Formal synthesis of Abyssomicin C

An alternative strategy towards Abyssomicin C(1) is described. The key ene-diene intermediate is synthesized via a Kishi type coupling of an E/Z mixture of triene-iodide 7 and a suitably functionalized derivative of 2,4-dimethylglutaric acid. A final in situ isomerization/intramolecular Diels-Alder cyclization resulted in the formation of the known intermediate 3 as a single isomer in high yield. Further heating of 3 using excess of iodine, afforded iodo-derivative 23, having the entire carbon skeleton of Abyssomicin D. (c) 2006 Elsevier Ltd. All rights reserved.