Studies on the constituents of Cimicifuga species. XXVIII. Four new cycloart-7-enol glycosides from the underground parts of Cimicifuga simplex WORMSK

Four new cycloart-7-ene triterpenol arabinosides, bugbanosides C-F, were is olated from the underground parts of Cimicifuga simplex WORMSK. (Ranunculac eae). The structures were elucidated as 12 beta -acetoxy-3 beta ,15 alpha,- 24R,25-tetrahydroxy-16,23-dione-cycloart-7-ene 3-O-alpha -L-arabinopyranosi de, 12 beta -acetoxy-24R,25-epoxy-3 beta, 15 dihydroxy-16,23-dione-cycloart -7-ene 3-O-alpha -L-arabinopyranoside, 12 beta -acetoxy-24R,25-epoxy-3 beta -hydroxy-16,23-dione-cycloart-7-ene 3-O-alpha -L-arabinopyranoside, and 16 ,23R:16,24S-diepoxy-3 beta ,12 beta ,15 alpha ,25-tetrahydroxy cloart-7-ene 3-O-alpha -L-arabinopyranoside on the basis of spectral and chemical evide nce. The circular dichroism (CD) of bugbanosides C-F showed strong negative maxima at 214-217 nm due to a cycloart-7-ene system, as well as other cycl oart-7-ene triterpenes. The CD data showed to be useful in determining basi c skeletons, including absolute stereostructures of cycloart-7-ene triterpe nes.