Dragmacidin E synthesis studies. Preparation of a model cycloheptannelated indole fragment
Ken S Feldman1, Paiboon Ngernmeesri
1Department of Chemistry, The Pennsylvania State University, University Park, Pennsylvania 16802, USA. ksf@chem.psu.edu
Abstract:
[reaction: see text] The conversion of N-2,2-dichloropropionyl indole methyl ester into a tetracyclic cycloheptannelated indole model compound for the synthesis of dragmacidin E was accomplished in 10 steps. Key reactions include a Witkop cyclization to fashion a C-C bond at C(4) of the indole nucleus and a subsequent Dieckmann cyclization to deliver the desired cycloheptanoid ring.
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