Fliplike motion in the thalidomide dimer: Conformational analysis of (R)-thalidomide using vibrational circular
Hiroshi Izumi1, Shigeru Futamura, Nakako Tokita
1National Institute of Advanced Industrial Science and Technology (AIST), AIST Tsukuba West, 16-1 Onogawa, Tsukuba, Ibaraki 305-8569, Japan. izumi.h@aist.go.jp
Abstract:
The dynamic fliplike motion in the (R)-thalidomide dimer has been reported for the first time. The vibrational circular dichroism (VCD) spectrum of (R)-thalidomide in DMSO-d6 indicates the characteristic nu(CO) bands with opposite signs and reflects the structural property of the equatorial configuration of the phthalimide ring. On the other hand, the VCD spectrum of (R)-thalidomide in CDCl3 exhibits a different pattern of nu(CO) bands and suggests the fliplike motion in dimer forms. This novel insight for the dimer forms would be helpful for the understanding of the structure-activity relationship for thalidomide.
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