Enantioselective strategy to the spirocyclic core of Palau'amine and related bisguanidine marine alkaloids.

Department of Chemistry, Texas A&M University, P.O. Box 30012, College Station, Texas 77843-3012, USA.

[structure: see text] An enantioselective strategy to the spirocyclic core found in the oroidin-derived family of bisguanidine marine alkaloids has been devised, premised on a biosynthetic proposal. Herein, we describe the successful implementation of this strategy, which entails a Diels-Alder reaction and a chlorination/ring contraction sequence that delivers the fully functionalized spirocyclic core. In this initial report, an intermolecular chlorination delivers a cyclopentane that is epimeric at C17 relative to the palau'amines and epimeric at C11 relative to the axinellamines.

PMID: 11388860 [PubMed - indexed for MEDLINE]