A novel approach to the diazatricyclic madangamine ABC ring system and the synthesis of an advanced, differentially protected intermediate for the synthesis of madangamine D is reported. Central to the success of this approach is the iodine(III)-mediated intramolecular oxamidation of an unsaturated O-methyl hydroxamate, a π-N-type cyclization which proceeds in high yield and with complete regioselectivity to generate the 2-azabicyclo[3.3.1]nonane (morphan) system encompassing rings A and C.
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Oxamidation of Unsaturated O-Alkyl Hydroxamates: Synthesis of the Madangamine Diazatricylic (ABC Rings) Skeleton.
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Department of Chemistry, University of Illinois at Chicago, 845 West Taylor Street, Room 4500, Chicago, Illinois 60607-7061, United States.
A novel approach to the diazatricyclic madangamine ABC ring system and the synthesis of an advanced, differentially protected intermediate for the synthesis of madangamine D is reported. Central to the success of this approach is the iodine(III)-mediated intramolecular oxamidation of an unsaturated O-methyl hydroxamate, a π-N-type cyclization which proceeds in high yield and with complete regioselectivity to generate the 2-azabicyclo[3.3.
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Department of Chemistry, University of Illinois at Chicago, 845 West Taylor Street, Chicago, Illinois 60607-7061, United States.
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University of Illinois at Chicago, Department of Chemistry, 845 West Taylor Street, Room 4500, Chicago, Illinois 60607-7061, USA.
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