SYNTHESIS AND EVALUATION OF 4-NITRO CHALCONES: EXPLORING ANTIBACTERIAL ACTIVITY

Abstract

Chalcone or (E)-1,3-diphenyl-2-propene-1-one is reported to be a precursor of flavonoids and isoflavonoids and are the open-chain intermediates in aurones synthesis of flavones. With a benzylideneacetophenone scaffold and a three-carbon α, β unsaturated carbonyl bridge connecting the two aromatic nuclei, they can be found in numerous conjugated forms in nature. The aim of this research is to synthesize and characterize some 4-nitro-containing substituted chalcones. The molecules were screened for antibacterial activities against B. subtilis and K. pneumonia. All the substituted nitro-chalcones (1-4) showed low to moderate antibacterial activity against B. subtilis and K. pneumonia. The compounds demonstrated ZOI values of 1.5 mm to 3.5 mm for B. subtilis and 2.5 mm to 3.5 mm for K. pneumonia at 0.1% level whereas ZOI values of 2.5 mm to 3.5 mm for B. subtilis and 4.9 mm to 7.2 mm for K. pneumonia at 0.2% level. Compound 1 containing dimethylamino demonstrated the best antibacterial activity; however far low activity than the standard drug ciprofloxacin.