Concise Total Synthesis and Stereochemical Assignment of (–)-Psychotridine.

Abstract

We report the first enantioselective total synthesis and stereochemical assignment of (–)-psychotridine. Application of our diazene-directed assembly of enantiomerically enriched cyclotryptamines afforded a highly convergent synthesis of the pentameric alkaloid, allowing its detailed structural assignment. Highlights of the synthesis include introduction of four quaternary stereocenters with complete stereochemical control in a single step via photoextrusion of three molecules of dinitrogen from an advanced intermediate and metal-catalyzed C–H amination in complex settings.

Total Synthesis and Stereochemical Assignment of (−)-Psychotridine

“…Highlights of the synthesis include the introduction of four quaternary stereocenters with complete stereochemical control in a single step via the photoextrusion of three molecules of dinitrogen from the advanced trisdiazene intermediate (+)- 6 and the application of Ir- and Rh-catalyzed C–H amination chemistry in complex settings. The consistency of the characterization data for our synthetic sample of (−)-psychotridine ( 4 ) with all available literature data for (−)-psychotridine ( 4 ), in addition to the comparison with an expanded data set we acquired using a natural sample of psychotridine ( 4 ), confirmed their identical molecular structures, allowing our unambiguous stereochemical assignment of the pentameric alkaloid 4 …”