Total Synthesis of the Myrioneuron Alkaloid (–)-Schoberine B and Its Enantiomer (+)-Schoberine B

Abstract

A dynamic kinetic asymmetric transformation, involving the generation of four stereogenic centers with a well-defined configuration, occurs in the cyclocondensation of diastereomeric mixtures of 2-oxocyclohexanepropionic acid racemates <strong> </strong>with (1<em>S</em>,2<em>R</em>)-<em>cis</em>-aminoindanol: two major tetracyclic lactams, that differ in the configuration of the four stereocenters on the decahydroquinoline moiety were obtained. From the above lactams, the removal of the chiral auxiliary, the introduction of a 2-piperidone ring, and the closure of the diazine ring complete the first enantioselective total synthesis of the <em>Myrioneuron</em> alkaloid (–)-schoberine B and its enantiomer (+)-schoberine B.