Synthesis of 1,2-dihydropyridine, Arylidene, Hydrazide, and Terthienylnicotinamidine Hydrochloride Analogs: Theoretical Studies, and Antioxidant Activity Assessment

Abstract

Background: In the current work, we have utilized the reactivity of N-(4-acetylphenyl)-2-(4-formylphenoxy)acetamide for the synthesis of novel series of 1,2-dihydropyridines, arylidines, and hydrazides. Our strategies were prolonged for the synthesis of novel terthienylnicotinamidine hydrochloride salt through a Stille coupling reaction of 6-(5'-bromo-[2,2'-bithiophen]-5-yl)nicotinonitrile with 2-tributyltin thiophene followed by treatment with lithium trimethylsilylamide and subsequent hydrolysis. Method: Method: The newly prepared structures were well-elucidated by analytical and spectral data (IR, 1H-NMR, 13C-NMR, MS, and elemental analysis). The theoretical studies of terthienylnicotinamidine verified that the other atoms that carry a high density of positive values are considered active centers for the electron acceptor. Result: The novel synthesized compounds were efficiently established by spectroscopic data and elemental analysis. The antioxidant activity of the synthesized arylidene, hydrazide, and dihydropyridine compounds was assessed by ABTS•+ free radical assay. Conclusion: The results verified that the transformation of N-(4-acetylphenyl)-2-(4-formylphenoxy)acetamide (47.6%) into hydrazide analogs provided remarkable antioxidant activity (78.1, and 60.3%).