Vibrational analysis of phosphorothioate DNA: II. The POS group in the model compound dimethyl phosphorothioate [(CH3O)2(POS)]-.
The results of Raman and Infrared (IR) spectroscopic investigations on the vibrational modes of dimethyl phosphorothioate (DMPS) anion, [(CH3O)2(POS)]-, are reported. Ab initio calculations of the vibrational modes, the IR and Raman spectra and the interatomic force constants of DMPS were performed. A normal mode calculation was performed and the results were used to calculate the potential energy distribution for the vibrational modes. This analysis shows that in DMPS the P-S stretching mode has a frequency of about 630 cm-1 and an angle bending mode involving the sulfur atom has a frequency of about 440 cm-1. The proposed vibrational mode assignments will serve as marker bands in the conformational studies of phosphorothioate oligonucleotides which play a central role in the novel antisense therapeutic paradigm.
Steinke
C A
CA
Department of Physics & Astronomy, University of Toledo, OH 43606, USA.
Reeves
K K
KK
Powell
J W
JW
Lee
S A
SA
Chen
Y Z
YZ
Wyrzykiewicz
T
T
Griffey
R H
RH
Mohan
V
V
D004247:DNA / Q000737:chemistry*; D008432:Mathematical Computing; D008958:Models, Molecular; D017550:Spectroscopy, Fourier Transform Infrared; D013873:Thionucleotides / Q000737:chemistry*; D014732:Vibration
D013873:Thionucleotides; D004247:DNA