Diastereoselective nitrenium ion-mediated cyclofunctionalization: total synthesis of (+)-castanospermine.
The asymmetric total synthesis of the α-glucosidase inhibitor (+)-castanospermine is reported. The central theme in our approach to this polyhydroxylated alkaloid is the simultaneous generation of the piperidine ring and the C-1/8a erythro stereodiad through the diastereoselective, oxamidation of an unsaturated O-alkyl hydroxamate. This process is believed to proceed sequentially via singlet acylnitrenium and aziridinium ion intermediates.
Department of Chemistry, University of Illinois at Chicago, 845 West Taylor Street, Chicago, Illinois 60607-7061, United States.
Edward G
EG
Bowen
Duncan J
DJ
Wardrop
D000470:Alkaloids / Q000138:chemical synthesis* / Q000737:chemistry / Q000494:pharmacology; D002384:Catalysis; D003500:Cyclization; D065089:Glycoside Hydrolase Inhibitors; D007212:Indolizines / Q000138:chemical synthesis* / Q000737:chemistry / Q000494:pharmacology; D007477:Ions; D015394:Molecular Structure; D013237:Stereoisomerism; D054836:Indolizidines
D000470:Alkaloids; D065089:Glycoside Hydrolase Inhibitors; D007212:Indolizines; D007477:Ions; C037806:castanospermine; D054836:Indolizidines