Synthesis and Antimicrobial Activity of New Isoxazolyl Benzo[1,4] diazepine-5-one Derivatives

A series of novel isoxazolyl-1,4-benzodiazepine-5-ones 4 have been synthesized by the reaction of phenacyl isoxazolylamines 1 with o-nitrobenzoic acids 2 to furnish different (E)-N-(3-methyl-5-styrylisoxazol-4-yl)-2-nitro-N-(2-oxo-2-phenylethyl)benzamides 3, which on treatment with Fe-AcOH underwent reductive cyclization to afford the target compounds 4a-w. The newly synthesized compounds were characterized by IR, (HNMR)-H-1, (CNMR)-C-13, and HRMS analysis. The target compounds 4a-w were evaluated for their invitro antimicrobial activity. Among the synthesized compounds, compounds 4r, 4s, 4t, 4u, 4v and 4w showed potent antimicrobial activity as compared with the reference drugs. Most of the newly synthesized title compounds have shown good to excellent antimicrobial activity.