Activity difference between alpha-COOH and beta-COOH in N-phosphorylaspartic acids.

Zhong-Zhou Chen; Bo Tan; Yan-Mei Li; Yu-Fen Zhao; Yu-Feng Tong; Jin-Feng Wang

doi:10.1021/jo0300082

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PubMed · 12737590

Activity difference between alpha-COOH and beta-COOH in N-phosphorylaspartic acids.

Zhong-Zhou Chen·Bo Tan·Yan-Mei Li·Yu-Fen Zhao·Yu-Feng Tong·Jin-Feng Wang

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Abstract

N-phosphorylamino acids are chemically active species that have many biomimic activities. alpha-COOH in amino acids and peptides behaviors rather differently than beta-COOH in many biochemical processes and takes a more important role in the origin of life. Activity differences between alpha-COOH and beta-COOH in the peptide formation of phosphoryl amino acids are studied by 1D, 2D NMR techniques and by ab initio and density functional theory (DFT) calculations in this paper. Phosphoryl dipeptide is formed directly from phosphoryl aspartic acids without any coupling reagents. Only the alpha-dipeptide ester is observed by 1D (1)H, (13)C, and (31)P NMR and 2D NMR. In the ab initio and DFT calculations, the pentacoordinate phosphorane intermediates containing five-membered rings are predicted to be more favored than those with six-membered rings. Both the experimental results and the theoretical calculations suggest that only the alpha-COOH group is activated by N-phosphorylation in N-phosphorylaspartic acid under mild conditions.

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Aspartic Acid Kinetics Models, Theoretical Molecular Conformation Molecular Mimicry Molecular Structure Nuclear Magnetic Resonance, Biomolecular Organophosphorus Compounds Peptides Stereoisomerism Structure-Activity Relationship Comparative Study Journal Article Research Support, Non-U.S. Gov't

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Zhong-Zhou Chen, Bo Tan, Yan-Mei Li, Yu-Fen Zhao, Yu-Feng Tong, Jin-Feng Wang. 2003-05-16. Activity difference between alpha-COOH and beta-COOH in N-phosphorylaspartic acids.. https://doi.org/10.1021/jo0300082

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