Differentially-protected steroidal triamines; scaffolds with potential for medicinal, supramolecular, and combinatorial chemistry

Org Biomol Chem. 2004 Nov 21;2(22):3320-8. doi: 10.1039/B412298D. Epub 2004 Oct 15.

Abstract

Cholic acid 2a has been converted into two new orthogonally-protected triamino scaffolds, 13 and 14. The synthesis proceeds via the bis-Boc-NH-substituted azide 10, for which an improved preparation is described. After removal of the Boc groups, the two axial amines are differentiated through a novel monoprotection employing 1-(2-nitrobenzenesulfonyloxy)-benzotriazole 29. Regioselectivity of > or 50 : 1 is achieved, presumably reflecting an exceptional sensitivity to steric hindrance. Protection of the remaining amino group as Boc or Alloc gives the scaffolds in approximately 40% overall yield from cholic acid. Scaffold 13 has been sequentially deprotected and derivatised with N-carbamoyl amino acids, to give a model for tripodal peptide libraries.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Amino Acids / chemistry
  • Azides / chemistry
  • Chemistry, Organic / methods*
  • Cholic Acid / chemistry*
  • Combinatorial Chemistry Techniques
  • Molecular Structure
  • Polyamines / chemical synthesis*
  • Polyamines / chemistry
  • Stereoisomerism

Substances

  • Amino Acids
  • Azides
  • Polyamines
  • Cholic Acid