SYNTHESIS OF NEW HETEROCYCLIC COMPOUNDS CONTAINING 1,3,4-THIADIAZOLE MOIETY AND THEIR ANTIBACTERIAL AND ANTIFUNGAL ACTIVITIES

A new compounds of 2-mercapto-5-phenyl-4,6-dione-1,3,5-tiazino[6,5-b][1,3,4] thiadiazole (2), 2-[2- p-methoxyphenyl-4-oxo-1,3-thiazolidin-3-yl]-5-mercapto-1,3,4-thiadiazole (4), 1-[2-(2-amino-1,3,4- thiadiazol-5-ylthio)acetyl] -2,4,5-trihydropyridazin-3,6-dione (7) and 1-[2-(2-amino-1,3,4- thiadiazole-5 -ylthio) acetyl]-3-methylpyrazol-5-one (8) were synthesized in good yield via condensation of 2- amino-5-mercapto-1,3,4-thiadiazole (1) with different organic reagents. All new compounds were tested against three strains of Gram negative bacteria (Escherichia coli, Klebsiella pneumoniae and Proteus vulgaris) and two strains of fungi (Candida albicans and Aspergillus niger), comparing these activities with that of the starting material. Compounds (2), (4), and (7) were highly active against all bacteria strains. Compound (1) was highly active against Candida albicans than others while none of the tested compounds were active against Aspergillus niger.