title: [Study on the circular dichroism of (S)- and (R)- Wuweizisu C].
abstract: The circular dichroism (CD) is an excellent method for determining the absolute stereochemistry of organic compounds. The CD spectra of four biphenyl compounds were determined by using CD spectrometer, and two pairs of symmetrical CD spectra were obtained. The absolute configuration of biphenyl bond was confirmed by the Cotton effect according to the CD rule. The CD spectrum of compound 3 shows a negative Cotton effect at 256 nm, and a positive Cotton effect at 220 nm, which predicts an S-configuration of biphenyl according to an experimental CD rule. Conversely, the CD spectrum of compound 3' displays a positive Cotton effect at 256 nm, and a negative Cotton effect at 219 nm, which predicts an R-configuration of biphenyl. And the regularity of oxazoline-mediated Ullmann reaction was obtained, too.
authors.affiliation: College of Pharmaceutical Science and Technology, Tianjin University, Tianjin 300072, China.
authors.forename: Yan-Feng
authors.initials: YF
authors.lastname: Li
authors.forename: Li-Hong
authors.initials: LH
authors.lastname: Dong
authors.forename: Wei
authors.initials: W
authors.lastname: Wang
authors.forename: Qiang
authors.initials: Q
authors.lastname: Wang
authors.forename: Shu-Yang
authors.initials: SY
authors.lastname: Wang
authors.forename: Peng
authors.initials: P
authors.lastname: Zhao
authors.forename: Jun-Biao
authors.initials: JB
authors.lastname: Chang
mesh_terms: D001713:Biphenyl Compounds / Q000737:chemistry; D002942:Circular Dichroism; D034242:Cyclooctanes / Q000737:chemistry; D017705:Lignans / Q000737:chemistry*; D011083:Polycyclic Compounds / Q000737:chemistry*; D013057:Spectrum Analysis
chemical_list: D001713:Biphenyl Compounds; D034242:Cyclooctanes; D017705:Lignans; D011083:Polycyclic Compounds; C010574:biphenyl; C031409:schizandrin C