Synthesis and anti-inflammatory activity of some novel 1,3,4-oxadiazole derivatives.

Some novel 1,3,4-oxadiazoline and 1,3,4-oxadiazole derivatives have been synthesized from 3-hydroxy-5,6-diphenyl-1,2,4-triazine. Illucidation of the structures of the isolated products has been proved in the light of their elemental analysis, spectroscopic data and unambiguous synthesis in certain cases. Some derivatives have shown promising anti-inflammatory activity in comparison to phenylbutazone.

Synthesis and antiinflammatory properties of some novel thiazolidinones and imidazolidinones derived from 4-(3-phenyl-4(3H)-quinazolinon-2-yl)-3-thiosemicarbazone.

A series of quinazolinone thiazolidinone and imidazolidinone derivatives were prepared. These compounds were evaluated for their antiinflammatory activity. The most active compounds (6b, 6c and 6d) were found to be superior to phenylbutazone as they were devoid of any ulcerogenic activity.

Synthesis and antifungal activity of some imidazo, pyrazino and v-triazoloquinoxalines.

The reaction of 6,7-diamino-1,4-diethyl-11-quinoxaline-1 H,4H-2,3-dione (1) with aliphatic and aromatic carboxylic acids in the presence and absence of an acid catalyst affords 2-alkyl- and 2-aryl-5,8-diethyl-imidazo[4,5-g]quinoxaline-5 H,8 H-6,7-diones 2a-1. Cyclization of 1 with carbon disulphide in basic medium yields 2-mercapto-5,8-diethyl-imidazo[4,5-g]-quinoxaline-5 H,8 H-6,7-dione (4) which on reactions with methyl iodide and substituted benzyl halides give the S-substituted derivatives 5a-f. Condensation of 1 with 1,2-diketones yields the corresponding pyrazinoquinoxalines 6a-e. v-Triazoloquinoxaline 7 is obtained by cyclization of 1 with nitrous acid. Compounds 2a-1, 5a-f and 6a-3 exhibit moderate to weak antifungal activity.

Synthesis and antihypertensive activity of novel 1-(4-benzyl-1-phthalazinyl)-pyrazolo[3,4-d]pyrimidines.

Convenient Syntheses of derivatives of the pyrazolo[3,4-d]pyrimidines from 1-(4-benzyl-1-phthalazinyl)-3-amino-4-cyano-5-methylpyrazole (1) and carbon disulphide, aryl isothiocyanates, nitriles or guanidine are described. Derivatives of compound 1 undergo cyclization to the titled ring system by action of dimethylformamide dimethylacetal or hydrogen sulphide followed by treatment with triethylamine. Some of the new compounds were studied as antihypertensive agents.

Synthesis and antiinflammatory activity of novel pyrimidine derivatives.

Hydrazinolysis of ethyl [(4-methyl-6-phenylpyrimidin-2-yl)oxy]acetate (1) gives the unexpected bis(4-methyl-6-phenylpyrimidin-2-yl)hydrazine (2). The desired [(4 methyl-6-phenylpyrimidin-2-yl)oxy]acetohydrazide (3) was prepared from the ester (1) with hydrazine in absolute ethanol. Starting from 3, several new hydrazones, 1,3,4 oxadiazoles, 1,3,4-thiadiazoles, 1,2,4-triazoles and 1,3-thiazoles have been synthesized. Structure of the new compounds was confirmed by elemental analysis, spectral data and alternative synthesis in certain cases. Some representative examples were evaluated for their antiinflammatory activities.

Synthesis and anticonvulsant properties of some novel quinazolone-thiosemicarbazone and 4-thiazolidone derivatives.

Diverse biological activities have been found in compounds having a quinazolinone ring system. A large number of 4(3H)-quinazolinones, in particular those possessing 2-alkyl-3-aryl, 2,3-dialkyl, and 2-alkyl-3-amino substitution, have been evaluated for pharmacological activity. On the other hand, thiazolidone derivatives are reported to have anesthetic, anticonvulsant, and hypnotic activity.