title: New antioxidant phenylethanol glycosides from Torenia concolor.
abstract: Two new phenylethanol glycosides, phenylethyl-O-alpha-l-rhamnopyranosyl-(1 --> 2)-beta-D-glucopyranoside (torenoside A, 1) and 2'-O-3,4-dihydroxy-beta-phenylethoxy-O-alpha-L-rhamnopyranosyl-(1'' --> 3')-(4'-O-caffeoyl)-beta-D-glucopyranoside (torenoside B, 2), along with the 17 known compounds (3-19) were isolated from Torenia concolor. Those structures were established on the basis of spectroscopic analysis including NMR spectroscopic techniques (13C, 1H, 1H-1H COSY, HMQC, HMBC, TOCSY, and NOESY). Moreover, phenylethanol glycosides 3-6 exhibited significant antioxidant activities in DPPH radical scavenging assay.
authors.affiliation: Graduate Institute of Chinese Pharmaceutical Sciences, China Medical University, Taichung, Taiwan.
authors.forename: Yu-Shiang
authors.initials: YS
authors.lastname: Chou
authors.forename: Yu-Ling
authors.initials: YL
authors.lastname: Ho
authors.forename: Chih-Wen
authors.initials: CW
authors.lastname: Ding
authors.forename: Yuan-Shiun
authors.initials: YS
authors.lastname: Chang
mesh_terms: D000975:Antioxidants / Q000737:chemistry / Q000302:isolation & purification* / Q000494:pharmacology*; D001713:Biphenyl Compounds / Q000494:pharmacology; D006027:Glycosides / Q000737:chemistry / Q000302:isolation & purification* / Q000494:pharmacology*; D015394:Molecular Structure; D019906:Nuclear Magnetic Resonance, Biomolecular; D010626:Phenylethyl Alcohol / Q000031:analogs & derivatives* / Q000302:isolation & purification* / Q000494:pharmacology*; D010851:Picrates / Q000494:pharmacology; D010946:Plants, Medicinal / Q000737:chemistry*; D028083:Scrophulariaceae / Q000737:chemistry*; D013624:Taiwan
chemical_list: D000975:Antioxidants; D001713:Biphenyl Compounds; D006027:Glycosides; D010851:Picrates; C004931:1,1-diphenyl-2-picrylhydrazyl; D010626:Phenylethyl Alcohol