Synthesis of some novel cyanopyridines and isoxazoles bearing sulphonamide moiety and their antimicrobial activity

Substituted 2-propen-1-ones 2a-h, prepared by the reaction of p-(2,5-dichlorobenzenesulphonamido)acetophenone 1 with araldehydes, on condensation with malononitrile in the presence of ammonium accetate yield cyanopyridines 3a-h. Also 2a-h on reaction with hydroxylamine hydrochloride in the presence of sodium acetate in acetic acid afford isoxazoles 4a-h. The structures of 3a-h and 4a-h have been established on the basis of elemental analyses and spectral (IR, H-1 NMR and mass) data. The products have been screened for their antimicrobial activity against various strains of bacteria and fungi.