- an alkaloid, C21H26N2O3, extracted from the bark of Corynanthe johimbe or Rauwolfia serpentina, used as a selective alpha-adrenergic receptor antagonist: purported to have aphrodisiac properties.
- an alkaloid found in the bark of the tree Corynanthe yohimbe. It is used in medicine as an adrenergic blocking agent. Formula: C 21 H 26 N 2 O 3
