Results 171 to 180 of about 1,982 (213)

Regarding 4-pyridoxic acid-5′-phosphate in animal tissue

Biochemical and Biophysical Research Communications, 1972
Abstract To test recent claims that 4-pyridoxic acid-5′-phosphate (PICP) is a previously undetected, major metabolite of vitamin B 6 in animals (up to 20% of the total vitamin B 6 in liver), we analyzed mouse and rat liver for vitamin B 6 metabolites after injection of 3 H-pyridoxine.
K T, Wei, R R, Bell, B E, Haskell
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Validated UPLC-MS/MS method for the analysis of vitamin B6 pyridoxal 5́-phosphate, pyridoxal, pyridoxine, pyridoxamine, and pyridoxic acid in human cerebrospinal fluid

Journal of Chromatography B, 2022
Vitamin B6 and its metabolites play a crucial role in the development and interaction of brain metabolism. Following diagnostic improvements additional inherited disorders in vitamin B6 metabolism have been identified, most of them leading to a severe epileptic disorder accompanied by progressive neurological deficits including intellectual disability ...
Julia, Rossmann, Stine, Christ, Sylvia, Richter, Sven, Friedrich Garbade, Georg, Friedrich Hoffmann, Thomas, Opladen, Jürgen, Günther Okun   +6 more
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Pyridoxal phosphate. 5. 2-Formylethynylphosphonic acid and 2-formylethylphosphonic acid, potent inhibitors of pyridoxal phosphate binding and probes of enzyme topography

Journal of Medicinal Chemistry, 1976
The title compounds (17 and 21) were prepared in good yield by synthesis of the phosphonate diester acetals (14 and 19), deesterification with chloro- or bromotrimethylsilane, hydrolysis of the acetal group, and formation of the characterized barium salts.
A J, Rudinskas, T L, Hullar
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Assay of pyridoxal-5'-phosphate, pyridoxal and pyridoxic acid in biological material.

International journal for vitamin and nutrition research. Internationale Zeitschrift fur Vitamin- und Ernahrungsforschung. Journal international de vitaminologie et de nutrition, 1990
The two vitamin B6-vitamers having an aldehyde function are oxidised to the corresponding acids and subjected to an HPLC separation on an RP 18 phase with a solvent consisting of 5% methanol in phosphate buffer at pH 3.5. The detection is carried out by fluorometry with excitation at 318 nm and emission at 418 nm.
D, Hess, J P, Vuilleumier
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Conformational analysis of pyridoxal amino acid schiff's bases

International Journal of Quantum Chemistry, 2009
The conformational properties of a series of pyridoxal amino acid Schiff's bases have been calculated. The calculations were performed using the program CAMSEQ which employs a set of empirical potential energy functions. The cndo/2 charge distributions are also given in this preliminary report.
H. J. R. Weintraub, M.-D. Tsai, S. R. Byrn, C.-J. Chang, H. G. Floss   +4 more
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Chiral Pyridoxal-Catalyzed Asymmetric Biomimetic Transamination of α-Keto Acids

Organic Letters, 2015
A series of chiral pyridoxals 8 and 9 have been developed from commercially available pyridoxine and (S)-α,α-diarylprolinols. The pyridoxals exhibited good catalytic activity in an asymmetric transamination of α-keto acids with 2,2-diphenylglycine (7f) as the amine source to give various α-amino acids in 29-85% yields with 53-80% ee's.
Limin, Shi, Chuangan, Tao, Qin, Yang, Yong Ethan, Liu, Jing, Chen, Jianfeng, Chen, Jiaxin, Tian, Feng, Liu, Bo, Li, Yongling, Du, Baoguo, Zhao   +10 more
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Simplifying Pyridoxal: Practical Methods for Amino Acid Dynamic Kinetic Resolution

Organic Letters, 2010
Metal complexes of picolinaldehyde are identified as low-cost and environmentally benign catalysts, providing high reaction rates and turnovers for the racemization of amino acids. These pyridoxal surrogates demonstrate activity toward a variety of amino acid esters.
Albert E, Felten, Gangguo, Zhu, Zachary D, Aron   +2 more
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A simple, sensitive and reproducible assay for pyridoxal 5′-phosphate and 4-pyridoxic acid in human plasma

Clinica Chimica Acta, 1999
We describe a procedure for the measurement of pyridoxal 5'-phosphate and of 4-pyridoxic acid in human plasma samples. It is based on the conversion of pyridoxal 5'-phosphate to 4-pyridoxic acid 5'-phosphate by cyanide in alkaline medium, followed by a high pressure liquid chromatographic separation, with fluorescence detection at acid pH. The assay is
C J, Bates, K D, Pentieva, N, Matthews, A, Macdonald   +3 more
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ChemInform Abstract: CATALYTIC ACTIVITIES OF PYRIDOXAL ANALOGUES PART 1, THE CATALYTIC EFFECTS OF PYRIDOXAL, PYRIDOXAL METHOCHLORIDE, AND PYRIDOXAL N‐OXIDE ON THE RACEMIZATION OF L‐GLUTAMIC ACID

Chemischer Informationsdienst, 1975
AbstractIn einer verbesserten Synthese werden ausgehend von Pyridoxal ‐ HCl (I) a) über die Stufen (II) und (III), das Methochlorid (IV) bzw. b) über die Stufen (II) und (V) das N‐Oxid (VI) dargestellt.
MAKOTO ANDO, SAKAE EMOTO
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Enantiomer Synthesis of Amino Acids with Pyridoxal Enzymes

1987
We here describe recent developments in the enzymatic synthesis of various optically active amino acids with pyridoxal enzymes including L-methionine γ-lyase, 0-acety1-homoserine (thiol)-lyase, D-amino acid aminotransferase, D-cysteine desulfhydrase, cystathionine γ-lyase, tryptophan synthase and amino acid racemases.
K. Soda, K. Tanizawa, N. Esaki, H. Tanaka   +3 more
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