title: [Quantum-mechanical conformational analysis of the 5'-thymidilic acid molecule].
abstract: The conformational analysis of the DNA structural unit--the nucleotide with thymine base and electroneutral phosphate group at 5'-position-has been carried out with the applied quantum mechanics methods at the MP2/6-311++G(d,p) // B3LYP/6-31G(d,p) theory level. As many as 660 conformations with relative Gibbs energies under standard conditions from 0 to 11.1 kcal/mole have been found. Among them, six conformations are similar to the structure of the nucleotide of AI-DNA, one--to AII- and seven--to the DNA in BI-form. The lowest Gibbs energy among the DNA-like conformations (deltaG = 2.7 kcal/mole) belongs to BI-DNA-like structure. It is shown that the glycoside chemical bond is the most labile one. The role of intramolecular CH...O hydrogen bonds in formation of the 5'-thymidilic acid molecule structure is demonstrated.
authors.forename: T Iu
authors.initials: TIu
authors.lastname: Nikolaienko
authors.forename: L A
authors.initials: LA
authors.lastname: Bulavin
authors.forename: D M
authors.initials: DM
authors.lastname: Govorun
mesh_terms: D001696:Biomechanical Phenomena; D006860:Hydrogen Bonding; D008968:Molecular Conformation; D011789:Quantum Theory; D013816:Thermodynamics; D013938:Thymidine Monophosphate / Q000032:analysis / Q000737:chemistry / Q000378:metabolism
chemical_list: D013938:Thymidine Monophosphate