Dammarane-Type Triterpene Glycosides from Oncoba manii Active against Methicillin-Resistant Staphylococcus aureus

Abstract

Drug-resistant bacteria are becoming more prevalent both in the community and in hospitals. In a search for new antibiotic leads, we used a high-throughput natural products chemistry approach to isolate one new (1) and two known (2, 3) dammarane-type triterpenes with mass-limited material from the African plant Oncoba manii. The new compound was determined by spectroscopic methods to be 1β,2α,3β,20(R)-tetrahydroxydammar-24-ene 3-O-α-L-rhamnopyranosyl-(1 → 2)-β-D-glucopyranoside. Compounds 1 and 2 inhibited the growth of methicillin-resistant Staphylococcus aureus (MRSA).

Key words

Oncoba manii - Flacourtiaceae - dammarane - chilianoside - methicillin‐resistant Staphylococcus aureus

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