Synthesis and anti-proliferative activity of novel oxepin-annulated coumarins

Abstract

A series of fused dihydrooxepino[h]-and dihydrooxepino[g]coumarins (7 and 8) were synthesized through allylation, Claisen rearrangement, allylation and ring-closing metathesis (RCM), respectively. All the synthesized compounds were characterized by appropriate spectral analysis. The anti-proliferative activities of compound 5a-c, 6a, 6c, 7a-c and 8a-c were evaluated against human colon cancer (Caco-2), liver cancer (HepG2) and breast cancer (SKBR-3) cell lines using tamoxifen (TAM) as the positive control. Compound 7b showed significant anti-proliferative activity against resistant Caco-2 and SKBR-3 cell lines on comparison with all other coumarin derivatives. Interestingly, compound 8b was more potent than TAM against sensitive HepG2 cell line.