title: Sesquiterpene glycosides from the roots of Codonopsis pilosula.
abstract: Three new sesquiterpene glycosides, named codonopsesquilosides A-C (1-3), were isolated from an aqueous extract of the dried roots of Codonopsis pilosula. Their structures including absolute configurations were determined by spectroscopic and chemical methods. These glycosides are categorized as C15 carotenoid (1), gymnomitrane (2), and eudesmane (3) types of sesquiterpenoids, respectively. Compound 1 is the first diglycoside of C15 carotenoids to be reported. Compound 2 represents the second reported example of gymnomitrane-type sesquiterpenoids from higher plants. The absolute configurations were supported by comparison of the experimental circular dichroism (CD) spectra with the calculated electronic CD (ECD) spectra of 1-3, their aglycones, and model compounds based on quantum-mechanical time-dependent density functional theory. The influences of the glycosyls on the calculated ECD spectra of the glycosidic sesquiterpenoids, as well as some nomenclature and descriptive problems with gymnomitrane-type sesquiterpenoids are discussed.
authors.affiliation: State Key Laboratory of Bioactive Substance and Function of Natural Medicines, Institute of Materia Medica, Chinese Academy of Medical Sciences and Peking Union Medical College, Beijing 100050, China; Department of Pharmacy, Xiangya Hospital, Central South University, Changsha 410008, China.
authors.forename: Yueping
authors.initials: Y
authors.lastname: Jiang
authors.affiliation: State Key Laboratory of Bioactive Substance and Function of Natural Medicines, Institute of Materia Medica, Chinese Academy of Medical Sciences and Peking Union Medical College, Beijing 100050, China.
authors.forename: Yufeng
authors.initials: Y
authors.lastname: Liu
authors.affiliation: State Key Laboratory of Bioactive Substance and Function of Natural Medicines, Institute of Materia Medica, Chinese Academy of Medical Sciences and Peking Union Medical College, Beijing 100050, China.
authors.forename: Qinglan
authors.initials: Q
authors.lastname: Guo
authors.affiliation: State Key Laboratory of Bioactive Substance and Function of Natural Medicines, Institute of Materia Medica, Chinese Academy of Medical Sciences and Peking Union Medical College, Beijing 100050, China.
authors.forename: Chengbo
authors.initials: C
authors.lastname: Xu
authors.affiliation: State Key Laboratory of Bioactive Substance and Function of Natural Medicines, Institute of Materia Medica, Chinese Academy of Medical Sciences and Peking Union Medical College, Beijing 100050, China.
authors.forename: Chenggen
authors.initials: C
authors.lastname: Zhu
authors.affiliation: State Key Laboratory of Bioactive Substance and Function of Natural Medicines, Institute of Materia Medica, Chinese Academy of Medical Sciences and Peking Union Medical College, Beijing 100050, China.
authors.forename: Jiangong
authors.initials: J
authors.lastname: Shi
keywords: C15 carotenoid; Campanulaceae; Codonopsesquilosides A−C; Codonopsis pilosula; Eudesmane; Gymnomitrane; Sesquiterpene glycoside