New geranyl flavonoids from the leaves of Artocarpus communis

AbstractFour new geranyl flavonoids1–4 and four known flavonoids5–8 were obtained from the leaves ofArtocarpus communis collected in Indonesia. The planar structures of flavonoids were elucidated by analyses of MS and NMR spectroscopic data. Absolute configurations of1 and2 were determined by ECD spectroscopy. Analyses by HPLC with a chiral-phase column and ECD spectra confirmed that3 and4 were stereoisomeric mixtures and7 and8 were racemic mixtures. The compounds obtained in this study inhibited the enzymatic activities of ubiquitin-specific protease 7 (USP7) and the chymotrypsin-like activity of the proteasome. Among the geranyl flavonoids tested in this experiment, the USP7 inhibitory activity of6 (IC50 value, 0.094  μM) was 55 times more potent than the commercially available positive control, P5091 (IC50 value, 5.2  μM).
Source: Journal of Natural Medicines - Category: Drugs & Pharmacology Source Type: research