Novel 3,6‐Disubstituted 7 H ‐1,2,4‐Triazolo[3,4‐ b ][1,3,4]thiadiazines: Synthesis, Characterization, and Evaluation of Analgesic / Anti‐inflammatory, Antioxidant Activities

In this study, the synthesis of a new series of 3,6‐disubstituted‐7 H ‐1,2,4‐triazolo[3,4‐ b ][1,3,4]thiadiazine 1a – 4c compounds derived from 4‐amino‐3‐substituted‐1,2,4‐triazole‐5‐thiones 1 – 4 is described. All of the synthesized compounds were screened for their possible analgesic / anti‐inflammatory, antioxidant activities and gastric toxicity. The compound 2c was found to have both significant analgesic and consistent anti‐inflammatory activity without inducing any gastric lesions along with minimal lipid peroxidation. A deep insight into the structures of the active compounds revealed that the compounds carrying an electron withdrawing group (a chloride or fluoride) on the phenyl ring at 6‐position of the condensed heterocyclic derivatives exhibited noticeable higher activity.