The formation of optically active 1,3-disubstituted and 1,1,3-trisubstituted tetrahydro-β-carbolines using a modified Pictet–Spengler reaction

Abstract

Optically active 1,3-disubstituted and 1,1,3-trisubstituted 1,2,3,4-tetrahydro-β-carbolines were formed by the reaction of variours N^α, Nⁱⁿ-substituted (S)-tryptophan methyl esters with methyl propynoate or dimethyl butynedioate respectively; the stereoselectivity of the reactions is reported.