<unk>  is an angiotensin-converting enzyme inhibitor used as an antihypertensive drug.  It is an alkaloid obtained from Rauwolfia serpentina and other species of Rauwolfia.
Rescinnamine
Theobromine
Nomifensine
Benzoctamine
Cimetropium bromide
Dihydroergocryptine
Guacetisal
Alfaxalone