Synthesis and antimicrobial screening of 5-benzylidine-2-imino-3-(2-oxo-2H-benzopyran-6-yl)-thiazolidin-4-one and its derivatives

Abstract

2-imino-3-(2-oxo-2H-benzopyran-6-yl)-thiazolidin-4-one 4a-c have been synthesized from 6-amino-coumarin as starting material. Condensation of iminothiazolidinone with different substituted aromatic aldehydes occurred at reactive methylene group present at C-5 position of thiazolidin-4-one ring and resulted in the formation of 5-arylidene-2-imino-3-(2-oxo-2H-benzopyran-6-yl)-thiazolidin-4-one 5a-i. The formation of 2-imino-3-(2-oxo-2H-benzopyran-6-yl)-thiazolidin-4-one 4c was confirmed by hydrolysis with 2% HCl to give 3-(2-oxo-2H-benzopyran-6-yl)-thiazolidine-2,4-dione 6c. The structures of the compounds 2a-c, 4a-c, 5a-i and 6c have been established on the basis of spectral and analytical data. The compounds 5a-i has been screened for their antimicrobial activity and has been found to exhibit significant antibacterial activities.