title: Convergent approach to the tetracyclic core of the apparicine class of indole alkaloids via a key intermolecular nitrosoalkene conjugate addition.
abstract: Readily available methyl 3-formylindol-2-ylacetate and N-tosyl-4-chloro-3-piperidone oxime have been used to construct the tetracyclic skeleton of the apparicine class of monoterpene indole alkaloids in only four steps in 80% overall yield. Key transformations in this convergent approach involve use of an intermolecular ester enolate/nitrosoalkene conjugate addition to form the C-15/16 bond, followed by a reductive cyclization to construct the C-ring of the tetracycle.
authors.affiliation: Department of Chemistry, The Pennsylvania State University , University Park, Pennsylvania 16802, United States.
authors.forename: Pradeep S
authors.initials: PS
authors.lastname: Chauhan
authors.forename: Steven M
authors.initials: SM
authors.lastname: Weinreb
mesh_terms: D000470:Alkaloids / Q000138:chemical synthesis* / Q000737:chemistry; D003500:Cyclization; D026121:Indole Alkaloids / Q000138:chemical synthesis* / Q000737:chemistry; D015394:Molecular Structure; D009603:Nitroso Compounds / Q000737:chemistry*; D010091:Oximes / Q000737:chemistry*; D010881:Piperidones / Q000737:chemistry*; D013237:Stereoisomerism
chemical_list: D000470:Alkaloids; D026121:Indole Alkaloids; C000593340:N-tosyl-4-chloro-3-piperidone oxime; D009603:Nitroso Compounds; D010091:Oximes; D010881:Piperidones; C000593339:methyl 3-formylindol-2-ylacetate; C008811:pericalline