Synthesis, Characterization, Stereochemistry and Antimicrobial Evaluation of N-Acyltetrahydrobenzodiazepin-2-ones

Abstract

A few N5-substituted (1) and N1,N5-disubstituted tetrahydro-1,5-benzodiazepin-2-ones (2-8) viz. N5-chloroacetyl-, N5-formyl-, N5-dichloro-acetyl-, N1,N5-diethoxycarbonyl-, N1,N5-bischloroacetyl-, N5-piperazinoacetyl- and N5-morpholinoacetyltetrahydro-1,5-benzodiazepin-2-ones have been synthesized. The characterization and conformational analysis of these compounds 2-8 have been carried out using IR and 1H, 13C, DEPT & 2D (COSY & HSQC) NMR spectral techniques. The coupling constants for compounds 3-6 were determined by irradiating the C4-methyl doublet. The appearance of major and minor conformers has been found in the case of benzodiazepin-2-ones (3 and 6) and the spectral data confirm the equilibrium due to ring inversion over the N-C=O rotation. The spectral data and the extracted coupling constant values revealed that the substituted tetrahydro-1,5-benzodiazepin-2-ones (2-8) prefer to adopt boat conformation. The antimicrobial activity of compounds 1-8 has also been evaluated.