Erythritol, oxidation

Fig. 14.2 Relationship between the logarithm of the resistance of D and / Aims of a penta-erythritol alkyd paint, containing 6-1% iron oxide by volume, and the concentration of the potassium chloride solutions in which they were immersed (courtesy Bril. Polym. J., 3, 41...

The chain decomposition of hydroperoxides was proved and studied for hydroperoxides produced by the oxidation of polyesters such as dicaprilate of diethylene glycol and tetra-valerate of erythritol [140], The retarding action of phenolic antioxidant on the decay of hydroperoxides was observed. The initial rate of hydroperoxide decomposition was found to depend on the hydroperoxide concentration in accordance with the kinetic equation typical for the induced chain decomposition. 

Different preparative procedures have been shown to yield protein fractions which are able to catalyze different types of reactions with respect to their requirement of either NAD or NADP as coenzymes [cf. Eqs. (19), (20), and (21)]. In sera of mice poisoned by carbon tetrachloride we found polyol dehydrogenases catalyzing the oxidation of the following polyols (a) with NAD sorbitol, ribitol, mannitol (b) with NADP sorbitol, ribitol. Erythritol and mt/o-inositol were not attacked at all. Figures 8 and 9 show the results of these determinations performed at pH 9.6. In the NAD system sorbitol and ribitol are oxidized at exactly the same rate, while in the NADP system ribitol does not reach the rate of sorbitol. The ratio NAD NADP for sorbitol is calculated to be 4.20 and for ribitol 5.50. Mannitol is oxidized at 23% of the rate of sorbitol. 

The electrochemical oxidation of polyhydric alcohols, viz. ethylene glycol, glycerol, meso-erythritol, xilitol, on a platinum electrode show high reactivity in alkaline solutions of KOH and K2C03 [53]. This electro-oxidation shows structural effects, Pt(lll) being the most active orientation. This results from different adsorption interactions of glycerol with the crystal planes [59]. 

Several compounds have been proposed for the measurement of the void volume, including sodium nitrate solution, water, deuterium oxide, fructose, acetonitrile, tetrahydrofuran (THF), meso-erythritol, gluconolactone, and 2,4-dinitronaphthol. The elution volume of a number of these compounds has been measured in 10-90% aqueous acetonitrile and acidic-aqueous acetonitrile. The results are given in Figure 3.9 where the volumes in A and B were measured in aqueous acetonitrile and in C and D were measured in aqueous acetonitrile containing 50 mM phosphoric acid. Methanol (a) and deuterium oxide (g) showed two peaks when monitored by a refractive index detector (Figure 3.9C). 

Figure 3. Chemical ionization (methane) GC/MS of the acetylated final product derived from periodate oxidation of the myoinositol ring in PSL-I. (a) Total ion chromatogram of co-injected mixture of the unknown dideuterated alcohol product and the authentic erythritol. (b) Chemical ionization spectrum of peak indicated by an arrow in (a). Inset diagrams depict the fragmentation.

These treatments convert to ionic substances, and remove, nearly all constituents of natural materials the acid treatments release any inositol present as phosphate, or combined in phospholipids, glycosides, etc. Glycerol remains in the deionized sample, but it can be oxidized separately, or be removed by heat decomposition or by repeatedly evaporating the solution to dryness. Such polyhydric alcohols of greater chain length as erythritol and mannitol, when present, would still interfere. However, corrections can be made for these compounds by determining the formaldehyde which they form on periodate oxidation, or they may be removed by chromatography on filter paper. The micro-periodate method is well suited to the analysis of samples eluted from filter paper, provided that care is exercised to remove the tiny particles of cellulose which are usually found in such eluates. 

T. Yokozawa, H. Y. Kim, and E. J. Cho, Erythritol attenuates the diabetic oxidative stress through modulating glucose metabolism and lipid peroxidation in streptozotocin-induced diabetic rats, J. Agric. Food Chem., 2002, 50, 5485-5489. 

Benzylidene-D-threitol (VII) was prepared by Haskins, Hann and Hudson79 by hydrogenation of 2,3-benzylidene-D-threose, a product of the periodate oxidation of 2,3-benzylidene-D-arabitol. The tetritol was proved to be D-threitol, rather than erythritol, by the fact that hydrolysis of VII and subsequent treatment with benzaldehyde afforded the known dibenzylidene-D-threitol. The acetal group was allocated to the 2,3-position on the basis of independent evidence concerning the structure of the parent benzylidene-D-arabitol (see page 152). For the physical constants of acetals of threitol see Table VIII. 

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