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 ≥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 ∼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.
| Original language | English |
|---|---|
| Pages (from-to) | 3320-3328 |
| Number of pages | 9 |
| Journal | Organic and Biomolecular Chemistry |
| Volume | 2 |
| Issue number | 22 |
| DOIs | |
| Publication status | Published - 15 Oct 2004 |
ASJC Scopus subject areas
- Biochemistry
- Physical and Theoretical Chemistry
- Organic Chemistry