Department of Chemistry, Faculty of Science, Assiut University, Assiut, Egypt Manuscript received 16 October 1981, accepted 12 November 1982 2-(N-Arylcarboxamidomethyl thio)-benzoxazoles (3), -benzthiazoles (4) and -benzimidazoles (5) have been synthesised by the reaction of 2a, 2b and 2c with different amines in presence of EEDQ as condensing agent. The structures were elucidated via another route of preparation. Cyclisation of 5 in pyridine and acetic anhydride furnished 2-N-aryl aminothiazolo 13, 2-a] benzimidazoies (6). Oxidation of (3b, k, f and 1) with hydrogen peroxide gave the corresponding sulphones (7a-d), respectively. The biological activity of some compounds were screened against some bacteria and fungi.