14β-Hydroxybaccatin III, a compound with limited availability by natural sources, is the starting material for the synthesis of the second-generation anticancer taxoid ortataxel. The 7-tert-butoxycarbonyl (1a) and 7-triethylsilyl (1b) derivatives of 14β-hydroxybaccatin III 1,14-carbonate were synthesized from 10-deacetylbaccatin III (3). The crucial steps were (a) the C14β hydroxylation of the corresponding 13-oxobaccatin III derivatives by oxaziridine-mediated electrophilic oxidation and (b) the reduction of the C13 carbonyl group with sodium or alkylammonium borohydrides. This protocol provides a practical way for the semisynthesis of ortataxel from 10-deacetylbaccatin III, a compound readily available from various yews.
|Titolo:||Diastereoselective 14β-Hydroxylation of Baccatin III Derivatives|
|Settore Scientifico Disciplinare:||Settore CHIM/06 - Chimica Organica|
|Data di pubblicazione:||2003|
|Digital Object Identifier (DOI):||10.1021/jo0347112|
|Appare nelle tipologie:||01 - Articolo su periodico|