SYNTHESIS OF SOME NOVEL THIOPHENE AND THIAZOLE DERIVATIVES AND THEIR ANTIMICROBIAL EVALUATION

Reactions of phenyl isothiocyanate with several active methylene compounds 1 (3-oxo-3-phenylpropanenitrile, ethyl 2-cyanoacetate, pentane-2,4-dione and ethyl acetoacetate) and a molar equivalent of potassium hydroxide in dimethylformamide afforded potassium 1-(phenylamino)ethenethiolates as intermediates 2. Reactions of 2 and 2-bromo-1-(5-methyl-1-(4-tolyl)-1H-1,2,3-triazol-4-yl)ethanone (3) afforded novel thiazole and thiophene derivatives 4, 12, 13 and 23a,b in 68-78% yields. The structures of the synthesized products were confirmed using various spectroscopic techniques and single X-ray crystal structures. The novel thiophenes and thiazoles showed good antimicrobial activities against the tested bacteria and fungi.