Eight previously undescribed chromones, named pauciflorins
F–M
and two 5-methyl-2,4-chromadione derivatives named as pauciflorins
N and O, were isolated from the methanol extract of the leaves of Centrapalus pauciflorus (Willd.) H.Rob. together with the
known (+)-spiro-ethuliacoumarin. The structures were determined via
extensive spectroscopic analyses, including HRESIMS, 1D NMR (1H, 13C JMOD), and 2D NMR (HSQC, HMBC, 1H–1H COSY, and NOESY) experiments. Through an MTT
assay, seven isolated compounds were tested for their antiproliferative
properties against human adherent breast (MCF-7, MDA-MB-231), cervical
(HeLa, SiHa), and ovarian (A2780) cancer cell lines. Pauciflorin F
was effective against MCF-7 breast cancer cells, its activity (IC50 5.78 μM) was comparable to that of the reference agent
cisplatin (IC50 5.78 μM).