Synthesis of Some Medicinal and Biological Active (2E)-2-(5-Substituted 2-thienylmethylene)-4-oxo-4- arylbutanamides and (2E,3Z)-4-hydroxy-4-aryl-2-(5-substituted thien-2-ylmethylene)but-3-enohydrazides

Abstract

Solvent-free microwave irradiation of (3E)-5-phenyl-3-(2-thienylmethylene)furan-2(3H)-one 1, (3E)-5-(4- methylphenyl)-3-(2-thienylmethylene)furan-2(3H)-one 2, and (3E)-3-[(5-methyl-2-thienyl)methylene]-5- phenylfuran-2(3H)-one 3 with aromatic and aliphatic amines (a-g and i) gave the corresponding (2E)-2-(5- substituted 2-thienylmethylene)-4-oxo-4-arylbutanamides 4-10, 12, 13-19, 21, 22-28, and 30. However, reaction of furanones 1-3 with hydrazine hydrate (h) gave (2E,3Z)-4-hydroxy-4-phenyl-2-(thien-2-ylmethylene)but-3- enohydrazide 11, (2E,3Z)-4-hydroxy-4-(4-methylphenyl)-2-(thien-2-ylmethylene)but-3-enohydrazide 20, and (2E,3Z)-4-hydroxy-2-[(5-methylthien-2-yl)methylene]-4-phenylbut-3-enohydrazide 29, respectively. Comparison between microwave-assisted and thermal heating synthesis of compounds 4-30 showed that microwave irradiation significantly reduces the reaction time with the enhancement of yields and purity. Structural formulas of synthesized compounds were assigned by their spectral data. Mechanisms of reactions are proposed. Some synthesized products showed antibacterial and cytotoxic activity.