An efficient synthesis of 3-aza-steroids bearing a pyridine as an A ring was achieved via intramolecular cycloaddition of orthoquinodimethanes, which were generated from a 3-azabicyclo[4.2.0]octa-l,3,5-trien-7-one ketal.
Synthesis and characterization of (±)-13-hydroxy-3,11-diaza steroids
作者:Malika Ibrahim-Ouali、Eugénie Romero
DOI:10.1016/j.steroids.2011.11.003
日期:2012.1
An efficient strategy for introducing a nitrogen atom in positions 3 and 11 of the steroidal skeleton, which are key positions for biological purposes, is described. This procedure involves an intramolecular Diels-Alder cycloaddition of o-quinodimethanes which are generated from a 3-azabicyclo[4.2.0]octa-1,3,5-trien-7-one. The characteristic H-1 and C-13 NMR spectroscopic features of the synthesized compounds are reported. (C) 2011 Elsevier Inc. All rights reserved.
First total synthesis of (±)-3-aza-11-oxa-1,3,5(10)-trieno steroids
We set out to describe a new and versatile method for preparing 3-aza-11-oxa-1,3,5(10)-trieno steroids via an intramolecular Diels-Alder cycloaddition of o-quinodimethanes as the key step. The characteristic H-1 and C-13 NMR spectroscopic features of the synthesized compounds are reported. (c) 2006 Elsevier Inc. All rights reserved.