tetrahydro-Harmine

2,3,4,9-tetrahydro-7-methoxy-1-methyl-1H-pyrido[3,4-b]indole
\n tetrahydro-Harmine (THH) is a fluorescent indole alkaloid extracted from B. caapi, a woody vine that is used to produce a psychoactive beverage, ayahuasca, which has been ritually ingested for medicoreligious purposes throughout South America since pre-Columbian times.{24007} THH inhibits monoamine oxidase (MAO)-A and MAO-B with much weaker potency (IC50s = 74 nM and >100 μM, respectively) compared to the companion harmala alkaloids also found in B. caapi: harmaline (Item No. 10995; IC50s = 2.5 nM and 25 μM, respectively) and harmine (Item No. 10010324; IC50s = 2 nM and 20 μM, respectively).{24009,24008}