SYNTHESIS AND BIOLOGICAL EVALUATION OF SOME NEW COUMARIN DERIVATIVES AS ANTIMICROBIAL AGENTS

Abstract

A series of new 7-[2-(3-alkyl/aryl-4-arylthiazol-2(3H)-ylidene)hydrazono)propoxy]-4-methyl-2H-chromen-2-ones, (6-9a-e), was prepared by the reaction of appropriate N-alkyl/aryl-2-[1-(4-methyl-2-oxo-2H-chromen-7yloxy)propan-2-ylidene]hydrazine carbothioamides (4a-d)and phenacyl bromides (5a-e). The purity of all new compounds was checked by TLC andelucidation of their structures was confirmed by IR, 1H NMR, and mass spectrometry along withelemental microanalyses. All the target compounds were evaluated for their possibleantimicrobial activity. Most of the tested compounds showed weak to moderate antibacterialactivity against most of the bacterial strains used in comparison with gatifloxacin as a referencedrug. The most active compounds were 6b, 6c, 7b, 8b, 8c, and 9c against B. cereus, E. coli andS. marcescens. Results of antifungal activity revealed that all compounds showed weak tomoderate activity against S. brevicaulis, while ketoconazole as a reference drug was completelyinactive. Compounds 6a, 6b, 6c, 6e and 7b were even more active than ketoconazole against F.oxysporum.