Rhynchophylline
![Chemical structure of rhynchophylline](/Images/godic/202502/07/Rhynchophylline1158.png")
Rhynchophylline is an alkaloid found in certain Uncaria species (Rubiaceae), notably Uncaria rhynchophylla and Uncaria tomentosa. It also occurs in the leaves of Mitragyna speciosa (kratom), a tree native to Thailand. Chemically, it is related to the alkaloid mitragynine.