D-glucose conversion

Amino 2 deoxy d glucose, conversion of hydrochloride to 2 acetamido-2 deoxy d glucose, 46, 2 l-(Ammomcthyl) cycloheptanol, 46, 31 2 Amino 2 methyl 1 propanol in isolation of levopimanc acid 45, 64 c-Amino p nitrobiphenyl, by nitration of o aminobiphenyl, 46, 86 from o,p dimtrobiphenyl, 46, 88 Amino 2 propanone, semicarbazone... 

Another important feature between H-Y and H-Beta zeolites is the difference observed for the (Ha. ratio of butyl-D-glucopyranosides versus D-glucose conversion (Figure 7.2). The fi/a ratio of pyranosides is higher for H-Y (Si/Al = 15) than for H-Beta (Si/Al =12.5) up to a glucose conversion of 80%. At complete glucose conversion, the thermodynamic (Ha ratio of 0.5 is obtained. 

Figure 7.2 Plot of the [i/a ratio of butyl-D-glucopyranosides versus D-glucose conversion in the presence of different catalysts [ , H-Y (Si/Al = 15) A, H-Beta (Si/Al = 12.5)] for glycosylation of glucose (4.8 g) with n-butanol (50 ml) at 383 K and 1000 rpm agitation speed. Reprinted from J. Catal., Vol. 185, Chapat et al., pp. 445-453, Copyright 1999, with permission from Elsevier...

Amino-2-deoxy-D-glucose, conversion of hydrochloride to 2-acetamido-2-deoxy-D-glucose, 46, 2... 

Selectivity measured at 80% of L-sorbose conversion Selectivity measured at 95% of D-glucose conversion... 

Aminoglycoside Biosynthesis. The biosynthesis of the aminoglycosides has been extensively studied and reviewed (117—119). Perhaps the most interesting aspect is the biosynthesis of 2-deoxystreptamiae (1, R = H), in which the C-1 and C-6 of a D-glucose molecule become the C-1 and C-2 of 2-deoxystreptamiae by way of the intermediate 2-deoxy-j //(9-iaosose. The details of this conversion are stiU unclear. 

P-amylase, and debranching enzymes. Conversion of D-glucose to D-fmctose is mediated by glucose isomerase, mosdy in its immobilized form in columns. Enzymic degradation of starch to symps has been well reviewed (116—118), and enzymic isomerization, especially by immobilized glucose isomerase, has been fiiUy described (119) (see Syrups). 

In all plants and most animals, L-ascorbic acid is produced from D-glucose (4) and D-galactose (26). Ascorbic acid biosynthesis in animals starts with D-glucose (4). In plants, where the biosynthesis is more compHcated, there are two postulated biosynthetic pathways for the conversion of D-glucose or D-galactose to ascorbic acid. 

Fischer s original method for conversion of the nitrile into an aldehyde involved hydrolysis to a carboxylic acid, ring closure to a cyclic ester (lactone), and subsequent reduction. A modern improvement is to reduce the nitrile over a palladium catalyst, yielding an imine intermediate that is hydrolyzed to an aldehyde. Note that the cyanohydrin is formed as a mixture of stereoisomers at the new chirality center, so two new aldoses, differing only in their stereochemistry at C2, Tesult from Kiliani-Fischer synthesis. Chain extension of D-arabinose, for example, yields a mixture of D-glucose and o-mannose. 

Glucose oxidase is specific for P-D-glucose and where a-D-glucose is the available substrate, prior conversion from the a to the P form is required. 

Hydrogenation reactions, particularly for the manufacture of fine chemicals, prevail in the research of three-phase processes. Examples are hydrogenation of citral (selectivity > 80% [86-88]) and 2-butyne-l,4-diol (conversion > 80% and selectivity > 97% [89]). Eor Pt/ACE the yield to n-sorbitol in hydrogenation of D-glucose exceeded 99.5% [90]. Water denitrification via hydrogenation of nitrites and nitrates was extensively studied using fiber-based catalysts [91-95]. An attempt to use fiber-structured catalysts for wet air oxidation of organics (4-nitrophenol as a model compound) in water was successful. TOC removal up to 90% was achieved [96]. 

The reaction of the aldehyde 174, prepared from D-glucose diethyl dithio-acetal by way of compounds 172 and 173, with lithium dimethyl methyl-phosphonate gave the adduct 175. Conversion of 175 into compound 176, followed by oxidation with dimethyl sulfoxide-oxalyl chloride, provided diketone 177. Cyclization of 177 with ethyldiisopropylamine gave the enone 178, which furnished compounds 179 and 180 on sodium borohydride reduction. 0-Desilylation, catalytic hydrogenation, 0-debenzyIation, and acetylation converted 179 into the pentaacetate 93 and 5a-carba-a-L-ido-pyranose pentaacetate (181). 

In case of (3-glucosidation using a large amount of alcohol, the ratio of alcohol, H2O and D-glucose was studied for improvement of conversion yield by Vic and Grout. By applying the reported procedure, a mixture of D-glucose... 

More-specific methods are available for identifying and quantitating the typical, amino sugar component of heparin (and some heparan sulfate species), namely, 2-deoxy-2-sulfoamino-D-glucose. Most of these methods are based on conversion of these residues into 2,5-anhydro-D-mannose by deamination with nitrous acid (see Section VIII,2). The 2,5-anhydro-D-mannose residues may be determined either colorimetrically,52-54 or fluorimetrically.55... 

Glucose isomerase catalyzes the conversion of D-glucose to D-fructose and has also been used extensively on an industrial scale.1184 Some, but not all, enzymes of this family require Co specifically, while others can function with other divalent ions. Environmental and health issues limit the concentrations of Co in culture media during D-fructose production and other metal ions are being sought as substitutes. Although the active site structure remains unknown, EXAFS, optical and EPR spectroscopy has suggest a low-spin divalent Co ion, bound by N and O-donors only (no S-donors). 

The inference is that the hydrofuranol ring of XL can never be directly formed by the saponification of a 3-tosyl ester of D-glucose, but only indirectly by the intermediate formation and scission of an anhydro ring of the ethylene oxide type. The sequence of reactions involved in the conversion of methyl 3-tosyl-jS-D-gIueoside into methyl 3,6-anhydro-n-glucoside is shown by XXXVI to XL. 

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