title: Steroidal glycosides from Dregea sinensis var. corrugata screened by liquid chromatography-electrospray ionization tandem mass spectrometry.
abstract: The MS fragmentation behavior of the C-21 steroidal glycosides from Dregea sinensis var. corrugata was investigated by positive and negative ion electrospray ionization MS using a multistage tandem mass spectrometer equipped with an ion trap analyzer. The mass fragmentation patterns of steroidal glycosides substituted with an orthoacetate group were summarized, and the fragmentation patterns were applied to the online structure identification of the steroidal glycosides in the extract. Eighteen new C-21 steroidal glycosides were identified by means of HPLC-HRESIMS and HPLC-DAD-ESIMS(n). Three new compounds (1, 4, and 7) were identified by HPLC-DAD-ESIMS(n), and their structures were elucidated by use of 1D and 2D NMR methods. The structures identified by MS are fully consistent with those elucidated by NMR data. The present study shows that HPLC-DAD-ESIMS(n) can be used as an effective tool to rapidly identify compounds and guide the isolation of target compounds from crude plant extracts.
authors.affiliation: Key Laboratory of Bioactive Substances and Resources Utilization of Chinese Herbal Medicine, Ministry of Education & Institute of Materia Medica, Peking Union Medical College and Chinese Academy of Medical Sciences, No 1 Xian Nong Tan Street, Beijing 100050, People's Republic of China.
authors.forename: Yun-Bao
authors.initials: YB
authors.lastname: Liu
authors.forename: E-Nuo
authors.initials: EN
authors.lastname: Su
authors.forename: Jian-Bei
authors.initials: JB
authors.lastname: Li
authors.forename: Jin-Lan
authors.initials: JL
authors.lastname: Zhang
authors.forename: Shi-Shan
authors.initials: SS
authors.lastname: Yu
authors.forename: Jing
authors.initials: J
authors.lastname: Qu
authors.forename: Jing
authors.initials: J
authors.lastname: Liu
authors.forename: Yong
authors.initials: Y
authors.lastname: Li
mesh_terms: D029062:Apocynaceae / Q000737:chemistry*; D002851:Chromatography, High Pressure Liquid; D004365:Drugs, Chinese Herbal / Q000737:chemistry / Q000302:isolation & purification*; D006027:Glycosides / Q000032:analysis / Q000737:chemistry / Q000302:isolation & purification*; D015394:Molecular Structure; D021241:Spectrometry, Mass, Electrospray Ionization / Q000379:methods; D013256:Steroids / Q000032:analysis / Q000737:chemistry / Q000302:isolation & purification*
chemical_list: D004365:Drugs, Chinese Herbal; D006027:Glycosides; D013256:Steroids