Synthesis and Antioxidant Ability of Some New 6-amino-7H- [1,2,4]triazolo[3,4-b][1,3,4]thiadiazin-3-yl) Derivatives Bearing 2,6-Dimethoxy-4-(methoxymethyl)Phenol Moiety

Compound 4-(((6-amino-7H-[1,2,4]triazolo[3,4-b][1,3,4]thiadiazin-3-yl)methoxy) methyl)-2,6-dimethoxyphenol (6) was synthesized by multi steps. The corresponding acetonitrile thioalkyl (7) was cyclized by refluxing with acetic acid to afford 4-(((6-amino-7H-[1,2,4]triazolo[3,4-b][1,3,4]thiadiazin-3-yl)methoxy)methyl)-2,6-dimethoxy phenol (8). Two new series of 4-(((6-(3-(4-aryl)thioureido)-7H-[1,2,4]triazolo [3,4-b][1,3,4] thiadiazin-3-yl)methoxy)methyl)-2,6-dimethoxyphenol (9a-c) and of 4-(((6-(substitutedbenzamido)7H-[1,2,4]triazolo[3,4-b][1,3,4]thiadiazin-3-yl)methoxy) methyl)-2,6-dimethoxyphenol (10a-c) were synthesized as new derivatives for fused 1,2,4-trizaole- thiadiazine (8). The antioxidants of newly compounds were evaluated by DPPH and FRAP assays. Compound 9b showed significant antioxidant ability in both assays (higher than ascorbic acid) as well compound 6, 8 and 10a-c showed antioxidant higher than BHT.