Synthesis and antimicrobial activity of benzimidazolyl oxazolyl thiazolidin-4-ones and azetidin-2-ones

Abstract

A new series of 3-[4-(1<em>H</em>-benzo[<em>d</em>] imidazol-2-yl) oxazol-2-yl]-2-thiazolidin -4-ones <strong>4</strong> and 1-[4-(1<em>H</em>-benzo[<em>d</em>] imidazol-2-yl) oxazol-2-yl)-3-azetidin-2-ones <strong>5</strong> have been prepared from 2-acetyl benzimidazole <strong>1</strong>. Compound <strong>1</strong> on treatment with urea in presence of I₂ furnishes 4-(1<em>H</em>-benzo[<em>d</em>] imidazol-2-yl) oxazol-2-amine <strong>2</strong>, which on condensation with aromatic aldehydes affords the corresponding Schiff bases <strong>3</strong>. Cyclocondensation of <strong>3</strong> with thioglycollic acid produces the benzimidazolyl oxazolyl thiazolidin-4-ones <strong>4</strong>, whereas, reaction of <strong>3</strong> with chloroacetyl chloride in presence of triethyl amine furnishes benzimidazolyl oxazolyl azetidin-2-ones <strong>5</strong>. The structures of the newly synthesized compounds <strong>3-5</strong> have been elucidated on the basis of spectral (IR, ¹H and ¹³C NMR and MS) and analytical data. The title compounds <strong>4</strong> and <strong>5</strong> have been screened for their antimicrobial activity. Some of the compounds exhibit promising antimicrobial activity.