A Microwave-Enhanced Synthesis and Biological Evaluation of N-Aryl‑5,6,7,8‑tetrahydrobenzo[4,5]thieno[2,3-d]pyrimidin-4-amines

A series of N-aryl-5,6,7,8-tetra-hydrobenzo[4,5]thieno[2,3-d]pyrimidin-4-amines were synthesized in moderate to good yield by using a microwave-enhanced conditions. The selected compounds were evaluated for their cytotoxic effects (IC50 values) on human pulmonary carcinoma (A549), murine BALB/c spontaneous colon adenocarcinoma (CT26) and human hepatocellular liver carcinoma (HepG2) cell lines in vitro. Amongst these compounds, one compound was found to have the better cytotoxic activity with reference to the standard Erlotinib hydrochloride (Tarceva) against A549 (IC50 = 16.06 ± 0.09 μM) and HepG2 (IC50 = 15.01 ± 0.31 μM) cell lines. Especially, two compounds showed best cytotoxic effects against CT26 (IC50 = 11.38 ± 0.44 μM) and HepG2 (IC50 = 8.51 ± 0.52 μM) cell lines, respectively. The preliminary structure-activity relationships were disclosed and the thieno[2,3-d]pyrimidine skeleton could be exploited to potential antitumor agents in the future.