The First Occurrence of A Mallotus 3,4-Seco-Taraxerane Triterpenoid from Mallotus barbatus

he first occurrence of a 3,4-seco-taraxerane triterpenoid in Mallotus species (Euphorbiaceae) is reported. The triterpenoid was isolated from the leaves of the Vietnamese medicinal plant Mallotus barbatus ( Wall.) Muell.-Arg. and its structure was determined to be 3,4-seco-taraxer-14-en-3-oic acid on the basis of HR-MS and NMR spectroscopic methods. For the first time, the 1 H and 13C NMR data and stereochemistry of this compound were fully established on the basis of the 1H- 1H COSY, NOESY, HSQC, and HMBC spectroscopic data.