Tryptolines

Tryptoline, also known as tetrahydro-β-carboline and tetrahydronorharmane, is a natural organic derivative of β-carboline. It is an alkaloid chemically related to tryptamines. Derivatives of tryptoline have a variety of pharmacological properties and are known collectively as tryptolines.

Pinoline is a β-carboline and methoxylated tryptoline (5-methoxytryptoline) long claimed to be produced in the pineal gland during the metabolism of melatonin, however its pineal occurrence remains controversial. Its IUPAC name is 6-methoxy-1,2,3,4-tetrahydro-β-carboline, usually abbreviated as 6-MeO-THBC, and its more common name is a contraction of "pineal β-carboline". The biological activity of this molecule is of interest as a potential free radical scavenger, also known as an antioxidant, and as a monoamine oxidase A inhibitor.

Tetrahydroharmine (THH), also known as 7-methoxy-1,2,3,4-tetrahydroharman (7-MeO-THH), is a fluorescent indole alkaloid and β-carboline that occurs in the tropical liana species Banisteriopsis caapi.

Tetrahydroharman, or tetrahydroharmane, also known as 1-methyl-1,2,3,4-tetrahydro-β-carboline, is a β-carboline and general name for one of two isomers:

6-MeO-THH, also known as 6-methoxy-1,2,3,4-tetrahydroharman, is a β-carboline (or more specifically a pinoline) derivative and a structural isomer of tetrahydroharmine (7-MeO-THH). It is mentioned in Alexander Shulgin's book TiHKAL (Tryptamines I Have Known and Loved), stating that 6-MeO-THH is very similar to the other carbolines. The compound has been isolated from certain plants of the Virola family.

Tetrahydroharmol is a bioactive β-carboline and harmala alkaloid. It acts as a reversible inhibitor of monoamine oxidase A.