title: Structure determination of baeckeins C and D from the roots of Baeckea frutescens.
abstract: Baeckeins C (compound 1) and D (compound 2), a pair of new diastereomeric biflavonoids, were isolated from the roots of Baeckea frutescens. Their structures were elucidated on the basis of spectroscopic analysis, including HR-ESI-MS and one- and two-dimensional NMR spectra ((1)H and (13)C NMR, HSQC, HMBC, and ROESY). The absolute configurations of the 2,3-epoxide moiety for compounds 1 and 2 were determined by circular dichroism spectrometry combined with quantum chemical calculations.
authors: Key Laboratory of Modern Chinese Medicines, Ministry of Education, China Pharmaceutical University, Nanjing 210009, China.
authors: Bei-Xi
authors: BX
authors: Jia
authors: Yu-Xin
authors: YX
authors: Zhou
authors: Xiao-Qing
authors: XQ
authors: Chen
authors: Xiao-Bing
authors: XB
authors: Wang
authors: Jie
authors: J
authors: Yang
authors: Mao-Xiang
authors: MX
authors: Lai
authors: Qiang
authors: Q
authors: Wang
mesh_terms: D005419:Flavonoids / Q000737:chemistry / Q000302:isolation & purification*; D008968:Molecular Conformation; D027822:Myrtaceae / Q000737:chemistry*; D018517:Plant Roots / Q000737:chemistry*; D013237:Stereoisomerism
chemical_list: D005419:Flavonoids; C570012:baeckein C; C570011:baeckein D