Two New Cucurbitane Triterpenoids from Immature Fruits of Momordica charantia

Two new cucurbitane triterpenoids, kuguacin X (1) and kuguaglycoside I (2), together with three known analogs, were isolated from immature fruits of Momordica charantia. By detailed analysis of IR, NMR, and MS data, acid hydrolysis, and comparison with spectroscopic data of known compounds, the new compounds were determined to be (23E)-5 beta,19-epoxycucurbita-6,23-diene-3 beta,22 xi,25-triol (1) and (23E)-5 beta,19-epoxycucurbita-6,23-dien-19-on-3 beta,25-diol 3-O-beta-D-allopyranoside (2).