title: Two diastereomeric saponins with cytotoxic activity from Albizia julibrissin.
abstract: Two diastereomeric saponins, julibrosides J1 (1) and J9 (2), both of which show cytotoxic activity, were obtained from the stem bark of Albizia julibrissin Durazz. On the basis of chemical and spectral evidence [L.B. Ma et al., Carbohydr. Res., 281 (1996) 35-46], the structure of 1 was revised as 3-O-[beta-D-xylopyranosyl-(1-->2)-alpha-L-arabinopyranosyl-(1-->6) -beta-D-glucopyranosyl]-21-O-[(6S)-2-trans-2-hydroxymethyl-6-methyl-6-O- [4-O-((6R)-2-trans-2,6-dimethyl-6-O-(beta-D-quinovopyranosyl)-2,7- octadienoyl)-beta-D-quinovopyranosyl]-2,7-octadienoyl] acacic acid-28-O-beta-D-glucopyranosyl-(1-->3)-[alpha-L-arabinofuranosyl-(1-->4 )]-alpha-L-rhamnopyranosyl-(1-->2)-beta-D-glucopyranosyl ester. The diastereoisomer 2 of 1 was identified as 3-O-[beta-D-xylopyranosyl-(1-->2)-alpha-L-arabinopyranosyl-(1-->6) -beta-D-glucopyranosyl]-21-O-[(6S)-2-trans-2-hydroxymethyl-6-methyl-6-O- [4-O-((6S)-2-trans-2,6-dimethyl-6-O-(beta-D-quinovopyranosyl)-2,7- octadienoyl)-beta-D-quinovopyranosyl]-2,7-octadienoyl] acacic acid-28-O-beta-D-glucopyranosyl-(1-->3)-[alpha-L-arabinofuranosyl-(1-->4 )]-alpha-L-rhamnopyranosyl-(1-->2)-beta-D-glucopyranosyl ester. Saponin 2 is a new saponin named julibroside J9. Both julibrosides J1 and J9 show good inhibitory action against the KB cancer cell line in vitro.
authors.affiliation: School of Pharmaceutical Sciences, Division of Natural Medicinal Chemistry, Beijing Medical University, PR China.
authors.forename: K
authors.initials: K
authors.lastname: Zou
authors.forename: Y
authors.initials: Y
authors.lastname: Zhao
authors.forename: G
authors.initials: G
authors.lastname: Tu
authors.forename: J
authors.initials: J
authors.lastname: Cui
authors.forename: Z
authors.initials: Z
authors.lastname: Jia
authors.forename: R
authors.initials: R
authors.lastname: Zhang
mesh_terms: D000970:Antineoplastic Agents / Q000737:chemistry; D002240:Carbohydrate Sequence; D002851:Chromatography, High Pressure Liquid; D003603:Cytotoxins / Q000737:chemistry*; D004365:Drugs, Chinese Herbal / Q000737:chemistry*; D007887:Fabaceae / Q000737:chemistry*; D013058:Mass Spectrometry; D008969:Molecular Sequence Data; D019906:Nuclear Magnetic Resonance, Biomolecular; D010936:Plant Extracts / Q000737:chemistry; D018547:Plant Stems / Q000737:chemistry; D010946:Plants, Medicinal / Q000737:chemistry*; D012503:Saponins / Q000737:chemistry*; D013237:Stereoisomerism; D014315:Triterpenes / Q000737:chemistry*; D014407:Tumor Cells, Cultured
chemical_list: D000970:Antineoplastic Agents; D003603:Cytotoxins; D004365:Drugs, Chinese Herbal; D010936:Plant Extracts; D012503:Saponins; D014315:Triterpenes; C098833:julibroside J1