Topic
Allose
About: Allose is a research topic. Over the lifetime, 338 publications have been published within this topic receiving 5239 citations. The topic is also known as: allo-hexose.
Papers published on a yearly basis
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Papers
TL;DR: An all‐atom additive empirical force field for the hexopyranose monosaccharide form of glucose and its diastereomers allose, altrose, galactose, gulose, idose, mannose, and talose is presented.
Abstract: We present an all-atom additive empirical force field for the hexopyranose monosaccharide form of glucose and its diastereomers allose, altrose, galactose, gulose, idose, mannose, and talose. The model is developed to be consistent with the CHARMM all-atom biomolecular force fields, and the same parameters are used for all diastereomers, including both the alpha- and beta-anomers of each monosaccharide. The force field is developed in a hierarchical manner and reproduces the gas-phase and condensed-phase properties of small-molecule model compounds corresponding to fragments of pyranose monosaccharides. The resultant parameters are transferred to the full pyranose monosaccharides, and additional parameter development is done to achieve a complete hexopyranose monosaccharide force field. Parametrization target data include vibrational frequencies, crystal geometries, solute-water interaction energies, molecular volumes, heats of vaporization, and conformational energies, including those for over 1800 monosaccharide conformations at the MP2/cc-pVTZ//MP2/6-31G(d) level of theory. Although not targeted during parametrization, free energies of aqueous solvation for the model compounds compare favorably with experimental values. Also well-reproduced are monosaccharide crystal unit cell dimensions and ring pucker, densities of concentrated aqueous glucose systems, and the thermodynamic and dynamic properties of the exocyclic torsion in dilute aqueous systems. The new parameter set expands the CHARMM additive force field to allow for simulation of heterogeneous systems that include hexopyranose monosaccharides in addition to proteins, nucleic acids, and lipids.
502 citations
TL;DR: In this paper, an intrinsic kinetic preference for ribose 2,4-diphosphate and all-hexose 2.4,5-triphosphate formation was demonstrated.
Abstract: Glycoaldehyde phosphate aldomerizes in aq. NaOH to a product mixt. contg. the racemates of two diastereomeric tetrose 2,4-diphosphates and 8 hexose 2,4,5-triphosphates. The aldomerization of glycoaldehyde in the presence of formaldehyde is a variant of the formose reaction. It avoids the formation of complex formose product mixts., because C(2)-phosphorylated aldoses cannot undergo aldose-ketose tautomerization. This work, with its demonstration of an intrinsic kinetic preference for ribose 2,4-diphosphate and allose 2,4,5-triphosphate formation, adds a piece of factual chem. information to ongoing discussion about the origin of ribonucleic acids. [on SciFinder (R)]
210 citations
TL;DR: Complex formation can change the conformational equilibrium of methyl β-D-ribopyranoside and β -D-lyxopyranose; it will change the anomeric equilibrium of allose, gulose, ribose, and lyxose; in the presence of calcium or strontium chlorides, methyl glycosides can be synthesized which normally are only minor products of methanolysis.
Abstract: Cyclitols and sugars containing an axial-equatorial-axial sequence of three hydroxyl groups in a six-membered ring, or a cis-cis sequence in a five-membered ring, form 1:1 complexes with metal cations in hydroxylic solvents. At least one of the hydroxyl groups can be replaced by a methoxy group without substantially affecting complex formation. Lanthanum(III) forms the strongest complexes (K about 10 mol−11 in water), followed by calcium and strontium. Complex formation causes downfield shifts of the signals in the p.m.r. spectrum, that of the hydrogen atom vicinal to the oxygen atom central in the ax-eq-ax sequence being the largest.
Complex formation will change the conformational equilibrium of methyl β-D-ribopyranoside and β-D-lyxopyranose; it will change the anomeric equilibrium of allose, gulose, ribose, and lyxose. It will also alter the equilibrium in methanol between the methyl glycosides of the above-mentioned sugars; in the presence of calcium or strontium chlorides, methyl glycosides can be synthesized which normally are only minor products of methanolysis. Complex formation makes possible the separation of some sugars by electrophoresis and on ion-exchange columns.
153 citations
TL;DR: The present study emphasizes that the saccharide family provides, not only valuable information of the structural requirements for the design of new gelators, but also for molecular assembly systems in general.
91 citations
Related Topics (5)
Performance Metrics
| Year | Papers |
|---|---|
| 2022 | 1 |
| 2021 | 5 |
| 2020 | 7 |
| 2019 | 5 |
| 2018 | 6 |
| 2017 | 2 |