Six pairs of enantiomeric prenylated flavonoids with cytotoxic activities from Epimedium sagittatum Maxim.

Abstract

In this work, six pairs of undescribed enantiomeric prenylated flavonoids, ( ±)-epimesatines J-O (1a/1b-6a/6b), were isolated from the aerial parts of Epimedium sagittatum Maxim. Their structures and absolute configurations were determined based on spectroscopic data, quantum chemical calculations of electronic circular dichroism (ECD) and ¹³C NMR, as well as ECD experiments induced by Mo₂(OAc)₄ and Rh₂(OCOCF₃)₄. The cytotoxicity assay revealed that compounds 1a/1b, 2a/2b, and 4a/4b-6a/6b demonstrated significant inhibitory effects on the viability of human breast cancer cells MCF-7 while exhibiting no obvious toxicity towards human breast epithelial cells MCF-10A. Additionally, these compounds were found to decrease the expression of sphingosine kinase 1 (Sphk1) in MCF-7 cells. Notably, compounds 4a and 5b exhibited IC₅₀ values of 7.45 and 8.97 μM, respectively, in MCF-7 cells.