SOLID SiO2-H3PO4 IS AN EFFICIENT CATALYST FOR CYCLIZATION OF ENONES UNDER SOLVENT-FREE CONDITION: SYNTHESIS AND ANTIMICROBIAL ACTIVITIES OF SOME OXAZINE DERIVATIVES

摘要

A series of some 1, 3-oxazine amine derivatives including 4-(1-naphthyl)-5,6-dihydro-6-(substituted phenyl)-oxazine-2-amines has been synthesised by solid SiO2-H3PO4 catalyzed solvent-free cyclization of aryl chalcones and urea under microwave irradiation. The yields of the oxazines were more than 80%. The synthesised oxazine amines were characterized by their physical constants, analytical and spectroscopic data. The antimicrobial activities of these oxazine derivatives have been studied using Bauer-Kirby method.