On the Construction of the C/D-Ring Systems of Aphidicolin and Stemodin: a Regio- and Stereospecific Synthesis of 17-Noraphidicolaii-16 one and 17-Norstemodan-16-one Preliminary Communication
A very simple regio- and stereospecific synthesis of 17-noraphidicolan-16-one and 17-norstemodan-16-one by solvolytic rearrangement of suitable bicyclo[2.2.2]--octenyl methanesulfonate is described.
Diastereoselective Total Synthesis of (+)-13-Stemarene by Fourth Generation Methods: A Formal Total Synthesis of (+)-18-Deoxystemarin
作者:Francesca Leonelli、Federico Blesi、Paolo Dirito、Andrea Trombetta、Francesca Ceccacci、Angela La Bella、Luisa M. Migneco、Rinaldo Marini Bettolo
DOI:10.1021/jo200945s
日期:2011.8.19
The problem of constructing diastereoselectively the C/D ring system of stemarane diterpenes from a bicyclo[2.2.2]octane intermediate was solved resulting in very simple synthesis of (+)-13-stemarene 1. The obtaining of the latter represents also a formal synthesis of (+)-18-deoxystemarin 2. In the key step, the epimeric mixture 10, dissolved in toluene, was converted by the action of TsOH into (+)-stemar-13-en-15-one 28.