Monosaccharide esterification

Esterification. The hydroxyl groups of monosaccharides can form esters with acids. In metabolism, phosphoric acid esters such as glucose 6-phosphate and glucose 1-phosphate (6) are particularly important. 

Abstract Polyfunctionality of carbohydrates and their low solubility in conventional organic solvents make rather complex their conversion to higher value added chemicals. Therefore, innovative processes are now strongly needed in order to increase the selectivity of these reactions. Here, we report an overview of the different heterogeneously-catalyzed processes described in the literature. In particular, hydrolysis, dehydration, oxidation, esterification, and etherification of carbohydrates are presented. We shall discuss the main structural parameters that need to be controlled and that permit the conversion of carbohydrates to bioproducts with good selectivity. The conversion of monosaccharides and disaccharides over solid catalysts, as well as recent advances in the heterogeneously-catalyzed conversion of cellulose, will be presented. 

Here we report an overview of the different heterogeneously-catalyzed pathways designed for the selective conversion of carbohydrates. On the basis of these results, we shall try to determine the key parameters allowing a better control of the reaction selectivity. Water being commonly used as solvent in carbohydrate chemistry, we will also discuss the stability of solid catalysts in the aqueous phase. In this review, heterogeneously-catalyzed hydrolysis, dehydration, oxidation, esterification, and etherification of monosaccharides and polysaccharides are reported. 

A. S. Tracey and M. J. Gresser, Vanadium(V) oxyanions Interactions of vanadate with cyclic diols and monosaccharides, Inorg. Chem., 27 (1988) 2695-2702 Vanadium(V) oxyanions the esterification of ethanol with vanadate, J. Am. Chem. Soc., 107 (1995) 4215-4220. 

Arylboronic acids [63,72,80,85,194] have been most extensively studied as binding sites for derivatised monosaccharides. By using an amino group in the position ortho to the boronic add the rate constant for the esterification with a diol has been increased by a factor of 10 , as mentioned above [79], It has also been shown that the flexibility of the boronic add group is crucial. If the binding interaction is too rigid or too flexible, it is detrimental to the selectivity of the... 

The field of monosaccharides, disaccharides and polysaccharids contains many industrial examples of semi-synthesis, which have entered chemical history, such the hydrolysis of starch to form D-glucose, the esterification of cellulose, the chemistry of rayon and, more recently, advances in the chemistry of carbohydrate surfactants (ref.83). 

The absolute configuration of caryose was determined applying the Exciton Chiral Coupling to 36 [Fig. (8)], which is the di-O-p-bromobenzoyl derivative, obtained as the main product of the isopropylidenation of the monosaccharide equilibrium mixture (34a, 34b and 35) followed by esterification with p-bromobenzoyl chloride. The results obtained have suggested for caryose the absolute configuration... 

Show the common reactions of monosaccharides that were presented in this chapter oxidation with nitric acid oxidation with bromine reduction with sodium borohydride esterification glycoside formation and the Kiliani-Fischer synthesis. 

Synthesis. - In a theoretical study on die aBi dation and esterification of monosaccharides, the reactions of 1,6-anhydrO P-D-galactopyranose under diase transfer conditions have been conadered. A MNDO-PM3 study on the sdective activation of 1-0-methoxyacetyl sugars by Zn(II) or Y(in) ions endeavours to explain why 1-0-methoxyacetates are the best donOTs among glycosyl-esters in Lewis add-promoted glycoqiations. ... 

Alkylation of metal chelates of sucrose with allyl halides and sodium bromo-acetate in DMSO yielded mono-O-allylated and mono-O-carboxymethylated derivatives. A new acidic monosaccharide from the O-specific lipopolysaccharide of Shigella dysenteriae type 3 has been identified as 4-0-[(/ )-l-carboxy-ethyl]-D-glucopyranose on the basis of chemical and mass-spectral evidence and by its synthesis by alkylation of methyl 2,3,6-tri-0-benzyl-a(P)-D-glucopyranoside with (5)-2-chloropropionic acid, esterification (with diazomethane), hydrogenolysis, and acid hydrolysis. ... 

Fig. 8.3 Resin glycosides from the whole plant of Ipomoea tricolor and the leaves of I. squamosa, two neotropical vines The structures of tricolorin C and of ipomoeassin E differ remarkably with regard to (i) the hydroxy fatty acid moieties, (ii) the position of their linkage to the oligosaccharide components, (iii) the number and - in part - the types of monosaccharides involved, and (iv) the other acyl residues. Tricolorin H represents a heterodimer of two trisaccharides, tricoloric acid C (highlighted in grey) and an acylated (mba) derivative of the monomeric macrolactone tricolorin G (right), linked to each other by esterification of the jalapinolic add moiety of tricoloric acid C at position C-3" (glu) of the macrolactone part...

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