title: Two new isoflavanones from Erythrina costaricensis.
abstract: Two new isoflavanones, 5,3'-dihydroxy-4'-methoxy-5'-(3-methyl-1,3-butadienyl)-2'',2''-dimethylpyrano[5,6:6,7]isoflavanone (1) and 5,3'-dihydroxy-5'-(3-hydroxy-3-methyl-1-butenyl)-4'-methoxy-2'',2''-dimethylpyrano[5,6:6,7]isoflavanone (2), together with two known isoflavonoids, cristacarpin, and euchrenone b10, were isolated from the stems of Erythrina costaricensis. Their structures were established on the basis of spectroscopic evidence. These new compounds are rare isoflavanones, possessing both a 2,2-dimethylpyran substituent and a prenyl analog. The antibacterial activities of 1 and 2 against the methicillin-resistant Staphylococcus aureus were examined.
authors.affiliation: Faculty of Pharmacy, Meijo University, Nagoya, Japan. hitoshi@ccmfs.meijo-u.ac.jp
authors.forename: Hitoshi
authors.initials: H
authors.lastname: Tanaka
authors.forename: Hisanori
authors.initials: H
authors.lastname: Hattori
authors.forename: Tomoko
authors.initials: T
authors.lastname: Oh-Uchi
authors.forename: Masaru
authors.initials: M
authors.lastname: Sato
authors.forename: Ryozo
authors.initials: R
authors.lastname: Yamaguchi
authors.forename: Magoichi
authors.initials: M
authors.lastname: Sako
authors.forename: Yoichi
authors.initials: Y
authors.lastname: Tateishi
mesh_terms: D004895:Erythrina / Q000737:chemistry*; D007529:Isoflavones / Q000737:chemistry*; D015394:Molecular Structure; D018547:Plant Stems / Q000737:chemistry
chemical_list: C539152:5,3'-dihydroxy-4'-methoxy-5'-(3-methyl-1,3-butadienyl)-2'',2''-dimethylpyrano(5,6:6,7)isoflavanone; C539153:5,3'-dihydroxy-5'-(3-hydroxy-3-methyl-1-butenyl)-4'-methoxy-2'',2''-dimethylpyrano(5,6:6,7)isoflavanone; D007529:Isoflavones