Synthesis, antimicrobial and cytotoxic activity of novel azetidine-2-one derivatives of 1H-benzimidazole

摘要

A series of l-methyI-N-[(substituted-phenylrnethylidene)-lH-benzimidazol-2-amines (4a-4g) were prepared via the formation of 1-methylH-benzimidazol-2-amine (3), which was prepared by the cycloaddition of o-phenylenediamine (1) with cyanogen bromide in the presence of aqueous base followed by N-methylation with methyl iodide in the presence of anhydrous potassium carbonate in dry acetonitrile. Moreover, the four-membered β-lactam ring was introduced by the cycloaddition of 4a-4g and chloroacetyl chloride in the presence of triethylamine catalyst to give 3-chIoro-i-(l-methyl-lH-benzimidazol-2-yl)-(4'-substituted)-phenylazetidin-2-one 5a-5g. A total of 14 compounds were synthesized and characterized by IR, 'H NMR, ~(13)C NMR and Mass spectral technique, in addition they were evaluated for anti-bacterial and cytotoxic properties. Among the chemicals tested 4a, 4b, 5a, 5b, 5g exhibited good antibacterial activity and 5f, 5g shown good cytotoxic activity in vitro.