Capsugenin, a dammarane triterpene from Corchorus capsularis

From the leaves of Corchorus capsularis a new dammarane triterpene glycoside, capsin, has been isolated. Capsin was identified as the 3-glucoside of 20,24-epoxy-3β,12β,25,30-tetrahydroxydammarane from spectral data. Capsin was tentatively assigned the (20S, 24S)-configuration by comparison with data available for similar compounds. One of the oxidation products of the aglycone appears to be a friedo-type derivative, formed by concerted methyl migration on decarboxylation of a C-30 carboxylic acid intermediate.