40% aq. HF Catalyzed Three-Component Synthesis of Novel Indeno[1, 2-b][1,8]naphthyridin-6(11H)-one Derivatives and their Antimicrobial Activity

A three-component synthesis of novel 5-phenyl-2-(thiophen-2-yl)-4-(trifluoromethyl)-5Hindeno [1,2-b] [1,8] naphthyridin-6(11H)-one derivatives (4a-n) was prepared using 6-phenyl/ (thiophen- 2-yl)-4-(trifluoromethyl)pyridin-2-amine, 1H-indene-1,3(2H)-dione, and aryl aldehyde using 40% aq. HF with good yield. All the synthesized compounds were screened against Gram-positive and Gram-negative bacterial strains and different Candida strains by the well diffusion method. Compounds 4c, 4f, and 4g showed promising activity on Bacillus subtilis strain and compounds 4c and 4g showed promising activity towards Candida albicans strains.