Indoles, VI: Lactamisation of 4,9-Dihydropyranoindol-1(3H)-ones with Methylamine.- A New Synthetic Route to Strychnocarpine and its Derivatives

Article abstract of DOI:10.1002/ardp.19883210708

The lactamisation of the pyranoindolones 3a-g - available from 1 or 2 -represents a simple synthesis of strychnocarpine (4a) and its substituted derivatives 4b-g, 5b,c.Reduction gives the tetrahydro-β-carbolines 6a-d,f,h.