Ab initio modelling of the anomeric and exo anomeric effects in 2-methoxytetrahydropyran and 2-methoxythiane corrected for intramolecular BSSE

Oxygen substitution in 2-methoxytetrahydropyran by sulphur in 2-methoxythiane approximately doubles the anomeric effect, which slows down enzymatic processing of 2-methoxythiane.

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Ab Initio Modeling of Glycosyl Torsions and Anomeric Effects in a Model Carbohydrate: 2-Ethoxy Tetrahydropyran

Biophysical Journal ◽

10.1529/biophysj.106.099986 ◽

2007 ◽

Vol 93 (1) ◽

pp. 1-10 ◽

Cited By ~ 24

Author(s):

H. Lee Woodcock ◽

Damian Moran ◽

Richard W. Pastor ◽

Alexander D. MacKerell ◽

Bernard R. Brooks

Keyword(s):

Ab Initio ◽

Ab Initio Modeling ◽

Anomeric Effects

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On the generalized valence bond description of the anomeric and exo-anomeric effects: an ab initio conformational study of 2-methoxytetrahydropyran

Carbohydrate Research ◽

10.1016/j.carres.2005.07.001 ◽

2005 ◽

Vol 340 (13) ◽

pp. 2171-2184 ◽

Cited By ~ 19

Author(s):

Rodrigo S. Bitzer ◽

André G.H. Barbosa ◽

Clarissa O. da Silva ◽

Marco A.C. Nascimento

Keyword(s):

Ab Initio ◽

Valence Bond ◽

Conformational Study ◽

Generalized Valence Bond ◽

Anomeric Effects

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Ab Initio Study and NBO Interpretation of the Anomeric Effect in CH2(XH2)2(X = N, P, As) Compounds

The Journal of Physical Chemistry A ◽

10.1021/jp001937p ◽

2000 ◽

Vol 104 (41) ◽

pp. 9362-9369 ◽

Cited By ~ 23

Author(s):

Luis Carballeira ◽

Ignacio Pérez-Juste

Keyword(s):

Ab Initio ◽

Anomeric Effect ◽

Ab Initio Study ◽

Nbo Interpretation

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Sugar anomerism — a short and sweet digression Perspective on “The application of ab initio molecular orbital theory to the anomeric effect”

Theoretical Chemistry Accounts ◽

10.1007/978-3-662-10421-7_43 ◽

2000 ◽

pp. 308-310

Author(s):

Christopher J. Cramer

Keyword(s):

Ab Initio ◽

Molecular Orbital ◽

Anomeric Effect ◽

Molecular Orbital Theory ◽

Orbital Theory

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Heteroatom Substitution at Amide Nitrogen—Resonance Reduction and HERON Reactions of Anomeric Amides

Molecules ◽

10.3390/molecules23112834 ◽

2018 ◽

Vol 23 (11) ◽

pp. 2834 ◽

Cited By ~ 8

Author(s):

Stephen Glover ◽

Adam Rosser

Keyword(s):

Amide Bond ◽

Anomeric Effect ◽

Amide Nitrogen ◽

Carbonyl Carbon ◽

Heteroatom Substitution ◽

Electronegative Atom ◽

Anomeric Effects ◽

Acyl Derivatives

This review describes how resonance in amides is greatly affected upon substitution at nitrogen by two electronegative atoms. Nitrogen becomes strongly pyramidal and resonance stabilisation, evaluated computationally, can be reduced to as little as 50% that of N,N-dimethylacetamide. However, this occurs without significant twisting about the amide bond, which is borne out both experimentally and theoretically. In certain configurations, reduced resonance and pronounced anomeric effects between heteroatom substituents are instrumental in driving the HERON (Heteroatom Rearrangement On Nitrogen) reaction, in which the more electronegative atom migrates from nitrogen to the carbonyl carbon in concert with heterolysis of the amide bond, to generate acyl derivatives and heteroatom-substituted nitrenes. In other cases the anomeric effect facilitates SN1 and SN2 reactivity at the amide nitrogen.

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Configuration and conformation of alkoxyalkyl and hydroxyalkyl trifluoromethyl nitroxides. Anomeric effects and nitroxide conformations

Canadian Journal of Chemistry ◽

10.1139/v81-262 ◽

1981 ◽

Vol 59 (12) ◽

pp. 1745-1752 ◽

Cited By ~ 8

Author(s):

C. Chatgilialoglu ◽

K. U. Ingold

Keyword(s):

Anomeric Effect ◽

Conformational Preference ◽

Nodal Plane ◽

Spectral Parameters ◽

Small Magnitude ◽

Or Groups ◽

Steric Factors ◽

Hyperfine Splittings ◽

Anomeric Effects ◽

Configuration And Conformation

The epr spectral parameters for some [Formula: see text] radicals have been measured over a range of temperatures. These radicals are probably non-planar at nitrogen. Their OR groups are in the eclipsed position with respect to the N 2pz orbital, a conformational preference which is attributed to a combination of steric factors and the anomeric effect. For [Formula: see text] the H hyperfine splittings (hfs) are of unusually small magnitude. It is pointed out that all other known [Formula: see text] also have anomalously low H hfs. It is suggested that this is due to the anomeric effect which not only promotes the eclipsed conformation but also causes the OR group to bend towards the semioccupied orbital, thereby moving H and R2 towards the nodal plane of this orbital.

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