40010-56-8

Upstream product

• 40010-55-7 α- and β-D-<1-13C>mannose 
• 40010-55-7 <1-13C>-α-D-talopyranose 
• 40010-55-7 ¹³C-C₁-glucopyranose 

Downstream Products

• 117013-19-1 <2-13C>-D-fructose 
• 108311-21-3 <1-13C>-D-fructose 
• 105931-74-6 [2-¹³C]-D-mannopyranoside 
• 40010-55-7 α- and β-D-<1-13C>mannose 
• 64-17-5 ethanol 
• 127-09-3 sodium acetate 
• 25289-18-3 sodium glycolate 
• 312-85-6 sodium lactate 
• 124-38-9 carbon dioxide 
• 1111-72-4 carbon dioxide 
• 498-07-7 levoglucosan 
• 67-47-0 5-hydroxymethyl-2-furfuraldehyde 
• 64-18-6 formic acid 
• 123-76-2 levulinic acid 

Relevant academic research and scientific papers

C-1,C-2 Stereospecific Rearrangements of Aldohexoses by Calcium Ion in Basic Solution

In aqueous or methanolic solution containing Ca(2+) and hydroxide ion, aldoses are rapidly epimerized at C-2.This reaction involves C-1,C-2 stereospecific rearrangement. -D-Mannose is formed from -D-glucose by this reaction.

D-Talose Anomerization: NMR Methods To Evaluate the Reaction Kinetics

The kinetics of anomerization of the aldohexose, D-talose, have been studied by several NMR methods in order to evaluate their limitations, complementarity, and internal consistency and to futher explore the effect of monosaccharide structure on reactivity.By use of Dtalose and 13C NMR spectroscopy, six tautomeric forms were detected and quantitated in aqueous solution: α- and β-talofuranoses, α- and β-talopyranoses, hydrate (1,1-gem-diol), and aldehyde.The 13C (75-MHz) and 1H (620-MHz) NMR spectra of D-talose have been interpreted, yielding chemical shiftsand coupling constants (JHH, JCC, JCH) that have been evaluated in terms of ring configuration and conformation.By use of 13C saturation-transfer NMR (ST-NMR), ring-opening rate constants (kopen) of the four cyclic forms were measured, and ring-closing rate constants (kclose) were calculated from kopen and equilibrium constants.NMR-derived rates of tautomer equilibration obtained after dissolving α-D-talopyranose in aqueous solution were predicted accurately from a computer treatment of the unidirectional rate constants determined by ST-NMR under similar solution conditions.Two-dimensional 13C exchange spectroscopy was applied to obtain overall rate constants of tautomer interconversion; rate constants obtained in this fashion compared favorably with those calculated from the ST-derived unidirectional rate constants using the steady-state approximation.Kinetic results show that anomeric configuration and ring size significantly affect ring-opening and ring-closing rates of monosaccharides.

HYDROXIDE-CATALYZED ISOMERIZATION OF D-(1-13C)MANNOSE: EVIDENCE FOR THE INVOLVEMENT OF 3,4-ENEDIOLS

The KOH-catalyzed isomerization of D-(1-13C)mannose under anaerobic conditions was studied by 13C-n.m.r. spectroscopy.D-(1-13C)Glucose and D-(1-13C)fructose are generated during the reaction, as expected.In addition, however, (6-13C)glucose, (6-13C)mannose, and (6-13C)fructose are produced in small proportions, possibly via symmetrical 3,4-enediol intermediates.The involvement of the latter structures in 13C-label shifting is inferred from the observation of (1-13C)sorbose and (6-13C)sorbose in the reaction mixture.