title: NMR solution structure study of the representative component hydroxysafflor yellow A and other quinochalcone C-glycosides from Carthamus tinctorius.
abstract: Hydroxysafflor yellow A (HSYA), a representative component of Carthamus tinctorius, has attracted much attention because of its remarkable cardiovascular activities. Its structure was originally reported in 1993 and has been widely cited to date. In our experiments, its solution structure was studied using NMR techniques in different solvents, including DMSO-d(6), pyridine-d(5), and CD(3)OH. The results indicate that the structure of HSYA is different than the previously described 1b, with 3-enol-1,7-diketo form. The structure has two keto-enol tautomers (2a and 2b), and 2a, with the 1-enol-3,7-diketo form, is the preferred tautomer. On the basis of this finding, other published quinochalcone C-glycoside structures were revised. Furthermore, a trend in the (13)C NMR data of the (E)-olefinic carbons of quinochalcone C-glycosides is summarized, and a hypothesis is proposed for the relationship between the features of the molecular structure and the preferred keto-enol tautomer.
authors: State Key Laboratory of Bioactive Substance and Function of Natural Medicines, Institute of Materia Medica, Peking Union Medical College and Chinese Academy of Medical Sciences, Beijing, People's Republic of China.
authors: Zi-Ming
authors: ZM
authors: Feng
authors: Jun
authors: J
authors: He
authors: Jian-Shuang
authors: JS
authors: Jiang
authors: Zhong
authors: Z
authors: Chen
authors: Ya-Nan
authors: YN
authors: Yang
authors: Pei-Cheng
authors: PC
authors: Zhang
mesh_terms: D002317:Cardiovascular Agents / Q000737:chemistry / Q000302:isolation & purification* / Q000494:pharmacology; D031187:Carthamus tinctorius / Q000737:chemistry*; D002599:Chalcone / Q000031:analogs & derivatives* / Q000737:chemistry / Q000302:isolation & purification / Q000494:pharmacology; D004365:Drugs, Chinese Herbal / Q000737:chemistry / Q000302:isolation & purification*; D006027:Glycosides / Q000737:chemistry* / Q000302:isolation & purification*; D015394:Molecular Structure; D019906:Nuclear Magnetic Resonance, Biomolecular; D011809:Quinones / Q000737:chemistry* / Q000302:isolation & purification* / Q000494:pharmacology; D013237:Stereoisomerism
chemical_list: D002317:Cardiovascular Agents; D004365:Drugs, Chinese Herbal; D006027:Glycosides; D011809:Quinones; C085278:hydroxysafflor yellow A; D002599:Chalcone