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Related Concept Videos

Nuclear Transmutation03:20

Nuclear Transmutation

Nuclear transmutation is the conversion of one nuclide into another. It can occur by the radioactive decay of a nucleus, or the reaction of a nucleus with another particle. The first manmade nucleus was produced in Ernest Rutherford’s laboratory in 1919 by a transmutation reaction, the bombardment of one type of nuclei with other nuclei or with neutrons. Rutherford bombarded nitrogen-14 atoms with high-speed α particles from a natural radioactive isotope of radium and observed protons being...
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The coupling interactions of nuclei across four or more bonds are usually weak, with J values less than 1 Hz. While these are usually not observed in spectra, the presence of multiple bonds along the coupling pathway can result in observable long-range coupling.
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Spin–Spin Coupling: Three-Bond Coupling (Vicinal Coupling)01:22

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Mizoroki-Heck Cross-coupling Reactions Catalyzed by Dichloro{bis[1,1',1''-(phosphinetriyl)tripiperidine]}palladium Under Mild Reaction Conditions
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Mizoroki-Heck Cross-coupling Reactions Catalyzed by Dichloro{bis[1,1',1''-(phosphinetriyl)tripiperidine]}palladium Under Mild Reaction Conditions

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COMU: a third generation of uronium-type coupling reagents.

Ayman El-Faham1, Fernando Albericio

  • 1Institute for Research in Biomedicine, Barcelona Science Park, Baldiri Reixac 10, 08028-Barcelona, Spain. aymanel_faham@hotmail.com

Journal of Peptide Science : an Official Publication of the European Peptide Society
|December 2, 2009
PubMed
Summary
This summary is machine-generated.

COMU, a novel uronium-type coupling reagent, offers enhanced solubility, stability, and reactivity. Its water-soluble by-products and safer profile make it ideal for peptide synthesis.

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Mizoroki-Heck Cross-coupling Reactions Catalyzed by Dichloro{bis[1,1',1''-(phosphinetriyl)tripiperidine]}palladium Under Mild Reaction Conditions
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Area of Science:

  • Organic Chemistry
  • Peptide Synthesis
  • Chemical Reagents

Background:

  • Uronium-type coupling reagents are essential in peptide synthesis.
  • Existing reagents like HATU and HBTU have safety concerns, including explosion risks and allergic reactions.
  • There is a need for safer and more efficient coupling reagents.

Purpose of the Study:

  • To introduce and characterize COMU, a new generation uronium-type coupling reagent.
  • To evaluate the performance and safety profile of COMU in peptide synthesis.
  • To compare COMU with traditional benzotriazole-based coupling reagents.

Main Methods:

  • COMU synthesis utilizing ethyl 2-cyano-2-(hydroxyimino)acetate (Oxyma) and a morpholino carbon skeleton.
  • Evaluation of COMU's solubility, stability, and reactivity.
  • Assessment of COMU's performance in solution-phase peptide synthesis with varying base equivalents.
  • Comparative safety analysis against HATU and HBTU.

Main Results:

  • COMU exhibits improved solubility, stability, and reactivity due to its morpholino group.
  • Effective coupling achieved with only 1 equivalent of base, highlighting the role of the hydrogen bond acceptor.
  • Water-soluble by-products facilitate easy removal, simplifying purification.
  • COMU demonstrates a significantly better safety profile, with reduced risk of explosion and allergic reactions compared to benzotriazole-based reagents.

Conclusions:

  • COMU is a highly effective and safe uronium-type coupling reagent for solution-phase peptide synthesis.
  • Its unique structure provides advantages in terms of reactivity, purification, and safety.
  • COMU represents a valuable advancement over conventional coupling reagents, offering a reduced hazard profile.