N,N-dimethyltryptophan is a naturally occurring alkaloid found in the Jequirity bean and other plants. It is closely related to L-abrine (N-methyl-L-tryptophan, not to be confused with abrin). It can be synthesized via a reductive alkylation of tryptophan .
Research has shown that tryptophan (and other amino acids) can be readily decarboxylated into tryptamines.  
This compound is NOT for human consumption or in vivo research and is strictly for other research purposes only. Available as the free zwitterion of the L-isomer.
 – http://noland.chem.umn.edu/content/reductive-amination-tryptophan-dimethyltryptophan
 – https://erowid.org/archive/rhodium/chemistry/tryptophan.html
 – https://erowid.org/archive/rhodium/chemistry/tryptamine.takano.html