title: Revised structures for senegalensin and euchrenone b(10).
abstract: Two prenylated isoflavones (1 and 2) with a hydroxyisopropyldihydrofuran moiety have been isolated from the wood of Erythrina suberosa var. glabrescence. The structure of compound 1 was in agreement with that of the previously reported senegalensin, isolated from the stem bark of Erythrina senegalensis. The structure of senegalensin was revised from structure 2 to structure 1 by spectroscopic means. Compound 2, the regioisomer of 1, was confirmed as euchrenone b(10) by comparison with the spectral data of the reported euchrenone b(10), isolated from the roots of Euchresta horsfieldii. The structure of 2 was established by 2D NMR spectroscopic analysis and by the X-ray crystallographic analysis of its p-bromobenzoyl derivative (2b).
authors.affiliation: Faculty of Pharmacy, Meijo University, Yagoto, Tempaku-ku, Nagoya 468-8503, Japan. hitoshi@meijo-u.ac.jp
authors.forename: H
authors.initials: H
authors.lastname: Tanaka
authors.forename: M
authors.initials: M
authors.lastname: Doi
authors.forename: H
authors.initials: H
authors.lastname: Etoh
authors.forename: N
authors.initials: N
authors.lastname: Watanabe
authors.forename: H
authors.initials: H
authors.lastname: Shimizu
authors.forename: M
authors.initials: M
authors.lastname: Hirata
authors.forename: M
authors.initials: M
authors.lastname: Ahmad
authors.forename: I
authors.initials: I
authors.lastname: Qurashi
authors.forename: M R
authors.initials: MR
authors.lastname: Khan
mesh_terms: D002850:Chromatography, Gel; D018360:Crystallography, X-Ray; D004895:Erythrina / Q000737:chemistry; D005663:Furans / Q000737:chemistry / Q000302:isolation & purification*; D007529:Isoflavones / Q000737:chemistry / Q000302:isolation & purification*; D009682:Magnetic Resonance Spectroscopy; D008968:Molecular Conformation; D015394:Molecular Structure; D010154:Pakistan; D018517:Plant Roots / Q000737:chemistry; D018547:Plant Stems / Q000737:chemistry; D010946:Plants, Medicinal / Q000737:chemistry*; D013055:Spectrophotometry, Infrared; D013056:Spectrophotometry, Ultraviolet; D013237:Stereoisomerism; D014961:X-Ray Diffraction
chemical_list: D005663:Furans; D007529:Isoflavones; C109428:euchrenone b10; C068505:senegalensin