Chemical constituents from the ethanol extract of Picrorhiza scrophulariiflora were isolated and purified by column chromatography. Their structures were identified by HR-MS, 1D and 2D-NMR, and their cytotoxicity was assessed by CCK-8 assay. Four compounds were isolated and identified as follows: 2β-D-glucosyloxy-3β,16α,20β-trihydroxy-9-methyl-19-norlanosterol-5,25-diene-22-one(1), 2β-D-glucosyloxy-3β,16α,20β-trihydroxy-9-methyl-19-norlanosta-5,24-diene-22-one(2), 25-acetoxy-2β-glucosyloxy-3β,16α,20β-trihydroxy-9-methyl-19-norlanosta-5-ene-22-one(3) and 25-acetoxy-2β-glucosyloxy-3β,16α,20β-trihydroxy-9-methyl-19-norlanosta-5,23-(E)-diene-22-one(4). Compound 1 represents a new cucurbitane glycoside. The half inhibitory concentrations of the 4 compounds exceeded 100 μmol·L~(-1) against four tumor cell lines, indicating no significant cytotoxicity.
Keywords: Picrorhiza scrophulariiflora; cucurbitane glycosides; cytotoxicity.