Studies on Thiazole/ Oxazole Derivatives Incorporating Quinazoline Moiety as Potent Free Radical Scavenging and Anti‐Inflammatory Agents

ABSTRACT A number of Biologically active non‐steroid heterocyclic compounds N‐(4‐substituted benzylidene)‐2‐(2‐aminooxazol‐4‐yl)‐6‐methylquinazolin‐3(4H)‐amine (3a‐3e) , N‐(4‐substituted benzylidene)‐2‐(2‐aminothiozol‐4‐yl)‐6‐methylquinazolin‐3(4H)‐amine (3a’‐3e’), (E)‐N'‐(2‐(2‐aminooxazol‐4‐yl)‐6‐methylquinazolin‐3(4H)‐yl)‐N‐(4‐substituted phenylimino) ‐4‐substituted benzamidine (4a‐4h) and (E)‐N'‐(2‐(2‐aminothiozol‐4‐yl)‐6‐methylquinazolin‐3(4H)‐yl)‐N‐(4‐substituted phenylimino)‐4‐substituted benzamidine (4a’‐4h’) were synthesized by the condensation starting from 6‐methylquinazolin‐3(4H)‐amine and 4‐substituted benzaldehyde. By using spectroscopic methods including IR, 1HNMR, 13CNMR, and GCMS, as well as elemental analysis, it has been possible to confirm the structural configuration of recently synthesized compounds. These substances were examined for their analgesic, ulcerogenic, free radical scavenging, anti‐inflammatory, and acute toxicity properties, and their actions were contrasted with those of conventional medications. Compounds 4c’ and 4e’ were more potentially active than other compounds and standard drugs. The IC 50 value at 25, 50, and 100 mg/kg p.o. concentration was found to be 58.4043 and 38.92 against inflammation and analgesic activity for compound 4c’ and 44.70 for 4e, against the Antioxidant measure.