Novel 3-Substituted 8-Methoxycoumarin Derivatives as Anti-Breast Cancer Drugs.

Scientists have been interested in hybrid coumarin derivatives due to their wide clinical anticancer use. Herein, ethyl 8-methoxycoumarin-3-carboxylate (Compound 1) served as the starting material for the synthesis of a series of novel hybrid coumarin derivatives (Compounds 3–6). Their structure was determined using ¹³C NMR, ¹H NMR, elemental analysis, and mass spectrometry. The in vitro cytotoxic activities of coumarin derivatives (Compounds 3, 5, and 6) and brominated coumarin derivatives (Compounds 4, 8, and 9) against MCF-7 and MDA-MB-231 were evaluated. Several substances have been identified as promising candidates for future study, especially Compound 6 due to its potent activity against β-tubulin (TUB) polymerization, sulfatase, and aromatase enzymes. It also has a role in inducing cell-cycle arrest at the S phase in the MCF-7 cell line, as well as apoptosis. [ABSTRACT FROM AUTHOR]