title: Separation and identification of three epimeric pairs of new C-glucosyl anthrones from Rumex dentatus by on-line high performance liquid chromatography-circular dichroism analysis.
abstract: Six C-glucosyl anthrones were characterized as three pairs of epimers by on-line high performance liquid chromatography-circular dichroism (HPLC-CD) analysis and isolated from the roots of Rumex dentatus by column chromatography. Their structures were elucidated by mass spectrometry, nuclear magnetic spectroscopy and HPLC-CD analysis. They are 10R-C-beta-D-glucosyl-10-hydroxyemodin-9-anthrone (rumejaposide E, 1) and 10S-C-beta-D-glucosyl-10-hydroxyemodin-9-anthrone (rumejaposide F, 2), 10R-C-beta-D-glucosylemodin-9-anthrone (rumejaposide G, 3) and 10S-C-beta-D-glucosylemodin-9-anthrone (rumejaposide H, 4), 10S-C-beta-D-glucosyl-10-hydroxychrysophanol-9-anthrone (cassialoin, 5) and 10R-C-beta-D-glucosyl-10-hydroxychrysophanol-9-anthrone (rumejaposide I, 6). Rumejaposides F-I (2-4 and 6) were new C-glucosyl anthrones. Rumejaposide E (1) and cassialoin (5) were isolated for the first time in Rumex plants. On-line HPLC-UV-CD analysis was a useful tool for structure elucidating epimeric C-glycosides anthrones 3-6 because of the poor stability of the pure isomers (3 and 4) and the minute quantity of 5 and 6 in the mixture.
authors.affiliation: The MOE Key Laboratory for Standardization of Chinese Medicines, Institute of Chinese Materia Medica, Shanghai University of Traditional Chinese Medicine, 1200 Cailun Road, Shanghai 201203, China.
authors.forename: Jing-Jing
authors.initials: JJ
authors.lastname: Zhu
authors.forename: Chao-Feng
authors.initials: CF
authors.lastname: Zhang
authors.forename: Mian
authors.initials: M
authors.lastname: Zhang
authors.forename: S W Annie
authors.initials: SW
authors.lastname: Bligh
authors.forename: Li
authors.initials: L
authors.lastname: Yang
authors.forename: Zhi-Min
authors.initials: ZM
authors.lastname: Wang
authors.forename: Zheng-Tao
authors.initials: ZT
authors.lastname: Wang
mesh_terms: D000873:Anthracenes / Q000737:chemistry / Q000302:isolation & purification*; D002851:Chromatography, High Pressure Liquid / Q000379:methods*; D002942:Circular Dichroism / Q000379:methods*; D019906:Nuclear Magnetic Resonance, Biomolecular; D010936:Plant Extracts / Q000737:chemistry*; D018517:Plant Roots / Q000737:chemistry; D031804:Rumex / Q000737:chemistry*; D013237:Stereoisomerism
chemical_list: D000873:Anthracenes; D010936:Plant Extracts