Glutamic acid, Hydroxy

Lactone 6.209 (a-carboxy-y-butyrolactone) is an interesting and useful synthetic intermediate. 22 Lactone 6.209 is readily converted to 2-hydroxy glutamic acid 6.210) and then treated with NOCl to give 2-hydroxy-4-aminobutanoic acid... 

Neither glutamic acid nor hydroxy-glutamic acid has been found essential in nutrition although the former is a component of an... 

Both glutamic acid and hydroxy-glutamic acid are glucogenic in the diabetic animal, three of the five carbon atoms being used for glucose formation, probably by way of a-keto glutaric acid. 

An estimation of the amount of amino acid production and the production methods are shown ia Table 11. About 340,000 t/yr of L-glutamic acid, principally as its monosodium salt, are manufactured ia the world, about 85% ia the Asian area. The demand for DL-methionine and L-lysiae as feed supplements varies considerably depending on such factors as the soybean harvest ia the United States and the anchovy catch ia Pern. Because of the actions of D-amiao acid oxidase and i.-amino acid transamiaase ia the animal body (156), the D-form of methionine is as equally nutritive as the L-form, so that DL-methionine which is iaexpensively produced by chemical synthesis is primarily used as a feed supplement. In the United States the methionine hydroxy analogue is partially used ia place of methionine. The consumption of L-lysiae has iacreased ia recent years. The world consumption tripled from 35,000 t ia 1982 to 100,000 t ia 1987 (214). Current world consumption of L-tryptophan and i.-threonine are several tens to hundreds of tons. The demand for L-phenylalanine as the raw material for the synthesis of aspartame has been increasing markedly. 

In E. coli GTP cyclohydrolase catalyzes the conversion of GTP (33) into 7,8-dihydroneoptetin triphosphate (34) via a three-step sequence. Hydrolysis of the triphosphate group of (34) is achieved by a nonspecific pyrophosphatase to afford dihydroneopterin (35) (65). The free alcohol (36) is obtained by the removal of residual phosphate by an unknown phosphomonoesterase. The dihydroneoptetin undergoes a retro-aldol reaction with the elimination of a hydroxy acetaldehyde moiety. Addition of a pyrophosphate group affords hydroxymethyl-7,8-dihydroptetin pyrophosphate (37). Dihydropteroate synthase catalyzes the condensation of hydroxymethyl-7,8-dihydropteroate pyrophosphate with PABA to furnish 7,8-dihydropteroate (38). Finally, L-glutamic acid is condensed with 7,8-dihydropteroate in the presence of dihydrofolate synthetase. 

Oxazolidines are prepared to allow selective protection of the a- or co-COjU groups in aspartic and glutamic acids and a-hydroxy acids. 

Ward and Mason157) explain these effects by direct hydrogen bonds between the hydroxy group of hydroxyproline in position 3 and the carboxylic side chain of glutamic acid in the adjacent chains. From the sequence we know that in the case of parallel and... 

Tartaric acid HOOC(CHOH)2COOH 2 2 4 Gallic acid HOOCC6H2(OH)3 3 1 4 Hydroxy glutamic HOOCCH2CH(OH)CH-acid (NH2)COOH 12 14 Introduction... 

Takeuchi, H., et al., Elfects of alpha-kainic acid, domoic acid and their derivatives on a molluscan giant neuron sensitive to beta-hydroxy-L-glutamic acid, Eur. J. Pharmacol, 102, 2, 325, 1984. 

A substituted acetamidomalonic ester, tetraethyl 1 -acetamido-4-hydroxy-butane-l,l,3,3-tetracarboxylate, was used in the preparation of cis- and frans-pyrrolidine-2,4-dicarboxylic acids, cyclic analogs of glutamic acid (91TL3049). 

Stereoselective alkylation with aliphatic bromides and iodides of the Schiff bases of tert-butyl glycinate with (—)-(15,25,55)-2-hydroxypinan-3-one or (+)-(lR,2R,5R)-2-hydroxy-pinan-3-one 150 was reported to produce lipidated amino acids as d- and L-enantiomers in 80 to over 90% ee. 151 Similarly, the asymmetric synthesis of a derivative of arachidonic acid (4) has also been reported. The pure enantiomer was obtained via regioselective functionalization of a chirally pure glutamic acid. 152 ... 

The direction of enantio-differentiation (the predominant enantiomer R or S, to be produced) is decided by two factors. One factor is the configuration of the chiral structure, that is, if the catalyst modified with (S)-glutamic acid [(S)-Glu-MRNi] produces (R)-MHB from MAA, then (R)-Glu-MRNi produces (S)-MHB (2). The other factor is the nature of X. That is, when the amino acid or hydroxy acid with the same configuration is used as the modifying reagent, the configurations of the predominant products are enantiomers of each other in most cases. For example, (S)-aspartic acid-MRNi produces (R)-MHB and (S)-malic acid-MRNi produces (S)-MHB (19). 

These also presumably lead to a transient quinonoid-carbanionic intermediate. Addition of a proton at the original site of decarboxylation followed by breakup of the Schiff base completes the sequence. Decarboxylation of amino acids is nearly irreversible and frequently appears as a final step in synthesis of amino compounds. For example, in the brain glutamic acid is decarboxy-lated to y-aminobutyric acid (Gaba),193 196b while 3,4-dihydroxyphenylalanine (dopa) and 5-hydroxy-... 

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