Synthesis of Tetrahydro-β-carbolines and Tetrahydroisoquinolines Fused to Pyrrolidines and Solution-Phase Parallel Acylation

Abstract

A structurally diverse library of potentially pharmacologically important compounds employing classical synthesis methods is described. These compounds are synthesized from beta-aryl pyrrolidines, providing products with the 2-arylethyl amine moiety, a structural feature often encountered in compounds active in the central nervous system. Tri- and tetracyclic scaffolds were obtained using the Pictet-Spengler reaction, resulting in hexahydropyrrolo[3,4-c]isoquinolines 1-3, an octahydropyrrolo[3',4':5,6]pyrido[3,4-b]indole 4, and a hexahydrofuro[2,3-d]pyrrolo[3,4-b]pyridine 5. These scaffolds were further derivatized in parallel fashion to make a 32-membered amide library with yields from 62 to 100% (90% average) and purities from 63 to 100% (93% average).