5-Keto-gluconic acid

Saito K, Kasai Z 1984 Synthesis of L-(+)-tartaric acid from L-ascorbic add via 5-keto-gluconic acid in grapes. Plant Physiol 76 170-174... 

While examining the effect of modified catalysts on aldaric acid formation it was found that Pt/C catalysts that were treated with lead salts were extremely selective for the oxidation of the hydroxy group next to the initially formed carboxylic acid to give 2-keto gluconic acid. 2.83 xhese catalysts also promote the selective oxidation of a number of other a-hydroxy acids. For example, lactic acid has been oxidized to pyruvic acid in greater than 95% yield (Eqn. 21.27).83 Similar results have been observed with lead doped Pd/C catalysts. 2,75... 

The well-known naphthoresorcinol color is slowly developed by 2-keto-gluconic acid in a manner resembling galacturonic acid. 

Rhizosphere organisms produce organic acids such as 2-keto-gluconic acid which was suggested to have a chelating action on calcium, thereby improving... 

Gluconic Acid and Keto-Gluconic Acid Production... 

Fujisawa Pharmaceutical (Japan) is a major producer of 2-ketogluconic acid. Its yearly production is about 2,000 tons of 2-keto-gluconic acid, with most of that exported to the United States, Canada, and European countries. 

Diketo-gluconic acid (24) 2-Keto-L-gulonic acid (2-KGA)... 

Oxidation of Isopropylidene Derivatives of Ketose Sugars. Whenever isopropylidene derivatives can be obtained in which all groups except the primary alcoholic grouping at Cl are blocked this method is undoubtedly the best. It may be illustrated by reference to the preparation of 2-keto-D-gluconic acid from D-fructose.14... 

Moreover, the compound (LV) obtained from the reaction of 2-keto-D-gluconic acid with o-phenylenediamine28 has been dehydrated to give a compound which Maurer erroneously described as LYI. In this case, also, the process of dehydration has been shown to be equivalent to that just described for compound L. The product obtained by interaction of 2-furyl-... 

D-arabino-Hexuionic acid ( 2-Keto-D-gluconic acid ) O H H HO hoh2 c—c—c—c—c—c ooh HO HO H red seaweed, Chondrus crispus ( )... 

The preferred method of preparing 74 for laboratory use is by the dehydration of D-xt/lo-5-hexulosonic ( 5-keto-D-gluconic ) acid in refluxing, 5% methanolic hydrogen chloride the crystalline, methyl ester of 74 can then be isolated in 17.4% yield.110 Crystalline 74 is readily prepared from the methyl ester by saponification. Pure 74 has m.p. 200-201° and kmaX = 286 nm (e = 18,000) in water. 

R. Ramage, A. M. MacLeod, and G. W. Rose, Dioxolanes as synthetic intermediates. Part 6. Synthesis of 3-deoxy-D-manno-2-octulosonic acid (KDO), 3-deoxy-D-araMiio-2-heptulosonic acid (DAH) and 2-keto-3-deoxy-D-gluconic acid (KDG), Tetrahedron 47 5625 (1991). 

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