title: [The chemical constituents of Knoxia valerianoides].
abstract: OBJECTIVE
  To study chemical constituents of Knoxia valerianoides Thorel et Pitard.
  
  
  METHODS
  Chromatographic methods were used for the isolation and purification. Structures was elucidated on the basis of chemical analysis and spectroscopic data.
  
  
  RESULTS
  Two anthraquinone were isolated from Knoxia valerianoides Thorel et Pitard and identified as 1,3,5-trihydroxy-2-ethoxymethyl-6-methoxyl-anthraquinone (I) and 1,3-dihydroxy-2-ethoxymethyl-anthraquinone (II).
  
  
  CONCLUSIONS
  The compound I was found to be a novel anthraquinone constituent and II was isolated from Knoxia valerianoides Thorel et Pitard for the first time.
authors.affiliation: Institute of Pharmacology and Toxicology, Academy of Military Medical Sciences, Beijing 100850, China.
authors.forename: Shan-qin
authors.initials: SQ
authors.lastname: Yuan
authors.forename: Yi-min
authors.initials: YM
authors.lastname: Zhao
mesh_terms: D000880:Anthraquinones / Q000737:chemistry / Q000302:isolation & purification*; D015394:Molecular Structure; D035281:Plant Tubers / Q000737:chemistry; D010946:Plants, Medicinal / Q000737:chemistry*; D019666:Rubiaceae / Q000737:chemistry*
chemical_list: C514827:1,3,5-trihydroxy-2-ethoxymethyl-6-methoxyl-anthraquinone; C514828:1,3-dihydroxy-2-ethoxymethyl-anthraquinone; D000880:Anthraquinones