Lefetamine (Santenol) is a drug which is a stimulant and also an analgesic with effects comparable to codeine. Lefetamine-related 1,2-diphenylethylamines were invented in the 1940s and showed weak analgesic activity. It was investigated in Japan in 1950s. The l-isomere showed weak analgetic action comparable to codeine and antitussive action far w...