DESIGN, SYNTHESIS OF SOME NOVEL 1,3,4-THIADIAZOLE DERIVATIVES ASSOCIATED WITH PYRIMIDINE CORE UNIT BY USING THIOUREA REAGENT

A new series of 1,3,4-Thiadiazole derivatives associated with pyrimidine core unit (7a-j) were synthesized from 4-phenylpyrimidine-2-carboxylic acid (4) with different aromatic/Heterocyclic carboxylic hydrazides (5 a-j) in the presence of POCl3. Finally these 1,3,4-oxadiazole derivatives are converted into 1,3,4-thiadiazoles by using thiourea. The chemical structures of these compounds were confirmed by various physico-chemical methods viz. IR, H-1-NMR, EI-Mass, C-13-NMR analysis. Newly synthesized compounds were screened in vitro for their anti-microbial activity against varieties of gram-positive and gram-negative bacterial strains and fungi strains. The compounds 7j, 7i and 7e shows highly significant antimicrobial activity as compared to the standard drug.