A new pregnane glycoside from Rubus phoenicolasius and its antiproliferative activity

Chemical investigations of the whole plant ethanol extract of Rubus phoenicolasius led to the isolation and identification of a new pregnane glycoside, 3-O-β-glucopyranosyl-3β,15β-dihydroxypregn-5-en-20-one (1), along with other nine known compounds (2-10). All the isolates were reported from this plant for the first time. The structure of compound 1 was determined by detailed analysis of its spectral data including 1D and 2D NMR. In vitro anti-proliferative activities of compounds 1-3 on MCF-7 and NCI-H460 tumour cell lines were evaluated, and compound 1 was active against the two cell lines with IC50 values of 15.6 and 13.5 μM, respectively.