Studies on the Constituents of Cimicifuga Species. XX. Absolute Stereostructures of Cimicifugoside and Actein from Cimicifu simplex WORMSK.

The absolute stereostructues of cimicifugoside (1) and actein (2) from Cimicifuga simplex were established by X-ray crystal analysis of 26(S)-O-methylcimicifugenin A (1cS) prepared from 1, negative CD curves of 26-O-methyl-3-keto-cimicifugenins (1dS, 1dR), comparative analysis of 1H- and 13C-NMR spectra of 1, 2 and their derivatives, and preparation of 2 from 1 by hydrogenation : 20(R), 23(R), 24(R), 25(S), 26(R, S)-16β : 23; 23 : 26; 24 : 25-triepoxy-12β-acetoxy-3β, 26-dihydroxy-9, 19-cyclolanost-7-ene 3-O-β-D-xylopyranoside for 1 and 20(R), 23(R), 24(R), 25(S), 26(R, S)-16β : 23; 23 : 26; 24 : 25-triepoxy-12β-acetoxy-3β, 26-dihydroxy-9, 19-cyclolanostane 3-O-β-D-xylopyranoside for 2.