Monosaccharides chemical intermediates

Monosaccharide Chemically Bonded Through Reactive Intermediate... 

The chemical character of the nitro group at various positions in the sugar moiety makes this particular class of functionalized monosaccharides extremely attractive as intermediates for amino, unsaturated, oximino, and deoxy-sugars. 

Hydroxymethylfurfural (HMF), a promising intermediate for chemical production [140], can be produced from glucose (Scheme 1) and fructose by dehydration. Conversion of fructose to HMF using l-H-3-methylimidazolium chloride as both catalyst and solvent was reported to result in 92% yield after only 45 min [141], The conversion of the more abundant substrate, glucose, often results in poor selectivity, but it was successfully converted with 70% yield using a chromium(II) chloride catalyst in [C2mim][Cl] [142, 143], The patented method includes monosaccharides, disaccharides and polysaccharides as substrates [143],... 

The biologically active monosaccharide 3-deoxy-D-ura6//io-heptulosonic acid 7-phosphate (8 DAMP) is an important intermediate in the biosynthesis of aromatic amino acids in plants (the shikimate pathway). As shown in Scheme 2, this compound has been produced in a combined chemical and enzymatic synthesis from racemic V-acetylaspartate 3-semialdehyde (4) and DHAP (1). The four-step synthesis proceeds in an overall yield of 13% (37% for the aldolase reaction). The enzymatic step generates the required, enantiomerically pure, syn aldol adduct compound (5). In view of the broad range of substrates tolerated by FDP aldolase, this method may be applicable to the production of analogs of DAMP. 

ABSTRACT This article describes recent developments in the chemistry of an important family of complex monosaccharides which have diverse structures and participate in a wide range of biological processes. For example 3-deoxy-D-/n nno-2-octulosonic acid (KDO) is a key component of the lipopolysaccharides (LPS) of Grammnegative bacteria, 3-deoxy-D-araftmo-2-heptulosonic acid (DAH) is a key intermediate in the biosynthesis of aromatic amino acids in bacteria and plants. A number of their syntheses that were achieved by homologation reactions of the natural carbohydrate units using enzymatic or chemical methods, as well as by total synthetic approaches are here included. Special emphasis is placed on new methodologies and their correlation with the biosynthetic pathway of the corresponding ulosonic acids. 

Mvo-inositol 1,4-diphosphate (38), the racemate of a metabolite of second messenger myo-inositol 1,4,5-triphosphate and its diphosphorothioate analogue (39) have been synthesised from f 1 -1 2.4 S-di-O-isopropylidene-mvo-inositol by way of phosphite intermediates. Similarly, (-mvo-inositol 1,3,4-triphosphate has been obtained from f W2.4.S-tri-O-benzyl-myo-inositol Phosphite chemistry was also employed in the preparation of diphosphorylated and diphosphonylated Lipid A monosaccharide analogues (40). Related Lipid A components are mentioned in Chapter 9. Methyl 3-deoxv-a-D-manno-oct-2-ulopyranosidonic acid 4-phosphate has been synthesised and its chemical stability studied. ... 

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