Synthesis and properties of 4-substituted-1-piperazinyl-propyl derivatives of 1-phenyl-7-methylpyrimido-[4,5-d]pyrimidin-4-one.

In reactions of 1-phenyl-7-methyl-4-oxo-2-thioxo-1,2,3,4-tetrahydropyrimido[ 4,5-d]pyrimidin e (1) with 1-(3-chloropropyl)-4-methyl(phenyl, 3-chlorophenyl, 2-pyrimidynyl, 2-thiazolyl)piperazines (5), mixtures of isomeric N- and S-substituted derivatives of compound 1 (3 and 4) were obtained. Isomers were separated by fractional crystallization. The structure of novel compounds 3 and 4 was confirmed by elemental and spectral analyses. In pharmacological screening compounds 3b and 4b displayed rather strong analgesic action, inhibited amphetamine hyperactivity and abolished apomorphine stereotypy. Compounds 3e,3d and 4e attenuated m-chlorophenylpiperazine-induced hypothermia.

Synthesis and properties of new derivatives of ethyl 7-methyl-2,4-dioxo-1,2,3,4-tetrahydropyrido [2,3-d]pyrimidine-5-carboxylate.

Condensation of diethyl 2-amino-6-methylpyridine-3,4-dicarboxylate with phenyl or cyclohexyl isocyanates gave the corresponding derivatives of ethyl 7-methyl-2,4-dioxo-1,2,3,4-tetrahydropyrido [2,3-d]pyrimidine- 5-carboxylate[(V), (VI)]. Alkylation of (V) and (VI) afforded the corresponding N-1 substituted derivatives (XI-XIX).

Synthesis and properties of the derivatives of 2-alkylthio-4-oxo-3,4- (and -1,4)-dihydropyrido-[2,3-d]pyrimidine-5- and -6-carboxylic acids.

Condensation of diethyl 2-amino-6-methylpyridine-3,4-dicarboxylate (I) with the corresponding isothiocyanates afforded derivatives of ethyl 4-oxo-2-thioxo-1,2,3,4-tetrahydropyrido [2,3-d]pyrimidine-5-carboxylate (V-VII). Alkylation of (V), (VI) and (XI) gave the corresponding derivatives of ethyl 2-alkylthio-4-oxo-3,4-(and 1,4)-dihydropyrido[2,3-d]pyrimidine-5- and -6- carboxylate [(XII-XVI), (XX-XXII)]. Some of the obtained compounds were active pharmacologically.

Syntheses and properties of selected derivatives of pyrimido[5,4-e]-1,3-thiazine and pyrimido[4,5-d]pyrimidine.

In the reactions of ethyl 4-chloro/tosyloxy/-2-methylpyrimidine-5-carboxylate with differently substituted thioureas, new derivatives of 2,3-dihydro-7-methylpyrimido-[5,4-e]-1,3-thiazine (5-9) and of 7-methyl-1,2,3,4-tetrahydropyrimido[4,5-d]pyrimidine (12, 13) were obtained. Besides, some derivatives of 4-phenylamino-2-methylpyrimidine-5-carboxylic acid (15-20) were also synthesized. Structure of the compounds was confirmed by spectral analysis (IR, H-NMR) and chemical transformations. In the screening pharmacological examinations some of the compounds revealed analgesic, antiinflammatory and immunosuppressive activity.

Synthesis and properties of amides of 1-benzyl-3-methyl- and 1-butyl-3-phenyl-7-methyl-4-oxo-2-thioxo (2,4-dioxo)-1,2,3,4-tetrahydropyrido-[2,3-d]pyrimidine-6-carboxy lic acids.

Amides of 1-benzyl-3,7-dimethyl-4-oxo-2-thioxo-1,2,3,4- tetrahydropyrido[2,3]pyrimidine-6-carboxylic acid were obtained by the condensation of ammonia, primary and secondary cyclic amines with the corresponding acid chloride. As by - products amides of 1-benzyl-3,7-dimethyl-2,4-dioxo-1,2,3,4-tetrahydropyrido[2,3-d]pyr imidine-6- carboxylic acid were isolated as a result of desulfuration. The same reaction performed with chloride of 1-butyl-7-methyl-3-phenyl-4-oxo-2-thioxo-1,2,3,4-tetrahydropyri do[2,3- d]pyrimidine-6-carboxylic acid gave mainly the corresponding 2,4-dioxo-amides.

Synthesis and properties of new 3-acyl- and 3-carbamoyl derivatives of esters of 3H-2-imino-7-methyl-4-oxopyrido[3,2-e]-1,3-thiazine-5- and -6-carboxylic acids.

It was stated that esters of 3H-2-imino-7-methyl-4-oxopyrido[3,2-e]-1,3-thiazine-5- and -6-carboxylic acids react with acyl anhydrides and chlorides giving 3-acyl derivatives. Reaction of the above mentioned esters with isocyanates affords the corresponding 3-carbamoyl derivatives.

A novel system: 2H-pyrido[3,2-e]-1,2-thiazine-1,1-dioxide. Synthesis and properties of some derivatives.

A rearrangement of 2H-2-acetonyl(phenacyl)-4,6-dimethyl- pyrido[3,2-d]isothiazoline-3-one-1,1-dioxides (I), (II) to derivatives of the unknown system of 2H-pyrido[3,2-e]-1,2-thiazine-1,1-dioxide (V), (XIII) is described; the synthesis of 2-N-substituted derivatives (VI - XII), (XIV - XVI) is also given. The structures of the new compounds were confirmed with elemental analyses and spectral data (I.R., N.M.R., MS). Some of the newly obtained compounds showed strong analgesic activity upon pharmacological screening.

Synthesis and properties of some derivatives of 2H-4,6-dimethylpyrido[3,2-d]isothiazolin-3-one-1,1-dioxide.

The synthesis of 2H-4,6-dimethylpyrido[3,2-d]isothiazolin-3-one-1,1-dioxide and its 2-N-substituted derivatives are described. Structures of the obtained compounds were determined on the basis of elemental analyses and spectral data I.R., N.M.R., MS. Preliminary information on the pharmacological properties of the obtained compounds also given.

Synthesis and properties of 3-aminomethyl derivatives of 3H-2-imino-7-methyl-4-oxopyrido-[3,2-e]-1,3-thiazine-5- and -6-carboxylic acids.

It was stated that esters of 3H-2-imino-7-methyl-4-oxopyrido [3,2-e]-1,3-thiazine-5- and -6-carboxylic acids (I, II) undergo the Mannich reaction giving the corresponding 3-aminomethyl derivatives (III-XIV). Derivatives of ester II [(XII) and (XIV)] showed distinct analgesic and antiserotonic activities.

Investigations on the synthesis and properties of new derivatives of pyrido[3,2-e]-1,3-thiazino[3,2-a]-s-triazine.

It has been found that the condensation of esters of 3H-2-imino-7-methyl-4-oxopyrido[3,2-e]-1,3-thiazine-5- and -6-carboxylic acids (I, II) with formaldehyde and primary amines affords the corresponding derivatives of a new heterocyclic system pyrido[3,2-e]-1,3-thiazino [3,2-a]-s-triazine (IX-XXIV).

Investigations on the synthesis and properties of new derivatives of ethyl 3H-2-imino-7-methyl-4-oxopyrido [3,2-e]-1,3-thiazine-6-carboxylate and isomeric compounds.

Condensation of diethyl 2-chloro-6-methylpyridine-3,5-dicarboxylate (IV) with thiourea and alkyl or alkenyl N-mono- and N,N'-disubstituted thioureas gives mainly the corresponding derivatives of ethyl 3H-2-imino-7-methyl-4-oxopyrido [3,2-e]-1,3-thiazine-6-carboxylate (VI-XII). As by-products isomeric derivatives of ethyl 7-methyl-4-oxo-2-thioxo-1,2,3,4-tetrahydropyrido [2,3-d) pyrimidine-6-carboxylate (XIII-XVIII) are formed.

Investigations on the synthesis and properties of new derivatives of methyl 3H-2-imino-7-methyl-4-oxopyrido [3,2-e]-1,3-thiazine-5-carboxylate.

Condensation of dimethyl 2-chloro-6-methylpyridine-3,4-dicarboxylate with thiourea and its N-substituted derivatives is described. It has been found that depending on the kind of substituents in the starting thiourea derivatives, pyrido [3,2-e]-1,3-thiazine or pyrido [2,3-d] pyrimidine derivatives were formed.

Synthesis of derivatives of beta-aminomethyl-gamma-(p-chlorophenyl)-gamma-hydroxybutyric acid.

Several new derivatives of beta-aminomethyl-gamma-(p-chlorophenyl)-gamma-hydroxybutyric acids have been obtained. The substrates, beta-aminomethyl derivatives of gamma-(p-chlorophenyl)-tetrahydrofuranone-2 1-4, were converted by the reactions of ammonolysis, aminolysis and hydrazinolysis into appropriate amides and hydrazides of beta-aminomethyl-gamma-(p-chlorophenyl)-gamma-hydroxybutyric acid. Compounds 10, 11, 16, 18, 19 and 20 show depressant activity on CNS, while compounds 6 and 8 demonstrate antiinflammatory action.

Synthesis of D,L beta-aminomethyl derivatives of gamma-(p-chlorophenyl)-tetrahydrofuran-2-one.

Several new D,L beta-aminomethyl derivatives of gamma-(p-chlorophenyl)-tetrahydrofuran-2-one have been synthesized. The derivatives of D,L beta-aminomethyl-beta-(p-chlorobenzoyl)-propionic acid 2-6 were used as the substrates. These compounds were obtained by the Mannich reaction from acid 1, cyclic secondary amines and formaldehyde. After the reduction with NaBH4, and cyclization, derivatives 2-6 were converted into the appropriate derivatives of tetrahydrofuran-2-one 9-13. Some of the obtained compounds (5, 6, 8, 11 and 12) showed depressant activity against the central nervous system.

Studies on derivatives of 2-amino-4-p-chlorophenylthiazole-5-acetic acid. IV. Addition reactions of thioglycolic acid to 2-N-aralkylidene derivatives of 2-amino-4-p-chlorophenylthiazole-5-acetic acid.

In the course of studies on compounds with expected antiinflammatory and immunosuppressive activity a series of new derivatives of 2-amino-4-p-chlorophenylthiazole-5-acetic acid have been synthesized. Several new and unexpected details of the chemical properties of these compounds were revealed. The chemical structure of the new compounds was confirmed by degradation and identification of the decomposition products and by spectral analysis.

Studies on derivatives of 2-amino-4-p-chlorophenylthiazole-5-acetic acid. V. Syntheses of 2-N-aralkylidene and 2-N-aralkyl derivatives of 2-amino-4-p-chlorophenylthiazole-5-acetic acid.

A number of new N-aralkylidene and N-aralkyl derivatives of amides and hydrazides of 2-amino-4-p-chlorophenylthiazole-5-acetic acid (III-XXIX) have been synthesized. These compounds were obtained in two various ways depending on the character of substituents in the carboxyl group. The chemical structure of the newly obtained compounds was determined on the basis of the data of elementary and spectral analyses.

Studies on derivatives of 2-amino-4-p-chlorophenylthiazole-5-acetic acid. VI. Syntheses and properties of 2-N-aralkyl-alpha-sulphoderivatives of tert-amides of 2-amino-4-p-chlorophenylthiazole-5-acetic acid.

In the course of the studies on compounds with expected antiinflammatory and immunosuppressive activity several new tert-amides derivatives of 2-N-aralkylamino-alpha-sulpho-2-amino-4-p-chlorophenylthiazole-5-acetic acid were synthesized. Some of the previously described Schiff bases reacted with aqueous alcoholic solution of sodium bisulphite and as a result several (III-VIII) alpha-sulphoderivatives were obtained. The course of the reactions was studied and the structure of the new compounds was confirmed.