Total Synthesis of (−)-Lepadiformine A via Radical Translocation–Cyclization Reaction
Masashi Shimomura, Manabu Sato, Hiroki Azuma, Juri Sakata, Hidetoshi Tokuyama
Abstract
Total synthesis of (-)-lepadiformine A featuring construction of the 1-azaspiro[4.5]decane skeleton by a highly diastereoselective radical translocation-cyclization reaction of a γ-lactam derivative bearing a chiral butenolide moiety is described. The enantioselective construction of butenolide is conducted via Krische's catalytic asymmetric allylation protocol. After the radical translocation-cyclization reaction, a hydroxymethyl group at the C-13 position was stereoselectively introduced by a one-pot partial reduction-allylation protocol of the unprotected lactam derivative. Finally, the total synthesis is completed by formation of a C ring.
Topics & Concepts
ChemistryRadical cyclizationChromosomal translocationTotal synthesisCombinatorial chemistryStereochemistryMedicinal chemistryBiochemistryGeneAdvanced Synthetic Organic ChemistryChemical synthesis and alkaloidsSynthetic Organic Chemistry Methods