GB2156349A

GB2156349A - Thiatriazine derivatives

Info

Publication number: GB2156349A
Application number: GB08507661A
Authority: GB
Inventors: Jeffrey Daniel Michael; Barry Clive Ross; Simon John Cousins
Original assignee: Hoechst UK Ltd
Current assignee: Sanofi Aventis UK Holdings Ltd
Priority date: 1984-03-27
Filing date: 1985-03-25
Publication date: 1985-10-09
Also published as: GB8507661D0

Abstract

Novel compounds of formula I <IMAGE> in which formula R represents a hydrogen atom, a straight or branched chain alkyl group having from 1 to 4 carbon atoms, a phenyl group or a phenalkyl group, the alkyl moiety of which has a straight or branched chain and from 1 to 4 carbon atoms, an alkyl, phenyl or phenalkyl group being unsubstituted or substituted; W and Z, which may be the same or different, each represents a group E-(CH2)n - X - (CH2)m - NH- in which E represents a phenyl, imidazolyl, thiazolyl, furyl, thienyl, or pyridyl radical, which radicals may be unsubstituted or may have one or two specified substituents, or one of W and Z represents a group E - (CH2)n - X - (CH2)m - NH- as defined above, and the other represents a hydrogen atom; a straight or branched chain alkyl group having from 1 to 6 carbon atoms; a phenyl group; an -OR<3> group in which R<3> represents a straight or branched chain alkyl group having from 1 to 4 carbon atoms; or an NR<4>R<5> group in which R<4> and R<5>, which may be the same or different, each represents a hydrogen atom, an unsubstituted or substituted straight or branched chain alkyl group having from 1 to 6 carbon atoms, or a phenyl group; X represents -O- or -S-; n represents 0 or 1; and m represents 2, 3 or 4, are histamine H-2 antagonists. <IMAGE>

Description

SPECIFICATION Thiatriazine derivatives The present invention relates to thiatriazine derivatives which have histamine H-2 antagonist activity. The invention also relates to processes for the preparation of these derivatives, to pharmaceutical preparations comprising them, and to their use.

Histamine is one of a number of naturally occurring physiologically active substances which are thought to interact with specific receptors. In the case of histamine, there are at least two types: one is called the H-l receptor (Ash and Schild, Brit. J. Pharmac. 1966, 27, 427), and the other is called the H-2 receptor (Black et al Nature 1972, 236, 385). The action of histamine at the H-l receptor, for example, stimulation of bronchial and gastro-intestinal smooth muscle, is blocked by the compounds generally known as "antihistamines", but which are now also called histamine H-l antagonists, for example, mepyramine.The action of histamine at the H-2 receptors, for example, stimulation of gastric acid secretion and heart rate, is not blocked by mepyramine but is blocked by other compounds, for example, burimamide and cimetidine.

Histamine H-2 antagonists may be used to treat those conditions resulting from stimulation by histamine of H-2 receptors, either alone, for example, in inhibiting gastric acid secretion and thus treating its sequelae, for example, gastric and peptic ulcers; or together with H-l antagonists, for example, in allergic and certain inflammatory conditions.

The presence invention provides compounds of formula I, which are histamine H-2 antagonists:

in which formula R represents a hydrogen atom, a straight or branched chain alkyl group having from 1 to 4 carbon atoms, a phenyl group or a phenalkyl group, the alkyl moiety of which has a straight or branched chain and from 1 to 4 carbon atoms, an alkyl, phenyl or phenalkyl group being unsubstituted or substituted by one or more substituents, which may be the same or different, for example, by one or two substituents, especially by one substituent, selected from halogen atoms, straight and branched chain alkyl groups having from 1 to 4 carbon atoms, straight and branched chain alkoxy groups having from 1 to 4 carbon atoms, nitro and trifluoromethyl groups;; W and Z, which may be the same or different, each represents a group E-(CH2) - X - (CH2),, - NH- in which E represents a phenyl, imidazolyl, thiazolyl, furyl, thienyl, or phyridyl radical, which radicals may be unsubstituted or may have one or two substituents, selected from straight and branched chain alkyl groups having from 1 to 4 carbon atoms, guanidino and mono-alkyl guanidino groups, the alkyl moiety of which has a straight or branched chain and from 1 to 4 carbon atoms, and groups of the formula II

in which Q represents an alkylene group having from 1 to 4 carbon atoms, and Ri and R2, which may be the same or different, each represents a hydrogen atom, a straight or branched chain alkyl group having from 1 to 4 carbon atoms or, together with the nitrogen atom to which they are attached, R1 and R2 form a 4 to 8-membered ring which may contain an oxygen atom or another nitrogen atom, which nitrogen atom may have an alkyl substituent having from 1 to 4 carbon atoms, or one of W and Z represents a group E - (Ch2)n - X - (CH2)m - NH- as defined above, and the other represents a hydrogen atom; a straight branched chain alkyl group having from 1 to 6 carbon atoms; a phenyl group; an -OR3 group in which R3 represents a straight or branched chain alkyl group having from 1 to 4 carbon atoms; or an NR4R5 group in which R4 and R5, which may be the same or different, each represents a hydrogen atom, an unsubstituted or substituted straight or branched chain alkyl group having from 1 to 6 carbon atoms, or a phenyl group; X represents -O- or -S-; n represents 0 or 1; and m represents 2, 3 or 4.

This invention also provides salts of a compound of formula I, especially physiologically tolerable salts.

Alkyl groups in the present specification may be branched or unbranched, and alkyl groups, for example, alkyl groups R4 and R5, may be unsubstituted or substituted, for example, by one or more, for exam ple, one or two, groups selected from (i) OR6 groups in which R6 represents a straight or branched chain alkyl group having from 1 to 6 carbon atoms; (ii) cycloalkyl groups having from 3 to 7 carbon atoms; (iii) -NR7 R6 groups in which R7 and R6, which may be the same or different, each represents a hydrogen atom, a straight or branched chain alkyl group having from 1 to 4 carbon atoms, a phenyl group or an acyl group having from 1 to 4 carbon atoms in the alkyl moiety, and R7 and R8 together with the nitrogen atom to which they are attached may form a 5 or 6 membered ring;; (iv) -COOR9 groups in which R9 represents a straight or branched chain alkyl group having from 1 to 4 carbon atoms; (v) -CONR7 Rs groups in which R7 and Rg are defined above; (vi) alkylsulphonyl groups having from 1 to 4 carbon atoms in the alkyl moiety and phenylsulphonyl groups; (vii) cyano and nitro groups; (viii) phenyl groups which may be substituted by one or two substituents, which may be the same or different, selected from alkyl, alkoxy, methylenedioxy, phenoxy, halogen, dimethylaminomethyl, trifluoromethyl, nitro, cyano, sulphonic acid, sulphonamide, amino, mono- alkylamino and di-alkylamino groups, an alkyl moiety having a straight or branched chain and from 1 to 4 carbon atoms;; (ix) aromatic and non-aromatic heterocyclic groups having from 5 to 8 ring members and one or two hetero-atoms selected from oxygen, sulphur and nitrogen atoms, and optionally having an alkyl substituent having from 1 to 4 carbon atoms on a ring nitrogen atom, for example, a furyl, tetrahydrofuryl, thienyl, pyridyl, dihydropyranyl, pyrrolidinyl, N-lower alkyl-pyrrolidinyl, or piperidyl group.

A phenyl group other than a phenyl group E (which is as defined above), may be unsubstituted or substituted as defined in (viii) above.

It will be understood that the structure given above for formula I is only one of several possible tautomeric and isomeric representations. The present invention includes all possible tautomeric and isomeric forms of compounds of the general formula 1.

In the present specification the term "lower" is used to denote a group having from 1 to 4 carbon atoms. The term "halogen" denotes chlorine, bromine, iodine and fluorine. The term "known" is used herein to mean in actual use in the art or described in the literature of the art.

It will be appreciated by a worker skilled in the art that a combination of substituents that are incompatible for steric reasons or because of potential inter-reactions should not be chosen. The worker will also use his normal discretion in the number of substituents chosen.

The present invention also provides a process for the production of a compound of formula 1, which comprises reacting a 1,2,4,6-thiatriazine of formula IIIA or IIIB

in which R, W and Z are as defined above, W and L having any of the meanings given above, and L represents a halogen atom, an alkoxy, phenoxy or phenylalkoxy group, an alkylthio, phenylthio or phenylalkylthio group, an alkyl-sulphinyl, phenylsulphinyl or phenalkylsulphinyl group, or an alkylsulphonyl, phenylsulphonyl or phenylalkyl- sulphonyl group, in which groups an alkyl group or alkyl moiety has a straight or branched chain and from 1 to 4 carbon atoms, and a phenyl group may be substituted as defined in (viii) above, with a compound of the general formula IV E-(CH2)n-X-(CH2) m-NH2 IV in which E, X, m and n are as defined for formula 1, and, if desired, carrying out any one or more of the following reactions in any desired order: (i) converting a group R into another group R, (ii) converting an acid addition salt of formula I into the corresponding free base or converting a free base into an acid addition salt, or (iii) in a resulting compound of formula I in which one of the groups W and Z represents a group NR4R5, converting this group into another group NR4R5.

In addition to serving as a substitutent in the final product, R4 may also act as a protecting group in the above chemical transformations and may subsequently be removed, for example, by hydrogenolysis or by acid or base catalysed hydrolysis to provide a compound of the general formula I in which W or Z is a group -NHR5 or -NH2. Protecting groups which come within the definition of R4 are t-butyl and benzyl groups, for example.

Compound IV is generally reacted with compound IIIA or with compound IIIB in a solvent or diluent, preferably in an alcohol, acetone, acetonitrile or DMF. The reaction temperature is, for example, within the range of from 0 to 80"C, depending on the nature of the leaving group L. Generally when L is a halogen atom, an alkylsulphinyl group or a substituted phenoxy group, the reaction occurs rapidly at 0 to 20"C, but when L is an alkylthio or alkoxy group, elevated reaction temperatures, for example, in the range of from 50 to 100"C, for example, from 60 to 80"C are preferred.

The compound of formula IV is reacted in the form of the free base, as shown. If it is initially present in the form of an acid addition salt, for example, as the hydrochloride or hydrobromide, this is converted into the free base during or, preferably, before reaction with compound IIIA or IIIB. Conversion is carried out with an organic or inorganic base, for example, sodium hydroxide or potassium hydroxide, or a tertiary amine, for example, triethylamine.

A compound of formula I may be converted into its salt form in the usual manner by reaction with an acid. Examples of physiologically tolerable acid addition salts are those with hydrobromic, hydrochloric, sulphuric, acetic, malonic, maleic, fumaric, succinic, citric, tartaric and isethionic acids.

A compound of formula I in the form of an acid addition salt may be converted into the free base form by reaction with a base in the usual manner.

A number of compounds of the type represented by formula IV are known, see, for example, GB Specification 2,001,624A; U.S. Patent 3,950,333; U.S. Patent 4,128,658; and Belgian Patents 867,106 and 875,846, and the others may be prepared analogously.

Some examples of the thiatriazine intermediates represented by formula IIIB are disclosed in U.S. Patent 4,013,447, DE-OS 2,943,703, DE-OS 3,134,143, DE-OS 2,933,889, and EPA 0,029,908.

However, many of the specific intermediates of formula IlIB and all of the compounds of formula IIIA have not been described previously, and form part of the present invention. Some thiatriazines of the general formula lIlA may be prepared as shown in Scheme 1.

Scheme I

in which R and R4 are as defined above; Rio represents an alkoxy, phenoxy, phenylalkoxy, alkylthio, phenylthio or phenylalkylthio group as defined above for L, for example, a methoxy, benzyloxy or methylthio group; and R1l-Y represents an alkylating agent, for example, R11 represents an alkyl or phenalkyl group, for example, a lower alkyl group or a phenyl-lower alkyl group, for example, a methyl or benzyl group, and Y represents a haloqen atom, for example. an iodine or bromine atom. R11-Y represents, for example, methyl iodide or benzyl bromide. When R" is different from and distinguishable from R'O, the reiative positions ot R and R4NH- on the thiatriazine ring of compound XII can be distinguished.

A compound V is reacted with an isothiocyanate VI in an inert solvent, for example, acetonitrile or a chlorinated hydrocarbon, for example, methylene chloride, preferably at a temperature within the range of from 20 to 50"C, to give a compound of formula VII, which is alkylated with an alkylating agent VIII, preferably at a temperature in the range of from 20 to 50"C and generally in a solvent, for example, acetonitrile, an ether, for example, THF or, preferably, an alcohol, for example, methanol or ethanol, to give the compound of formula IX. Compound IX is then reacted with an alkylaminosulphonyl chloride of formula X, in the presence of a tertiary base, for example, triethylamine, to give compound XI.The reaction is generally carried out in a solvent, for example, acetonitrile, an ether, or a chlorinated hydrocarbon, for example, methylene chloride, preferably at a temperature of from 0 to 20"C. Compound Xl is cyclised by heating, for example, at a temperature within the range of from 60 to 1600C, preferably from 60 to 800C, in an aprotic solvent, for example, dioxane, acetonitrile or diglyme, preferably in the presence of an organic base, for example, a tertiary base, for example, triethylamine, to give the thiatriazine of formula XII.

Alkylaminosulphonyl chlorides of formula X are known, see for example, J. Org. Chem., 41, 4028 (1976).

Other thiatriazines of general formula IIIA may be prepared as shown in Scheme II Scheme II

in which R and RlO are as defined above, and RI? represents a hydrogen atom, a straight or branched chain alkyl group having from 1 to 6 carbon atoms, a phenyl group or an -OR3 group, in which R3 represents a lower alkyl group, especially a methyl or ethyl group. An alkyl or phenyl group may be substituted as defined above.

A compound of formula XIII is reacted with an alkylaminosulphonyl chloride of formula X, preferably in the presence of a tertiary base, for example, triethylamine, to give compound XIV. The reaction is generally carried out in a solvent, for example, acetonitrile, an ether, or a chlorinated hydrocarbon, for example, methylene chloride, preferably at a temperature in the range of from 0 to 200C. Compound XIV is generally reacted with one equivalent of anhydrous ammonia, preferably in an inert solvent, for example, tetrahydrofuran or dioxane, preferably at a temperature in the range of from 0 to 20"C to give compound XV, which is cyclised to the thiatriazine XVII by reaction with ortho ester XVI.This reaction may be carried out using an excess of the ortho ester as solvent or, preferably, using an inert solvent, for example, acetonitrile, tetrahydrofuran, dioxane or diglyme, preferably at an elevated temperature, for example, from 80 to 160 C.

Imidocarbonates and dithioimidocarbonates of formula XIII are known, see for example, Z. Chem. 8, 459-460, (1968), Beilsteing E113 page 156, and Bull. inst. recherches biol. unic. Perm, 6, (10), 517-522, (1929).

Thiatriazines of formula XII or formula XVII in which R'O represents an alkylthio, phenylthio or phenylalkylthio group may be converted to other compounds of formula IIIA, for example, by oxidation of the thio group to the corresponding sulphinyl or sulphonyl group, or by replacement of the alkylthio, phenylthio or phenylalkylthio group by a halogen atom, especially a chlorine atom, for example, as shown in Scheme Ill, in which Y represents a halogen atom, for example, a chlorine atom, R'3 represents an alkyl, phenyl or phenylalkyl group, for example, a lower alkyl, phenyl or benzyl group, and x represents 1 or 2.

Scheme I I I

Such a conversion may be carried out by known methods, for example, by oxidising the sulphide group using, for example, a peracid, for example, m-chloroperbenzoic acid; hydrogen peroxide; or a periodate, perborate or permanganate salt. Replacement of an alkylthio or arylthio group by a halogen atom may be carried out, for example, by treating compound XVIII with excess chlorine or bromine, for example, by treatment with elemental chlorine or bromine, or with a compound capable of yielding the desired halogen, for example, phosphorus pentachloride. The halogenation is generally carried out in an inert solvent, for example, a chlorinated hydrocarbon, an ether or an ester, for example, chloroform, tetrahydro- furan or ethyl acetate, generally at a temperature within the range of from 20 to 100"C, and preferably in the presence of a catalyst, for example, anhydrous zinc chloride.

Certain thiatriazines of formula IIIA and of formula IlIB may be prepared from a dichlorothiatriazine of formula XXII as shown below in Scheme IV, in which R, R4, RO and Rr3 are as defined above: Scheme IV

Treatment of a compound of formula XXI (which is known, see for example, DE-OS 2,943,703), with excess phosphorus pentachloride gives the dichlorothiatriazine of formula XXII.This reaction is carried out in an inert solvent, for example, a chlorinated hydrocarbon, for example, 1,2-dichloroethane, or phosphorus oxychloride, generally at a temperature within the range of from 80 to 105"C. Compound XXII is then reacted with a primary or secondary amine XXIII in an aprotic solvent, for example, diethyl ether, dichloromethane or acetonitrile, generally at a temperature within the range of from -40 to +20"C to give a mixture of isomers XXIV and XXV, which can be separated by known methods, for example, by fractional crystallisation or by chromatography.Higher temperatures, for example, for 0 to 20"C generally give a mixture of the two isomers, whereas lowering the temperature to the reaction between compounds XXII and XXIII to within the range of from -40 to -20 C gives predominantly the isomer of formula XXIV. Isomers XXIV and XXV fall within the general formulae IIIA and IlIB respectively. Compounds of the formulae Xl, XII, XIV, XV, XVII, XVIII, XIX, XX, XXII, XXIV and XXV are new and form part of the present invention (see also below for compounds XIV and XV).

The present invention also includes all possible tautomeric and stereoisomeric forms of those compounds of the invention that can form such isomers.

Examples of preferred compounds of formula I are the following; (1) R = methyl, Z = methylamino, W = E-(CH2)n -X -(CH2) - NH- in which E = [2-[(2-Guanidino-4-thiazolyl), n = 1, X = S, and m = 2 i.e. 3-[2-[(2-Guanidino-4-thiazolyl)methylthio]ethyl]amino-5-methylamino-6- methyl-1 ,2,4,6-thiatriazine-1 ,1-dioxide.

(2) R = methyl, Z = tert.-butylamino, W = E-(CH2) - X -(CH2) - NH- in which E = [2-[(2-Guanidino-4thiazolyl), n = 1, X = S, and m = 2 i.e. [2-[(2-Guanidino-4-thiazolyl)methylthioiethyl]amino-5-tert.-buty- lamino-6-methyl-1,2,4,6-thiatriazine-1 ,1 -dioxide.

(3) R = methyl, Z = tert.-butylamino, W = E-(CH2) - X -(CH,),- NH- in which E = [3-[3-(1-Piperidinylme- thylphenyl), n = O, X = 0, and m = 3 i.e.

3-[3-[3-(1 -Piperidinylmethyl)phenoxy]propyl]amino-5-tert.-butylamino-6-methyl-1 ,2,4,6-thiatriazine-1,1- dioxide.

(4) R = methyl, W = tert.butylamino, Z = E-(CH2)n - X -(CH,(, - NH- in which E = [2-[(2-Guanidino-4thiazolyl), n = 1, X = S, and m = 2 i.e. 2-Methyl-3-[2-[(2-guanidino-4-thiazolyl)methylthio]-ethyl]-amino-5- tert.-butylamino-1 ,2,4,6-thiatriazine-1 1-dioxide and the hydrochloride salt thereof.

(5) R = methyl, W = dimethylamino, Z = E-(CH2)" - X -(CH,) - NH- in which E = [2-[(2-Guanidino-4thiazolyl), n = 1, X = S, and m = 2 i.e. 2-Methyl-3-[2-[(2-guanidino-4-thiazolyl)methylthio] ethyl]amino-5dimethylamino-1 ,2,4,6-thiatriazine-1 dioxide.

(6) R = methyl, W = methoxy, Z = E-(CH2)n - X -(CH2) m - NH- in which E = [2-[(2-Guanidino-4-thiazolyl), n = 1, X = S, and m = 2 i.e. 2-Methyl-3-[2-[(2-guanidino-4-thiazolyl)methylthio]-ethyl]amino-5-methoxy- 1 ,2,4,6-thiatriazine-1 dioxide.

(7) R = methyl, W = phenyl, Z ; E-(CH2)n - X - (CH2) - NH- in which E = [2-[(2-Guanidino-4-thiazolyl), n = 1, X = S, and m = 2 i.e. 2-Methyl-3-[2-[(2-guanidino-4-thiazolyl)methylthio]-ethyl]amino-5-phenyl-1,2,4,6- thiatriazine-i i-dioxide.

(8) R = methyl, Z = amino, W = E-(CH2)n - X - (CH?) - NH- in which E = [2-[2-Guanidino-4-thiazolyl), n = 1, X = S, and m = 2 i.e. 3-[2-[(2-Guanidino-4-thiazolyl)methylthio]ethyl]amino-5-amino-6-methyl-1,2,4,6- thiatriazine-l,l -dioxide, and the trifluoroacetic acid salt thereof.

(9) R = methyl, W = amino, Z = E-(CH2)n - X - (CH2) m - NH- in which E = [2-[(2-Guanidino-4-thiazolyl), n = 1, X = S, and m = 2 i.e. 2-Methyl-3-[2-[(2-guanidino-4-thiazolyl)methylthio)ethyl]amino-5-amino-1,2,4,6- thiatriazine-i,i-dioxide.

(10) R = methyl, Z = amino, W = E-(CH2)n - X - (CH2) Izm - NH- in which E = [3-[3-(1-Piperidinyl-methyl- phenyl), n = 0, X = 0, and m = 3 i.e. 3-[3-[3-(i-Piperidinylmethyl)phenoxyjpropyl]-amino- 5-amino-6 methyl-i ,2,4,6-thiatriazine-i ,i -dioxide, and its trifluoroacetic acid salt.

(11) R = methyl, W = amino, Z = E-(CH2)n - X - (Ch2)m - NH- in which E = [3-[3-(1-Piperidinyl-methyl- phenyl), n = 0, X = 0, and m = 3 i.e. 2-Methyl-3-[3-[3-(1-piperidinylrnethyl)phenoxy]-propyl] amino amino-l ,2,4,6-thiatriazine-1 ,l-dioxide, and its trifluoroacetic acid salt.

The present invention further provides a pharmaceutical preparation which comprises a compound of the general formula I or a physiologically tolerable salt thereof as active ingredient, in admixture or conjunction with a pharmaceutically suitable carrier. The preparation may be in a form suitable for enteral or parenteral administration, for example, for oral or intravenous administration. The preparation may be in unit dosage form, for example, as tablets or capsules, or in unit or multiple dose ampoules or vials. From 0.1 to 10 mg of the active substance may be administered per kg body weight. A preparation of the invention may also comprise one or more pharmaceutically active substances, for example, histamine H1 antagonists.

The present invention also provides a compound of the general formula I for use as a medicament, especially for use as a histamine H-2 antagonist, and further provides a method of treating conditions resulting from stimulation by histamine of H-2 receptors, either alone, for example, in inhibiting gastric acid secretion and thus treating its sequelae, for example, gastric and peptic ulcers, or together with H-l antagonists, for example, in treating allergic and certain inflammatory conditions.

The present invention further provides the use of a compound of formula I for the manufacture of a medicament for the treatment of conditions arising from stimulation by histamine of histamine H-2 re ceptors.

The present invention further provides compounds of formula XXXV

in which R31 and R32, which may be the same or different, each represents a hydrogen atom, a straight or branched chain alkyl group having from 1 to 4 carbon atoms, a cycloalkyl group having from 3 to 7 carbon atoms, a phenyl group, or a phenalkyl group having from 1 to 4 carbon atoms in the alkyl moiety, wherein an alkyl, cycloalkyl, phenyl or phenalkyl group may be unsubstituted or substituted by one or more substituents, which may be the same or different, for example, by one or two substituents, especially by one substituent, selected from halogen atoms, straight or branched chain alkyl groups having from 1 to 4 carbon atoms, straight or branched chain alkoxy groups having from 1 to 4 carbon atoms, and nitro and trifluoromethyl groups; or Rll and R32 together with the nitrogen atom to which they are attached, form a 4- to 7-membered ring which may contain one or more further hetero-atoms, for example, selected from nitrogen, oxygen and sulphur atoms; L3 represents a group -XR46 in which X represents an oxygen or sulphur atom and R46 represents a straight or branched chain alkyl group having from 1 to 4 carbon atoms, an unsubstituted or substituted phenyl group, or an unsubstituted or substituted phenalkyl group having from 1 to 4 carbon atoms in the alkyl moiety, wherein a phenyl or phenalkyl group may be substituted by one or two, and especially by one substituent, selected from alkyl, alkoxy, methylenedioxy, phenoxy, halogen, dialkylaminoalkyl (especially dimethylamino- methyl), trifluoromethyl, nitro, cyano, sulphonic acid, sulphonamide, amino, and monoand di-alkylamino groups, an alkyl moiety having a straight or branched chain and from 1 to 4 carbon atoms, and R42 and R43, which may be the same or different, each represents a hydrogen atom, a straight or branched chain alkyl group having from 1 to 4 carbon atoms, a phenyl group or a phenalkyl group, the alkyl moiety of which has a straight or branched chain and from 1 to 4 carbon atoms, wherein an alkyl, phenyl or phenyalkyl group may be unsubstituted or substituted by one or more substituents, which may be the same or different, for example, by one or two substituents, especially by one substituent, selected from halogen atoms, straight and branched chain alkyl groups having from 1 to 4 carbon atoms, straight and branched chain alkoxy groups having from 1 to 4 carbon atoms, nitro and trifluoromethyl groups.

Compounds of formula XXXV may exist in various isomeric and tautomeric forms. The present invention includes all isomeric and tautomeric forms of a compound of formula XXXV.

In the present specification, the term "lower denotes groups having up to 4 carbon atoms, and any alkyl group can have a straight or branched chain.

In a compound of formula XXXV, R31 preferably represents a hydrogen atom, and R32 preferably represents a hydrogen atom or a lower alkyl group, especially a methyl group or an ethyl group. Particularly preferred are those compounds in which R31 represents a hydrogen atom and R32 represents a methyl group and especially preferred are those compounds in which R31 and R32 both represent hydrogen atoms.

When X in L3 represents a sulphur atom, L3 preferably represents a lower alkylthio group, especially a methylthio group, or a phenylthio group. When X represents an oxygen atom, L3 preferably represents a substituted phenoxy group, especially a mono-substituted phenoxy group, for example, a nitro-substituted phenoxy group, for example, an ortho-nitrophenoxy group.

The present invention provides a process for the production of a compound of a formula XXXV as defined above, which comprises reacting a compound of formula XXXI

in which R31 and R32 are as defined above, and L? and L4, which may be the same or different, each represents a group -XR46 in which X represents an oxygen or sulphur atom and R46 represents a straight or branched chain alkyl group having from 1 to 4 carbon atoms, an unsubstituted or substituted phenyl group, or an unsubstituted or substituted phenalkyl group having from 1 to 4 carbon atoms in the alkyl moiety, wherein a phenyl or phenalkyl group may be substituted by one or two, and especially by one substituent, selected from alkyl, alkoxy, methylenedioxy, phenoxy, halogen, dialkylaminoalkyl (especially dimethylamino- methyl), trifluoromethyl, nitro, cyano, sulphonic acid, sulphonamide, amino, and monoand di-alkylamino groups, an alkyl moiety having a straight or branched chain and from 1 to 4 carbon atoms, with the proviso that in L3 and L4, the two radicals R46 may be the same or different but the two radicals X must be the same, with an amine of formula XLVI HNR42R43 XLVI in which R42 and R43 are as defined above.

The reaction between compounds XXXI and XLVI, respectively, is generally carried out in a solvent, for example, an organic solvent, for example, a lower alcohol, for example, methanol, ethanol or isopropanol, dimethylformamide, tetrahydrofuran or acetonitrile, or in a mixture of two or more of such solvents.

The reaction is generally carried out at a temperature within the range of from 5 to 75"C, especially at room temperature.

The following compounds of formula XXXI are particularly preferred for use as starting materials: (1) RI = R32 = hydrogen, L3 = methylthio and L4 = phenylthio, i.e. S-Methyl,S'-phenyl-N-sulphamoyldi thioimidocarbonate (2) R31 = hydrogen, R32 = methyl, L3 = methylthio and L4 = phenylthio, i.e. S-Methyl,S'-phenyl-N-(N'methyl)-sulphamoyldithioimidocarbonate; (3) R31 = R32 = hydrogen, L3 = L4 = 2-nitrophenyloxy ie Bis-(2-nitrophenyl)-N-sulphamoylimido-carbonate; and (4) R31 = hydrogen, R32 = methyl, L3 = L4 = 2-nitrophenyloxy ie Bis-(2-nitrophenyl)-N-(N'-methyl)-sulpha moylimidocarbonate.

A compound of formula XXXI may be prepared by reacting a compound of formula XXXII

in which Y represents a halogen atom, especailly a chlorine atom, and R31 and R32 are as defined above, with a compound of formula XXXIII or with a compound of formula XXXIV

in which R46 is as defined above.

A compound of formula XXXII may be prepared as described in Chem. Ber. 91, 1339, (1958), in DE-OS 937,645, J. Org. Chem. 41 4028 (1976) or in J. Med. Chem. 15 (5) 538 (1972), and is preferably used when freshly prepared.

A compound of formula XXXIII may be prepared as described in Z. Chem. 8 (12) 459-460 (1968), Bull.

inst. recherches biol unic. Perm, 6, (10), 517-522, or Beilstein E113 page 156, and a compound of formula XXXIV as described in Ann. 287 310, 319 and 321 (1895).

In a compound of formula XXXII I, one radical R46 preferably represents a methyl group and the other preferably represents a phenyl group. In a compound of formula XXXIV, both radicals R46 preferably represent substituted phenyl groups, for example, ortho-nitrophenyl groups.

The reaction between the compound of formula XXXII and the compound of formula XXXIII or XXXIV is preferably carried out in the presence of an organic base, especially a tertiary amino base, for example, triethylamine.

The reaction is preferably carried out in the presence of an aprotic solvent, for example, acetonitrile, or an ether, an aromatic hydrocarbon, a chlorinated aliphatic or aromatic hydrocarbon, for example, diethyi ether, tetrahydrofuran, benzene or dichloromethane.

The reaction is preferably carried out under an inert atmosphere, for example, under nitrogen. The reaction is generally carried out at a temperature within the range of from -50 to +80"C, preferably from -5 to +45"C.

Preferably, a compound of formula XXXII, advantageously freshly prepared, is added dropwise to a solution of the compound of formula XXXIII or XXXIV, and the base is preferably added simultaneously with the compound of formula XXXII. This addition may be carried out over a period of from 5 minutes to 8 hours, preferably from 10 minutes to 2 hours.

Compounds of formula XXXI in which R31 and R32 both represent hydrogen atoms and L3 and L4 both represent alkylthio or both represent alkoxy groups are disclosed in UK Patent Specification No. 1 398 426, which discloses a process for the production of those compounds of formula XXXI in which R31 and R32 both represent hydrogen atoms and L3 and L4 represent lower alkoxy or lower alkylthio groups.

Compounds of formula XXXV are versatile intermediates which can be used in the production of a wide range of sulphamoyl guanidines, sulphamoyl isothioureas, sulphamoyl thioureas, and a variety of heterocyclic systems by displacement of the leaving group L3 by a suitable group.For example, by reacting a compound of formula XLIII

in which L3, R42 and R43 are as defined above and R is as defined above for R42, (R42, R43 and R being the same or different,) with a compound of formula XLV A -(CH1) - X - (CH1) - NH2 XLV in which A represents a phenyl or furyl radical, which radical may be unsubstituted or may have one or more, especially one or two, substituents which may be the same or different, selected from guanidino and mono-alkyl guanidino groups, the alkyl moiety of which has a straight or branched chain and from 1 to 4 carbon atoms, and from groups of formula II

in which Q represents an alkylene group having from 1 to 4 carbon atoms, and R1 and R?, which may be the same or different, each represents a hydrogen atom, or a straight or branched chain alkyl group having from 1 to 4 carbon atoms, or R1 and R2 together with the nitrogen atom to which they are attached form a 4 to 8-membered ring which may contain an oxygen atom or another nitrogen atom, which nitrogen atom may have an alkyl group having from 1 to 4 carbon atoms as substituent, or A represents a thiazolyl or thiadiazolyl radical that is substituted by one or more, especially by one or two, substituents which may be the same or different and which are as defined above for substituents of phenyl and furyl groups A; X represents an oxygen or sulphur atom; n represents 0 or 1; and m represents 2, 3 or 4, there is produced a compound of formula XLI

in which A, X, n, m, R, R42 and R43 are as defined above.

The reaction between compounds XLIII and XLV is generally carried out in a solvent, for example, an organic solvent, for example, a lower alcohol, for example, methanol, ethanol or isopropanol, dimethylformamide, tetrahydrofuran or acetonitrile, or in a mixture of two or more of such solvents. The reaction is generally carried out at a temperature within the range of from 5 to 75"C, especially at room tempera- ture.

Compounds of formula XLI and processes for their production are described and claimed in our copending application no. 8507660 (Case 19). Compounds analogous to compounds XLI may be prepared analogously from other compounds of formula XXXV. An example of the use of a compound of formula XXXV in the production of a heterocyclic system is as follows:: A compound of formula XV

in which R is as defined above, and flio represents an alkoxy, phenoxy, phenylalkoxy, alkylthio, phenylthio or phenylalkylthio group wherein a phenyl or phenalkyl group may be unsubstituted or substituted by one or two substituents, which may be the same or different, selected from alkyl, alkoxy, methylenedioxy, phenoxy, halogen, dimethylaminomethyl, trifluoromethyl, nitro, cyano, sulphonic acid, sulphonamide, amino, mono-alkylamino and di-alkylamino groups, an alkyl moiety having a straight or branched chain and from 1 to 4 carbon atoms, is reacted with a compound of formula XVI R12 - C(OR3)3 XVI in which R3 represents a straight or branched chain alkyl group having from 1 to 4 carbon atoms, and R12 represents a hydrogen atom, an alkyl group having from 1 to 6 carbon atoms, or an -OR3 group, in which R3 is as defined above, to give a compound of formula XVII

in which R, fllO and R12 are as defined above.

A compound of formula XVII may then be reacted with a compound of formula IV E - (CH1), - X - (CH1),, - NH?lV in which E represents a phenyl, imidazolyl, thiazolyl, furyl, thienyl, or pyridyl radical, which radicals may be unsubstituted or may have one or two substituents, selected from straight and branched chain alkyl groups having from 1 to 4 carbon atoms, guanidino and mono-alkyl guanidino groups, the alkyl moiety of which has a straight or branched chain and from 1 to 4 carbon atoms, and groups of the formula II

in which Q represents an alkylene group having from 1 to 4 carbon atoms, and R1 and R2, which may be the same or different, each represents a hydrogen atom, a straight or branched chain alkyl group having from 1 to 4 carbon atoms or, together with the nitrogen atom to which they are attached, Rl and R2 form a 4 to 8-membered ring which may contain an oxygen atom or another nitrogen atom, which nitrogen atom may have an alkyl substituent having from 1 to 4 carbon atoms, X represents -0- or -S n represents 0 or 1; and m represents 2, 3 or 4, to give a compound formula la

in which R and R12 are as defined above, and W represents a group E-(CH2)n - X - (CH1) - NH- in which E, X, n and m are as defined above.

In formula la, alkyl groups may be branched or unbranched, and alkyl groups, for example, alkyl groups R4 and flo, may be unsubstituted or substituted, for example, by one or more, for example, one or two, groups selected from (i) OR6 groups in which RO represents a straight or branched chain alkyl group having from 1 to 6 carbon atoms; (ii) cycloalkyl groups having from 3 to 7 carbon atoms;; (iii) -NR' fla groups in which R7 and R8, which may be the same or different, each represents a hydrogen atom, a straight or branched chain alkyl group having from 1 to 4 carbon atoms, a phenyl group or an acyl group having from 1 to 4 carbon atoms in the alkyl moiety, and R7 and R8 together with the nitrogen atom to which they are attached may form a 5 or 6 membered ring; (iv) -COORs groups in which RO represents a straight or branched chain alkyl group having from 1 to 4 carbon atoms; (v) -CONR7 RO groups in which R7 and R8 are defined above; (vi) alkylsulphonyl groups having from 1 to 4 carbon atoms in the alkyl moiety and phenylsulphonyl groups; (vii) cyano and nitro groups;; (viii) phenyl groups which may be substituted by one or two substituents, which may be the same or different, selected from alkyl, alkoxy, methylenedioxy, phenoxy, halogen, dimethylaminomethyl, trifluoromethyl, nitro, cyano, sulphonic acid, sulphonamide, amino, mono-alkylamino and di-alkylamino groups, an alkyl moiety having a straight or branched chain and from 1 to 4 carbon atoms; (ix) aromatic and non-aromatic heterocyclic groups having from 5 to 8 ring members and one or two hetero-atoms selected from oxygen, sulphur and nitrogen atoms, and optionally having an alkyl substituent having from 1 to 4 carbon atoms on a ring nitrogen atom, for example, a furyl, tetrahydrofuryl, thienly, pyridyl, dihydropyranyl, pyrrolidinyl, N-lower alkyl-pyrrolidinyl, or piperidyl group.

A phenyl group is formula la other than a phenyl group E (which is as defined above), may be unsubstituted or substituted as defined in (viii) above.

Compound XV is cyclised to the thiatriazine XVII by reaction with ortho ester XVI. This reaction may be carried out using an excess of the ortho ester as solvent or, preferably, using an inert solvent, for example, acetonitrile, tetrahydrofuran, dioxane or diglyme, preferably at an elevated temperature, for example, from 80 to 160"C.

Compound IV is generally reacted with compound XVII in a solvent or diluent, preferably in an alcohol, acetone, acetonitrile or DMF. The reaction temperature is, for example, within the range of from 0 - 80"C, depending on the nature of the leaving group flIO Generally when RIO is a substituted phenoxy group, the reaction occurs rapidly at 0 to 20"C, but when R10 is an alkylthio or alkoxy group, elevated reaction temperatures, for example, in the range of from 50 to 100 C, for example, from 60 to 80"C are preferred.

The compound of formula IV is reacted in the form of the free base, as shown. If it is initially present in the form of an acid addition salt, for example, as the hydrochloride or hydrobromide, this is converted into the free base during or, preferably, before reaction with compound XVII. Conversion is carried out with an organic or inorganic base, for example, sodium hydroxide or potassium hydroxide, or a tertiary amine, for example, triethylamine.

Compounds of formula XLI and of formula la have histamine H-2 antagonist activity, and may be used to treat conditions resulting from stimulation by histamine of H-2 receptors, either alone, for example, in inhibiting gastric acid secretion and thugs treating its sequelae, for example, gastric and peptic ulcers; or together with H-1 antagonists, for example, in allergic and certain inflammatory conditions.

Compounds of formula XV and XLIII are particularly preferred compounds of formula XXXV.

The following Examples illustrate the invention, but are not limiting. In the Examples, ratios of eluants are expressed by volume.

EXAMPLE A 1. 3-[2-f(2-Guanidino-4-thiazolyl)methylthio]ethyl]amino-S-meth ylamino-6-meth yI- 1,Z4, 6-thiatriazine- 1,1,- dioxide To 604mg of 2-guanidino-4-[(2-aminoethyl)thiomethyl]-thiazole dihydrochloride was added a solution of 224mg of potassium hydroxide dissolved in 5ml of an hydros ethanol. The resulting suspension was stirred for a few minutes and then filtered to give a clear ethanolic solution of the guanidino-thiazole free base, which was used for the following reactions.

a) To an ethanolic solution of the free base prepared as described above was added 444mg of 3-methylthio-5-methyl- amino-6-methyl-1,2,4,6-thiatriazine-1,1-dioxide dissolved in 10ml of dry acetonitrile. The reaction mixture was heated to reflux for 5 days, after which tic analysis indicated approximately 30% reaction. The reaction solvents were evaporated and the residual oil chromatographed on silica gel, using as eluant chloroform: methanol: concentrated aqueous ammonia (90:10:1). 280mg of unchanged thiatriazine was recovered from this chromatography, followed by 120mg of purified title compound, obtained as a foam after drying in vacuo.

NMR (60MHz) CD1OD 3 = 2.72 (2H, m), 2.92 (3H, d), 3.26 (3H, s), 3.32 (2H, m), 3.70 (2H, s), 6.65 (1H, d) b) To 5ml of an ethanolic solution of 0.Smmole of the guanidinothiazole free base was added 273mg of a crude preparation of 3-methylsul phinyl-5-methylamino-6-methyl-1 ,2,4,6-thiatriazine-1 ,1 -dioxide dissolved in 5ml of dry acetonitrile. After having been stirred at room temperature for 20 minutes, the reaction mixture showed no starting material by tic analysis. The reaction solvents were evaporated off, and the residual oil chromatographed on silica gel as described above to give 112mg of the title compound as a semi-crystalline solid.The hydrochloride salt was formed with anhydrous HCI in ethanol, and recrystallised from ethanol/acetonitrile, m.p. 156-165"C.

MNR (60MHz) DMSO-d6 of free base 3 2.54 (2H, ml, 2.86 (3H, d), 3.15 (3H, s), 3.34 (2H, m), 3.66 (2H, s), 6.68 (1H, d), 7.30 (4H, br.s).

c) To 10ml of an ethanolic solution of 2mmoles of the guanidinothiazole free base prepared as described above was added 200mg of triethylamine followed by 420mg of 3-chloro-5-methylamino-6 methyl-1,2,4,6-thiatriazine-1,1-dioxide dissolved in 5ml of dry acetonitrile. After having been stirred at room temperature for 15 minutes, the reaction mixture showed no starting material by tic analysis. The title compound was obtained as a semi-crystalline solid by the chromatographic procedure described above. Treatment with anhydrous HCI as described above gave the pure HCI salt, which was crystallised from ethanol/acetonitrile: 632mg, m.p. 159-165"C.

NMR (60MHz) DMSO-d6 of HCI salt 8 = 2.54 - 2.66 (2H, m), 2.79 (3H, d), 3.15 (3H, s), 3.25 - 3.42 (2H, m), 3.77 (2H, s), 7.15 (1H, d), 7.60 - 7.86 (2H, m), 8.34 (4H, br.s) 2. 3-[2-[12-Guanidino -4-thiazolyl)methylthio]ethyl]amino-5-tert -butylamino-6-methyl- 1,2,4, 6-thiatriazine 1, 1dioxide To 10ml of an ethanolic solution of 1.Smmole of 2-guanidino-4-[(2-aminoethyl)thiomethyl]thiazole free base prepared as described in Example Al above, was added 380mg of 3-chloro-5-tert.-butylamino-6 methyl-1,2,4,6-thiatriazine-1,1-dioxide dissolved in 5ml of dry acetonitrile.After having been stirred for 2 hours, the reaction mixture was evaporated to dryness and the residue was chromatographed on silica gel using as eluant chloroform/methanol/concentrated aqueous ammonia (90:10:1). 620mg of the title compound was obtained as a foam after drying in vacuo.

NMR (250MHz) DMSO-d6 3 = 1.39 (9H, s), 2.57 (2H, m), 3.19 (3H, d), 3.23 - 3.44 (2H, m), 3.60 (2H, s), 6.48 - 6.55 (1H, m), 6.90 (5H, br.s), 7.61 - 7.76 (1 H, 2xt) 3. 3-[3-[3-r1-PiperidinylmethylJphenoxyApropylamino-5-tert. -butylamino-6-methyl- 1,2,4, 6-thiatriazine- 1,1dioxide 496mg of 3-[3-(1 -piperidinylmethyl)phenoxy]propylamine were dissolved in 10ml of dry acetonitrile.

504mg of 3-chloro-5-tert-butylamino-6-methyl-1,2,4,6-thia- triazine-1,1-dioxide dissolved in 10ml of dry acetonitrile were added dropwise at room temperature to the stirred solution of the amine. After stirring for 1 hour, the solvent was evaporated and the residual oil chromatographed on silica gel using CHCI1/ MeOH/conc. aqueous ammonia (90:10:1). After drying under vacuum, 528mg of the title compound was isolated as a white foam.

NMR (250MHz) DMSO-d6 3 = 1.41 99H, d), 1.46 (6H, m), 1.89 (2H, m), 2.28 (4H, m), 3.18 (3H, d), 3.35 (2H, s), 3.25 (2H, m), 3.97 (2H, m), 6.37 (1h, d), 6.76 - 6.84 (3H, m), 7.12 (1H, t), 7.59 - 7.67 (1H, 2xt) EXAMPLE B 1. 3-Chloro-5-methylamino-6-methyl- 1,2,4,6-thiatriazine- 1, dioxide 666mg of 3-methylthio-5-methylamino-6-methyl-1,2,4,6-thiatriazine-1,1-dioxide were suspended in 20ml of dry methylene dichloride. Chlorine gas was bubbled slowly into the stirred suspension at room temperature until the yellow colour of excess chlorine persisted in the reaction mixture.After having been stirred for 30 minutes, the now clear reaction solution was evaporated to dryness, leaving a white crystalline solid which was recrystallised from acetone/hexane to yield the title compound: 573mg, m.p. 179 1800C.

NMR (60MHz) in CD3CN: 3 = 2.95 (3H,d), 3.30 (3H, s) 2. 3-Chloro-5-tert.-butylamino-6-methyl- 1,2,4, 6-thiatriazine- l, dioxide 400 mg of 3-methylthio-5-tert.-butylamino-6-methyl-1,2,4,6-thiatriazine-1,1-dioxide were reacted with excess chlorine in 1 5ml of dry methylene dichloride as described above for example B1 .319 mg of the title compound were obtained, m.p. 143-145"C.

NMR (60MHz) acetone-d6: 3 = 1.48(9H, s), 3.39 (3H, s) EXAMPLE C 3-Methylsulphinyl-5-methylamino-6-methyl- 1,2,4,6-thiatria-zine- 1,1-dioxide 222mg of 3-methylthio-5-methylamino-6-methyl-1 ,2,4,6-thiatriazine-1 ,1-dioxide were suspended in 5ml of dry chloroform and 410mg of m-chloroperoxybenzoic acid (approx. 80% purity) dissolved in 5ml of methylene dichloride added dropwise to this suspension. A clear solution formed quickly, but after about 30 minutes, a crystalline precipitate began to form. After stirring for 2 hours at room temperature, the thick white precipitate was filtered off and washed thoroughly with ether. After drying, 273mg of crude sulphinylthia-triazine was obtained. This product was sufficiently pure for further reaction.TIc analysis indicated the presence of some m-chlorobenzoic acid.

NMR (60MHz) DMSO-d6: 3 = 2.85 (3H, d), 3.00 (3H, s), 3.30 (3H, s) EXAMPLE 1. 3-Methylthio-5-methylamino-6-methyl- 1,Z4, 6-thiatria- zine- 1,1-dioxide 3.349 of 1-methyl-2-S-benzyl-4-S-methyidi-isothiobiuret hydrobromide was dissolved in 50ml of methylene dichloride containing 1.109 of triethylamine. 1.429 of methylamino-sulphonyl chloride and another 1.10g of triethylamine were added dropwise simultaneously to the stirred solution of di-isothiobiuret.

After having been stirred for 2 hours, the reaction mixture was evaporated to a semi-crystalline solid, which was suspended in 50ml of dry acetonitrile and filtered to remove the crystalline triethylamine hydrochloride. The filtrate was heated to reflux for 1 hour, then evaporated to dryness and the residue chromatographed on silica gel using CHCl1/MeOH (9:1) to yield the title compound, which was crystallised from acetone/hexane, m.p. 189-190"C.

NMR (60MHz) acetone-d6: 3 = 2.42 (3H, s), 3.02 (3H, d), 3.35 (3H,s) Mass spectrum: 222(m/e), 158, 143, 71.

2. 3-Methylthio-5-tert-butylamino-6-methyl- 1,24 6thiatriazine- 1,1-dioxide 1.49 of 1-tert.-butyl-2-S-benzyl-4-S-methyl-di-isothiobiuret hydrobromide was reacted with 0.69 of methylaminosulphonyl chloride as described for Example D1 to give 730mg of the title compound.

NMR (60MHz) acetone, 3 = 1.50 (9H, s), 2.36 (3H, s), 3.30 (3H, s) EXAMPLE 1. 1-Methyl-2-S-benzyl-4-S-methyldi-isothiohiuret h ydrobromide salt.

13.99 of methyl isothiourea sulphate was suspended in 500ml of methylene dichloride. With vigorous stirring, 4.40g of sodium hydroxide dissolved in 50ml of water was added, followed immediately by 7.309 of methyl isothiocya- nate. After having been stirred at room temperature for 2 hours, the reaction mixture was filtered, and the filtrate evaporated to dryness. The residual oil was chromatographed on silica gel with CHCI3/MeOH (9:1) to give 7.70g of l-methyl-4-S-methyldithiobiuret as a colourless oil.

NMR (60MHz) CDCI3: 3 = 2.36 (3H, s), 3.30(3H, d) 3.269 of this oil was refluxed for 1 hour in 50 ml of acetonitrile with 3.429 of benzyl bromide. The solvent was then concentrated to about 10ml and ether added to start crystallisation of the product. This was filtered off, washed with ether and dried to give 3.909 of the title compound, m.p. 151-1520C.

NMR (60MHz) DDMSO-d.i6: 3 = 2.38 (3H, s), 3.04 (3H, s), 4.36 (2H, s), 7.26 (5H, s), 8.70 (2H, br.s) 2. 1- Tert.-butyl-2-S-benzyl-4-S-methyidi-isothiobiuret hydrobromide salt 2.789 of methyl isothiourea sulphate in 50ml of methylene dichloride was reacted with 880mg of sodium hydroxide dissolved in 5ml of water and 3.459 of t-butylisothio- cyanate as described in Example El, except that after having been stirred for 2 hours at room temperature, the reaction mixture was refluxed for 1 hour. Chromatography gave 507mg of 1-tert.-butyl-4-S-methyldithiobiuret, which was then crystallised from hexane, m.p. 132-133"C.

NMR (60MHz) CDCI3: 3 = 1.41 (9H, s), 2.46 (3H, s) Reaction of l-tert.-butyl-4-S-methyldithiobiuret with benzyl bromide as described in Example El gave 830mg of the title compound, m.p. 152-156"C.

NMR (60MHz) DMSO-d6: 3 1.32 (9H, s), 2.33 (3H, s), 4.18 (2H, s), 7.28 (5H, s), 9.28 (2H, br.s) EXAMPLE F 3-[2-J(2-Guanidino-4-thiazolyl)methylthiojethyl]amino-5-methyl-6-methyl- 1,2,4, 6-thiatriazine- 1,1-dioxide 302mg of 2-guanidino-4-[(2-aminoethyl)thiomethyl]thiazole dihydrochloride were treated with 112mg of potassium hydroxide dissolved in 5ml of ethanol as described for Example Al. To the ethanol solution of the guanidinothia-zole free base was added 298mg of 3-(2-nitrophenoxy)-5-methyl-6-methyl-1,2,4,6-thia- triazine-1,1-dioxide dissolved in 10ml of tetrahydrofuran.The reaction mixture was stirred at room temperature for 18 hours, then evaporated to dryness, and the residual oil chromatographed on silica gel with CHCI3/MeOH/conc. aqueous ammonia (90:10:1). The produce was isolated, and crystallised from acetone/ethanol to give 326mg of the title compound, m.p. 171-172"C.

NMR (250MHz) DMSO-d6: 8 = 2.31 (3H, s), 2.58 (2H, t), 3.36 (3H, s), 3.22 - 3.49 (2H, m), 3.60 (2H, s), 6.52 (1H, s), 6.90 (4H, br.s), 8.17 - 8.53 (1H, 2xt) EXAMPLE G 3-(2-Nitrophenoxyl-5-methyl-6-methyl- 1,2,4,6-thiatria-zine- 1,1-dioxide 1.379 of l-(N'methyl)sulphamoyl-2-(2-nitrophenyl)-isourea and 2.429 of trimethyl orthoacetate were refluxed for 3 hours in 10ml of acetonitrile. The solvent was evaporated and the residual solid washed with several portions of ether before recrystallisation from acetone to give the title compound: 810mg, m.p.

212-214"C.

NMR (250MHz) CDCI3: 8 = 2.49 (3H, s), 3.57 (3H, s), 7.35 (1H, d), 7.48 (1H, t), 7.71 (1H, t), 8.17 (1H, d) EXAMPLE H I-l-meth yllsulpham o yl-2-(2-nitrophen yl)-iso urea 3.969 of bis-(2-nitrophenyl)-N-(N'methyl)-sulphamoyl imidocarbonate was suspended in 50 ml of tetrahydrofuran, and 170mg of anhydrous ammonia dissolved in 5ml of tetrahydrofuran was added to the cooled (+5"C), rapidly stirred suspension. The resulting clear solution was allowed to come to ambient temperature over 1 hour, when tic analysis (silica gel, CHCl1/MeOH, 5:1), indicated the absence of starting material.The solvent was evaporated off and the residual solid washed with ether and finaliy recrystallised from acetone/ether to give the title compound: 2.329, m.p. 150-151"C NMR (250MHz) DMSO-d6: 8 = 2.32 (3H, d), 6.67 (1H, m), 7.40 (1H, br.s), 7.51 (2H, m), 7.82 (1H, t), 8.14 (1H, d), 8.81 (1H, br.s) EXAMPLE I Bis-2{2-nitrophenyl)-N-6N'-methyl)sulphamoylimido carbonate 6.06g of bis-(2-nitrophenyl)imido carbonate was dissolved in 150ml of dry methylene dichloride. 2.84g of methylsulphamoyl chloride and 2.20g of triethylamine were added dropwise simultaneously to this solution with rapid stirring.After having been stirred for 15 minutes, the reaction solution was washed twice with water, dried over MgSO4, and evaporated to a crystalline residue which was washed with ether and recrystallised from acetone/ether to give the title compound: 6.50g, m.p. 171-172"C.

NMR (60MHz)DMSO-d0: 8 = 2.50 (3H, d), 7.1 - 8.3 (8H, m) EXAMPLE J 1. 2-Meth yl-3-f2-f(2-guanidin o-4-thiazolyl)m yl)m ethylthioJ-ethylJ-amin o-htert. -b utylamino- 1,2,4, 6-thiatriazine- 1,1-dioxide 302mg of 2-guanidino-4-[(2-aminoethyl)thiomethylithiazole dihydrochloride was suspended in 10ml of ethanol containing 112mg of potassium hydroxide. The suspension was stirred for a few minutes and then filtered to give a clear ethanol solution of the guanidino thiazole free base. To this solution was added 110mg of triethylamine followed by 252 mg of 2-methyl-3-chloro-5-t-butyl-amino-1,2,4,6-thiatria- zine-1,1-dioxide dissolved in 2ml of dry acetonitrile.The reaction solution was stirred for 1 hour at room temperature, then evaporated to dryness, and the residual oil chromatographed on silica gel with CHCl1/ MeOH. The crude product (535mg) was recrystallised twice from ethanol to give the pure title compound: 433mg, m.p. 110-112"C.

NMR (400MHz) DMSO-d6 8 = 1.33 (9H, s), 2.67 (2H, m), 3.14(3H, d), 3.25 - 3.55 (2H, m), 3.64 (2H, s), 6.52 (1 H, d), 6.89 (4H, br.s), 7.04 (1/2H, s), 7.18 (1/2H, s), 7.59 (1/2H, t), 7.84 (1/2H, t).

2. 2-Methyl-3-[3-(3-(1-piperidin4meth4)phenoxy/prnp4]-amino-5-t-butylamino- 1,2,4, 6-thiatriazine- 1,2 dioxide.HC1 salt 143mg of 2-methyl-3-chloro-5-t-butylamino-1,2,4,6-thiatriazine-1,1-dioxide was dissolved in 5ml of dry acetonitrile and added dropwise to a stirred solution of 140mg of 3-[3-(1-piperidinylmethyl)phenoxy)l propylamine in 5ml of dry acetonitrile. After having been stirred at room temperature for 2 hours, the reaction solution was evaporated to dryness and the residual oil was chromatographed on silica gel with CHCl1/MeOH (4:1).The title compound was obtained as a foam after drying in vacuo: 163mg NMR (250 MHz) CDCI3: 3 = 1.41 (9H, s), 1.57 (2H, m), 1.79 (4H, m) 2.13 (2H, m), 2.71 (4H, br.m), 3.37 (3H, d), 3.54 - 3.76 (4H, m) < 4.17 (2H, m), 6.90 (2H, m), 7.27 (2H, m) EXAMPLE K 1. 3-Chloro-S-tert.-butvlamino-6-methyl- 1,2,4, 6-thiatriazine- 1,1-dioxide 1.299 of 3,5-dichloro-6-methyl-12,4,6,-thiatriazine-1, 1-dioxide was dissolved in 70 ml of anhydrous ether (dried over sodium), and to this well stirred solution at room temperature was added dropwise 876mg of tert.-butyl-rie amine in 5ml of ether.After having been stirred for 20 minutes, the reaction mixture was filtered and the filtrate reduced in volume to about 10 ml to start cyrstallisation of the title compound. 575mg of crude product was filtered off and recrystallised from ether to give 493mg of purified material, m.p. 145-147"C.

NMR (250MHz) CDCI3: 3 = 1.52 (9H, s), 3.36 (3H, s) 2. 2-Methyl-3-chloro-5-tert -butylamino- 1,2,4, 6-thiatriazine- 1, 1-dioxide The ether filtrate from the fractional crystallisation of the compound of Example K1 was chromatographed on silica gel with CH?Cl? to give the title compound, which was recrystallised from ether/hexane: 311mg, m.p. 153-154 C.

NMR (250MHz) CDCI3: 3 = 1.44 (9H, s), 3.38 (3H, s).

EXAMPLE 3, 5-Dichloro-6-m ethyl- 1,2,4,6-thiatriazine- 1, 1,-dioxide 2.0g of 3-methylthio-6-methyl-1,2,4,6-thiatriazin-5- one-1,1-dioxide were refluxed for 20 hours in 20ml of POCK, with 8.0g of PCI5. The resulting clear solution was evaporated under vacuum and the residue triturated with dry methylene dichloride. The methylene dichloride extract was filtered through a silica gel column and the product eluted with additional methylene dichloride. The title compound was obtained after recrystallisation from ether/hexane: 1.5g, m.p. 79-80"C.

NMR (60MHz) CDCI3: 3 = 3.70 (3H, s).

Mass Spec. 219 (m+4), 217(m+2), 215(m/e), 180.

EXAMPLE 1. 2-Methyl-3-[2-[(2-guanidino-4-thiazolyl)meth ylthio]-ethyl]-amino-5-dimethylamino- 1,2,4, 6-thiatriazine- 1, 1- dioxide 604mg of 2-guanidino-4-[-aminoethyl)thiomethyl]thiazole dihydrochloride was converted into its free base as described in Example Al. 202mg of triethylamine was added to the ethanol solution followed by 492mg of 2-methyl-3-chloro-5-dimethylamino-1 ,2,4,6-thiatriazine-1, 1-dioxide added dropwise in 10ml of dry acetonitrile. After having been stirred for 30 minutes at room temperature, the reaction solution was evaporated to dryness and the residual oil chromatographed on silica gel with CHCIJ MeOH/conc.

aqueous ammonia (50:10:1). After drying in vacuo the title compound was isolated as a foam; 601mg.

NMR (60MHz) DMSO-d6: 3 = 2.78(2H,t), 3.05 (6H, d), 3.23 (3H, s), 3.65 (2H, t), 3.74 (2H, s), 6.76 (1H, s).

2. 2-Methyl-3-[2-1r2-guanidino-4-thiazolyl)methylthio]-ethyly-amino-5-methoxy- 1,2,4, 6-thiatriazine- 1, 1- dioxide 604mg of 2-guanidino-4[(2-aminoethyl)thiomethyl]thiazole di hydrochloride and 422mg of 2-methyl-3chloro- 5-methoxy-1,2,4,6-thiatriazine-1,1-dioxide were reacted according to the procedure of Example M1 to give the title compound. After chromatography and drying in vacuo, 540mg of the title compound were obtained as a foam.

NMR (250MHz) DMSO-d6: 3 = 2.68 (2H, t), 3.26 (3H, s), 3.32 - 3.55 (2H, m), 3.74 (2H, s), 3.77 (3H, s), 6.96 (1H, s), 7.85 (4H, br. s), 8.59 (1H, t).

3. FMeth yl-3-[2-2-guanidin o-rl-thiazolyllm eth ylthio/-eth yl]-amin o-5-phen y/- 1,2 4, 6-thia triazine- 1, 1-diox- ide 302mg of 2-guanidino-4-[(2-aminoethyl)thio-methylj thiazole dihydrochloride and 257mg of 2-methyl-3chloro-5-phenyl-1,2,4,6-thiatriazine-1,1-dioxide were reacted according to the procedure of Example M1 to give the title compound. After chromatography, the material was recrystallised from ethanol to give 403mg of the title compound, m.p. 139-143"C.

NMR (250MHz) DMSO-d;6: 3 = 2.78 (2H, t), 3.33 (3H, s), 3.68 (2H, s), 3.74 (2H, m), 6.50 (1H, s), 6.92 (4H, br.s) 7.48 - 7.65 (3H, m), 8.17 - 8.21 (2H, d), 8.57 (1H,t) The chlorothiatiazines used in Examples M1, M2 and M3 were prepared by known methods see, for example, DT-OS 2,943,703 and DT-OS 3,134,143.

EXAMPLE N 1. 3-J2-f(2-Guanidino-4-thiazolyl)methylthiojethylj-amino-5-amino-6-methyl- 1,2,4,6-thiatriazine- 1,1-dioxide trifluoroacetic acid salt 300mg of 3-[2-[(2-guanidino-44hiazolyl)methylthioiethyl]-amino-5-teit-butylamino-6-methyl-1 ,2,4,6-thia- triazine-1,1-dioxide was dissolved in 5ml of trifloroacetic acid and heated at reflux for 5 hours. The trifuluoroacetic acid was then evaporated off and the residue recrystallised from ethanol/ether: 236mg, m.p.

110-114C.

NMR (250MHz) DMSO-d6: 3 = 2.54 (2H, t), 3.12 (3H, s), 3.29 (2H, m) 3.77 (2H, s), 7.13 (1H, d), 7.47 (1H, t), 8.41 (4H, br.s).

2. 2-Methyl-3-[2-[r2-guanidino-4-thiazolyl)methylthio]-ethyll-amino-5-amino- 1,2,4,6-thiatriazine- 1, 1-diox- ide trifluoroacetic acid salt 100mg of 2-methyl-3-[2-[(2-guanidino-4-thiazolyl) methylthio]ethyl]-amino-5-tert.-butylamino-1 ,2,4,6- thiatriazine-1,1-dioxide was refluxed in 8m1 of trifluoro- acetic acid for 18 hours. Evaporation of the trifluoro- acetic acid and recrystallisation of the residue from acetone/ether gave the title compound: 84mg.

m.p. 135- 138"C.

NMR (200MHz) DMSO-d6: 3 = 2.65 (2H, t), 3.14 (3H, s), 3.24 -3.46 (2H, m), 3.79 (2H, s), 7.09 (1H, s), 7.76 (1H, t), 8.35 (4H, br.s).

3. 3-[3-[3-{1-Piperidinylmethyl)phenoxylpropyll-amino-5-amino-6-methyl- 1,2,4,6-thiatriazine- 1,1-dioxide trifluoroacetic acid salt 400mg of 3-[3-[3-(1 -piperidinylmethyl)phenoxyipropyl] amino-5-tert.-butylamino-6-methyl-1,2,4,6-thia- triazine -1,1-dioxide was refluxed in 20ml of trifluoroacetic acid for 4 hours. Evaporation and drying under vacuum gave the title compound as a foam: 396mg.

NMR (250MHz) DMSO-d6: 3 = 1.64 - 1.80 (6H, m), 1.93 (2H, t), 2.86 (2H, m), 3.15 (3H, s), 3.17 - 3.34 (4H, m), 4.02 (2H, m), 4.32 (2H, d), 7.05 (2H, m), 7.34 - 7.49 (3H, m), 7.60 (2H, br.s), 9.32 (1H, br.s).

4. 2-Methyl-3-[3-[3-f1-piperidinylmethyl)phenoxyl propyll-amino-5-amino- 1,2,4,6-thiatriazine- 1,1-dioxide trifluoroacetic acid salt 150mg of 2-methyl-3-[3-[3-(1 -piperidinylmethyl) phenoxyj-propyl]-amino-5-tert.-butylamino-1 ,2,4, 6-thiatriazine-1,1-dioxide hydrochloride was refluxed for 18 hours in 10ml of trifluoroacetic acid. The trifluoroacetci acid was then evaporated under vacuum and the residual oil crystallised and recrystallised from ethanol: 120mg, m.p. 189-194"C.

NMR (250MHz) DMSO-d6: 3 = 1.54 - 1.84 (6H, m), 2.01 (2H, t), 2.87 (2H, m), 3.15 (3H, s), 3.28 - 3.49 (4H, m), 4.04 (2H, t), 4.22 (2H, d), 7.02 (2H, br.s), 7.07 (3H, m), 7.38 (1H, t), 7.65 (1H, t), 9.39 (1H, br.s).

EXAMPLE O Bis-methyl-N-sulphamoyldithioimidocarbonate To a solution of 3.759 of dithioimidocarbonate dimethyl ester in 1ODml of dry benzene, 4.35 ul of triethylamine and a solution of 3.589 of freshly prepared sulphamoyl chloride in 40ml of dry benzene were added dropwise simultaneously at 180C, with vigorous stirring under an atmosphere of nitrogen. The addition was carried out over 30 minutes. After a further period of one hour at room temperature, the mixture was evaporated to dryness and triturated with chloroform. The resulting solid was filtered off and dried over silica gel: 3.379 m.p. 148-150"C. m/e 200.

EXAMPLE P Methyl,phenyl-N-sulphamoyl dithioimidocarbonate To a solution of 8.699 of methyl,phenyl-dithioimido- carbonate in 175ml of dry benzene, 8.14ml of triethylamine and a solution of 6.679 of freshly prepared sulphamoyl chloride in 80ml of dry benzene were added dropwise simultaneously at 18"C with vigorous stirring under an atmosphere of nitrogen. The addition was carried out over a period of one hour. External cooling was applied to maintain the temperature of 18"C. After a further 16 hours at room temperature, 100ml of water and 100ml of diethyl ether were added and the mixture was stirred until all the solids had dissolved.The layers were then separated and the organic phase washed with water, dried over MgSO4, and then evaporated to give an oily solid which on trituration with benzene/hexane gave 4.59 of a colourless solid.

Crystallisation from chloroform gave needles, m.p. 125-126"C. m/e 262 1H nmr 60MHz CDCI3 3 : 2.40 (3H, s); 5.35 (2H, s. exch); 7.57 (5H, m).

EXAMPLE O Bis- (2-nitrophen yl)-N-sulphamo ylimidocarbonate To a vigorously stirred solution of 15.0g of bis- (2-nitro-phenyl)-imidocarbonate in a mixture of 200ml of dry benzene, 100ml of ether and 25ml of acetonitrile at 40"C, 7.6ml of triethylamine and a solution of 5.7g of freshly prepared sulphamoyl chloride in 70ml of dry benzene were added dropwise simultaneously over a period of 45 minutes. AFter one hour at room temperature, 100ml of water and 100ml of ethyl acetate were added to dissolve any solids present. The layers were then separated and the aqueous layer extracted with a further 100ml of ethyl acetate.The combined organic layers were washed with water, dried over MgSO4, and then evaporated to give an oily solid, which on trituration with ether gave 6.0g of a pale yellow solid, m.p. 165-167"C.'H nmr 60MHz DMSO-d6 8: 4.35 (2H, hump, exch); 7.1- 8.3 (8H, m).

EXAMPLE R Bis-{2-nitrophenyl)-N-{N'methylJsulphamoylimido carbonate 6.06g of bis-(2-nitrophenyl)imido carbonate was dissolved in 150ml of dry methylene dichloride. 2.849 of methyl- sulphamoyl chloride and 2.209 of triethylamine were added dropwise simultaneously to this solution with rapid stirring. After having been stirred for 15 minutes, the reaction solution was washed twice with water, dried over MgSO4, and evaporated to a crystalline residue which was washed with ether and recrystallised from acetone/ ether to give the title compound: 6.50g, m.p. 171-172"C.

'H nmr 60MHz DMSO-d6: 2.50 (3H, d), 7.1 - 8.3 (8H, m).

Claims

1. A compound of formula I

in which formula R represents a hydrogen atom, a straight or branched chain alkyl group having from 1 to 4 carbon atoms, a phenyl group or a phenalkyl group, the alkyl moiety of which has a straight or branched chain and from 1 to 4 carbon atoms, an alkyl, phenyl or phenalkyl group being unsubstituted or substituted by one or more substituents, which may be the same or different, for example, by one or two substituents, especially by one substituent, selected from halogen atoms, straight and branched chain alkyl groups having from 1 to 4 carbon atoms, straight and branched chain alkoxy groups having from 1 to 4 carbon atoms, nitro and trifluoromethyl groups;; Wand Z, which may be the same or different, each represents a group E-(CH2)n - X - (CH2m - NH- in which E represents a phenyl, imidazolyl, thiazolyl, furyl, thienyl, or pyridyl radical, which radicals may be unsubstituted or may have one or two substituents, selected from straight and branched chain alkyl groups having from 1 to 4 carbon atoms, guanidino and mono-alkyl guanidino groups, the alkyl moiety of which has a straight or branched chain and from 1 to 4 carbon atoms, and groups of the formula II

in which Q represents an alkylene group having from 1 to 4 carbon atoms, and R' and R2, which may be the same or different each represents a hydrogen atom, a straight or branched chain alkyl group having from 1 to 4 carbon atoms or, together with the nitrogen atom to which they are attached, Rl and R2 form a 4 to 8-membered ring which may contain an oxygen atom or another nitrogen atom, which nitrogen atom may have an alkyl substituent having from 1 to 4 carbon atoms, or one of W and Z represents a group E - (Ch2)n - X - (CH2)m - NH- as defined above, and the other represents a hydrogen atom; a straight or branched chain alkyl group having from 1 to 6 carbon atoms; a phenyl group; an -OR3 group in which R3 represents a straight or branched chain alkyl group having from 1 to 4 carbon atoms; or an NR4RS group in which R4 and R5, which may be the same or different, each represents a hydrogen atom, an unsubstituted or substituted straight or branched chain alkyl group having from 1 to 6 carbon atoms, or a phenyl group; X rGpesents -O- or-S-; n represents 0 or 1; and m represents 2, 3 or 4, and in which an alkyl group may have a straight or branched chain, and in which an alkyl group, for example, alkyl groups R4 and R5, may be unsubstituted or substituted, by one or more groups selected from (i) OR6 groups in which RO represents a straight or branched chain alkyl group having from 1 to 6 carbon atoms; (ii) cycloalkyl groups having from 3 to 7 carbon atoms; (iii) -NR7 flo groups in which R7 and R8, which may be the same or different, each represents a hydrogen atom, a straight or branched chain alkyl group having from 1 to 4 carbon atoms, a phenyl group or an acyl group having from 1 to 4 carbon atoms in the alkyl moiety, and R7 and R8 together with the nitrogen atom to which they are attached may form a 5 or 6 membered ring;; (iv) -COORs groups in which Rg represents a straight or branched chain alkyl group having from 1 to 4 carbon atoms; (v) -CONR7 flo groups in which R7 and R6 are defined above; (vi) alkylsulphonyl groups having from 1 to 4 carbon atoms in the alkyl moiety and phenylsulphonyl groups; (vii) cyano and nitro groups; (viii) phenyl groups which may be substituted by one or two substituents, which may be the same or different, selected from alkyl, alkoxy, methylenedioxy, phenoxy, halogen, dimethylaminomethyl, trifluoromethyl, nitro, cyano, sulphonic acid, sulphonamide, amino, mono-alkylamino and di-alkylamino groups, an alkyl moiety having a straight or branched chain and from 1 to 4 carbon atoms;; (ix) aromatic and non-aromatic heterocyclic groups having from 5 to 8 ring members and one or two hetero-atoms selected from oxygen, sulphur and nitrogen atoms, and optionally having an alkyl substituent having from 1 to 4 carbon atoms on a ring nitrogen atom, for example, a furyl, tetrahydrofuryl, thienyl, pyridyl, dihydropyranyl, pyrrolidinyl, N-lower alkyl-pyrrolidinyl, or piperidyl group, and in which a phenyl group other than a phenyl group E (which is as defined above), may be unsubstituted or substituted as defined in (viii) above; and salts of a compound of formula I.

2. A compound as claimed in claim 1, wherein E represents a 2-guanidino-4-thiazolyl group or a 3-(1piperidinylmethyl)phenyl group.

3. A compound as claimed in claim 2, wherein when E represents a 2-guanidino-4-thiazolyl group, n is 1,Xis-S-,andmis2.

4. A compound as claimed in claim 2, wherein when E represents a 3-(1-piperidinylmethyl)phenyl group, n is 0, X is -0-, and m is 3.

5. A compound as claimed in any one of claims 2 to 4, wherein W or Z represents an NR4RSgroup, a methoxy group or a phenyl group.

6. R = methyl Z = methylamino, W = E-(CH2)n - X -(CH2)m - NH- in which E= [2-[(2-Guanidino-4- - thiazolyl), n = 1, X = S, and m = 2 i.e. 3-[2-[(2-Guanidino-44hiazolyl)methylthio]ethyli-amino-5-methy- lamino-6-methyl-1 ,2,4,6-thiatriazine-1 ,1 - dioxide.

7. R = methyl, Z = tert. -butylamino, W = E-(CH2)n - X -(CH2)m - NH- in which E = [2-[(2- Guanidino-4thiazolyl), n = 1, X = S, and m = 2 i.e. [2[(2-Guanidino-4-thiazolyl)methylthiojethylj-amino-5-tert.-buty- lamino-6-methyl-1 ,2,4,6-thiatriazine-1 1 - dioxide.

8. R = methyl, Z = tert.-butylamino, W = E(CH2)n ~X-(cH2)m - NH- in which E = [3-[3-[1-Piperidinyl- .

methyl-phenyl), n = O, X = 0, and m = 3 i.e. 3-[3-[3-(1#peridinylmethyl)phenoxy]propyl]-amino- 5-tert. butylamino-6-methyl-1 ,2,4,6-thiatriazine-1 ,1 - dioxide.

9. R = methyl, W = tert.butylamino, Z = E-(CH2) 5-tert.-butylamino-1,2,4,6-thintriazine-1, 1-dioxide and the hydrochloride salt thereof.

10. R = methyl, W = dimethylamino, Z = E-(cH2)n ~ X ~(cH2)m - NH- in which E = [2-[(2- Guanidino4-thiazolyl), n = 1, X = S, and m = 2 i.e. 2-Methyl-3-[2-[(2-guanidino-4-thiazolyl)methylthioj- ethyl]-amino- 5-dimethylamino-1 ,2,4,6-thiatriazine-1 1 - dioxide.

11. R = methyl, W = methoxy, A = E-(cH2)n - X -(CH,),- NH- in which E = [2[(2-Guanidino-4- thiazolyl), n = 1, X = S, and m = 2 i.e. 2-Methyl-3-[2-[(2-guanidino-4-thiazolyl)methylthio]- ethyl]-amino-5-methoxy-1,2,4,6-thiatriazine-1,1-dioxide.

12. R = methyl, W = phenyl, Z = E-(cH2)n - X -(CH1) - NH- in which E = [2[(2-Guanidino-4- thiazolyl), n = 1, X = S, and m = 2 i.e. 2-Methyl-3-[2-((2-guanidino-4-thiazolyl)methylthio]- ethyl]-amino-5-phenyl 1,2,4,6-thiatriazine-1,1-dioxide.

13. R = methyl, Z =amino, W = E-(CH1) - X -(CH1) - NH- in which E = [2-[(2-Guanidino-4- thiazolyl), n = 1, X = S, and m = 2 i.e. 3-[2-[(2-Guanidino-4-thiazolyl)methylthio]ethyl]-amino-5-amino-6-methyl 1,2,4,6-thiatriazine-1,1- dioxide, and the trifluoroacetic acid salt thereof.

14. R = methyl, W = amino, Z = E-(CH1) - X -(CH1) - NH- in which E = [2-[(2-Guanidino-4- thiazolyl), n = 1, X = S, and m = 2 i.e. 2-Methyl-3-[2-[(2-guanidino-4-thiazolyl)methylthioj- ethyl]-amino-5-amino 1,2,4,6-thiatriazine-1,1-dioxide.

15. R = methyl, Z = amino, W = E-(CH1),, - X -(CH,),- NH- in which E = [3-[3-(1-Piperidinyl- methylphenyl), n = 0, X = 0, and m = 3 i.e. 3-[3-[3-(1-Piperidinylmethyl)phenoxyjpropylj-amino- 5-amino-6 methyl-l ,2,4,6-thiatriazine-1 ,l-dioxide, and its trifluoroacetic acid salt.

16. R = methyl, W = amino, Z = E-(cH2)n - X - (CH2) - NH- in which E = [3-[3-(1-Piperidinyl- methylphenyl), n = 0, X = 0, and m = 3 i.e. 2-Methyl-3-[3-[3-(1 -piperidinylmethyl)phenoxy]-propyl] amino-5 1 ,2,4,6-thiatriazine-1 ,1 -dioxide, and its trifluoroacetic acid salt.

17. A process for the production of a compound of formula I as claimed in claim 1, which comprises reacting a 1,2,4,6-thiatriazine of formula IIIA or IIIB

in which L represents a halogen atom, an alkoxy, phenoxy or phenylalkoxy group, an alkylthio, phenylthio or phenylalkylthio group, an alkylsulphinyl, phenylsulphinyl or phenylalkylsulphinyl group, or an alkylsulphonyl, phenylsulphonyl or phenylalkylsulphonyl group, in which groups an alkyl group or alkyl moiety has from 1 to 4 carbon atoms, and a phenyl group may be substituted as defined in claim 1, and R, Wand Z are as defined in claim 1, with a compound of the general formula IV E-(CH2)n-X-(CH2) m-NH2 IV in which E, X, m and n are as defined for formula I.

18. A process as claimed in claim 17, wherein when Z in compound IIIA or IIIB represents a group N R4R5 in which R4 represents a protecting group that can be removed by hydrogenolysis or by acid or base catalysed hydrolysis, this group is removed from the resulting compound of formula I by hydrogenolysis or by acid or base catalysed hydrolysis to provide a compound of formula I in which W or Z is a group NHR5 or -NH2.

19. A process as claimed in claim 17 or claim 18, wherein a compound of formula IIIA in which R is as defined in claim 1, Z represents a group NHR4 in which R4 is as defined in claim 1 and L represents a group R10 which represents an alkoxy, phenoxy or phenylalkoxy group, an alkylthio, phenylthio or phenylalkylthio group, is produced by cyclising a compound of the general formula XI

in which R, R4 and R'0 are as defined above, and R" represents an alkyl or phenalkyl group, by heating.

20. A process as claimed claim 19, wherein a compound of formula Xl is produced by reacting a com pound of the general formula IX

in which R4, R10 and R" are as defined in claim 19, with a compound of formula X CISO2NHR X in which R is as defined in claim 1, in the presence of a tertiary base.

21. A process as claimed in claim 20, wherein a compound of formula IX is produced by reacting a compound of formula VII

in which R4 and Rio are as defined in claim 19, with an alkylating agent which comprises the group fl" as defined in claim 19.

22. A process as claimed in claim 21, wherein the alkylating agent has the formula VIII RI-Y Vlli in which R1l is as defined in claim 19 and Y represents a halogen atom.

23. A process as claimed in claim 21 or claim 22, wherein a compound of formula VII is produced by reacting a compound of formula V with a compound of formula VI

in which formulae R4 and Rio are as defined in claim 19.

24. A process as claimed in claim 17, wherein a compound of formula IIIA in which L represents a group flio as defined in claim 19 and Z represents a group R12 which represents a hydrogen atom, an alkyl group havng up to 6 carbon atoms, a phenyl group or a group -OR3 in which R3 represents a lower alkyl group, is produced by reacting a compound of formula XV

in which R is as defined in claim 17 and flio is as defined in claim 19, with a compound of formula XVI R12 - C - (OR3)3 in which R12 and R3 are as defined above.

25. A process as claimed in claim 24, wherein a compound of formula XV is produced by reacting a compound of formula XIV

in which R and R10 are as defined in claim 19, with anhydrous ammonia.

26. A process as claimed in claim 25, wherein a compound of formula XIV is produced by reacting a compound of formula XIII

in which flio is as deinfed in claim 19, with a compound of formula X CISO2NHR X in which R is as defined in claim 1.

27. A process as claimed in any one of claims 19 to 26, wherein a resulting compound of formula IIIZ in which Z represents a group Rio which represets an alkylthio, phenylthio or phenylalkylthio group is converted into a compound of formula IIIA in which Z represents an alkylsulphinyl, alkylsulphonyl, phenylsulphinyl, phenylsulphonyl, phenylalkylsulphinyl or phenylalkylsulphonyl group by oxidation of the thio group, for example, using a peracid, hydrogen peroxide, or a periodate, perborate or permanganate salt.

28. A process as claimed in any one of claims 19 to 26, wherein a resulting compound of formula 1IIA in which Z represents a group flio which represents an alkylthio or phenylthio group is reacted with an excess of a halogen to give a compound of formula IllZ in which Z represents a halogen atom.

29. A process as claimed in claim 17, wherein a compound of formula IIIA in which L represents a halogen atom and Z represents a group -NR4 R5 and/or a compound of formula IIIB in which L represents a halogen atom and W represents a group -NR4 R5is produced by reacting a compound of formula XXII

in which R is as defined in claim 1, with a compound of formula HNR4RO XXIII in which R4 and R5 are as defined in claim 1.

30. A process as claimed in claim 29, wherein compound XXII is reacted with the amine XXIII at a temperature within the range of from 0 to 20"C to give a mixture of compounds IIIA and 1118.

31. A process as claimed in claim 30, wherein compound XXII is reacted with the amine XXIII at a temperature within the range of from -40 to -20 "C to give predominantly a compound of formula IIIB.

32. A process as claimed in any one of claims 29 to 31, wherein a compound of formula XXII is produced by reacting a compound of formula XXI

in which R13 represents an alkyl, phenyl or phenalkyl group, with excess phosphorus pentachloride.

33. A process as claimed in claim 17, carried out substantially as described in any one of Examples Al, A2, A3, F, J1, J2, M1, M2 and M3 herein.

34. A process as claimed in claim 18, carried out substantially as described in any one of Examples N1, N2, N3 and N4 herein.

35. A process as claimed in claim 19, carried out substantilly as described in Example D1 or D2 herein.

36. A process as claimed in claim 20, carried out substantially as described in Example D1 or D2 herein.

37. A process as claimed in claim 21, carried out substantially as described in Example El or E2 herein.

38. A process as claimed in claim 23, carried out substantially as described in Example El or E2 herein.

39. A process as claimed in claim 24, carried out substantially as described in Example G herein.

40. A process as claimed in claim 25, carried out substantially as described in Example H herein.

41. A process as claimed in claim 26, carried out substantially as described in any one of Examples I, O, P, 0 and R herein.

42. A process as claimed in claim 27, carried out substantially as described in Example C herein.

43. A process as claimed in claim 28, carried out substantially as described in Example B1 or 82 herein.

44. A process as claimed in claim 29, carried out substantially as described in Example K herein.

45. A process as claimed in claim 32, carried out substantially as described in Example L herein.

46. A compound as claimed in claim 1, whenever produced by a process as claimed in any one of claims 16 to 45.

47. A compound as claimed in claim 1, substantially as described in any one of Examples Al, A2, A3, F, J1, J2, M1, M2 and M3 herein.

48. A pharmaceutical preparation which comprises a compound of the general formula I as claimed in any one of claims 1 to 16, claim 46 or claim 47, or a physiologically tolerable salt thereof, in admixture or conjunction with a pharmaceutically suitable carrier.

49. A compound of the general formula I as claimed in any one of claims 1 to 16, claim 46 or claim 47, or a physiologically tolerable salt thereof, for use in the manufacture of a medicament for the treatment of conditions resulting from stimulation of by histamine of histamine H-2 receptors.

50. A compound of formula XXXV

in which RI and R32, which may be the same or different, each represents a hydrogen atom, a straight or branched chain alkyl group having from 1 to 4 carbon atoms, a cycloalkyl group having from 3 to 7 carbon atoms, a phenyl group, or a phenlkyl group having from 1 to 4 carbon atoms in the alkyl moiety, wherein an alkyl, cycloalkyl, phenyl or phenalkyl group may be unsubstituted or substituted by one or more substituents, which may be the same or different, for example, by one or two substituents, especially by one substituent, selected from halogen atoms, straight or branched chain alkyl groups having from 1 to 4 carbon atoms, straight or branched chain alkoxy groups having from 1 to 4 carbon atoms, and nitro and trifluoromethyl groups; or R3' and R32 together with the nitrogen atom to which they are attached, form a 4- to 7-membered ring which may contain one or more further hetero-atoms, for example, selected from nitrogen, oxygen and sulphur atoms; L3 represents a group -XR46 in which X represents an oxygen or sulphur atom and flio represents a straight or branched chain alkyl group having from 1 to 4 carbon atoms, an unsubstituted or substituted phenyl group, or an unsubstituted or substituted phenalkyl group having from 1 to 4 carbon atoms in the alkyl moiety, wherein a phenyl or phenalkyl group may be substituted by one or two substituents selected from alkyl, alkyoxy, methylenedioxy, phenoxy, halogen, dialkylaminoalkyl (especially dimethylaminomethyl), trifluoromethyl, nitro, cyano, sulphonic acid, sulphonamide, amino, and mono- and dialkylamino groups, an alkyl moiety having a straight or branched chain and from 1 to 4 carbon atoms, and R42 and R43, which may be the same or different, each represents a hydrogen atom, a straight or branched chain alkyl group having from 1 to 4 carbon atoms, a phenyl group of a phenylkyl group, the alkyl moiety of which has a straight or branched chain and from 1 to 4 carbon atoms, wherein an alkyl, phenyl or phenyalkyl group may be unsubstituted or substituted by one or more substitutents, which may be the same or different, for example, by one or two substituents, especially by one substituent, selected from halogen atoms, straight and branched chain alkyl groups having from 1 to 4 carbon atoms, straight and branched chain alkoxy groups having from 1 to 4 carbon atoms, nitro and trifluoromethyl groups.

51. A compound as claimed in claim 50, wherein R42 and R43 both represent hydrogen atoms, or one represents a hydrogen atom and the other represents a methyl group.

52. A compound as claimed in claim 50 or claim 51, wherein R3l represents a hydrogen atom, and R32 represents a hydrogen atom or a straight or branched chain alkyl group having from 1 to 6 carbon atoms, especially a methyl or ethyl group.

53. A compound as claimed in any one of claims 50 to 52, wherein L3 represents a lower alkylthio group, especially a methylthio group, or represents a phenoxy group, especially a substituted phenoxy group.

54. A compound as claimed in claim 50, having the formula XV

in which R represents a hydrogen atom, a straight or branched chain alkyl group having from 1 to 4 carbon atoms, a phenyl group or a phenalkyl group, the alkyl moiety of which has a straight or branched chain and from 1 to 4 carbon atoms, an alkyl, phenyl or phenalkyl group being unsubstituted or substituted by one or more substituents, which may be the same or different, for example, by one or two substitutents, especially by one substituent, selected from halogen atoms, straight and branched chain alkyl groups having from 1 to 4 carbon atoms, straight and branched chain alkoxy groups having from 1 to 4 carbon atoms, nitro and trifluoromethyl groups; and RIO represents an alkoxy, alkylthio, phenoxy, phenylthio, phenylalkoxy or phenylalkylthio group.

55. A compound as claimed in claim 3, having the formula XLIII

in which L3 is as defined in claim 50, and R, R42 and R43 are as defined for R in claim 54, R, R42 and R43 being the same or different.

56. A process for the production of a compound of formula XXXV as claimed in claim 50, which comprises reacting a compound of formula XXXI

in which R3q, R32 and L3 are as defined in claim 50, and L4 is as defined for L3, L3 and L4 being the same or different, with a compound of formula HNR42R43 XXXVI in which R42 and R42 are as defined in claim 50.

57. A process as claimed in claim 56, carried out substantially as described in Example H herein.

58. A compound as claimed in claim 50, whenever produced by a process as claimed in claim 56 or claim 57.

59. A compound as claimed in claim 50, substantially as described in Example H herein.

60. A compound as claimed in any one of claims 50, 58 and 59, for use in the production of sulpamoyl guanidines, sulphamoyl isothioureas, sulphamoylthioureas, and heterocyclic systems.

61. A compound of formula IIIA

in which L, Z and Rare as defined in claim 1, Z having any of the meanings given in claim 1.

62. A compound as claimed in claim 61, having the formula XII

in which R and R4 are as defined in claim 1 and R10 is as defined in claim 19.

63. A compound as claimed in claim 61, having the formula XVII

in which R is as defined in claim 1, R10 is as defined in claim 19 and R12 is as defined in claim 24.

64. A compound as claimed in claim 61, having the formula XVIII

in which R and R4 are as defined in claim 1 and R13 is as defined in claim 32.

65. A compound as claimed in ciaim 61, having the formula XIX

in which R and R4 are as defined in claim 1, R13 is as defined in claim 32, and x is 1 or 2.

66. A compound as claimed in claim 61, having the formula XX

in which R and R4 are as defined in claim 1 and Y' is as defined in claim 22.

67. A compound as claimed in claim 61, having the formula XXIV

in which R, R4 and R5 are as defined in claim 1.

68. A compound having the formula XXV

in which R, R4 and R5 are as defined in claim 1.

69. A compound having the formula XXII

in which R is as defined in claim 1.