AN EFFICIENT SYNTHESIS OF SOME NOVEL BIOACTIVE AZETIDINONE DERIVATIVES INCLUDING 5-(BENZOFURAN-2-YL) AND 1-PHENYL-1H-PYRAZOLE-3-CARBOXAMIDE MOIETY

In continuation of our efforts in the development of novel drugs, in the present article we have described synthesis of a series of novel azetidinones derivatives (4a-i) containing 5-(benzofuran-2-yl) and 1-phenyl-1H-pyrazole-3-carboxamide moiety, with excellent yields and without formation of undesirable side products from cyclo condensation reaction of N’- (benzylidene) -5- (benzofuran- 2- yl) -1 -phenyl -1H -pyrazole- 3-carbohydrazide derivatives (3a-i) with chloro acetyl chloride in the presence of triethylamine in DMF. Carbohydrazones of aryl aldehydes (3a-i) used as the starting compound was obtained by one-pot condensation of 5-(benzofuran-2-yl)-1-phenyl-1H-pyrazole-3-carbohydrazide (1) with various substituted aromatic aldehydes (2a-i) and a catalytic amount of acetic acid in ethanol. The structures of newly synthesized compounds have been established through elemental analysis and spectral studies like IR, ¹H NMR, ¹³C-NMR and Mass spectra. All the synthesized compounds were screened for their in-vitro antibacterial activity against different strains of microbes such as S. aureus, E. coli, P. vulgaris and S. typhi at different concentration. The result of the bioactivity confirmed that most of the newly synthesized compounds showed the significant activity when compared with the standard drug Chloramphenicol which might be due to the cyclic carbonyl group present in azetidinones.