Modeling ring puckering in strained systems: Application to 3,6-anhydroglycosides
Different conformations of methyl 3,6-anhydroglycosides with the β-D-galacto, α-D-galacto, and β-D-gluco configurations were studied by molecular mechanics (using the program MM3) and by quantum mechanical (QM) methods at the HF/- and B3LYP/6-31+G** levels, with and without solvent emulation. Using...
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todo:paper_00086215_v340_n12_p2030_Navarro2023-10-03T14:07:06Z Modeling ring puckering in strained systems: Application to 3,6-anhydroglycosides Navarro, D.A. Stortz, C.A. 3,6-Anhydrogalactose Anhydro sugars DFT MM3 Puckering Conformations Glycols Energy differences Molecular mechanics Puckering Quantum theory beta galactosidase beta glucosidase glycoside solvent analytical parameters article calculation carbohydrate analysis chair computer program conformation data analysis energy molecular mechanics molecular model plots and curves priority journal quantum chemistry quantum mechanics Carbohydrate Conformation Computer Simulation Galactose Glycosides Thermodynamics Different conformations of methyl 3,6-anhydroglycosides with the β-D-galacto, α-D-galacto, and β-D-gluco configurations were studied by molecular mechanics (using the program MM3) and by quantum mechanical (QM) methods at the HF/- and B3LYP/6-31+G** levels, with and without solvent emulation. Using molecular mechanics, the energies were plotted against the φ, θ puckering coordinates of Cremer and Pople. In such strained systems, only two extreme conformations of the six-membered ring are likely: 1C4 and B1,4, or any one close to either of them. Results show the preponderance of a distorted chair conformation over that of the distorted boat, though the energy difference is lower and the distortions are larger for the compound with the β-D-galacto configuration. For derivatives of this compound, experimental data in solution indicate both chair and boat forms, depending on the compound and the solvent, whereas for the remaining compounds, experimental data always show the preponderance of the chair conformation. The more accurate DFT calculations lead to the lower energy differences, suggesting that HF and MM3 underestimate the stability of the boat-like conformations. Similar studies on model compounds depict the importance of the anomeric effect in the conformational preferences. © 2005 Elsevier Ltd. All rights reserved. Fil:Navarro, D.A. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales; Argentina. Fil:Stortz, C.A. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales; Argentina. JOUR info:eu-repo/semantics/openAccess http://creativecommons.org/licenses/by/2.5/ar http://hdl.handle.net/20.500.12110/paper_00086215_v340_n12_p2030_Navarro |
| institution |
Universidad de Buenos Aires |
| institution_str |
I-28 |
| repository_str |
R-134 |
| collection |
Biblioteca Digital - Facultad de Ciencias Exactas y Naturales (UBA) |
| topic |
3,6-Anhydrogalactose Anhydro sugars DFT MM3 Puckering Conformations Glycols Energy differences Molecular mechanics Puckering Quantum theory beta galactosidase beta glucosidase glycoside solvent analytical parameters article calculation carbohydrate analysis chair computer program conformation data analysis energy molecular mechanics molecular model plots and curves priority journal quantum chemistry quantum mechanics Carbohydrate Conformation Computer Simulation Galactose Glycosides Thermodynamics |
| spellingShingle |
3,6-Anhydrogalactose Anhydro sugars DFT MM3 Puckering Conformations Glycols Energy differences Molecular mechanics Puckering Quantum theory beta galactosidase beta glucosidase glycoside solvent analytical parameters article calculation carbohydrate analysis chair computer program conformation data analysis energy molecular mechanics molecular model plots and curves priority journal quantum chemistry quantum mechanics Carbohydrate Conformation Computer Simulation Galactose Glycosides Thermodynamics Navarro, D.A. Stortz, C.A. Modeling ring puckering in strained systems: Application to 3,6-anhydroglycosides |
| topic_facet |
3,6-Anhydrogalactose Anhydro sugars DFT MM3 Puckering Conformations Glycols Energy differences Molecular mechanics Puckering Quantum theory beta galactosidase beta glucosidase glycoside solvent analytical parameters article calculation carbohydrate analysis chair computer program conformation data analysis energy molecular mechanics molecular model plots and curves priority journal quantum chemistry quantum mechanics Carbohydrate Conformation Computer Simulation Galactose Glycosides Thermodynamics |
| description |
Different conformations of methyl 3,6-anhydroglycosides with the β-D-galacto, α-D-galacto, and β-D-gluco configurations were studied by molecular mechanics (using the program MM3) and by quantum mechanical (QM) methods at the HF/- and B3LYP/6-31+G** levels, with and without solvent emulation. Using molecular mechanics, the energies were plotted against the φ, θ puckering coordinates of Cremer and Pople. In such strained systems, only two extreme conformations of the six-membered ring are likely: 1C4 and B1,4, or any one close to either of them. Results show the preponderance of a distorted chair conformation over that of the distorted boat, though the energy difference is lower and the distortions are larger for the compound with the β-D-galacto configuration. For derivatives of this compound, experimental data in solution indicate both chair and boat forms, depending on the compound and the solvent, whereas for the remaining compounds, experimental data always show the preponderance of the chair conformation. The more accurate DFT calculations lead to the lower energy differences, suggesting that HF and MM3 underestimate the stability of the boat-like conformations. Similar studies on model compounds depict the importance of the anomeric effect in the conformational preferences. © 2005 Elsevier Ltd. All rights reserved. |
| format |
JOUR |
| author |
Navarro, D.A. Stortz, C.A. |
| author_facet |
Navarro, D.A. Stortz, C.A. |
| author_sort |
Navarro, D.A. |
| title |
Modeling ring puckering in strained systems: Application to 3,6-anhydroglycosides |
| title_short |
Modeling ring puckering in strained systems: Application to 3,6-anhydroglycosides |
| title_full |
Modeling ring puckering in strained systems: Application to 3,6-anhydroglycosides |
| title_fullStr |
Modeling ring puckering in strained systems: Application to 3,6-anhydroglycosides |
| title_full_unstemmed |
Modeling ring puckering in strained systems: Application to 3,6-anhydroglycosides |
| title_sort |
modeling ring puckering in strained systems: application to 3,6-anhydroglycosides |
| url |
http://hdl.handle.net/20.500.12110/paper_00086215_v340_n12_p2030_Navarro |
| work_keys_str_mv |
AT navarroda modelingringpuckeringinstrainedsystemsapplicationto36anhydroglycosides AT stortzca modelingringpuckeringinstrainedsystemsapplicationto36anhydroglycosides |
| _version_ |
1807323221082505216 |