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Nonconventional NMR Spin-Coupling Constants in Oligosaccharide Conformational Modeling: Structural Dependencies Determined from Density Functional Theory Calculations

[Image: see text] Nonconventional NMR spin-coupling constants were investigated to determine their potential as conformational constraints in MA’AT modeling of the O-glycosidic linkages of oligosaccharides. Four ((1)J(C1′,H1′), (1)J(C1′,C2′), (2)J(C1′,H2′), and (2)J(C2′,H1′)) and eight ((1)J(C4,H4),...

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Autores principales: Meredith, Reagan J., Carmichael, Ian, Serianni, Anthony S.
Formato: Online Artículo Texto
Lenguaje:English
Publicado: American Chemical Society 2022
Acceso en línea:https://www.ncbi.nlm.nih.gov/pmc/articles/PMC9280969/
https://www.ncbi.nlm.nih.gov/pubmed/35847250
http://dx.doi.org/10.1021/acsomega.2c02793
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author Meredith, Reagan J.
Carmichael, Ian
Serianni, Anthony S.
author_facet Meredith, Reagan J.
Carmichael, Ian
Serianni, Anthony S.
author_sort Meredith, Reagan J.
collection PubMed
description [Image: see text] Nonconventional NMR spin-coupling constants were investigated to determine their potential as conformational constraints in MA’AT modeling of the O-glycosidic linkages of oligosaccharides. Four ((1)J(C1′,H1′), (1)J(C1′,C2′), (2)J(C1′,H2′), and (2)J(C2′,H1′)) and eight ((1)J(C4,H4), (1)J(C3,C4), (1)J(C4,C5), (2)J(C3,H4), (2)J(C4,H3), (2)J(C5,H4), (2)J(C4,H5), and (2)J(C3,C5)) spin-couplings in methyl β-d-galactopyranosyl-(1→4)-β-d-glucopyranoside (methyl β-lactoside) were calculated using density functional theory (DFT) to determine their dependencies on O-glycosidic linkage C–O torsion angles, ϕ and ψ, respectively. Long-range (4)J(H1′,H4) was also examined as a potential conformational constraint of either ϕ or ψ. Secondary effects of exocyclic (hydroxyl) C–O bond rotation within or proximal to these coupling pathways were investigated. Based on the findings of methyl β-lactoside, analogous J-couplings were studied in five additional two-bond O-glycosidic linkages [βGlcNAc-(1→4)-βMan, 2-deoxy-βGlc-(1→4)-βGlc, αMan-(1→3)-βMan, αMan-(1→2)-αMan, and βGlcNAc(1→2)-αMan] to determine whether the coupling behaviors observed in methyl β-lactoside were more broadly observed. Of the 13 nonconventional J-couplings studied, 7 exhibit properties that may be useful in future MA’AT modeling of O-glycosidic linkages, none of which involve coupling pathways that include the linkage C–O bonds. The findings also provide new insights into the general effects of exocyclic C–O bond conformation on the magnitude of experimental spin-couplings in saccharides and other hydroxyl-containing molecules.
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spelling pubmed-92809692022-07-15 Nonconventional NMR Spin-Coupling Constants in Oligosaccharide Conformational Modeling: Structural Dependencies Determined from Density Functional Theory Calculations Meredith, Reagan J. Carmichael, Ian Serianni, Anthony S. ACS Omega [Image: see text] Nonconventional NMR spin-coupling constants were investigated to determine their potential as conformational constraints in MA’AT modeling of the O-glycosidic linkages of oligosaccharides. Four ((1)J(C1′,H1′), (1)J(C1′,C2′), (2)J(C1′,H2′), and (2)J(C2′,H1′)) and eight ((1)J(C4,H4), (1)J(C3,C4), (1)J(C4,C5), (2)J(C3,H4), (2)J(C4,H3), (2)J(C5,H4), (2)J(C4,H5), and (2)J(C3,C5)) spin-couplings in methyl β-d-galactopyranosyl-(1→4)-β-d-glucopyranoside (methyl β-lactoside) were calculated using density functional theory (DFT) to determine their dependencies on O-glycosidic linkage C–O torsion angles, ϕ and ψ, respectively. Long-range (4)J(H1′,H4) was also examined as a potential conformational constraint of either ϕ or ψ. Secondary effects of exocyclic (hydroxyl) C–O bond rotation within or proximal to these coupling pathways were investigated. Based on the findings of methyl β-lactoside, analogous J-couplings were studied in five additional two-bond O-glycosidic linkages [βGlcNAc-(1→4)-βMan, 2-deoxy-βGlc-(1→4)-βGlc, αMan-(1→3)-βMan, αMan-(1→2)-αMan, and βGlcNAc(1→2)-αMan] to determine whether the coupling behaviors observed in methyl β-lactoside were more broadly observed. Of the 13 nonconventional J-couplings studied, 7 exhibit properties that may be useful in future MA’AT modeling of O-glycosidic linkages, none of which involve coupling pathways that include the linkage C–O bonds. The findings also provide new insights into the general effects of exocyclic C–O bond conformation on the magnitude of experimental spin-couplings in saccharides and other hydroxyl-containing molecules. American Chemical Society 2022-07-01 /pmc/articles/PMC9280969/ /pubmed/35847250 http://dx.doi.org/10.1021/acsomega.2c02793 Text en © 2022 The Authors. Published by American Chemical Society https://creativecommons.org/licenses/by-nc-nd/4.0/Permits non-commercial access and re-use, provided that author attribution and integrity are maintained; but does not permit creation of adaptations or other derivative works (https://creativecommons.org/licenses/by-nc-nd/4.0/).
spellingShingle Meredith, Reagan J.
Carmichael, Ian
Serianni, Anthony S.
Nonconventional NMR Spin-Coupling Constants in Oligosaccharide Conformational Modeling: Structural Dependencies Determined from Density Functional Theory Calculations
title Nonconventional NMR Spin-Coupling Constants in Oligosaccharide Conformational Modeling: Structural Dependencies Determined from Density Functional Theory Calculations
title_full Nonconventional NMR Spin-Coupling Constants in Oligosaccharide Conformational Modeling: Structural Dependencies Determined from Density Functional Theory Calculations
title_fullStr Nonconventional NMR Spin-Coupling Constants in Oligosaccharide Conformational Modeling: Structural Dependencies Determined from Density Functional Theory Calculations
title_full_unstemmed Nonconventional NMR Spin-Coupling Constants in Oligosaccharide Conformational Modeling: Structural Dependencies Determined from Density Functional Theory Calculations
title_short Nonconventional NMR Spin-Coupling Constants in Oligosaccharide Conformational Modeling: Structural Dependencies Determined from Density Functional Theory Calculations
title_sort nonconventional nmr spin-coupling constants in oligosaccharide conformational modeling: structural dependencies determined from density functional theory calculations
url https://www.ncbi.nlm.nih.gov/pmc/articles/PMC9280969/
https://www.ncbi.nlm.nih.gov/pubmed/35847250
http://dx.doi.org/10.1021/acsomega.2c02793
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