Synthesis of the tetrahydroisoquinoline alkaloid (+/-)-renieramycin G and A (+/-)-lemonomycinone analogue from a common intermediate.

The total synthesis of tetrahydroisoquinoline alkaloids (+/-)-renieramycin G (4) and a lemonomycinone analogue (7) is described. A general strategy to synthesize both the mono- and bistetrahydroisoquinoline alkaloids from a common advanced intermediate, 17, is presented.

New strategy for the synthesis of tetrahydroisoquinoline alkaloids.

[reaction: see text] A general strategy for the formation of 1,3-cis-substituted tetrahydroisoquinolines is described from ortho-iodo imines involving Larock isoquinoline synthesis, addition of organolithium compounds to unactivated isoquinolines, and ionic hydrogenation. In addition, a new synthesis of lactams via an unprecedented azide cyclization in the presence of a sulfonium ion is described.