title: The tandem ring opening/ring closing metathesis route to oxaspirocycles: an approach to phelligridin G.
abstract: Phelligridin G is an unusual natural product that contains an embedded  spiro-fused furanone core. We have investigated two furan-based synthetic approaches towards the spirocyclic core structure of this natural product from readily available  2-phenylfurans. Although initial studies involving an oxidative cyclization were unsuccessful, we were ultimately able to access this key system through a sequential intermolecular furan Diels-Alder reaction followed by a metathesis-based reorganization. A related approach led to an expanded C ring to form spiro-fused pyran spirocycles.
authors: Department of Pharmaceutical Sciences, University of Connecticut, Storrs, CT 06269, USA.
authors: Harold D
authors: HD
authors: Cooper
authors: Dennis L
authors: DL
authors: Wright
mesh_terms: D001578:Benzopyrans / Q000138:chemical synthesis* / Q000737:chemistry; D002625:Chemistry, Organic / Q000379:methods*; D003500:Cyclization; D061565:Cycloaddition Reaction; D055664:Electrochemical Techniques; D010084:Oxidation-Reduction; D011124:Polyporaceae / Q000737:chemistry; D013141:Spiro Compounds / Q000138:chemical synthesis* / Q000737:chemistry
chemical_list: D001578:Benzopyrans; D013141:Spiro Compounds; C507450:phelligridin G