| Full text | |
| Author(s): |
Total Authors: 4
|
| Affiliation: | [1] Univ Fed Lavras, Dept Chem, BR-37200000 Lavras, MG - Brazil
[2] Univ Estadual Campinas, Inst Chem, BR-13083970 Campinas, SP - Brazil
Total Affiliations: 2
|
| Document type: | Journal article |
| Source: | Carbohydrate Research; v. 396, p. 9-13, SEP 19 2014. |
| Web of Science Citations: | 23 |
| Abstract | |
Four alpha- and three beta-isomers of the D-glucose were optimized in gas phase using ab initio (MP2) and DFT (omega B97X-D) methods, both using the aug-cc-pVDZ basis set. While earlier works suggest that the orientation of the hydroxyl groups is due to intramolecular hydrogen bonds (H-bonds), the present study reveals that most H-bonds forming five-membered rings are either weak or even do not exist. The quantum theory of atoms in molecules (QTAIM) analysis showed only a few cases of H-bond in D-glucose, particularly for those H-bonds forming six-membered rings, while the non-covalent interactions (NCI) analysis indicated that most intramolecular H-bonds are not strong enough to justify the counter-clockwise arrangement of the OH center dot center dot center dot O chains. Natural bond orbital analysis supported the findings obtained from QTAIM and NCI analyses and indicated that the anomeric effect for D-glucose in the gas phase is governed by a balance of steric, electrostatic, and hyperconjugative interactions. (C) 2014 Elsevier Ltd. All rights reserved. (AU) | |
| FAPESP's process: | 11/01170-1 - Physicochemical studies of organic compounds: long range inractions and conformational analysis of organofluorine compounds. |
| Grantee: | Rodrigo Antonio Cormanich |
| Support Opportunities: | Scholarships in Brazil - Doctorate |
| FAPESP's process: | 12/03933-5 - Conformational equilibria and intramolecular interactions for a series of amino-acids: theoretical and experimental approaches |
| Grantee: | Roberto Rittner Neto |
| Support Opportunities: | Regular Research Grants |