70g, 1.69 mmol) was treated with N-methyl morpholine (0.18g, 1.78 mmol), isobutylchloroformate (0.24g, 1.75 mmol), and ,,D-alanylphenylpropylamide (free base, 0.367g, 1.78 mmol) as described in Example 2. The resulting oil was :t ,subjected to column chromatography on Merck .silica, using .,thyl acetate-methylene chloride eluents. The resulting 'material was further purified on a 4mm chromatotron plate S(centrifugal thick layer chromatography), using Hexane-ethyl acetate eluents. The resulting mixture of diastereomers (0.45g) was subjected to hydrogenetion in tetrahydrofuran (30 ml) in the presence of palladium black (0.045g) under 60 psi of hydrogen at 250 for 22 hr.- Then another portion of palladium black (0.045g) was added, and the same conditions were reapplied for 65 hr. The resulting mixture was filtered, stripped to a solid, and subjected to column chromatography on woelm silica with eluents of ethanol: CH 2

CI

2 The first emerging compound was unchanged 0-Benzyl-N-methyl-BOC-2,6-dimethyl (DL) tyrosyl-(D)alanylphenylpropylamide. This was saved for deblocking. The next compound was the expected O-deprotected product: N-methyl-Boc-2,6-dimethyl (DL) -31il i L. __t 675J' tyrosyl-(D)alanylphenylproplamide. This mixture of diastereomers was subjected to another column chromatography on Woelm silica, using a gradient elution of ethanol CH 2 C1 2 2.5:97.5 5.5: 94.5. The first emerging compound (iso-F) and the second emerging compound (iso-S) were separately deblocked as in Examples 13 and 14.

O-Benzyl-N-methyl-BOC-2,6-dimethyl (DL)-tyrosyl-(D)-alanylphenylpropylamide was treated with methanol (1.5 ml) and 6.8N HC1 in dioxane (1 ml) for 24 hr. The mixture was evaporated in a stream of nitrogen, and dissolved in aqueous methanol. The solution was filtered through Whatman 50 filter paper, reduced in ,,,,volume in a nitrogen stream, and lyophilized. The product s C.31H 39

N

3 0 3 .HC1.3/4 H2O mw 551.64 -Calc C 67.50; H 7.58; N 7.62; Cl 6.43 ',Found C 67.44; H 7.41; N 7.47; Cl 6.69 +51.80 NMR: Benzyl methylene 14.95s, 15.03s, alanyl methyl S/1.16d,J=7Hz; 10.88d,J=7Hz.

In a separate procedure, O-benzyl-N-methyl-BOC-2, 6-dimethyl (DL) tyrosyl-(D)alanylphenylpropylamide was separated into its component diastereomers by column chromatography. Each diastereomer was treated with HC1 in methanol-dioxane as described for the mixture of -32- 6375J diastereomers. The products (separately) are the corresponding 0-benzyl-N-methyl-2, 6-dimethyl-tyrosyl- (D) alanylphenylpropylamides: C 31

H

39 N 3 0 3 .HCl mw 538.13 Caic :C 69.19; H 7.49: N 7.81; Cl 6.59 Found :C 69.50; H 7.52; N 7.92; Cl 6.66 nmr: alanyl methyl I 1.18d, J=7Hz. n-methyl 12.51. Benzyl methylene 1 4.95.

[a ID- 62 3 0 C 31

H

39

N

3 0 3 .HC1 mw 538.13 .'-Calc as for (D,D) 41,4 C 69.07; H 7.58; N 7.90; Cl 6.78 t t NMR: alanyl methyl I 0.86d, J=7Hz. N-methyl 12.50. Benzyl t hnethylene 1 5.03.

+95.5 0 Example 13 11 6-trimethyltyrosyl-N-(3-phenylpropyl.) -D-alaninamide, mbnohydrochloride

NO

-33- "1 6375k N-methyl-BOC-2, 6-dimethyltyrosyl- -alanyiphenyipropylamide (i-so F) from Example 12 was treated with methanol-HC1/dioxane as described in Example 12, except that no methanol was used after the removal of methanol-HCl/dioxane, so no reduction of volume was necessary before lyophilization. The product is j C 24

H

33

N

3 0 3 HC1.1-1/4 H 2 0 (mw 470.53) Calc C 61.26; H 7.S2; N 8.93 Found C 61.11; H 7.46; N 8.87 [D=-51.00 titNMR: Alanyl methyl 11.18d, J=7Hz.

tt S'Example 14 J N,2,6-trimethyltyrosyl-N-(3-phenylpropyl)-D-alaninamide, hydrochloride -34- 6375K N-methyl-Boc-2,6-dimethyltrosyl-(D)-alanylphenylpropylamide (iso S) from Example 12 was treated with methanol-HCl/dixoane as described in Example 12. The product is C24H33N303.1-1/8 HC1. H20 mw 470.58 Calc C 61.26; H 7.74; N 8.93; Cl 8.46 Found C 61.23; H 7.40; N 8.88; Cl 8.83 [a]D=+112 0 NMR: (D)alanyl methyl 10.90d,J=7H

Z

,,,Example 2,6-dimethyl-DL-tyrosyl-Na-methyl-N-(3-phenylpropyl)-D-alaninam ,ide, monohydrochloride Carbobenzoxy (Z)-(D)alanine (22.3g, 100 mmol) was dissolved in 'THE (300 ml). Methyl iodide (114g, 800 mmol) was added, and the mixture cooled to Sodium hydride (300 mmol, suspension in mineral oil) was added over a 1 hr period. The temperature was maintained at +100 for another hour. Another 300 ml of THF was added, and the mixture was stirred at room temperature 68 hr. Ethyl acetate (500 ml) was added to the reaction mixture, followed by H 2 0 (10 ml). This mixture was concentrated and then partitioned between water and ether. The t g375K aqueous layer was washed twice with ether, the organic fractions were combined and rinsed with saturated aqueous NaHCO 3 The aqueous fractions were combined. The organic layers were then discarded, and the aqueous fraction was acidified with citric acid solution to pH4. The acidified aqueous fraction was extracted with ethyl acetate. The organic fraction was washed twice with 5% Na 2

S

2 0 3 solution and once with water. The organic fraction was dried (MgSO 4 filtered, and stripped to an oil (22.2g). Crystallization was effected with ethyl acetate-Skelly B mixtures. NMR (CDC13): N-Me 12.89s, alanylmethyl 11.43. [a]D (Ethanol) +24.50 tott

I

N-Methyl-Z-(D)alanine (7.12g, 30.0 mmol) was treated with *N N-methyl morpholine (3.04g, 30.0 mmol), isobutylchloroformate t(4.10g, 30.0 mmol), and 3-phenylpropylamine (4.06g, 30.0 mmol), S,"as described in Example 2, giving 9.87g of a light yellow oil.

This oil was subjected to hydrogenation (60 psi H 2 in methanol at 250 with a 10% Pd/C catalyst to give the deprotected N-methyl-(D)-alanyl-phenyproplyamide as an oil (5.85g) after filtration and concentration.

N-Methyl-(D)-alanylphenylpropylamide (2.88g, 13.05 mmol) replaced (D)alanylphenylpropylamide in the mixed anhydride synthesis described in Example 2. It was reacted with the intermediate formed by the reaction of Boc-2,6-dimethyltyrosine (4.00g, 13.05 mmol) with isobutylchloroformate (3.58g, 26.1 mmol notice that two moles of isobutylchloroformate are used the second mole acts as a protecting group for the free phenol) in the presence of N-methylmorpholine (2.64g, 26.1 mmol) in methylene chloride. The final amide synthesis from -36a 6375K the mixed anhydride was run overnight at 250. After the workup described in Example 2 the material was used as is, without chromatography.

0-Isobutoxycarbonyl-Boc-2,6-(D,L)-dimethyl tyrosyl-N-methyl-(D)alanylphenylpropylamide (6.71g) was dissolved in methanol (100 ml) and stirred with K 2

CO

3 (1.98g) for 4 hr. The mixture was concentrated and partitioned between CH 2 Cl 2 and 0.5N KHSO 4 The organic layer was extracted twice with 0.5N KHSO 4 Each aqueous wash was back-washed with fresh CH2C1. The organic fractions were combined, washed thrice with saturated NaHCO 3 (backwash e.g.

with CH 2 C1 2 washed with saturated brine, dried S,,s,(Na 2

SO

4 followed by CaSO 4 filtered, and stripped to an oil (5.50g). The oil was subjected to column chromatography on 'porasil silica, using ethyl acetate-methylene chloride eluents, thus isolating the mixture of disastereomers (3.47g). This oil was triturated with Skelly B-Ether mixtures to give 3.18g of a foam.

This foam (3.03g) was treated with glacial acetic acid (24 ml) and 6.2N HCl/dioxane (9.6 ml) as described in Example 2, to Sgive the desired 2,6-dimethyl(D,L) 'tyrosyl-N-methyl-(D)-alanylphenylpropylamide hydrochloride.

C

24

H

33

N

3 0 3 .HC1.1/4 H 2 0 mw 452.51 Calc C 63.70; H 7.69; N 9.29; Cl 7.83 Found C 63.45; H 7.60; N 9.10; Cl 7.70 -37- L 6375K' H =+36.30 NMR: N-methyl-partially hidden under 12.58; alanyl methyl-fO.97d,J=7Hz; fl.l5d,J=7Hz.

I

i r

I

4. 4.

44. 4.

LLC~

4.

4.4.

C 4 4.

4. C C 4.

S 4.4.

4 4.4.

S4.S S 4.

S

C'

61375K Example 16 2 ,6-dimethyl'-DL-tyrosyl-N-methyl-N- (3-phenyilpropyl alaninai,,ide, monohydrochlo ride

*MCL

H

H21 Z-(D)-alanine (10.0g, 44.8 rnmol) was treated with N-methyl morpholine (4.54g, 44.8 mmol), isobutyichioroformate (6.12g, 44.8 mxnol), and N-methyl-3-phenylpropylanine (6.69g, 44.8 mmol) ~t~in methylene chloride as described in Example 2, giving an oil 7 A portion (4.07g) of this oil was subjected to repeated hydrogenation (60 psi H 2 in THF with a 5% Pd/C catalyst to give the deprotected (D)alanyl-N-methyl-3-phenylpropylamide Boc-2,6-dimethyltyrosine (3.54g, 11.5 mmol) and- N-methylmorpholine (1.16g, 11.5 mniol) were combined in a mixture of DMF (13 ml) and methylene chloride (13 ml). The reaction was protected by N 2 stirred 30 min, and then cooled to .500. Isobutylchloroformate (1.56g, 11.5 mmol) was then added, and the temperature was permitted to rise to -1Oo. The reaction mixture was then recooled to -500, and (D)alanyl-N-methyl-3-phenylproplyamide (2.50 g in a small amount of CH 2 Cl 2 was added. The mixture was warmed to room temperature, and stirred for 3 hr. The reaction was -39-

I

I

6375K Worked up a described in Exnmplo 2, giving 5,10g oZ foam, This roam was suspended to CH C1C, 2 ±3.toLrd, and strpped to an oil (4og). This oil was subjOcted to column chromatography on pornsil silica, using mthanol-chloofom oluonto. The product wns the mixture of Boc-protected diantcomaers (2,40g), A portion of thin mixtura (0.50q) wna toated with dioxane ml) and 6.8N BCl/dioxano (2.08 ml) for 20 hr. at 250. Tha mnixtura was strippd to a f"oamn# triturated thric with other, and driad in an abdarheldan apparatus at 780 at 0.01 torr for 2 hr, Tho product was the dociad hydrochloride hamihydrAtot

C

2 4 It 33

N

3 0 3 11C.1/2 It 2 0 mw 467,02 Caeic 63,081 11 7,72 ;N 9.191- Cl 7.76 Found C 63,07 11 7.47; N 8.96; C1 8.16 aE)Da+21.20 NMR N-mtaiylt 12.709t collapoan to 12.02d at 6001 alAnyl mathy\ /1.12mt /O.Slm; theild collapse to doublets tit 600, Tboto are probably caUeod by rostricted roatiino due to interactions o( the alanyl aPnd phonylptpyladd m*thyl functiona.

2 ,6-dichloro-4-.ehloroQthylhninolQ.

3 ,Cll~ar~rl$ E~foamn~)yf rOCU~ae m4Oa 53.8g (333 mmol) of diehloro anisole, 340 ml coc HC1, and 52.5 ml 37% formaldehyde (1.72 mo3) were heated at 500 overnight.

The reaction was diluted with H 20 and saturated brine, and extracted twice with ether, The ether phases were combined, washed with Water, saturpted NaHCO 3 saturated brine, dried with MgS0 4 and concentrated to j syrup (56g), Chroi,.atography on Waters $00 with two normal phase silica cartridges eluting with hexana at 250 ml/Min. obtained 28g white solid, Calcd. C 42,61 H 39.61 C 47.17 Found C 3961 H 2.79 CI 50.34.

CaH 7 0C1 3 (mw 22$.50).

4ia ~cbothyl (acotylaniinoo) (2,6-diclloro-4-mthoxyphonyl)methyl) propanodioato

OCR

*3 00g~ Gtoo 44 4, 08 4 00 4 0 00) 0 C11 i r

CH

2 C(C0 2 t) 2

INOCH

3 ,,.Under Ar 3,4g (137 mmol) NA was diasolvod in absolute EtoH, followed by addition of 32.3g (147 mmol) diethyl acetamidomalonate and I hr. reflux, Then 27,9V (124 mmol) of the product of txampl 17 was added and raEluxed overnight, Tho reaction wan gtiSppad and nixbd with 400 ml. 1:1 MIC10120t the organie phas ws extracted with H20 and then Sat'd BaCL, dried with MqS0 4 and concentrated to a solid (43g), The solid wm chromatoqraphad on Waters 00 with two ,normal phaee silica column, eluting with 2SY0 ethyl -41- B 1 W k-' 6375k acetate/toluene at 250 mi/min., giving 26.7g of solid, m.p.

153.50-156.40 Calcd. C 50.26 H 5.21 N 3.45 Cl1 17.45 Found: C 50.33 H 5.12 N 3.38 Cl 17.79.

C 17H21NO 6 C1 2 (mw 406.27), Example 19 2,6-dichloro-DL-tyrosine, monohydrochloride

OH

H

1 4r

CH

2

CHCO

2

H

NM

2

*HCI

23g (56.6 mmol) of the malonate adduct (Example 18), 50g (362 mmol) K 2

CO

3 and 45 g (285 mmol) phonyl selenol were refeluxd in 200 mi DM under N 2 overnight. The reaction was diluted with IL H 2 0, extracted with other, the aqueous phase as acidified with HC1 and extracted with Sat'd NaCL solution, dried with MgSO 4 and concentrated to an oil The oil was shaken with 150 mi Skolly 8 and the supernatant decanted 3X before crystallization of the oil with 100 ml CH 2 01 2 giving l1Sj of the N-acotyl amino acid as a solid. This 2.~t 6375K 7 1 compound was then refluxed in 160 ml 6N HC1 overnight, cooled and filtered to give 9.9g crystals.

Calcd: C 37.72 H 3.53 N 4.89 Cl 37.12 Found: C 37.63 H 3.45 N 4.83 Cl 36.20. C 9

HINO

3 C1 3 (mw 286.55).

Example N-[(1,l-dimethylethoxy)carbonyl]-2,6-dichloro-DL-tyrosine tll

I~

sit 11 Ji Cl

CH

2 -CHCO2H HNCOC

(CH

3 6 9.9g (4.00 mmol) of the product of Example 19 was dissolved in ml H 2 0 and the pH adjusted to 9.5 with 10% NaOH, giving a final vol. of 100 ml. t-BuOH (100 ml) and 14.5g (64 mmol) (Boc 2 )0 were added and the pH was maintained at 9.5-with NaOH. The pH was raised to 13 and the reaction was warmed to 500 to saponify O(Boc) 2 The reaction mixture was cooled, acidified to pH2 with 1M KHSO 4 and extracted with ethyl acetate. The organic phase was extracted with saturated brine, dried with MgSO 4 and concentrated. The residue was crystallized with CH 2 C1 2 to give 85g crystals.

-43- *6375K Calcd: C 48.02 H 4. 9 N 4.00 20.25 Found: C 47.36 H 4.64 N 3.75 Cl 20.53 C 14

H

17 N0 5 C1 2 (mw 350.19).

6375Ki Example 21 N-[(1,1l-dimethylethoxy)carbonyl]-2,6-dichloro-DL-tyrosyl-N-(3phenylpropyl)-D-alaninamide 0' H2 1

CMC

2 SII II CH 3 coINH CNH CNHCH2CH2CH2n ,7g (20.0 mmol) of the product of Example 20 was dissolved in ml CH Cl 2 containing 2.02g (20.0 mmol) N-Me Morpholine under N 2 cooled to -30 0 C, and 2.73g (20.00 mmol) isobutyl chloroformate was added. After 15 minutes Sg (24 mmol) D-alanylphenylpropylamide was added after raising the temperature to -20 0 C. The reaction was stirred at room temperature overnight. The reaction was diluted with 500 ml EtOAc, and extracted with 1M KHSO 4 Sat'd NaHC0 3 Sat'd tt'aCl and dried with MgSO 4 Concentrating the solution gave of foam. Chromatography on waters 500 with two normal phase silica columns eluting with 1.6% methanol/CHC13 at 250 mi/min. gave 1.3g of a fast moving isomer A and 1.lg of a slow moving isomer B. C 26

H

3 3 N 3 0 5 C1 2 (mw 538.47).

'N

6375K Isomer A. Calcd.

Found: C 58.00 H 6.18 N 7.80 C1 13.17 C 57.82 H 6.13 N 7.68 Cl 13.21 [aD= -1-90 Isomer B. Calcd. C 58.00 H 6.18 N 7.80 Cl 13.17 Found C 57.87 H 6.06 N 7.62 Cl 13.25 laD= +6.60 Example 22 ,2,6,dichlorotyrosyl-N-(3..phen-ylpropyl)-D-alan-inamide, ionohydrochioride

OH

CC1 C1 0 H28 0 CH3 *C 1.3g (2.40 mmol) of Isomer A from Example 21 was dissolved in 8 ml glacial acetic acid and 8 ml 6JHCl/Dioxane. After this, the solution was concentrated to a small volume and added to ether and filtered. 0.90g. C 21

H

26 C1 3 N 3 0 3 01/2H 2 0 (mw 483.82) *2 p637S5K Calcd: C 52.13 H 5.64 N 8.69 Cl 21.98 Found: C 51.94 H- 5.33 N 8.62 Cl 21.63 1 6 1D 570 NMR Ala methyl 1=1.18d, J=6Hz Tyi ph-H Example 23 2 6 ,dichlorotyrosyl-N-(3-peylpopyl).D..alaninamide, monohydrochloride C1 C1 0 0 C113

C,

*4 t somer B from Example 21 was treated in the same manner as p::escribed for Isomer A in Example 22, giving the title compound.

C21 H 26 C1 3 N 3 0 3 1/2H 2 0 Calcd (as in Example 22) Found: C 52.03 H 5.58 N 8.40 Cl 21.17 [aD 53.60 NMR Ala (CH 3 11.00 d (J=6Hz) Tyr (Ph H)6=6.85 0i 6375K E xampl e 24 2 4 6 -trimethyl-L-phenylalanyl-N-(3-phenylpropyl).D-alaninamide, mon ,hydrnchloride [so~mar 0 W Cl ii

I

2,4,6-Trimethylbenzyl chloride (200g, 1.19 mol) was treated the sodium salt of diethyl acetamidomalonate (274g, 1.32.

st 'mol malonate; 30.1g, 1-.31 mol sodium) as described in Example -18 giving 253g of 2,4,6-trimethyl-N-acetyl-c-carboxyethyl- 4 'phenylalanine.

This substance (241g) was dissolved in 11 of refluxing conc HCl. Refluxing continued 18 hr. Water (11) was then added, and ieflux was resumed for a short time. The reaction mixture was allowed to cool. The product crystallized out, was collected by filtration, and washed sequentially with cold 1N HCl, acetone, and ether. Recrystallization from water gave 68g of 2, 4, 6-trimethylphenylalanine.

2,4,6-trimethylphenlalaninie (62g, 254 mmol) was treated with di-t-butyldicarbonate (58g, 267 mrnol) as described in Example 20, giving 64 g of Boc-2,4..6-trimethylphenylalanine.

Boc-2,4,6-trimethylphenylalanine (7-879, 25.6 mmol) was treated with N-methylmorpholine (2.58g, 25.6 mmol), -48- 03 IbK isobutyichioroformate (3.55g, 25.6 mmol), and (D)alanylphienylpropylamide (free base, 6.0g, 25.6 mmol) as described in Example 2. The product mixture was subjected to column chromatography in porasil silica, using ethanol-methylene chloride eluents. The two diastpromers were thus separated.

The isomer emerging first from the column (2.23g) was treated with glacial acetic acid (40 ml) and 6.8N HCl/dioxane ml) as described in Example 2, giving the desired 2,4, 6-trimethyl- -Phenylalanyl- alanylph-enylpropylamide: C24 H33 N3 02' H1 (mw 432.02) .[a]ID=+115.7 0 talc: C 66.72; H 7.93; N 9.73 Found: C 66.25; H 7.85; N 9.61 NMR (CD 3 OD): 4-methyl f2.22s; alanyl methyl I 0.98d.

L.xample 2, 4,6-trimethylphenylalanyl-N- (3-phenylpropyl )-D-alaninamide, ,ionohydrochloride CH, C .4, iiN Isomer S CtH NH, (D)AIa -N H 4 'Al -49- 4"A~ V163-75K The isomer emerging last from the column chromatography (3.63g) in Example 24 was treated with glacial acetic acid ml) and 6.8N HCl/Dioxane (13 ml) as described in Exaimple 24, to give the desired 2,4,6-trimethyl-(D)--Pheniylalanyl-(D)alanylphenylpropylamide: C 24

H

33 N 3 0 2 HCl.1/4 H 2 0 (mw 436.52).[cxID=- 74.7 0 Calc: C 66.03; H 7.97; N 9.63 Found: C 66.19; H 7.96; N 9.61 NMRA (CH 3 OD): 4-methyl 12.12; alanyl methyl I 1.27d.

F8xam~le 26 N-l(1,1-direthylethoxy)carbonyl]-2,6-dimethyl-0-(phenylmethyl)- T)L-tyrosine 0 C

I

H

3 C CH 3

II

0 0-benzyl-Boc-2,6-dimethyltyrosine benzyl ester, prepared as in Example 12 (5g, 10.21 mmol), was treated with NaCH (3.27g, 81.70 mmol), as described in Example 1, giving the title compound. NMR: benzyl methylene a't 14.99s (2 protons).

S6375K Example 27 2,6-dimethyl-O-(phenylmethyl)-L-tyrosyl-N-(3-phenylpropyl)-Dalaninamide, monohydrochloride i l r. 9 O-benzyl-Boc-2,6-dimethyltyrosine (3.50g, 8.77 mmol) was treated with N-methylmorpholine (0.93g, 9.21 mmol), isobutylchoroformate (1.23g, 9.04 mmol), and D-alanylphenylpropylamide (1.90g, 9.04 mmol) as described in Example 2. The resulting material was subjected to column chromatography on porasil silica, using mixtures of methanol-chloroform as eluents. Two products were isolated, a fast (iso-F) and a slow (iso-S) isomer.

The fast moving isomer (iso-F: first to emerge from SI t column, Ig) was treated with glacial acetic acid (10 ml) and 6.8N HC1 in dioxane (3 ml) as described in Example 2. The Sresulting solid was dissolved in aqueous methanol, filtered, and lyophilized to give the title compound.

I,

6375K'

H

37 N 3 0 3 HCI..3/4 H 2 0 (mw 537.62) Calcd: Found: C 67.02; H 7.41; N 7.82; Cl 6.59 C 67.03; H 7.12; N 8.21; C1 6.84 [a]ID=+115.7 NMR: benzyl methylene: 15.03s; alanyl methyl 10.83d, J=7Hz.

Example 28 2, 6-dimethyl--(phenylmethyl) -D-tyrosyl-N- (3-phenyipropyl t alaninamide, hydrochloride flit The slow moving isomer from Example 27 (iso-S, last to emerge from the column, 1g) was treated and worked up as described for the iso-F compound in Example 27, giving the title compound C 3 0

H

3 7

N

3 0 3 1-l/8HCl.1/2H 2 0 (mw 537.67) Calcd: C 67.02; H 7.33; N 7.82; Cl 7.42 Found: C 66.84; H 7.14; N 7.98; Cl 7.15 [aD 6 9 .7 NMR: benzyl methylene: 14.95s; alanyl methyl 11.14d, J=7Hz -52- 4 A i S637j5K Example 29 N-[(l,l-dimethylethoxy)carbonyl]-2,6-dimethyl-DL-tyrosine, methyl ester

OH

CH

3

CH-

CH2CHCO2CH 3

HNCOC(CH

3 0 A 11-three-necked flask containing methanol (250 ml) and .fitted with a thermometer, a dropping funnel, and a Y-tube with ,ooa N inlet and a drying tube outlet was cooled to -700.

C 0 2 o00 0 Thionyl chloride (38.74g, 325 mmol) was added dropwise, keeping tooohe reaction temperature at or below -600. After the addition 0 0 ""was complete, the mixture was warmed to 0° *000 2,6-dimethyltyrosine hydrochloride (40g, 162 mmol) was added S oo -oand the mixture was stirred under N2 at room temperature ou vernight. The reaction mixture was then filtered to remove traces of solid, and stripped to an oil, which was triturated o 0* with ether and allowed to stand. The oil solidified overnight, and was dried in a vacuum oven at 30°, giving the methylester.

S °MR: methoxy 13.45s, 3,5-diH on aromatic ring 16.44s.

SThis product (40 g, 154 mmol) was suspended in CHC1 3 (800 ml). N-methylmorpholine (15.5 g, 16.94 ml, 154 mmol) was added, and the mixture stirred under nitrogen for 40 min.

Di-t-butyldicarbonate (33.61 g, 35.42 ml, 154 mmol) was added, and the mixture was stirred overnight. The mixture was washed -53- "i twice with water, dried (*JSO 4 )t fIilteored, and stripped. The rosidue was trituratod and filtered with hoxano, giing the title compound. NMfl; mothoxy 135o Doc-mothyls 113s 6375K Example O-t( 4 -cyanophenyl)tnetlhyl]-N-(( 1 -dimotiylctlhoxy)ca bonyl)-2,6dimethyl-DL-tyrosine 0C H3C CH 3

CH

2 -CII-C Q 2 HNOC(CI1 3 3 0 A dispersion or Nall in oil (27.3 mmol) wan weighed into a 11 round bottom flask containing a magnetic stirrer. The dispersion was washed with hexane to remove the mineral oil, anda the flask was immediately charged with tatrahydrorvran (THe) (200 ml), oc-2,6-dimathyltyroaine meth 4 'ilester (Example 29, 8g, 24.8 mmol) was added and a drying tube wan inserted.

The mixture wan stirred for 2 hr, a-Bromo-p-to3.uonitrile (8,24y, 26.8 mmol) wan then a( led, and the mixture stirred at room temperature overnigjht. A thin layer chromotogram (21 Skelly Dt Ethyl Acetate) was than run. It starting material 'Was still present, Nall dioparnion (1/2 molar amount) and alkylating agent (1/2 molar amount) ware added and the reaction run anothdr 24 hr at room tamperature. The mixture was than pourod into water (1.21) and rapidly extracted thrice with C12C126 The organic fractions were combined, dried (MgW), and nttippad to give a product (O-(p-.cyaocnzyl)'43c'-2, -dinethyltyrosinet methyl enter) which was directly hydrolyzed with Naill as doacribad in Example 1 to givo the title compound. NMRt bantyl mathylana tyresyl aromatic protons 16.60a; ban"Ayl aromatic protons contered at 17.65*

*BSA.

p.- 3 6375K (4-ch.oropjheny3.)methy I] 1- dime thyl athoxy)carbonyl]-2, 6cH 3 CH 2

CHCO

2

H

HNCOC(CH

3 3 0 Replacement of c-bromo-p-toluonitr~le in Example 30 with 4-chlorobenzyl chloride gave the title compound. M~R: benzy.

methylene 15.O0o; tyrooyl aromatic protonn 16.60s, benzyl aromatic protono all at 17.40a.

Exnmnjn 3 2 N-C (1,1"dimothylethioxy)carbonylj-2,6-dimethyl-0-( (2-mothylphenyl) wiothyl)-DL-tyrosine C~j 3 CH3 0 Replacement of a-bromo-p-toluonitrile in Example 30 with abroino-o-xyione gave the title compound. NMRi benzyl mathylene 14.9$s;, tyrosyl mothyl groups 12.25s-, bentyl, maithyl group 12.30~s.

I 6375K j Example 33 (l,1-dimethiylethoxy)carbonlyl-2,6-dimnethiyl-Q-[ (4-nitrophenyl) CH 3 CH 3

CM

2 C HCO 2

H

IINCOC (CH 3 3

II

Replacement of c-bromotoluonitrile in Example 30 with p-nitrobenzylbromide gave the title compound. NMR: benzyl inethylene 15.18s; ty2rosyl aromatic protons 16.65s; benzyl protons 17.60d, J=SHz and 18.20d, J=8Hz.

Example 34 (1,l-dimethylethoxy)carbonylj-0-( (4-fluorophenyl)methyl]-2,6dimothyl-y -yrrisiCne.-

CM

3 1 CH2 .CHC2 2

H

0 Repl.acemnent of c-bromotoluonitrile in Example 30 with 4-fluorobeny. bromide gave the title compound. NMRt bonzy.

niethyltne 15.~0a, tyroomyl aromatic protons 1660s., benzyl aromatic protons centered at 17.25, -57- Ut- 6375K Example (1,1-dimetlhylethoxy)carboiylI-2,6-dimetlhy1-O-[ (4-methylpheiyl) methyl)]-DL-tyrosine H 0 C4 3 CH 3 .H3 CH 2 CHCO 2

H

HNCOC(CH 3 )3~ 0 9 Replacement of a-br.omotoluonitrile in Example 30 with c-bromo-p-xylene gives the title compound.

Example 36 (l,1-dimethylethoxy)carbonyl]-0-f (4-(1,l-dimethylethyl)phenyl] methyl 1-2, 6-dimethyl-DL-tyrosine I i \C (C H 3 0 CH C 3 CI CHCO 111 Replacement of a-bromotoluonitrile in Example 30 with p-t-hzutylbenzy. bromde gives the title compound.

t

I

6375J Example 37 (4-chlorophenyl)met yl]-2,6-iime thyltyrosyl-N-(3-phenylpropyl) -D-alaninamide, monohydrochlorAte Cu 7 1

H

3

C

SCH

3

~H

CH

CH

2 CHCNHCHCNhCHC 2

CH

2 0 0I

NH

NFL

a HCl The product of Example 31, when exposed to the mixed anhydride condensation in Example 2, instead of 0-methyl-Boc-2,6-dimethyltyrosine, gives after workup, a mixture of diasteremoers which is separated by column chromatography. Each diastereomer is then treated with dioxane/HC/glacial acetic acid as described in Example 2, to give the two diastereomers of the title compound.

Example 38 2,6-dimethyl-0-[(2-methylphenyl)methyl]-L-tyrosyl-N- (3-phenylpropyl)-D-alaninamide, monohydrochloride 0

CH

3 T 0 Ch, II 1 ii I

.C

CH

2 CHCNHCHCNH(CH 2HCL NH 0 2 -59- 1 6375J The product of Example 32, when exposed to the mixed anhydride condensation in Example 2, instead of 0-Methyl-Boc-2,6-dimethyltyrosine, gave after workup, a mixLure of diastereomers which was separated by column chromatography.

Each diastereomer was then treated with dioxane/HCl/glacial acid as described in Example 2, to give the two diastereomars of the title compound: For the L,D diastereomer: C 31

H

39 N 3 0 3 HC1-3/4 H 2 0 (inn 551.64) Calc: C 67.50; H 7.58; N 7.62; Cl 6.43 Found: C 67.62; H 7.27; N 7.81; Cl 6.62

I

1aID +108.40. NMR: Alanyl methyl signal at f0.85, d, J=8Hz. 0-Methyl signal on benzyl group: f2.24s Example 39 2,6-dimethyl-o-[ (4-nitrophenyl)methyl]tyrosyl-N-(3-plhenylpropyl)- D-alaninamide, monohydrochloride HCl CHI 3

CH

3 CH 2 CHjNHCIIjNH (CH 2 NH2 rF d 1 6375J The product of Example 33, when exposed to the mixed anhydride condensation in Example 2, instead of O-Methyl-Boc-2,6-dimethyltyrosine, gave, after workup, a mixture of diastereomers which was separated by column chromatography. Each diasteromer was then treated with dioxane/HCl/glacial acetic acid as described in Example 2, to give the two diasteromers of the title compound having [aiD of -27.9 and 472.70 in methanol.

C

30

H

36

N

4 0 5 .HCl.1 1/4 H 2 0 (mw 591.63) Calc C 60.90; H 6.52; N 9.47; Cl 5.99 Found: C 60.58; H 6.36; N 9.46; Cl 6.27 1IMR: alanyl methyl 11.28d

C

30

H

3 6

N

4 0 5 .1 1/4 HC1. 1 1/2H 2 0(mw 605.25) Calc C 59.53; H 6.70; N 9.26; Cl 7.32 Found: C 59.13; H 6.36; N 9.05; Cl 7.27 NMR: alanyl methyl 10.95d.

i i i -61-

D

i r

I

U

Example 0- luorophenyl) methyl]-2 ,6-dimethyltyrosyl-N- (3-phenylpropyl) -D-alaninainide, monhydrochioride

CH

0 C H 3 *HCl 0 CEi CH CCHCHCMH (CH

C

2 2 3Q NH 0

I

44 44 4 4444 4 4 4 4 4 4*~ 4414 4.

44 4 4 o c The product of Example 34, when exposed to the mixed anhydride condensation in Example 2, instead of 0-Methyl-Boc-2 ,6-dimethyltyrosine, gave after workup, a mixture of diastereomers which was separated by column chromatography. Each diastereorner was then treated with dioxane/HCI/glacial acid as described in Example 2, to give the two diastereomers of the title compound having [a]D of -64.2O0 and 94.00 in methanol.

r 3: )i 12 I 6375J Example 41 2,6-dimethyl-o-[(4-methylphenyl)methyl]tyrosyl-N-(3-phenylpropyl) -D-alaninarnide, monohydrochioride 0

C

2 oa .RC1 CH ti 1 FI 4 4 tI It C!

CH')

CH 2 C-CNHCHCNH

(CR

j II(D) 11 2 3-

NH

The product of Example 35, when exposed to the mixed anhydride condensation in Example 2, instead of O-Methyl-Boc-2,6-dimethyltyrosine, gives after workup, a mixture of diastereomers which is separated by column chromatography. Each diastereomer is then treated with dioxane/HC/glacial acid as described in Example 2, to give the two diastereomers of the title compound.

Example 42 [4-(l,1-dimethylethyl)phenyl]methyl-2,6-dimethyltyrosyl N-(3-henylpropyl)-D-alaninamide, morohydrochioride i f

(CH

3 3

CH

3 .HC1 CH3 CH 2 CHCNHCHCNH (CH 2 11(D) i 23 NH 2 M*i 6375J The product of Example 36, when exposed to the mixed Anhydride condensation in Example 2, instead of 0-Methyl-Boc-26-dmettyltyrosin, gave after workup, a mixture Of diastereomers which was separated by column chromatography.

Each diastereomer was then treated with. dioxane/HC1/glacial acid as described in Example 2, to give the two diastereomers of the title compound.

C

3 4H 5

N

3 0 3 .HCl.1/2H 2 0 mw 589.22 Caic t C 69.31; 8.04; N 7.13- C116.02 Foundi C 68,98; H- 7.55; N 7.23; CI 6.42 IWR alanyl mathyl 11.Sd o a i!

B

sll-t j taIDnSO-.O (tD) C 3 e 4 1 5

N

3 0 3 'HC.1/2110 mw 589.22 041c i as Foundt C 69,25; H. 7.93; N 7.36; Cl 6.14 NMRi Aanyl mathyl .Sd taigD +102.40 637

A

Example 43 0- (4-ccyanoplienyl )metilyl i -2 ,5-d imetly y ltyro syl 3 pheny lpropyl)- D'alani~namide, monohycrochioride

CICN

3 C 3

CH

2 C!1CNHvic"NH (CU1 2 )3 *HC 11

C

NH2 The product of Example 30, when exposed to the mixed anhydride condensation in Example 2, instead of 0-Methyl-Boc-2,6-dimethyltyrosine, gave after workup, a mixture of diastereomrs which was separated by column chromatography.

Each diastereomer was then treated with dioxane/HCI/glacial acid as described in Example 2, to give the two diastereomers iof the title compound having [a]D of -74.4' and +90,20 in methanol.

C

31

H

3

N

4 0 3 .1 1/8 HC1.1/2 H 2 0 mw 562.69 Cala i C 66.17; H 6.83; N 9.96; Cl 7.09 4 Foun: C C65,80; H 6,67; N 9,84; Cl 6.86 NM1: Alanine methyl groupt 11.16d

C

31 1 3 6

N

4 0 3 HC1.1/4H 2 0 mw 553.62 6375J Calc C 67.26; H 6.83;N 10.12; Cl 6.40 Found: C 66.96; H 6.96; N 10.09; C1 6.59 NMR: Alanine methyl group: 10.81d.

Examole 44 4 -aminophenyl)mnethyl]-2,6-dimthyltyrosyl-N-(3-phenylpropyl)- D-alaninamide, monohydrochloride O CH 2H 0 Q

NH

2 2

O

CH

3

CH

CH

CH

2 CHC HCHC NH (CH 2 *HCL 11(D) 1i

NH

The title compound of Example 39 was treated with hydrogen in the presence of palladium on carbon in methanol. The mixture was filtered and concentrated to low volume. The resulting material was triturated with ether and dried to give -the title compound having (cuD of -60.0O in methanol

C

3 0

H

38

N

4 0 3 .HCI.1/2H 2 0 mw 548-13 Cale C 65.74; H 7.36; N 10.22; Cl 6.47 0 65,94; H 7.09; N 9.91; C1 6.55 NMR: alanyl methyl group 11.16d.

3 6375J Example 2R-[(cyclopropylmethyl)amino]-N-(3-phenylpropyl)propanamide CH2- CH CH2NHHCNH (CH 2

(D)

A mixture of (D)Alanylphenylpropylamide (0.825g, 4.00 mmol), NaHCO 3 (l.00g, 1.20 mmol), bromomethylcyclopropane (0.64g, 4.74 mmol) and 10 ml Ethanol (2B) was heated at reflux for 8 hrs with stirring. The reaction mixture was partitioned between ethyl acetate and water, The organic layer was separated and dried over Na 2

SO

4 The solvent was removed under reduced pressure and the resultant oil was purified by column chromatography on a Porasil column eluting with 3/96.8/0.2; MeOH/CHC13/NH4OH. NMR: (CDC13) shift (D) Ala 11.28d, J=9Hz. Cyclopropylmethyl; 10 to 0.25, complex, 2H 10.30 to 0.65, complex, 2H; 10.65 to 1.00, complex, 1H; 1 d of d 12.39 J =3.5Hz, J 2 =8Hz.

A sample of the above product was dissolved in methanol and treated with sufficient HC1 gas dissolved in 2-propanol to render acid. Anhydrous ether was added to the point of turbidity and the mixture cooled to 00. The resultant solid was filtered and dried at reduced pressure under an inert atmosphere.

l j 6375J NMR: shift of (D)Ala methyl 11.43(d)3H, J=9Hz cyclopropyl methyl: 10.20 to 0.'70, 4H, complex; 1 0.80 to 1.30, 1H, complex; 2.4 to 2.9, 2H hidden Analysis: Calc for C 16

H

24

N

2 0*HC1 C 64.74; H 8.49; N 9.44; Cl 11.94 Found: C 64.63; H 8.37; N 9.44; Cl 12.11.

Example 46 N-((1,1-dimethylethoxy)carbonyl]-2,6-dimethyl-DL-tyrosyl-Na- (cyclopropylmethyl)-N-(3-phenylpropyl)-D-alaninamide

OH

CH

3 C 3 CH CH O 2 C H/ I I I i 3 CH CHC N CHC H(CH) 2 (D) HNICCC (CH 3 3

O

The title compound of Example 45 replaced (D)alanylphenylpropylamide in the mixed anhydride synthesis 4 t described in Example 2. It was reacted using Boc-2,6-dimethyltyrosine (2.97g, 9.60 mmol), isobutylchloroformate (1.31g, 9.60 mmol) and N-Methyl-morpholine (0.98g, 9.60 mmol). Dimethylformamide r eplaced methylene chloride as the solvent. The reaction mixture was worked up as in Example 2 and the resultant foam (4.4g) was purified by column chromatography on Merck silica eluting with 3% methanol-methylenechloride.

6:3 75 J Example 47 2 6 -dime thyl-DL-tyrosyl-N (cyclopropymetyl (3phenylpropyl)-D-alaninamide, monohydrochioride

CH

CH ii -O N CH1C -:HCCI(

CH

3 3 CXI

NHC

The product from Example 46 (0.1g, 0.924 mmol) was treated with glacial acetic acid (Sml) and 62N HC/dioane (1.36 ml) as described in Example 2 to give the desired 2,6-dinethyl(D,L) "tyro syl -N-cyclopropylme thyl (D -alanyIpHenypropylamde ,r :hydrochloride.

IN H C H4

P

1 1 2 7

H

3 7

N

3 0 3 .~l.CH 2 1 MW 497.08 Calc: C 65.24; H 7.91; N 8.45; Cl 7.13 '-Found: C 65.19; H 7.73; N 8.42; CL 7.20 13.60 NMR: (CDCl 3 cyclopropyl: /0 to complex, SH; 12.25 2H partially hidden by 2,6 Dimethyl groups #1<tyrosine) (D)ala methyl shifts /1.23 and 1.41 3H.

It 6375~J Example 48 (l,1-dimethyleth-oxy)carbonyl]-N-(2-propenyl)-D-alanine CH 2 CH=CH 2 (CCH JCC H Allyl iodide (6.72 g, 40.0 mmol) replaced methyl iodide and Boc-(D)-alanine (1.89g, 1.0.0 mmol) replaced Z-(D)alanine in the reaction of Example 15. They were reacted using sodium hydrid~e (30.0 mmol, 50% suspension in mineral oil) and THF (30 ml).

of oil was obtained using the procedure and work-up of o xample NqMR: (CDC 3 alanylmethyl 11.45: N-allyl 13.70 to 4.00, 4 4.95 to 5.30, 2H; [a ID Methanol 43.30 O #0 4 44t

I

6,375 J Example 49 1, 1-dimethylethyl [1R-methiyl-2-oxo-2-[ (3-phenylpropyl)aminoj ethyll (2-propenyJ~carbamate

C-

2 CH=CH 2 CH 3 COCIN CH-- CNH (CH 2 3 1 N-Allyl-Boc-(D)-alanine (Example 48) (9.58g, 41.8 mmol) was treated with N-methyl morpholine (4.27g, 41.8 mnmol), isobutylchlorformate (5.71g, 41.8 mxnol) and 3-phenyipropylamine 41.8 mmol) as described in Example 2 giving 18.83 g of l a light oil.

4 4 4NMR (CDCl 3 alanylmethyl 11.35; N-allyl; 13.70 to 93.90, 2H; 4.95 to 5.30, 211; 5.50 to 6.10; 1H [aI]D Methanol +26.30.- Example "N-(3phenylpropyl)2R(2propenylamino)propanamide 4 CH 2 C.C-iNH-c..Cm (CH) H 0 6375J; The product from Example 49 (13.83g, 39.9 mmol) was treated with glacial acetic acid (100 ml) and 6.2N HCl/dioxane (58.7 ml) as decribed in Example 2 to give the desired N-allyl-D-alanylphenylpropylamide hydrochloride. This was converted to the base by dissolving in the minimal amount of water, treating with sufficient sold NaHCO 3 to render alkaline and extracting with methylene chloride. The extract was dried over Na 2

SO

4 and the solvent removed under reduced 7 pressure to give 8.98 g of a light oil.

It 1k Example 51 N[(1,1-dimethylethoxy)carbonyl]-2,6-dimethyltyrosyl-N-(3-phenyl propyl)-Na-(2-propenyl)-Dalaninamide OH

IC

S I I I i t C H3C

CH

3

CH

3 o

CH

2 CHC'CH

CNH(CH

2 S(D)

C

II CH2CH=CH 2

(CH

3 3C-O-C-NH N-Allyl-(D)-alanylphenylpropylamide (5.00g, 20.3 mmol) replaced alanyl-phenylpropylamide in the mixed anhydride Synthesis described in Example 2. It was reacted using toc-2,6-dimethyl-tyrosine (6.28g, 20.3 mmol) N-methyl morpholine (2.05g, 20.3 mmol) and isobutylchloroformate (2.77g, 20.3 mmol). Dimethylformamide replaced CH 2 Cl 2 as the 63'75J solvent. The reaction mixture was worked up as in Example 2 and the resultant oil (10.62 g) was purified by column chromatography on Woelm silica eluting with 3 to methanol-methylene chloride and the diasteromers were separated: NMR: (CDC13) First isomer from the column: alanyl methyl 10.44 and 1.00 to 1.50 (rotamers) 3H; N-allyl (propen"!) 13.50 to 3.80, 2H; 4.80 to 5.25, 2H; 5.25 to 5.75 1H.

NMR(CDCl 3 Second isomer from the column; D-alanyl methyl 11.00 to 1.50 (rotamers) .3H; N-allyl (propenyl) 3.50 to 3.80, 2H; 4.80 to 5.21, 2H; 5.25 to 5.75 1H.

,Example 52 St -C D 4I H N D H 0 H

H

33 1 .OOg of the fast moving isomer from Example 51 was treated .,,ith glacial acetic acid (6 ml) and 6.2 N Hcl/dioxan (2.7 ml) as described in Example 2 to give the desired (D) 2,6-dimethyltyrosyl-N-(3-phenylpropyl-Na-[2-propenyl]-Dalaninamide hydrochloride *ii

I

63751J C 26 H 3 SN 3 0 3 HCl 1/2 H 2 0 MW 483.05 Caic: C,64.65; H, 7.72; N, 8.70; Cl Found: C, 64.49; H, 7.61; N, 8.74; Cl 7.34.

7. [aI]D NMR: (DMSO d 6 ISO F-(D)alanyl methyl 10.47 1.13 (Rotamers), 3H; N-allyl (propenyl) J4.50 to 5.50, 2H: 5.25-5.85, 1H.

The slower moving fraction was treated as described directly above to yield the L,D isomer.

C

26

H

35 N 3 0 3 HC1.1/2H 2 0 mw 483.05 Calc :C 64.65; H 7.72; N 8.70; Ci. 7.34 Anel :C 64.87; H 7.56; N 8.60; Cl 7.66 +117.9 0 14MR: (D)ala methyl 1=1.03d Example 53: Phenylmethyl 6-cimethyl-4-(phenylmethoxy)phenyl Imethyl] 5-oxo-2.-phenyl-3-oxazolidinecarboxylate -74- ;:X~i 6375J 2,6-dimethyltyrosine hydrochloride (20.0g) was dissolved in water (1 liter). The pH was adjusted to 8.5 (10% NaOH in and benzylchloroformate (14.3 g) was added in one portion. The pH was maintained between 7 and 8 with the aqueous NaOH for two hours. The reaction mixture was then acidified (Conc HC1) and extracted with ethyl acetate. The aqueous layer was saturated with NaCI, and then extracted three times with ethyl acetate. The organic fractions were combined, dried (Na 2 SO4), filtered, and stripped to an oil. This oil was triturated with ether/hexane, giving a solid. The solid was ground up (mortar pestle) and dried overnight at 420 and 110 torr.

A portion of the resulting N-carbobenzoxy 6-dimethyltyrosine (15g, 43.7 mmol) was dissolved in dimethylformamide DMF (200 ml) and treated with benzyl bromide (29.9g, 20.0 ml, 174.7 mmol) and potassium carbonate (18.1g, 131.1 mmol) at room temperature for 16 hr. The reaction mixture was diluted to 1.7 liter with H 2 0, and then extracted S twice with CH2C1 2 The organic fractions were combined, dried (MgSO 4 filtered and stripped to an oil. This oil was subjected to column chromatography on slica gel, using ethyl acetate-hexane eluent. The major product was N-Z-2,6-dimethyltyrosine benzyl ester. This material (11.1g, t 25.6 mmol) was used directly in the next step.

<t3Sodium hydride dispersion in mineral oil (28.2 mmol) was washed with petroleum ether and suspended in DMF (200 ml). All of the N-Z-2,6-dimethyltyrosine benzyl ester was added thereto. After i -vC 27 1 6375J min of stirring, benzyl bromide (3.20 ml, 4.60 g, 26.9 mmol) was added all at once. The mixture was stirred 16 hr, and then worked up as described above, giving 13 g of dibenzylated product.

The resulting O-benzyl-N-Z-2, 6-dimethyltyrosine benzyl ester was hydrolyzed to the free acid with methanolic sodium hydroxide as described in Example 1, giving 12.1 g of O-benzyl-N-Z-2,6-dimethyltyrosine. This acid (12 g, 27.7 mmol) was placed in a 500 ml round bottom single neck flask fitted with a Soxhlet extractor which was filled with 5A molecular sieves (8-12 mesh beads). The flask was also charged with 1,1,1-trichloroethane (350 ml), benzaldehyde (5.62 ml, 5.86 g, t '.55.4 mmol), and toluene-sulfonic acid monohydrate (5.27 g, 27.7 t ;mmol). The flask was immersed in an oil bath (bath temperature 1200) and the mixture was refluxed for 16 hr. The reaction was then cooled and the mixture was washed with sat NaHCO 3 The Saqueous wash was back-washed twice wth CH 2 C1 2 All the organic fractions were combined, dried (MgSO 4 filtered, "'stripped, and subjected to column chromatography on silica with eluents of ethyl acetate-hexane. The title compound was "':isolated as a solid which was washed with ethanol and then ether. NMR: aromatic proton 14.21 m, benzyhydryl proton under benzyl peaks 14.99. Integration shows three benzyl (idene) groups.

ctL 'Si *;3

SI

3.3 Ap J3 ibJ 1 Example 54

I

i Si i phenylmethyl 4-[[2,6-dimethyl-4-(phenylmethoxy)phenyl]methyl]- 4 -methyl-5-oxo-2-phenyl-3-oxazolidinecarboxylate A 500 ml round bottom flask fitted with a magnetic stirrer, thermometer, dropping funnel, and y-tube (connected to an N 2 inlet and a drying tube outlet) was charged with dry THF (150 ml), which was cooled (dry ice bath) to -600. A solution of potassium hexamethyldislazane in toluene (0.653 M, 21.0 ml, Callery Chemical Company,. Callery, PA) was added all at once.

The solution was cooled back to -700, and a solution of the title compound of Example 53 (5.5g, 10.6 mmol) in THF (100 ml) .'was added dropwise rapidly, keeping the reaction temperature at 'or below -62o. The mixture was then stirred in the cold bath f" for 30 min, and the cold bath was then removed. Stirring at S room temperature for another 30 min elevated the reaction tempature to -12o. The reaction mixture was then re-immersed in the cold bath, and the temperature returned to Methyl iodide (1.05 ml, 2.40 g, 16.9 mmol) was added al at once, and after another 10 min the cold bath was removed. The reaction mixture was permitted to warm to room temperature, and 3 hr Safter removal of the cold bath the mixture was partitioned ,between a mixture of H20 (200 ml), 0.5 N KHSO 4 (50 ml), saturated brine (200 ml) and ether (200 ml). The aqueous phase was washed with ether, the organic fractions were combined, dried (MgSO 4 filtered, and stripped to an oil. The oil was -77- -i G3753 Applied to silica gl column chromatography on using ethyl AcetLQte1-hexane luent# giving the title compound, NMR; methyl group at 12,71 A, 3 protons, S,2, 26-trimothyl-4-(p lhonylmthoxy)ca.

([(phenylmothoxy)carbonylJ amino jbonzenapropanoic acid The title compound of Example 54 (2,42 q) wan dianolved in S ml of III C11 2 02 1 methanol, and added to mathanolic NaOH (1N, 100 ml) Aftor 3 hr of stirring, the mixture was concentrated to 75 ml, diluted to 500 ml with water, and extracted twica with other to remove non-acidic contaminants. The aqueous phase was made acidic with 0.,i XHS0 4 and then extracted tour times with CH1 2 C1 2 The CH 2 cl fractienn wore combined, drt.ad (MgS0 4 )1 filtered and otripped to give the title compound (1.76q). NMRin methyl group at 12.75.

t,2, 6-trrimthyl-N-f (phoniylmothoxy)cArbonyl-0- (phonyltnothyl) tyrosyl-I- (3-pheanypropy). alaninainido The titlo compound ot ExAmplt $5 wan reacted under mixed anhydride conditiona ani dencribed in Exmp). 2 to givd thd Z-protacted dipeptide amide (acid 1,75 g, 3.0 1nnol;

'I'T

V470m "1 6375J N-methylmorpholine 0.42 g, 4.11 mmol; isobutylchloroformate 0.53 ml, 4.03 mmol;' (D)-al anylphenylpropyj amide 0.85 g, 4.11 mmol). The product, 2,32 g, was subjected to column chromatography on silica gel, using ethanol; metfhyl tert-butyt ether: ammonium hydroxide e2uent. The two diastereomers were thus separated, giving a 4aster-amorging and a slower-emerging isomer.

Ex mpl 5 7 If 0 4 rr H -4H'~SI D -I a,2,6 trimothyl 0-tyrosyl-N-(3-phenylpropyl) D-alaninamide The moro rapidly emerging title i8omer of Example 56 (1.0 g) wan hydrogonolyzod in mothanol with a palladium black catalyst (0.31 g) at room temperatura for 17 hr at 60 psi of hydrogen.

The mixture was kilterod to remove the catalyst, re-filtered through to remove finen partclrn, and otrppd. The residue Was dissolved in othanoI-wator-mothanol, filtered, rieduced in volume with a nitrogen stream, and LyophiliOzd to give the title comnpound, the Dl, 0, isomer. NMR- ti-mothyl group at 12.11 and 2.26 for two rotamars; alanyl methyl at 1 1.21 d, Jm7z' WD a -23.20. For C 2 4

H

3 3 N.0 3 1/4 112 (mW 416.5)z tU 6375J Calc: C, 69.29; H, 8.12; N, 10.10 Found: C, 69.24; H, 8.11; h" 9.81 Example 58 a 2, 6-trimethyl-EC-tyrosyl N- (3 -phenyptpopyl) -D-alani namide The more slowly emerging title isomer of example 565 was treated as described in example 56 to give the title compound, the L, D isomer.

NMR: 11.10 d, J= 7 HZ*(a]D 90.10.

'E'Or C 24

H

33

N

3 0 3 (mw 411.54): "'Calc: C, 70.04; H, 8.08; N, 102,1 round: C, 70,41; 8, 7.95; N, 10.21 4 'xam~le_ 59 hnal1esic properties of the substituted diptotide amides.

The receptor binding and biological properties of the following -ompounds of this invention are illustrated in Table utilizing the previously described opiate binding and writhing assay. Tb standard screening dose for the writhing assay was mg/kg sic, and p.o. The standard screening dose for the opiate binding assay was 10 Molar.

*aM -2 6375J Table 1 ANALGESIC PROPERTIES Opi atea Binding Example Writhing Subc.

Mouse Oral 2.9xl0 7 4.2x10 7 7.5x10 8 1.3x10 7 4.7x10 8 6.1x10 7 Inactive 3.6x10 6 1.8x10" 6 1. 4x10" 7 6.0x10 10 3.0xlO0 7 7.6x10" 9 2,0x10" 6 3.6x10" 7 2.2x10 8 Active Active Active Active Inactive Active Active Active Active Active Active Active Active Active Active Active Active Active Active Inactive Inactive Active Active Active Inactive Inactive Active Inactive Active Inactive Active Active

IC

50 expressed as moles/liter b Active refers to the effect of the screening dose mg/kg).

The matter contained in each of the following claims is to be read as part of the general description of the present invention.

Claims (25)

1. A compound of the formula: r Is. 0 W 11 9 C c N-R 1 6 8 110 R R R and the pharmaceutically acceptable acid addition salts thereof wherein R 1 is lower alkoxy or -0-(CH 2 )n-phenyl where the phenyl may be optionally substituted with halogen, -NO2,-CN,-NH 2 or lower alkyl wherein n is 1 to 4; R and 3 R represent lower alkyl, halogen, lower alkoxy or one of R or R 3 is hydrogen and the other is lower alkyl, lower 4 5 7 8 9 alkoxy, or halogen; R R R R and R represent 6 hydrogen or lower alkyl, R represents hydrogen, lower alkyl, lower alkenyl, or -(CH 2 )m-cycloalkyl wherein m is 1 to 4 and the cycloalkyl has 3 to 8 carbon atoms; R1 is -(CH 2 )p-phenyl wherein p is 1 to 4; and v represents an asymmetric carbon that may be racemic or have the D or L Configuration; -82- 6375J w represents an asymmetric carbon when R 7 and R are not the same that may be racemic or have the D or L configuration; 1 4 5 6 and R may be hydroxy when at least one of R 4 R 5 R or R is lower alkyl.

2. A compound according to Claim 1 of the formula: H 3 C CH 4 R 1. ;I kc l" and the pharmaceutically acceptable acid addition salts thereof wherein both R 1 is lower alkoxy or -0-(CH 2 )n-phenyl with ,,the phenyl optionally substituted with halogen, -NO 2 -CN, 4 5 NH 2 or lower alkyl wherein n is 1 to 4; R R and R are hydrogen or lower alkyl; and the optical isomer 'thereof.

3. The compound, according to Claim 2, which is O-edime-2,6-dimethyltyrosyl-N-(3-phenylpropyl)-D- alaninamide, and the acetate or hydrochlorlde. -83- 1 6375J

4. The compound accord~ing to Claim 2, which is 2 ,6,dimethyl-0-(1-methylethyl)tyrosyl-N-(3--pheniylpropyl)-D- alaninamide, hydrochloride. A compound according to Claim 2, which is N,0,2, 6, tetr ame thyl -D -tyro syl -pbenylpropyl.-D- alaninamide, hydrochloride.

6. A compound according to Claim 2, which is N, 0,2, 6, -tetramethyltyrosyl-N- (3-phienyipropyl) -D- alaninamide, monohydrochioride.

7. A compound according to Claim 2, which is N,2,6-trimethyl--0-(phenylmethyl)-tyrosyi-N-(3- phenylpropyl) -D-alaninamide, hydrochloride.

8. A compound according to Claim 2, which is 2, 6-dimethyl-o- (phenylmethyl )-tyrosyl-N- (3-plhenylpropyl alaninamide, hydrochloride. 9, A compound according to Claim 2, which is (4-chlorophienyl)methyl]-2, 6-dimethyltyr-yN-3- phenylpropyl) -D-alaninamide, hydrochloride. A compound according to Claim 2, which is 2, 6-dimethyl-0-( (2-methylphenyl)mnethyl]tyrosyl-N-(3- phenylpropyl) -D-alaninamide, hydrochloride. -84- 63 75 J

11. A compound according to Claim 2, which is 2,6-dimethyl-o-[ (4-nitrophienyl)methyl]tyrosyl-N-(3- phenylpropyl)-D-alaninanide, hydrochloride.

12. A compound according to Claim 2, which is 0-i (4-fluor7ophenyl)methyll-2,6-dimethyltyrosyl-N-(3- phenylpropyl)-D-alaninamide, hydrochloride.

13. A compound according to Claim 2, which is 2,6-dimethyl-0-[ (4-methylphenyl)methyl]tyrosyl-N-(3- phenylpropyl)-D-alaninamide, hydrochloride.

14. A compound according to Claim 2, which is 0-i [4-(1,1--;dimethylethyl)phenyl]methylJ-2,6--dimethyltyrosyl- N- (3-phenylpropyl )-D-alaninamide, hydrochloride. A compound according to Claim 2, which is (4-cyanophenyl)methyl]-2,6-dimethyltyrosyl-N-(3- phenylpropyl)-D-alaninamide, hydrochloride.

16. A compound according to Claim 1 of the formula 0 HN C-C-N c 14 5 0 6 CH 3 R R 3 RP 1 63 75 J d 7 4 5 6 9 wherein one of R R R and R 9 are lower alkyl and the other are hydrogen.

17. A compound according to Claim 16 which is N,2,6-trimethyltyrosyl-N-(3-phenylpropyl)-D-alaninamide, hydrochloride.

18. A compound according to Claim 16 which is 2, 6-dimethyl-DL-tyrosyl-Na.-methyl-N-(3-phenylpropyl) -D- alaninamide, hydrochloride.

19. A compound according to Claim 16, which is 2, 6-dimethiyl-DL-tyrosyl-N-methyl-N- (3-phenylpropyl alaninamile, hydrochloride.

20. A compound according to Claim 16 which is a,2,6 trimethy. D-tyrosyl-N- (3-phenyipropyl) D-alaninamide. I II 4 I I £4 I

21. 4t A compound according to Claim 16 which is a,2,6-trimethyl-L-tyrosyl-N-(3-phenylpropyl)-D-alaninamide.

22. A compound of the formula H 2 N4 H _77, 6Z 675 J, arnd the pharmaceutically acceptable acid addition salts thereof wherein'R 6is 2-propenyl or cyclopropylmethyl.

23. A compound according to Claim 22 which is 2,6-dimethyl-DL-tyrosyl-N-(cyclopropylmethyl)-N-(3- phenylpropyl)-D-alaninamide, hydrochloride.

24.' A compound according to Claim 22 which is 2, 6-dimethyltyrosyl-N-(3-phenylpropyl-Na-[2-propenyl]-D- alaniriamide, hydrochloride. The compound according to Claim I which is 2,6,dichlorotyrosyl-N-(3-phenylpropyl)-D-alaninamide, hydrochloride.

26. 2,4, 6-trimethylphenylalanyl-N-(3-phenylpropyl)-D-alaninamide, hydrochloride.

27. A process for the preparation of a compound or salt as defined in any one of Claims 1 to 26, which comprises: reacting a blocked amino acid derivative of the formula W 0 Z-NR-CCO X R R wherein R 6 R 7 ,R 8 and W are defined in Claim 1, and Z is tertiary butoxy carbonyl or carboberizoxy or other suitable blocking group, with an amine of the formula HNR 9R 9 10 wherein R 9 and R are as defined in Claim 1, by mixed anhydride coupling, followed by the removal of the blocking group Z to provide the amide of the formula W R 9 6 I HNR C-C-N XII R 7 8 6 7 8 9 wherein R R R R R and W are as defined above; (ii) reacting the amide of formula XII above with a blocked tyrosine derivative of the formula R 2 R 1 ZR R 3 p d o fo XI II SiR3 V R3 SZ-N COOH R 0 R R 1 2 3 4 5 6 7 8 9 wherein R R R R R and V are as defined in Claim 1, and Z is as defined above, by mixed anhydride coupling to provide the blocked -88- Speptide of the formula 2 1 R W 0 4 6 _11 -9 1 0 X I V NR -C-C-NR R Z-N R5 7-\8 R 0 R R R 1 2 3 4 5 6 7 8 9 wherein R R R R R R R R R R, V, W and Z are as defined above; and -88- (iii) separating the blocked peptide of formula XIV into diastereomers followed by the removal of the blocking group Z from the separated diastereomers to provide the desired compound or salt.

28. A process for the preparation of a compound or salt as defined in any one of Claims 1 to 26, which comprises: reacting an ester of an amino acid of the formula WO 6 0 HNR -C-C-O-Alk XV 7 \8 R R 6 7 8 wherein R R R and W are as defined in Claim 1, and Alk identifies an alkyl radical, with a blocked tyrosine derivative of the formula 2 R 1 C, IXIII V R Z--N R COOH 1 1 3 N wherein R R R R R and V are as defined in Claim 1, and Z is tertiary butoxy carbonyl or carbobenzoxy or other suitable blocking group, by mixed anhydride coupling to provide the ester of the formula -89- ''f l Ar XVI w 0 6 II -NR -C-C-OAlk 7O R 0 R R Z-N R' 1 4 R wherein R, R 2 R 3 R 4 R R 6 R R R V, W, Z and Alk are as defined above; (ii) separating the ester of formula XVI into diastereomers, followed by coupling the separated diastereomer with an appropriate amine of the formula HNR R0 9 10 wherein R and R 0 are as defined in Claim 1 to provide a blocked peptide of the formula R 2 R 1 rss: rrt *Ir fs i Li iC I' Z- N XVIII wherein R 1 R 2 R 3 R R 5 R 6 R 7 R R 9 R V, W and Z are as defined above; and (iii) removing the blocking group Z from the blocked peptide of the formula XVIII to provide the desired compound or salt. IL) .P i I ij j

29. A compound or salt as defined in any one of Claims 1 to 26 when obtained by the process of Claim 27. A compound or salt as defined in any one of Claims 1 to 26 when obtained by the process of Claim 28. 31, A pharmaceutical composition comprised of a pharmaceutical carrier in combination with at least one compound or salt according to any one of Claims 1 to 26, 29 and

32. A method of promoting an analge.ia or antihypertonsive effect in a mammal in need thereof comprising administering thereto an analgosically or anti- hyportonsivoly effective amount of at least one compound or salt according to any one o Claims 1 to 26, 29 and 33, A method accordIng to Claim 32 wherein said compound or salt is administered in the form of a composition according to Claim 31. DATED this 12th day of Auqust, A.D. 1986 ARd "R By ita Patent AttorneyOV EDWIN P. WBELLINTON Ptllow of the tnatiuto of Patent Attorneyi of Australia .91- ft i- L(0= j sc iua w I~t m w *iiilli.111ujiiir W