Dihydroxyacetone, structure

Suggest a reasonable structure for the intermediate in the con ] version of dihydroxyacetone phosphate to o glyceraldehyde 3 phosphate J... 

An interesting compound having a structure analogous to that of d-fructopyranose is l,3-dihydroxy-2-propanone ( dihydroxyacetone, 24) ... 

Espelt, L., Parella, T., Bujons, J., Solans, C., Joglar, J., Delgado, A. and, Clapes, P., Stereoselective aldol additions catalyzed hy dihydroxyacetone phosphate-dependent aldolases in emulsion systems preparation and structural characterization of linear and cyclic iminopolyols from aminoaldehydes. Chem. Eur. J., 2003, 9, 4887. 

Aspartate can be deaminated to fumarate by bacterial L-aspartate oxidase.2593 This flavoprotein is structurally and mechanistically related to succinate dehydrogenase and can function as a soluble fumarate reductase (p. 1027). However, its main function appears to be to permit the intermediate iminoaspartate to react with dihydroxyacetone-P to form quinolinate, which can be converted to NAD (see Fig. 25-ll).259b... 

Lipid synthesis is unique in that it is almost exclusively localized to the surface of membrane structures. The reason for this restriction is the amphipathic nature of the lipid molecules. Phospholipids are biosynthesized by acylation of either glycerol-3-phosphate or dihydroxyacetone phosphate to form phosphatidic acid. This central intermediate can be converted into phospholipids by two different pathways. In one of these, phosphatidic acid reacts with CTP to yield CDP-diacylglycerol, which in bacteria is converted to phosphatidylserine, phosphatidylglycerol, or diphos-... 

Note that glyceraldehyde and dihydroxyacetone have the same chemical composition, C3H603, but differ in structure (i.e. they are structural isomers). 

As mentioned above, the triacyl-/3-D-ribopyranosyl halides may react with alcohols in the presence of an acid acceptor to give orthoester derivatives. Thus Levene and Tipson56 showed that triacetyl-/3-D-ribopyranosyl bromide reacts with methanol in the presence of silver carbonate to give 3,4-diacetyl-D-ribopyranose methyl 1,2-orthoacetate (LXIV) while Klingensmith and Evans135 obtained an analogous compound (LXV) upon condensing dihydroxyacetone monoacetate with the same halide. The structures of these two orthoesters, LXIV and LXV, have recently been discussed by Pacsu.186... 

Structurally, the parent compound of the simple ketoses is dihydroxyacetone, a structural isomer of glyceraldehyde. 

Although dihydroxyacetone does not possess a chiral carbon atom, the simple ketoses are related to it structurally by the introduction of hydroxylated chiral carbon atoms between the keto group and one of the hydroxymethyl groups. Thus there are two ketotetroses, four ketopentoses, and eight ketohexoses. 

Some ketoses are not related structurally to dihydroxyacetone. They are named by considering the configurations of all the chiral carbon atoms as a unit, ignoring the carbonyl group. 

Although it has not been established by X-ray crystallography that substrate binds to the copper by displacing the equatorial water, this is consistent with graphics modelling based on the 1.7 X-ray structure (Ito et al., 1994). This is consistent with the water proton relaxation data (Knowles et al., 1995) that show that a water proximal to copper can be titrated by the substrate dihydroxyacetone. 

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