[Conformational variety and physical properties of the 1,2-dideoxyribofuranose-5-phosphate, the model DNA monomer structural unit].

The results of exhaustive quantum-mechanical conformational analysis of 1,2-dideoxyribofuranose-5-phosphate molecule, the model DNA backbone structural unit, are presented. As many as 282 conformations with the relative Gibbs energies from 0 to 8.9 kcal/mole have been obtained at the MP2/cc-pVTZ // DFT B3LYP/cc-pVTZ theory level. Among them seven structures are similar to those of the DNA backbone in its AI, BI and ZII forms, while the B-DNA-like conformation has the lowest Gibbs energy (deltaG = 3.3 kcal/mole). It is shown that the relaxed force constants values for conformational parameters of all DNA-like conformations satisfy inequality K gamma > K alpha > K epsilon > K beta.