کد مقاله کد نشریه سال انتشار مقاله انگلیسی نسخه تمام متن
1388331 982783 2009 13 صفحه PDF دانلود رایگان
عنوان انگلیسی مقاله ISI
The (α-1,6) glycosidic bond of isomaltose: a tricky system for theoretical conformational studies
موضوعات مرتبط
مهندسی و علوم پایه شیمی شیمی آلی
پیش نمایش صفحه اول مقاله
The (α-1,6) glycosidic bond of isomaltose: a tricky system for theoretical conformational studies
چکیده انگلیسی
Stable conformations of β-isomaltose (α-d-glucopyranosyl-(1→6)-β-d-glucose) in gas-phase and aqueous solution are investigated in this study using quantum mechanical calculations. Conformational maps are calculated at HF/6-31G(d,p) level and lower energy structures are sampled in the most stable regions. Entropic and thermal corrections are considered and the Boltzmann population is obtained for conformers that are representative of the 18 most stable regions found on the potential energy surface. B3LYP/6-31+G(d,p) and B3LYP/6-311+G(2d,2p) calculations are used in conformational samplings. Solvation effects are considered through the polarizable continuum model approach. Hydroxymethyl group orientations are investigated for the most stable conformers. The influence of electronic correlation and solvation on the glycosidic linkage preference (TG, GT, and GG) and hydroxymethyl group orientation (tg, gt, and gg) are discussed. Heteronuclear spin coupling constants (3JC,H) along the glycosidic linkage are calculated and comparison with other theoretical results and experiments is used to validate the obtained structures.
ناشر
Database: Elsevier - ScienceDirect (ساینس دایرکت)
Journal: Carbohydrate Research - Volume 344, Issue 10, 6 July 2009, Pages 1235-1247
نویسندگان
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