Lead glycerate

Cellulosics. CeUulosic adhesives are obtained by modification of cellulose [9004-34-6] (qv) which comes from cotton linters and wood pulp. Cellulose can be nitrated to provide cellulose nitrate [9004-70-0] which is soluble in organic solvents. When cellulose nitrate is dissolved in amyl acetate [628-63-7] for example, a general purpose solvent-based adhesive which is both waterproof and flexible is formed. Cellulose esterification leads to materials such as cellulose acetate [9004-35-7], which has been used as a pressure-sensitive adhesive tape backing. Cellulose can also be ethoxylated, providing hydroxyethylceUulose which is useful as a thickening agent for poly(vinyl acetate) emulsion adhesives. Etherification leads to materials such as methylceUulose [9004-67-5] which are soluble in water and can be modified with glyceral [56-81-5] to produce adhesives used as wallpaper paste (see Cellulose esters Cellulose ethers). 

The next stage leads to the transformation of the phosphorylated glyceric acid into pyruvic add, which is then converted into acetaldehyde and C02 by the enzyme carboxylase. As soon as the acetaldehyde is formed it enters into enzymic reaction with the phosphorylated glycer-aldehyde which is dehydrogenated to the acid while the aldehyde becomes ethyl alcohol. 

D-lactic or D-glyceric acid. The dextrorotation of the three phenyl-hydrazides and of the amide of lactic acid leads to the same conclusion... 

Under basic conditions, oxidation of glycerol mainly leads to the formation of glycerate (Scheme 8). By employing a 5 wt% Pd/C catalyst, the selectivity to glycerate can be as high as 70% at 100% conversion at pH = n/4i,i42... 

Scheme 8 Oxidation of glycerol in basic media leads to glyceric acid, using Pd/C or Au/C as catalyst.

Preparation 473.—Lead and Calcium Salts of Glyceric Acid. 

Pb SdU.—A dilute aqueous solution of glyceric acid (p. 249) is neutralised with lead carbonate containing a small quantity of lead oxide. The... 

Since the middle carbon of glyceraldehyde is connected to four different substituents, it is a chiral center leading to two possible forms of glyceraldehyde. D-Glycer-aldehyde is illustrated in figure 12.2 in the Fischer projec-... 

In the second step leading to glycerate-3-phosphate, a phosphate group is transferred from glycerate-1,3-bisphos-phate to ADP. This reaction is catalyzed by 3-phosphoglyc-erate kinase. 

After reduction of the enal with diisobutylaluminium hydride, the Wittig olefination of D-glycer-aldehyde acetonide (7 )-24 with Ph3P=CHCHO gives the ( )-allylic alcohol 129. The Katsuki-Sharpless enantioselective epoxidation [89] applied to 129 allows the preparation of D-arabinitol (= D-lyxitol) and ribitol, a meso alditol (Scheme 13.47). Similarly, Wittig olefination of R)-2A with Ph3P=CHCH(OEt)2, followed by acidic hydrolysis of the diethyl acetal and subsequent reduction of the enal with diisobutylaluminium hydride, provides the (Z)-allylic alcohol 130. Diastereoselective epoxidation and hydrolysis leads to D-arabinitol or xylitol, another meso alditol [90a]. 

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