Abstract
The cyclization of 1-(substituted-allyl)-1, 2, 5, 6-tetrahydro-2-benzylpyridines with Lewis acid was found to give novel benzomorphans consisted of a new four-ring system. The synthesized compounds have been found to possess a potent analgesic activity with low toxicity in mice in general, and some of them are several times as potent as pentazocine. The relationships between the analgesic activity and the molecular conformation of these compounds were also suggested in this paper.
