title: Synthesis of flaccidoside II, a bidesmosidic triterpene saponin isolated from Chinese folk medicine Di Wu.
abstract: A total synthesis of flaccidoside II, 3-O-alpha-L-rhamnopyranosyl-(1-->2)-beta-D-xylopyranosyloleanolic acid 28-O-alpha-L-rhamnopyranosyl-(1-->4)-beta-D-glucopyranosyl-(1-->6)-beta-D-glucopyranoside, isolated from Chinese folk medicine Di Wu, has been accomplished from building blocks isopropyl 2-O-acetyl-3,4-di-O-benzoyl-1-thio-beta-D-xylopyranoside, 2,3,4-tri-O-benzoyl-alpha-L-rhamnopyranosyl trichloroacetimidate, oleanolic acid trityl ester, ethyl 2,3-di-O-acetyl-6-O-benzoyl-1-thio-beta-D-glucopyranoside and 4-methoxyphenyl 2,3,4-tri-O-acetyl-beta-D-glucopyranoside. The use of a partially protected thioglycosyl donor significantly simplified the synthesis of the target saponin.
authors: State Key Lab of Environmental Chemistry and Ecotoxicology, Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, PR China.
authors: Shuihong
authors: S
authors: Cheng
authors: Yuguo
authors: Y
authors: Du
authors: Feihong
authors: F
authors: Bing
authors: Guobin
authors: G
authors: Zhang
mesh_terms: D002236:Carbohydrate Conformation; D002240:Carbohydrate Sequence; D004365:Drugs, Chinese Herbal; D008519:Medicine, Traditional; D012503:Saponins / Q000138:chemical synthesis*; D013865:Thioglycosides / Q000737:chemistry; D014315:Triterpenes
chemical_list: C477956:3-O-rhamnopyranosyl-1-2-xylopyranosyl oleanolic acid 28-O-rhamnopyranosyl-1-4-glucopyranosyl-1-6-glucopyranosyl ester; D004365:Drugs, Chinese Herbal; D012503:Saponins; D013865:Thioglycosides; D014315:Triterpenes