Carbohydrate phosphates

FIGURE 28 5 (a) Tube and (b) space filling models of a DNA double helix The carbohydrate-phosphate backbone is on the out side and can be roughly traced in (b) by the red oxygen atoms The blue atoms belong to the purine and pyrimidine bases and he on the inside The base pairing is more clearly seen in (a)... 

Section 28 8 The most common form of DNA is B DNA which exists as a right handed double helix The carbohydrate-phosphate backbone lies on the outside the punne and pyrimidine bases on the inside The double helix IS stabilized by complementary hydrogen bonding (base pairing) between adenine (A) and thymine (T) and guanine (G) and cytosine (C)... 

Carbohydrate phosphates Adenosine phosphates Intermediates of the mevalonate-independent pathway... 

CZE separation of sugar isomers in a PMMA chip was enhanced by using a phosphate-based, rather than a borate-based buffer. The resolution enhancement may be caused by a rapid carbohydrate-phosphate complex formation process, as compared to a slow carbohydrate-borate complex formation process. To reduce adsorption of the labeled sugar isomers to the PMMA surface, 0.5% methylcel-lulose (viscosity of 2% aqueous solution at 20°C, 4000 cP) was added to the run buffer [560],... 

Typical laboratories have Technicon Auto-analyzers for each of the common repetitive assays (the product of the fermentations, carbohydrates, phosphate, various ions, specific enzymes, etc.). Other equipment generally includes balances, gas chromatographs, high pressure liquid chromato-... 

The synthesis and analysis of carbohydrate phosphates have been collated, and phosphodiesters formed between 2-aminoethanol and polyhydroxylated alcohols or sugars have been synthesized using acetoin enediol pyrophosphate... 

The free-radical chemistry of carbohydrate phosphates exhibits the same characteristics [e.g. reaction (17)], with the additional option that if the free-radical site materializes a to the carbohydrate-ring oxygen atom, ring cleavage may occur (see below). Ribose-5-phosphate [44-49] provides an example for this kind of behaviour. 

Goring, C.A.I. and Bartholomew, W.V. (1950) Microbial products and soil organic matter. Ill Adsorption of carbohydrate phosphates by clays. Soil Science Society of America Proceedings 15, 189-1 94. 

The adsorption of several carbohydrate phosphates by bentonite was studied by Goring and Bartholomew (1951). The sequence of decreasing adsorption of the salts on monovalent cations was phytin > phytin derivatives > fructose 1-6 diphosphate > fruc-tose-6-phosphate > glucose-1-phosphate > glycerophosphoric acid > phosphoglyceric acid. Salts of divalent cations were adsorbed to a greater extent than those of monovalent cations. The carbohydrate phosphates were adsorbed to a much less extent by illite and kaolinite. 

Titanium tetrachloride is an efficient reagent for the conversion of trialkyl phosphites and dialkyl hydrogen phosphonates into dialkyl phosphorochloridates. Imidazolides and dialkyl or diaryl phosphoric acids react with acyl fluorides - benzoyl fluoride and oxalyl difluoride being the reagents of choice - to give quantitative yields of the phosphoryl fluorides. The procedure is adaptable to the preparation of fluorides of carbohydrate phosphates in this field, the reaction between the ceu bohydrate and tris-l//-imidazolylphosphine oxide or sulphide with the replacement of one imidazole... 

Carbohydrate, phosphate buffer, galactose oxidase, catalase, temperature, CUSO4,... 

Carbohydrate phosphates (phosphosaccharides) have a unique significance in biochemistry. They play a vital role in the biosynthesis and metabolism of sugars moreover they are essential components of the nucleic acids and various coenzymes. 

Silnikov described a synthetic route to prepare over fourty 5 -triphosphate dinucleotides with modified carbohydrate-phosphate backbones with the general structure shown [65]. This route employed a combination of solution phase synthesis of the nucleoside dimers followed by the introduction of the triphosphate moiety. The dimers were synthesised from the partially protected nucleoside and 3 -0-/)-chlorophenyl-nucleoside phosphate diester in the presence of 2,4,6-triisopropylbenzenesulfonyl chloride and A -Me-imidazole in pyridine. The pyrophosphate was introduced in a stepwise manner by initial deprotection of the primary alcohol followed by reaction with phosphorus oxychloride in pyridine with subsequent addition of the tetrabutylammonium salt of inorganic pyrophosphate in acetonitrile. 

The reaction of simple a-lithio sulphonate esters with sugar iodides provides a facile route to the sulphonate analogues of important carbohydrate phosphates. When performed with the lithium salts of carbohydrate mesylates, the reaction furnishes sulphonate linked disaccharides. Examples are given in Scheme 12. ... 

Hydroxy- from keto-carboxylic acid esters s. 72, 64 s. a. S. Dalby, G. W. Kenner, and R. C. Sheppard, Soc. 1960, 968 a-Hydroxy- from a-keto-carboxylic acid amides s. 13, 63 3-Hydroxy-2-pyrrolidones from 2,3-pyrrolidiones s. 13,64 Glyeitol — from carbohydrate phosphates G... 

CHESHIRE M.V. and ANDERSON G. 1975. Soil polysaccharides and carbohydrate phosphates. Soil Science, 119, 356-362. 

Figure 1.7. Structures and names of some common and metabolically important carbohydrate phosphates.

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