CHIRAL ACETYLENIC SULFOXIDE IN ENANTIOSELECTIVE SYNTHESIS OF TETRAHYDROISOQUINOLINE AND TETRAHYDRO-BETA-CARBOLINE ALKALOIDS - TOTAL SYNTHESIS OF (R)-(-CARNEGINE AND (R)-(+)-TETRAHYDROHARMAN())

Michael addition of 2-(3,4-dimethoxyphenyl)ethylamine 3 or tryptamine 4 onto chiral acetylenic sulfoxides 2 followed by acid induced cycliza tion afforded the basic alkaloid skeleton of tetraisoquinoline and tet rahydro-beta-carboline in high to moderate diastereoselectivity. Optic ally pure (R)-(+)-carnegine and (R)-(+)-tetrahydroharman have been syn thesized.