scholarly journals Amino acid functionalisation using the 2-phosphaethynolate anion. A facile route to (phosphanyl)carbonyl-amino acids

2017 ◽  
Vol 53 (52) ◽  
pp. 7092-7095 ◽  
Author(s):  
E. N. Faria ◽  
A. R. Jupp ◽  
J. M. Goicoechea
Keyword(s):  
Amino Acids ◽  
Amino Acid ◽  
Enantiomerically Pure ◽  
Facile Route

We describe the reactivity of the 2-phosphaethynolate anion (PCO−) towards enantiomerically pure α-amino acids (AAs) resulting in the formation of novel salts of phosphinecarboxamides bearing chiral functionalities.

N-Methylamino acids in peptide synthesis. V. The synthesis of N-tert-butyloxycarbonyl, N-methylamino acids by N-methylation

1977 ◽  
Vol 55 (5) ◽  
pp. 906-910 ◽  
Author(s):  
S. T. Cheung ◽  
N. Leo Benoiton
Keyword(s):  
Amino Acids ◽  
Amino Acid ◽  
Methyl Iodide ◽  
Peptide Synthesis ◽  
Room Temperature ◽  
Sodium Hydride ◽  
Amino Acid Derivatives ◽  
Enantiomerically Pure ◽  
Neutral Amino Acids ◽  
Related Data

The preparation of enantiomerically pure N-tert-butyloxycarbonyl,N-methylamino acids by N-methylation of the parent amino acid derivatives using sodium hydride and methyl iodide in tetrahydrofuran at room temperature is described for neutral amino acids including O-benzyl-protected threonine and tyrosine. Methylation of the O-benzylserine derivative under these conditions gives the N-methyldehydroalanine derivative. The β-elimination is completely suppressed, giving the corresponding N-methylserine derivative when the reaction is carried out at 5 °C. Other related data on N-methylation and N-methylamino acid derivatives are presented.

Stereoselective Reaction Mass Spectrometry with Cyclic α-Amino Acids

1991 ◽  
Vol 46 (3) ◽  
pp. 320-325 ◽  
Author(s):  
Jürgen Martens ◽  
Stefan Lübben ◽  
Walter Schwarting
Keyword(s):  
Mass Spectrometry ◽  
Amino Acids ◽  
Amino Acid ◽  
Absolute Configuration ◽  
Mass Spectra ◽  
Reaction Mass ◽  
Chiral Selector ◽  
Enantiomerically Pure ◽  
Stereoselective Reaction ◽  
The Absolute

Stereoselective reaction mass spectrometry in the chemical ionization (isobutane) mode has been used to detect the absolute configuration of enantiomerically pure cyclic α-amino acids. Thus, an enantiomerically pure cyclic α-amino acid was allowed to react on a micromole level with both enantiomers of a chiral selector and the mass spectra were detected. The relative abundances of characteristic ions formed by the diastereoselective reaction between the α-amino acid and the chiral selector of the same configuration were much higher than those ions formed by the α-amino acid and the chiral selector of a different configuration. The absolute configuration of the α-amino acid may be predicted by careful examination of the two stereoselective reaction mass spectra of the α-amino acid measured with both, the chiral (R)-and (S)-selector respectively. Various (R)- and (S)-carboxylic acids and (R)- and (S)-α-phenylethyl amine have been used as chiral selectors.

Dietary intake of tryptophan tied emotion-related impulsivity in humans

2019 ◽  
pp. 1-8 ◽  
Author(s):  
Florian Javelle ◽  
Descartes Li ◽  
Philipp Zimmer ◽  
Sheri L. Johnson
Keyword(s):  
Amino Acids ◽  
Amino Acid ◽  
Food Intake ◽  
Essential Amino Acid ◽  
Food Habits ◽  
Psychological Disorder ◽  
Serotonin Synthesis ◽  
Amino Acid Tryptophan ◽  
Pass Through ◽  
Three Factor

Abstract. Emotion-related impulsivity, defined as the tendency to say or do things that one later regret during periods of heightened emotion, has been tied to a broad range of psychopathologies. Previous work has suggested that emotion-related impulsivity is tied to an impaired function of the serotonergic system. Central serotonin synthesis relies on the intake of the essential amino acid, tryptophan and its ability to pass through the blood brain barrier. Objective: The aim of this study was to determine the association between emotion-related impulsivity and tryptophan intake. Methods: Undergraduate participants (N = 25, 16 women, 9 men) completed a self-rated measure of impulsivity (Three Factor Impulsivity Index, TFI) and daily logs of their food intake and exercise. These data were coded using the software NutriNote to evaluate intakes of tryptophan, large neutral amino acids, vitamins B6/B12, and exercise. Results: Correlational analyses indicated that higher tryptophan intake was associated with significantly lower scores on two out of three subscales of the TFI, Pervasive Influence of Feelings scores r =  –.502, p < . 010, and (lack-of) Follow-Through scores, r =  –.407, p < . 050. Conclusion: Findings provide further evidence that emotion-related impulsivity is correlated to serotonergic indices, even when considering only food habits. It also suggests the need for more research on whether tryptophan supplements might be beneficial for impulsive persons suffering from a psychological disorder.

Purification of Antihemophilic Factor (Factor VIII) by Amino Acid Precipitation*

1964 ◽  
Vol 11 (01) ◽  
pp. 064-074 ◽  
Author(s):  
Robert H Wagner ◽  
William D McLester ◽  
Marion Smith ◽  
K. M Brinkhous
Keyword(s):  
Amino Acids ◽  
Amino Acid ◽  
Factor Viii ◽  
Plasma Protein ◽  
Acid Precipitation ◽  
Aminobutyric Acid ◽  
Gamma Aminobutyric Acid ◽  
Specific Procedure ◽  
Beta Alanine ◽  
Antihemophilic Factor

Summary1. The use of several amino acids, glycine, alpha-aminobutyric acid, alanine, beta-alanine, and gamma-aminobutyric acid, as plasma protein precipitants is described.2. A specific procedure is detailed for the preparation of canine antihemophilic factor (AHF, Factor VIII) in which glycine, beta-alanine, and gammaaminobutyric acid serve as the protein precipitants.3. Preliminary results are reported for the precipitation of bovine and human AHF with amino acids.

Complete Covalent Structure of Human Platelet Factor 4

1979 ◽  
Vol 42 (05) ◽  
pp. 1652-1660 ◽  
Author(s):  
Francis J Morgan ◽  
Geoffrey S Begg ◽  
Colin N Chesterman
Keyword(s):  
Amino Acids ◽  
Molecular Weight ◽  
Amino Acid ◽  
Amino Acid Sequence ◽  
Human Platelet ◽  
Platelet Factor 4 ◽  
Platelet Factor ◽  
Disulphide Bonds ◽  
Covalent Structure

SummaryThe amino acid sequence of the subunit of human platelet factor 4 has been determined. Human platelet factor 4 consists of identical subunits containing 70 amino acids, each with a molecular weight of 7,756. The molecule contains no methionine, phenylalanine or tryptophan. The proposed amino acid sequence of PF4 is: Glu-Ala-Glu-Glu-Asp-Gly-Asp-Leu-Gln-Cys-Leu-Cys-Val-Lys-Thr-Thr-Ser- Gln-Val-Arg-Pro-Arg-His-Ile-Thr-Ser-Leu-Glu-Val-Ile-Lys-Ala-Gly-Pro-His-Cys-Pro-Thr-Ala-Gin- Leu-Ile-Ala-Thr-Leu-Lys-Asn-Gly-Arg-Lys-Ile-Cys-Leu-Asp-Leu-Gln-Ala-Pro-Leu-Tyr-Lys-Lys- Ile-Ile-Lys-Lys-Leu-Leu-Glu-Ser. From consideration of the homology with p-thromboglobulin, disulphide bonds between residues 10 and 36 and between residues 12 and 52 can be inferred.

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