Abstract

A series of seven novel azetedinones 4a-g have been synthesized by cyclocondensation of various Schiff bases of phenothiazine with chloroacetyl chloride in presence of triethylamine. Various Schiff bases of phenothiazine were synthesized by condensation of 2-hydrazinyl-1-(10H-phenothiazin-10-yl)ethanone 2 with various aryl aldehydes. Compound 2 was synthesized by reacting 2-chloro-1-(10H-phenothiazin-10-yl) ethanone 1 with hydrazine hydrate. The synthesized compounds were characterized by IR, ¹H-NMR and mass spectra. The titled compounds were evaluated for anti-tubercular, anti-bacterial, anti-fungal and anti-inflammatory activity by Lowenstein-Jensen medium method, cup plate method, disc diffusion method and carrageenan induced paw edema method, respectively. All the seven compounds 4a-g at a concentration of 100, 10 and 1 mg/L showed inhibition against the growth of Mycobacterium tuberculosis. Compounds showed good anti-bacterial activity against Staphylococcus aureus and Bacillus subtilis. Compound 4e showed equipotent antibacterial activity with streptomycin standard and showed better anti-bacterial activity against gram positive bacteria profile than gram negative bacteria. Zone of inhibition was not found for the compounds against Escherichia coli and Pseudomonas aeruginosa. Compounds 4a-g exhibited good antifungal activity against Aspergillus species and no activity against Candida albicans. None of the reported compounds showed promising anti-inflammatory activity.

Key words: Azetidinones, anti-tubercular, anti-bacterial, anti-fungal, inflammation