Total synthesis of (+/-)-stenine using the IMDAF cycloaddition of a 2-methylthio-5-amido-substituted furan.
[reaction: see text]. The intramolecular [4 + 2]-cycloaddition of a 2-methylthio-5-amidofuran was used to create the azepinoindole skeleton present in the Stemona alkaloid stenine. The rearranged cycloadduct was converted to stenine (1) in 11 additional steps via a sequence that features a Crabtree catalyst directed hydrogenation (9-->10), iodolactonization (2-->11), and a Keck allylation (11-->12).
Ginn
John D
JD
Department of Chemistry, Emory University, Atlanta, Georgia 30322, USA.
Padwa
Albert
A
D000470:Alkaloids / Q000138:chemical synthesis*; D002384:Catalysis; D003500:Cyclization; D005663:Furans / Q000138:chemical synthesis*; D007202:Indicators and Reagents; D009682:Magnetic Resonance Spectroscopy; D008968:Molecular Conformation; D013438:Sulfhydryl Compounds / Q000138:chemical synthesis*
D000470:Alkaloids; D005663:Furans; D007202:Indicators and Reagents; D013438:Sulfhydryl Compounds; C441784:stenine