The plant material, Dysoxylum cumingianum was collected from Orchid Island, Taiwan, in April 2012 and identified by one of the authors (Y.C.S.). The CUMA isolation and purification protocols were modified and simplified from previously published studies (Kashiwada, 1992; Kurimoto et al., 2011). The acetone extract from the leaves and twigs of Dysoxylum cumingianum was partitioned to yield EA-fraction which was further subjected to extensive chromatographic separation using Sephadex LH-20 column, silica gel column, and in the final step purified by preparative reverse phase high-performance liquid chromatography (Cosmosil 5C18-AR-II column, Nacali Tesque, Kyoto, Japan) (Figure S1) to obtain pentacyclic triterpene glucoside, cumingianoside A (CUMA, Figure 1A) with ?95% purity as judged by NMR spectrometry (AVII-500 NMR spectrometer, Brüker, Karlsruhe, Germany) (Figure S2B and S2C). The structure was elucidated as 3-O-acetyl-3?,7?,23,24,25-pentahydroxy-14,18-cycloapoeuphanyl 7-O-?-D-(6?-O-acetyl) glucopyranoside on the basis of 1H and 13C NMR and electron spray ionization mass spectrometry (ThermoFinnigan LCQ) (Figure S2) and in comparison to previously published results (Kashiwada, 1992).