1-Substituted b-Carbolines by a Pictet-Spengler Cyclization with Thioorthoesters and Carbon-Carbon Bond Formation via N-Sulfonyl Iminium Ions Generated From N,S-Sulfonyl Acetals

CLAUDIO C. SILVEIRA; LUCIANA FÉLIX; ANTONIO L. BRAGA; TEODORO S. KAUFMAN

ORGANIC LETTERS

ACS

Lugar: Washington; Año: 2005 vol. 7 p. 3701 - 3704

1523-7060

         The reaction of N-tosyltryptamines with thioortho esters, leading to 1-thiosubstituted tetrahydro-beta-carbolines under modified Pictet-Spengler conditions, is described. The 1-heterosubstituted beta-carbolines furnished 1-substituted â-carbolines upon reaction with Grignard reagents and silyl derivatives under Lewis acid promotion. beta-carbolines under modified Pictet-Spengler conditions, is described. The 1-heterosubstituted â-carbolines furnished 1-substituted â-carbolines upon reaction with Grignard reagents and silyl derivatives under Lewis acid promotion.