Abstract
Cardenolide glycosides, affinosides A, C, D, E, F, G, H and J, were isolated from the stem and bark of Anodendron affine DRUCE, and their structures were elucidated. They have the same sugar moiety as affinoside B, 4, 6-dideoxy-3-O-methyl-D-glycero-D-glycero-2-hexosulopyranose, which is doubly linked to the 2α- and 3β-hydroxyl groups of the aglycone with 2'-acetal and 1'-anomeric hydroxyl groups, respectively. The aglycone of A was identified as 2α, 3β, 11α, 14-tetrahydroxy-12-oxo-14β-carda-4, 20 (22)-dienolide-7β, 8β-epoxide. The others were found to be 2α, 3β, 14-trihydroxy-11-oxo-, 2α, 3β, 12α, 14-tetrahydroxy-11-oxo-, and 2α, 3β, 5, 12α, 14-pentahydroxy-11-oxo-5β, 14β-card-20 (22)-enolide (C, E, and G, respectively), and 2α, 3β, 12β, 14-tetrahydroxy-11-oxo-14β-carda-4, 20 (22)-dienolide (F). H, D, and J were Δ16-derivatives of A, C, and F, respectively. C was hydrolyzed to the aglycone by preliminary splitting of the 2-O-2'linkage by NaBH4 reduction, followed by treatment with HCl / acetone.
