Differentially-protected steroidal triamines; scaffolds with potential for medicinal, supramolecular, and combinatorial chemistry
作者:Vicente del Amo、Laura Siracusa、Theodoros Markidis、Beatriz Baragaña、Khadga M. Bhattarai、Marta Galobardes、Gregorio Naredo、M. Nieves Pérez-Payán、Anthony P. Davis
DOI:10.1039/b412298d
日期:——
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