title: [Flavonoids from Beijing propolis].
abstract: OBJECTIVE
  To separate and identify the active flavonoids from Beijing Propolis.
  
  
  METHODS
  The flavonoids were isolated by column chromatography with silica gel and polyamide, purified with Sephadex LH-20, and elucidated on the basis of NMR, MS, UV, IR and CD spectra.
  
  
  RESULTS
  Six kinds of flavonoids were obtained and elucidated as I: pinostrobin, 5-hydroxy-7-methoxy-flavanone; II: pinocembrin, 5, 7-dihydroxy-flavanone; III: tectochrysin, 5-hydroxy-7-methoxy-flavone; IV: chrysin, 5, 7-dihydroxy-flavone; V: izalpinin, 5-hydroxy-7-methoxy-flavonol and VI: galangin, 5, 7-dihydroxy-flavonol.
  
  
  CONCLUSIONS
  Compounds I, II, III and V were found for the first time from Beijing Propolis.
authors.affiliation: Institute of Medicinal Plant, Chinese Academy of Medical Sciences, Peking Union Medical College, Beijing 100094.
authors.forename: L
authors.initials: L
authors.lastname: Zhou
authors.forename: J
authors.initials: J
authors.lastname: Guo
authors.forename: J
authors.initials: J
authors.lastname: Yu
mesh_terms: D044950:Flavanones; D005419:Flavonoids / Q000737:chemistry / Q000302:isolation & purification*; D008419:Materia Medica / Q000737:chemistry*; D011429:Propolis / Q000737:chemistry*
chemical_list: D044950:Flavanones; D005419:Flavonoids; D008419:Materia Medica; C016063:pinocembrin; D011429:Propolis; C402729:tectochrysin; C411294:pinostrobin