Synthesis, characterization and antibacterial study of 7-O-substituted derivatives of chlorinated Coumarin

In this research work, a series of 7-O-alkyl/aralkyl/acyl substituted derivatives of chlorinated coumarin was synthesized and screened for their antibacterial activity. The parent compound 6-chloro-7-hydroxy-4-methyl-2H- chromen-2-one (3) was prepared by the coupling of homogeneous mixing of 4-chlororesorcinol (1) and ethylacetoacetate (2) in a conc. H₂SO ₄ medium. Further, the 7-O-substituted derivatives of coumarins 5a-i and 7a-h were prepared by the reaction of parent compound with different alkyl/aralkyl/acyl halides 4a-i and 6a-h. The synthesized compounds were supported via spectral data. The prepared compounds were evaluated for inhibition activity against bacterial strains including Gram-positive and Gram-negative and were observed that some of the compounds exhibited activity to varying degree.