Multifunctional catalysis for transamination reaction of ?-amino acids with glyoxylic acid in synthetic bilayer memberane

α-Methyl-DL-tryptophan, injected intraperitoneally into rats, has a weight-depressing action lasting up to 72 hours. Dosages in the range 0.015–2.0 millimoles/kg body weight (3.3–436 mg/kg) are effective. Attempts to antagonize the weight-depressing action by giving essential amino acids and B vitamins were unsuccessful. Metabolic studies have shown that about half the injected dose of the compound (or its derivatives), as measured by the Hopkins–Cole glyoxylic acid reaction, is excreted in the urine in 24 hours; most of this appears during the first 4 hours after the injection. Ina search for an explanation for the weight-depressing action of α-methyltryptophan, tryptophan pyrrolase activity in the liver was estimated. This enzymic activity increases for 8 hours after the injection of α-methyltryptophan, and thereafter remains high for 72 hours. Tryptophan-injected animals showed increases in tryptophan pyrrolase level for 1.5 hours, and a return to normal concentrations within 24 hours. Other α-methyl amino acids which were tested had no comparable effect on body weight.

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Direct synthesis of unprotected α-amino acids via allylation of hydroxyglycine

Canadian Journal of Chemistry ◽

10.1139/v05-096 ◽

2005 ◽

Vol 83 (6-7) ◽

pp. 937-942 ◽

Cited By ~ 15

Author(s):

Masaharu Sugiura ◽

Chieko Mori ◽

Keiichi Hirano ◽

Shū Kobayashi

Keyword(s):

Amino Acids ◽

Direct Synthesis ◽

Glyoxylic Acid ◽

Cope Rearrangement ◽

Reaction Conditions ◽

Stereoselective Reactions ◽

High Stereoselectivity

Hydroxyglycine, the ammonia adduct of glyoxylic acid, was found to react with various allylboronates in the presence of triethylamine in methanol to give unprotected α-amino acids directly with high stereoselectivity. For instance, the reactions with (E)- and (Z)-crotylboronates afforded the corresponding anti- and syn-crotylated products (isoleucine and alloisoleucine after hydrogenation) with high diastereoselectivity, respectively. Interestingly, it was found that isomerization of the products (γ-adducts to α-adducts) occurred under the reaction conditions in some cases. Control experiments have suggested that the isomerization took place via 2-aza (or azonia) Cope rearrangement of imines derived from γ-adducts and glyoxylic acid.Key words: hydroxyglycine, glyoxylic acid, allylboronates, α-amino acids, allylglycines, isoleucine, alloisoleucine, stereoselective reactions, isomerization, 2-aza (azonia) Cope rearrangement.

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Studies of the pathway of HCN formation from glycine in a psychrophilic basidiomycete

Canadian Journal of Botany ◽

10.1139/b77-232 ◽

1977 ◽

Vol 55 (15) ◽

pp. 2065-2069 ◽

Cited By ~ 11

Author(s):

E. W. B. Ward ◽

A. N. Starratt ◽

J. R. Robinson

Keyword(s):

Amino Acids ◽

Aspartic Acid ◽

Glyoxylic Acid

Eleven [14C]-labeled amino acids were tested for their ability to serve as precursors of HCN in cultures of a psychrophilic basidiomycete. Only glycine and, to a much lesser degree, L-serine and L-aspartic acid were effective. By using [2-14C, 15N]glycine, it was demonstrated that the C–N bond remains intact during the conversion to HCN. No evidence was obtained for the participation of N-hydroxyglycine or glyoxylic acid oxime as intermediates in the pathway of HCN formation.

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Synthesis of Fmoc-protected aza-β3-amino acids via reductive amination of glyoxylic acid

Tetrahedron Letters ◽

10.1016/j.tetlet.2005.07.160 ◽

2005 ◽

Vol 46 (41) ◽

pp. 7073-7075 ◽

Cited By ~ 14

Author(s):

Olivier Busnel ◽

Lanrong Bi ◽

Michèle Baudy-Floc’h

Keyword(s):

Amino Acids ◽

Reductive Amination ◽

Glyoxylic Acid

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OBSERVATIONS ON THE ENZYMATIC DEGRADATION AND CONVERSION OF CERTAIN L- AND D-AMINO ACIDS BY AN EFFECTIVE STRAIN OF RHIZOBIUM MELILOTI

Canadian Journal of Microbiology ◽

10.1139/m55-088 ◽

1955 ◽

Vol 1 (9) ◽

pp. 743-748 ◽

Cited By ~ 5

Author(s):

D. C. Jordan

Keyword(s):

Amino Acids ◽

Glutamic Acid ◽

Aspartic Acid ◽

Rhizobium Meliloti ◽

Effective Strain ◽

Glyoxylic Acid ◽

Amino Group ◽

Intact Cells ◽

Ammonia Recovery ◽

Probable Occurrence

Washed intact cells of an effective strain of Rhizobium meliloti oxidatively deaminated glycine and the L- and D-isomers of a number of amino acids. The interpretation of the data concerning ammonia recovery was complicated, however, by the probable occurrence of transamination and assimilation. Glyoxylic acid, produced by removal of the glycine amino group, was isolated as the corresponding dinitrophenylhydrazone. No anaerobic decarboxylation of glutamic acid or histidine was observed. Cell-free extracts synthesized glutamic acid from α-ketoglutaric acid when glycine, L-histidine, D-aspartic acid, or D-valine acted as amino-group donors. In addition, acetone-dried cells formed alanine from D-aspartic acid and pyruvate. Alanine racemase activity was detected in cell-free extracts and acetone-dried cells, but racemization of aspartic or glutamic acids did not occur. L-glutamic acid, formed by cell-free extracts in mixtures containing D-aspartic and α-ketoglutaric acids, may have been produced by a series of three coupled reactions involving racemization and L-and D-amino acid transamination.

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