Abstract
A new series of N-butyl-2-(quinolin-8-yloxy)acetamide (2a-e) and N-butyl-2-(5-((quinolin-8-yloxy)methyl)-1,3,4-oxadiazol-2-ylthio)acetamide(5a-e) were synthesized and characterized by FTIR, 1H NMR, 13C NMR and LC-MS. The antioxidant properties by DPPH, hydroxyl radical scavenging activity and superoxide radical scavenging activities against standard ascorbic acid, mannitol and butylated hydroxyl anisole were evaluated respectively. Further angiotensin converting enzyme inhibition activity (ACE-I) inhibition of the newly synthesized compounds (2a-e) and (5a-e) were described. From the results obtained it was revealed that the compounds 2e, 5a and 5e possess better antioxidant property and the compound 2d as active ACE-I inhibitor against standard lisnopril. Docking simulation further supported the probable binding conformation of ACE-I active site by N-butyl-2-(quinolin-8-yloxy)acetamide derivatives 2a-e. From the antioxidant screening it was explored that the compounds having electron donating groups like -CH3 and a parent compound showed good in vitro biological activity than those compounds having electron withdrawing groups like -Cl which showed moderate activity. The compound having both –Cl and –CH3 showed good in-vitro ACE-I inhibitor activity. Analysis of the docking study gave details on the fine relationship linking structure and activity, and also offer clues for structural modifications would improve the activity.
