Dammarane triterpenoids from Amoora yunnanensis

Four dammarane triterpenoids, 20S,24-epoxy-24,25-dihydroxydammar-3-one, 20S ,23 R,24R-23-chloro-20,24-epoxy-dammarane-3 alpha ,24,25-triol 3-acetate, 2 0S,23R,24S-23-chloro-20,24-epoxy-dammarane-3 alpha ,24,25-triol 3-acetate, and 20S,24-epoxy-24,25-dihydroxy-3,4-secodammar-4(28)-en-3-oic acid, in add ition to eight known dammarane triterpenoids, 3-acetylcabraleadiol, cabrale adiol, cabralea-hydroxylactone, ocotillone, cabraleone, 24,25-dihydroxy-dam mar-20-en-3-one, shoreic acid, and 20S,24-epoxy-25,26,27-trisnor-24-oxo-3,4 -secodammar-4(28)-en-3-oic acid, were isolated from the bark of Amoora yunn anensis. Their structures were elucidated by a combination of 1D and 2D NMR spectral analysis and comparison with closely related compounds.