The Structures of Camelliagenin A, B and C obtained from Camellia Japonica L.

Abstract

Camelliagenin A was oxidized by chromium trioxide to 28-nor-olean-12-ene-3, 16, 22-trione (VIII). From the data of the nuclear magnetic resonance (NMR) spectra, configuration of the C-3 hydroxyl group was decided as β. Formation of the acetonide and the NMR data also proved the configurations of other hydroxyl groups to be 16α, 22α. The structures of the other two genins were also elucidated systematically in relation to camelliagenin A. Thus camelliagenin A, B and C were decided as 3β, 16α, 22α, 28-tetrahydroxy-(I), 23-oxo-3β, 16α, 22α, 28-tetrahydroxy-(II) and 3β, 16α, 22α, 23, 28-pentahydroxy-olean-12-one (III) respectively.