[Study on the circular dichroism of (S)- and (R)- Wuweizisu C].
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.
Li
Yan-Feng
YF
College of Pharmaceutical Science and Technology, Tianjin University, Tianjin 300072, China.
Dong
Li-Hong
LH
Wang
Wei
W
Wang
Qiang
Q
Wang
Shu-Yang
SY
Zhao
Peng
P
Chang
Jun-Biao
JB
D001713:Biphenyl Compounds / Q000737:chemistry; D002942:Circular Dichroism; D034242:Cyclooctanes / Q000737:chemistry; D017705:Lignans / Q000737:chemistry*; D011083:Polycyclic Compounds / Q000737:chemistry*; D013057:Spectrum Analysis
D001713:Biphenyl Compounds; D034242:Cyclooctanes; D017705:Lignans; D011083:Polycyclic Compounds; C010574:biphenyl; C031409:schizandrin C