Gly oxylic Acid

Tryptophan condenses with a-oxo acids at room temperature to yield l,2,3,4-tetrahydro-j8-carboline-l,3-dicarboxylic acids. Both gly-oxylic acid and pyruvic acid yield the expected products. 

H. Laurent-Robert, C. Le Roux, J. Dubac, Enhancement of Dienophilic and Enophilic Readivity of the Gly-oxylic Acid by Bismuthfln) Triflate in the Presence of Water Synlett. 1998,1138-1140. 

Hydroxylamines are usually more accessible than the corresponding nitroso compounds, so only few examples of this reaction have been described in the literature. Aromatic nitroso compounds have been reduced into hydroxylamines with ascorbic acid, gly-oxylic acid and by NADH. It can be safely assumed that any reagent capable of reducing nitro compounds should reduce nitroso compounds as well. 

Meso-tartrate is joined to glucuronic acid in glycosidic linkage and by acetal formation to the aldehyde gly-oxylic acid, HOOC—CHO, which is also joined in an ether linkage to the next repeating unit.130 Similar open acetal linkages join monosaccharide units in some bacterial lipopolysaccharides and may occur more widely.1303... 

AUantoln has been obtained synthetically by heating together gly-oxylic acid and urea. 

The degradation of purines in ammonotelic animals and in some ureo-telic animals proceeds to ammonia and urea, respectively. The oxypurines, hypoxanthine and xanthine, are oxidized to uric acid which is in turn oxidized, under the influence of uricase, to allantoin. Hydrolysis of allantoin proceeds in two stages to yield allantoic acid, and finally urea and gly-oxylic acid. In ammonotelic animals urease cleaves the urea into carbon dioxide and ammonia. 

A rather unusual coupling reaction between HOSu and gly-oxylic acid tosylhydrazone leads to succinimidyl diazoacetate (eq 4) again, the leaving ability of the HOSu residue renders this a useful compound for effecting the direct transfer of a diazoacetyl function to amines, phenols, and peptides. " ... 

There are some classes of compounds present in seawater which have known biological activity but have received little attention. Compounds involved in chemical communication, especially halogenated compounds, will be discussed in other chapters. Other compounds of interest are those involved in the citric acid cycle, the major pathway of metabolism in almost all cells. Citric acid cycle intermediates and reactions are involved in the biosynthesis of most of the major metabolites, from amino acids and carbohydrates to long-chain fatty acids and porphyrins (Mahler and Cordes, 1971). The intermediates, such as succinic, fumaric, malic, oxaloacetic, citric, gly-oxylic, and oxoglutaric acids are present in almost all organisms and are certainly being produced in the sea. 

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