title: Total synthesis and absolute stereochemical assignment of (+)- and (-)-galbulimima alkaloid 13.
abstract: We describe the total synthesis of (+)- and (-)-galbulimima alkaloid 13. The absolute stereochemistry of natural (-)-galbulimima alkaloid 13 is revised to 2S. Sequential use of catalytic cross-coupling and cross-metathesis reactions followed by an intramolecular Diels-Alder reaction provided the required trans-decalin AB-ring system and masked the C16 carbonyl as an N-vinyl carbamate for late-stage unveiling in the form of the necessary C16 enone. A vinyl radical cyclization secured the C-ring, while successful execution of our strategy for introduction of the CDE-ring system in complex galbulimima alkaloids provided the target pentacycle with complete diastereoselection.
authors.affiliation: Department of Chemistry, Massachusetts Institute of Technology, Cambridge, Massachusetts 02139, USA. movassag@mit.edu
authors.forename: Mohammad
authors.initials: M
authors.lastname: Movassaghi
authors.forename: Diana K
authors.initials: DK
authors.lastname: Hunt
authors.forename: Meiliana
authors.initials: M
authors.lastname: Tjandra
mesh_terms: D006571:Heterocyclic Compounds / Q000138:chemical synthesis* / Q000737:chemistry* / Q000145:classification; D015394:Molecular Structure; D013237:Stereoisomerism
chemical_list: C518378:Galbulimima alkaloid 13; D006571:Heterocyclic Compounds