Anti-oxidant and anti-bacterial activities of novel N'-arylmethylidene-2-(3, 4-dimethyl-5, 5-dioxidopyrazolo[4,3-c][1,2]benzothiazin-2(4H)-yl) acetohydrazides.

A series of potential anti-oxidant and anti-bacterial N'-arylmethylidene-2-(3,4-dimethyl-5,5-dioxidopyrazolo[4,3-c][1,2]benzothiazin-2(4H)-yl)acetohydrazides was synthesized in a facile way starting from commercially available saccharine. 3,4-Dimethyl-2,4-dihydropyrazolo[4,3-c][1,2]benzothiazine 5,5-dioxide was obtained by ring expansion of 2-(2-oxopropyl)-1,2-benzisothiazol-3(2H)-one 1,1-dioxide followed by N-methylation and cyclization with hydrazine using ultrasonic irradiation. N-alkylation of the cyclized product with methyl chloroacetate followed by its reaction with hydrazine and subsequent ultrasonic mediated condensations with aromatic aldehydes afforded the title compounds. All the synthesized compounds were subjected to the preliminary evaluation for their anti-oxidant and anti-bacterial activities. Copyright 2009 Elsevier Masson SAS. All rights reserved.