title: [Triterpenoids and steroids of root of Rubus biflorus].
abstract: OBJECTIVE
  To investigate the chemical constituents of root of Rubus biflorus.
  
  
  METHODS
  Isolation and purification were carried out by silica gel column chromatography and recrystallization and so on. Structural determination of the pure compounds was based on physico-chemical properties and various spectral data analysis (1H-NMR, 13C-NMR, IR, EI-MS).
  
  
  RESULTS
  Five compounds were isolated and identified as follows: lupeol acetate (I), corosolic acid (II), oleanic acid (III), 2alpha-hydroxyoleanolic acid (IV), sitosterol (V).
  
  
  CONCLUSIONS
  All these compounds are isolated from this plant for the first time.
authors.affiliation: School of Chemical Engineering, Northwest Minorities University, Lanzhou 730030, China. kangshuhe@163.com
authors.forename: Shu-He
authors.initials: SH
authors.lastname: Kang
authors.forename: Yong-Qing
authors.initials: YQ
authors.lastname: Shi
authors.forename: Cai-Xia
authors.initials: CX
authors.lastname: Yang
mesh_terms: D009682:Magnetic Resonance Spectroscopy; D015394:Molecular Structure; D009828:Oleanolic Acid / Q000031:analogs & derivatives / Q000737:chemistry / Q000302:isolation & purification; D018517:Plant Roots / Q000737:chemistry; D010946:Plants, Medicinal / Q000737:chemistry*; D027824:Rosaceae / Q000737:chemistry*; D012855:Sitosterols / Q000737:chemistry / Q000302:isolation & purification; D013256:Steroids / Q000737:chemistry / Q000302:isolation & purification*; D014315:Triterpenes / Q000737:chemistry / Q000302:isolation & purification*
chemical_list: D012855:Sitosterols; D013256:Steroids; D014315:Triterpenes; C025473:gamma-sitosterol; D009828:Oleanolic Acid; C113861:corosolic acid; C412811:maslinic acid