ent-Halimic acid has been used in the synthesis of the quinone/hydroquinone sesquiterpenes (-)-aureol, (-)-smenoqualone, (-)-neomamanuthaquinone and in the formal synthesis of (-)-cyclosmenospongine. (C) 2010 Elsevier Ltd. All rights reserved.
Synthesis of (±)-Aureol by Bioinspired Rearrangements
A bioinspired and sustainable procedure for the straightforward synthesis of (+/-)-aureol has been achieved in eight steps (14% overall yield) from epoxyfarnesol. The key steps are the titanocene(III)-catalyzed radical cascade cyclization of an epoxyfarnesol derivative and a biosynthetically inspired sequence of 1,2-hydride and methyl shifts.