Abstract

SYNTHESIS AND ANTI-MICROBIAL ACTIVITY OF NOVEL COUMARINS CONTAINING SUNSTITUTED-1,3,4-OXADIAZOLE DERIVATIVES

S. Srinivas, B. Srinivas, P. Kavitha, S. Kavitha and M. Ravinder*

Abstract

An efficient general method has been described for the synthesis of novel 4-methyl-7-(5-sunstituted-1,3,4-oxadiazol-2-yl)methoxy)-2Hchromen- 2-ones derivatives 5(a-h). Compound 7-hydroxy-4-methyl coumarin treated with α-bromo ethylacetate in the presence of potassium carbonate in acetone as solvent to give compound ethyl-2- (4-methyl-2-oxo-2H-chrome-7-yloxy)acetate (2), followed by treated with hydrazine hydrate to form corresponding 2-(4-methyl-2-oxo-2Hchromen- 7-yloxy)aceto hydrazide (3). The compound 3 is condensed with substituted aromatic aldehydes than followed by cyclization with glacial acetic acid to yield the title compounds 5(a-h). These analogs were evaluated for their antimicrobial activity against Staphylococcus aureus (Gram positive bacteria) Escherichia Coli (Gram Negative bacteria) and Aspergillus niger, Candida albicans (fungi) The analogs 5e, identified as potent activity and 5f, 5g showed moderate activity against antimicrobial agents. Structural elucidation of all the newly synthesized title compounds has been established by the spectroscopic data IR, 1HNMR, mass and elemental analysis.

Keywords: 7-hydroxy-4-methyl coumarin, 1,3,4-oxadiazole, antibacterial strains, antifungal strains.