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Isopeptide Method (isopeptide + method)

Distribution by Scientific Domains
Chemistry100%

Kinds of Isopeptide Method

  • acyl isopeptide method
    		•

    Selected Abstracts

    "Click Peptides",Chemical Biology-Oriented Synthesis of Alzheimer's Disease-Related Amyloid , Peptide (A,) Analogues Based on the "O- Acyl Isopeptide Method"

    CHEMBIOCHEM, Issue 10 2006
    Youhei Sohma
    Abstract A clear understanding of the pathological mechanism of amyloid , peptide (A,) 1,42, a currently unexplained process, would be of great significance for the discovery of novel drug targets for Alzheimer's disease (AD) therapy. To date, though, the elucidation of these A,1,42 dynamic events has been a difficult issue because of uncontrolled polymerization, which also poses a significant obstacle in establishing experimental systems with which to clarify the pathological function of A,1,42. We have recently developed chemical biology-oriented pH- or phototriggered "click peptide" isoform precursors of A,1,42, based on the "O -acyl isopeptide method", in which a native amide bond at a hydroxyamino acid residue, such as Ser, is isomerized to an ester bond, the target peptide subsequently being generated by an O,N intramolecular acyl migration reaction. These click peptide precursors did not exhibit any self-assembling character under physiological conditions, thanks to the presence of the one single ester bond, and were able to undergo migration to give the target A,1,42 in a quick and easy, one-way (so-called "click")conversion reaction. The use of click peptides could be a useful strategy to investigate the biological functions of A,1,42 in AD through inducible activation of A,1,42 self-assembly. [source]

    ,O -Acyl isopeptide method' for peptide synthesis: Solvent effects in the synthesis of A,1,42 isopeptide using ,O -acyl isodipeptide unit'

    JOURNAL OF PEPTIDE SCIENCE, Issue 12 2007
    Atsuhiko Taniguchi
    Abstract ,O -Acyl isopeptide method' is an efficient synthetic method for peptides. We designed ,O -acyl isodipeptide units', Boc-Ser/Thr(Fmoc-Xaa)-OH, as important building blocks to enable routine use of the O -acyl isopeptide method. In the synthesis of an A,1,42 isopeptide using O -acyl isodipeptide unit Boc,Ser(Fmoc,Gly),OH, a side reaction, resulting in the deletion of Ser26 in the O -acyl isopeptide structure, was noticed during coupling of the unit. We observed that the side reaction occurred during the activation step and was solvent-dependent. In DMF or NMP, an intramolecular side reaction, originating from the activated species of the unit, occurred during the activation step. In non-polar solvents such as CHCl3 or CH2Cl2, the side reaction was less likely to occur. Using CH2Cl2 as solvent in coupling the unit, the target A,1,42 isopeptide was synthesized with almost no major side reaction. Copyright © 2007 European Peptide Society and John Wiley & Sons, Ltd. [source]

    "Click Peptides",Chemical Biology-Oriented Synthesis of Alzheimer's Disease-Related Amyloid , Peptide (A,) Analogues Based on the "O- Acyl Isopeptide Method"

    CHEMBIOCHEM, Issue 10 2006
    Youhei Sohma
    Abstract A clear understanding of the pathological mechanism of amyloid , peptide (A,) 1,42, a currently unexplained process, would be of great significance for the discovery of novel drug targets for Alzheimer's disease (AD) therapy. To date, though, the elucidation of these A,1,42 dynamic events has been a difficult issue because of uncontrolled polymerization, which also poses a significant obstacle in establishing experimental systems with which to clarify the pathological function of A,1,42. We have recently developed chemical biology-oriented pH- or phototriggered "click peptide" isoform precursors of A,1,42, based on the "O -acyl isopeptide method", in which a native amide bond at a hydroxyamino acid residue, such as Ser, is isomerized to an ester bond, the target peptide subsequently being generated by an O,N intramolecular acyl migration reaction. These click peptide precursors did not exhibit any self-assembling character under physiological conditions, thanks to the presence of the one single ester bond, and were able to undergo migration to give the target A,1,42 in a quick and easy, one-way (so-called "click")conversion reaction. The use of click peptides could be a useful strategy to investigate the biological functions of A,1,42 in AD through inducible activation of A,1,42 self-assembly. [source]

    ,O -Acyl isopeptide method' for peptide synthesis: Solvent effects in the synthesis of A,1,42 isopeptide using ,O -acyl isodipeptide unit'

    JOURNAL OF PEPTIDE SCIENCE, Issue 12 2007
    Atsuhiko Taniguchi
    Abstract ,O -Acyl isopeptide method' is an efficient synthetic method for peptides. We designed ,O -acyl isodipeptide units', Boc-Ser/Thr(Fmoc-Xaa)-OH, as important building blocks to enable routine use of the O -acyl isopeptide method. In the synthesis of an A,1,42 isopeptide using O -acyl isodipeptide unit Boc,Ser(Fmoc,Gly),OH, a side reaction, resulting in the deletion of Ser26 in the O -acyl isopeptide structure, was noticed during coupling of the unit. We observed that the side reaction occurred during the activation step and was solvent-dependent. In DMF or NMP, an intramolecular side reaction, originating from the activated species of the unit, occurred during the activation step. In non-polar solvents such as CHCl3 or CH2Cl2, the side reaction was less likely to occur. Using CH2Cl2 as solvent in coupling the unit, the target A,1,42 isopeptide was synthesized with almost no major side reaction. Copyright © 2007 European Peptide Society and John Wiley & Sons, Ltd. [source]