Antimicrobial and anticancer evaluation of a novel synthetic tetracyclic system obtained by Dimroth rearrangement

Abstract

A series of pyrido[3',2':4,5]thieno[2,3-e][1,2,4]triazolo[4,3-c]pyrimidines were prepared via oxidative cyclization of 4-(2-arylidenehydrazinyl) pyrido[3',2':4,5]thieno[3,2-d]pyrimidines. Dimroth rearrangement of such a series yielded pyrido[3',2':4,5]thieno[2,3-e][1,2,4]triazolo[1,5-c]pyrimidines. A reaction mechanism was proposed and the products were screened for their antimicrobial and anticancer activities. From the antimicrobial screening results, it could be seen that compounds 8c, 9f and 10c showed excellent activity against Gram-positive bacteria while compounds 10d and 8c showed the highest activity against Gram-negative bacteria. The results of the anticancer activities showed that compound 9c was the most active against HepG-2 and MCF-7 with IC50 values of 1.19 and 3.46 μg/mL, respectively.