Carbohydrates carbon disulfide

In carbohydrate chemistry, the most described method for the preparation of saccharidic thionocarbamates involves preliminary introduction of the amine function on a partially or non-protected saccharidic template. The condensation of amino sugars with carbon disulfide or thiophosgene leads to cyclization in 1,3-oxazolidine- or l,3-oxazine-2-thiones. This reaction involves the formation of an intermediate isothiocyanate, which reacts further with a 3- or y-located hydroxyl group. The viability and facility of this process depends on the saccharidic ring size and the inherent strain. Some major rules can be put into light from the cases studied 30... 

Saccharidic templates bearing an amino group in C-2, C-6, C-3, C-5. Generally, an amine located on non-anomeric position reacts similarly through the condensation reaction with carbon disulfide or thiophosgene, the preliminary formed isothiocyanate leads to spontaneous or base-induced cyclization into 1,3-oxazolidine- or l,3-oxazine-2-thiones, as previously mentioned. Several extensive studies are reported about the selective introduction of thionocarbamate moieties on carbohydrate scaffolds.3 22 23 320 34 38... 

The condensation of DMDP with carbon disulfide/dicyclohexylcarbodiimide (DCC) afforded the indolizine derivative—potentially biological active thionocarbamate on carbohydrate scaffold, fused from the nitrogen side. 

Interest in the xanthates of carbohydrates has arisen almost entirely through the importance of the viscose process in the technical production of rayon and related products.126 The selective character of the reaction of carbon disulfide and alkali with polyhydroxy compounds has been studied. Lieser and Nagel126 found that a monoxanthate is formed with polyhydric alcohols and methyl a-D-glucopyranoside when they react with carbon disulfide and aqueous barium hydroxide. The xanthation that has been demonstrated in the cases of glycerol 1,3-dimethyl ether and levoglucosan (LXIX) shows that secondary hydroxyl groups can... 

The most significant discovery in the history of carbohydrate thiocarbonates was reported in 1892 by Cross, Bevan, and Beadle, who found that cellulose reacts with a mixture of aqueous sodium hydroxide and carbon disulfide to give a soluble dithiocarbonate derivative, from which cellulose can be regenerated. This observation, the basis of the Viscose process, was made at a time when only one other polyhydric alcohol thiocarbonate, that of glyceritol, was known. The subsequent industrial development of... 

Carbohydrates, allyloxycarbonates, 123 carbonates of, 151 chloroformyl esters of, 102 conformational analysis of, 12 reaction of, with carbon dioxide, 129 with carbon disulfide, 135 with carbonic acid, 129 with phosgene in acetone, 105 thermochemical properties of, 21 thiocarbonates of, 157 Carbonic acid, esters, 91,92,151 bis(methyl 3,4-0-isopropylidene-/3-D-arabinopyranoside), 2,2 -, 96 bis(1,2,3,4 - tetra - O - acetyl -/J - D - glucose), 6,6 -, 104 cyclic, 103... 

In studying the effects of carbon disulfide exposure on enzyme systems of carbohydrate metabolism, McKee et al. (1943) observed that the succinic-oxidase system was inhibited. They noted a 10% decrease in the activity of this system. Carbohydrate metabolism is crucial in proper neural function thus, succinic-oxidase activity may serve as an appropriate biomarker of nervous system effects (McKee et al. 1943). 

Three other groups are recognized as being unusually susceptible to carbon disulfide alcoholics (including those treated with Antabuse), those with neuropsychic disorders, and those with vitamin B6 deficiency (Djuric et al. 1973 Lefaux 1968 Peters et al. 1982). Carbon disulfide reduces the levels of vitamin B6, which in turn upsets carbohydrate metabolism, particularly the cerebral carbohydrates (Lefaux 1968). 

Goto S, Hotta R, Sugimoto K. 1971. Studies on chronic carbon disulfide poisoning Pathogenesis of retinal microaneurysm due to carbon disulfide, with special reference to a subclinical defect of carbohydrate metabolism. Int Arch Arbeitsmed 28 115-126. 

Sharma SC, Chopra YM. 1981. Effect of carbon disulfide toxicity on carbohydrate metabolism [Abstract], Indian J Biochem Biophys 18 147. 

Besides acetates and benzoates many other types of carboxylic acid esters can be formed, such as chloroacetates, trifluoroacetates, pivalates, carbonates, and thiocarbonates, by reaction with chloroacetic anhydride, trifluoroacetic anhydride, pivaloyl chloride (2,2-dimethyl propanoyl chloride), phosgene or methylchloro-formate, and carbon disulfide or carbonyl sulfide, respectively. Each of the ester derivatives imparts specific chemical properties to the carbohydrates so they can be used selectively in synthetic schemes. It was found that the sulfonic acid esters... 

Figure 5.1 Schematic diagram of the lactoferrin molecule. The positions of carbohydrate attachment are marked with a star. O, ovotransferrin T, human serotransferrin L, human lactoferrin R, rabbit serotransferrin M, melanotransferrin A, the connecting helix B, the C-terminal helix. The disulfide bridges are indicated by heavy bars, and the iron and carbonate binding sites by filled or open circles, respectively. Reprinted from Baker et al., 1987. Copyright (1987), with permission from Elsevier Science.

The most common electrode material used in LC-EC is carbon, either as solid glassy carbon disks in thin-layer cells, or as a high-surface-area porous matrix through which the mobile phase can flow. Gold electrodes are useful to support a mercury film and these are primarily used to determine thiols and disulfides, and also for carbohydrates using pulsed electrochemical detection... 

Carbohydrate derivatives employed as host molecules often posses in their molecular structure other NMR active nuclei than carbon-13, which offer additional probes to investigate subtle structural effects. In particular, phosphorus-31 is an attractive nucleus owing to 100% abundance and high sensitivity. As reported by Potrzebowski and coworkers, bis[6-0,6-0 -( l,2 3,4-diisopropy-lidene-a-D-galactopyranosyl) thiophosphoryl] disulfide (DGTD) shown in... 

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