Design and synthesis of novel substituted 3-(2-(1,3,4-thiadiazol-2-ylamino)acetyl)-2H-selenopyrano[2,3-b]quinolin-2-ones

Abstract

A simple and efficient method has been developed for construction of 3-(2-(1,3,4-thiadiazol-2-ylamino)acetyl)-2 H -selenopyrano[2,3- b ]quinolin-2-ones (3a–f) . The 3-acetyl-2 H -selenopyrano[2,3- b ]quinolin-2-ones (1a–f) on bromination with glacial acetic acid offered 3-(2-bromoacetyl)-2 H -selenopyrano[2,3- b ]quinolin-2-ones (2a–f) , these intermediates undergoes coupling with 1,3,4-thiadiazol-2-amine in the presence of potassium carbonate in dimethylformamide to get the title compounds. The present methodology provides an attractive approach to various substituted 3-acetyl-2 H -selenopyrano[2,3- b ]quinolin-2-ones ring with the 1,3,4-thiadiazol-2-amine heterocycle in one condensed molecule in moderate to good yields with favorable functional group tolerance, which has the advantages of operation simplicity, readily available starting materials, scale-up synthesis.