1,4-disubstituted-[1,2,3]triazolyl-containing analogues of MT-II: design, synthesis, conformational analysis, and biological activity

J Med Chem. 2014 Nov 26;57(22):9424-34. doi: 10.1021/jm501027w. Epub 2014 Nov 13.

Abstract

Side chain-to-side chain cyclizations represent a strategy to select a family of bioactive conformations by reducing the entropy and enhancing the stabilization of functional ligand-induced receptor conformations. This structural manipulation contributes to increased target specificity, enhanced biological potency, improved pharmacokinetic properties, increased functional potency, and lowered metabolic susceptibility. The Cu(I)-catalyzed azide-alkyne 1,3-dipolar Huisgen's cycloaddition, the prototypic click reaction, presents a promising opportunity to develop a new paradigm for an orthogonal bioorganic and intramolecular side chain-to-side chain cyclization. In fact, the proteolytic stable 1,4- or 4,1-disubstituted [1,2,3]triazolyl moiety is isosteric with the peptide bond and can function as a surrogate of the classical side chain-to-side chain lactam forming bridge. Herein we report the design, synthesis, conformational analysis, and functional biological activity of a series of i-to-i+5 1,4- and 4,1-disubstituted [1,2,3]triazole-bridged cyclopeptides derived from MT-II, the homodetic Asp(5) to Lys(10) side chain-to-side chain bridged heptapeptide, an extensively studied agonist of melanocortin receptors.

Publication types

  • Research Support, N.I.H., Extramural

MeSH terms

  • Azides / chemistry
  • Chemistry, Pharmaceutical / methods*
  • Copper / chemistry
  • Drug Design
  • HEK293 Cells
  • Humans
  • Lactams / chemistry*
  • Ligands
  • Linear Models
  • Magnetic Resonance Spectroscopy / methods
  • Metallothionein / chemistry*
  • Molecular Conformation
  • Peptides / chemistry
  • Receptors, Melanocortin / agonists
  • Structure-Activity Relationship
  • Triazoles / chemistry*

Substances

  • Azides
  • Lactams
  • Ligands
  • Peptides
  • Receptors, Melanocortin
  • Triazoles
  • Copper
  • Metallothionein