The anti-hyperlipidemic effect and constituents of the 19α- hydroxyursane-type triterpenoid fraction obtained from the leaves of Rubus crataegifolius

To demonstrate anti-hyperlipidemic activity of the 19α-hydroxyursane- type triterpenoid (19α-HUT)-rich fraction, this fraction was prepared from the extract of Rubus crataegifolius leaves. This fraction was found to have anti-hyperlipidemic effect in a high fat diet-induced rat model from the observation of reduction of abdominal fat pad weights, atherogenic index and hypercholesterolemia at 30 and 60 mg/kg (p.o.) The 19α-HUT fraction was subjected to SiO₂, ODS, and/or Sephadex LH-20 column chromatography to yield a new triterpenoid (1) called pomolic acid ester along with nine known triterpenoids which are all 19α-HUTs: euscaphic acid (2), tormentic acid (3), 23-hydroxytormentic acid (4), kaji-ichigoside F₁ (5), rosamultin (6), niga-ichigosides F₁ (7) and F₂ (8), suavissimoside F₁ (9) and coreanoside F₁ (10). The structure of compound 1 was established as 28-O-formyl-3,19-dihydroxyurs-12-en-28-oic acid on the basis of 2D-NMR spectroscopic data and mass spectrum. Compound 1 was isolated for the first time from natural sources.