Pinoline

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.^[1] 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".^[2] The biological activity of this molecule is of interest as a potential free radical scavenger, also known as an antioxidant,^[3] and as a monoamine oxidase A inhibitor.^[4]

Pinoline

Names
Preferred IUPAC name 6-Methoxy-2,3,4,9-tetrahydro-1H-pyrido[3,4-b]indole
Other names 6-MeO-THBC; 5-MeO-TLN; Pinoline; 6-Methoxy-2,3,4,9-tetrahydro-1H-β-carboline; 6-Methoxy-1,2,3,4-tetrahydro-β-carboline; 6-Methoxy-tetrahydronorharman; 6-Methoxy-2,3,4,9-tetrahydro-1H-β-carboline
Identifiers
CAS Number	20315-68-8 N
3D model (JSmol)	Interactive image
ChemSpider	1797 N
ECHA InfoCard	100.161.873
PubChem CID	1868
UNII	BR3W85U4GS Y
CompTox Dashboard (EPA)	DTXSID30174203
InChI InChI=1S/C12H14N2O/c1-15-8-2-3-11-10(6-8)9-4-5-13-7-12(9)14-11/h2-3,6,13-14H,4-5,7H2,1H3 N Key: QYMDEOQLJUUNOF-UHFFFAOYSA-N N InChI=1/C12H14N2O/c1-15-8-2-3-11-10(6-8)9-4-5-13-7-12(9)14-11/h2-3,6,13-14H,4-5,7H2,1H3 Key: QYMDEOQLJUUNOF-UHFFFAOYAW
SMILES COC1=CC2=C(C=C1)NC3=C2CCNC3
Properties
Chemical formula	C12H14N2O
Molar mass	202.257 g·mol−1
Melting point	216 to 224 °C (421 to 435 °F; 489 to 497 K)
Except where otherwise noted, data are given for materials in their standard state (at 25 °C [77 °F], 100 kPa). N verify (what is YN ?) Infobox references

Bausch & Lomb filed a patent for a drug delivery device utilizing this molecule, designed to treat various ophthalmic disorders in 2006.^[5]

Pharmacology

One of pinoline's pharmacological properties is its ability to promote neurogenesis in vitro; even at trace concentrations.^[6]

Aluminium toxicity causes an increase in lipid peroxidation, with most damage occurring in the brain. A recent review of studies shows pinoline and melatonin to be effective at reducing the lipid peroxidation. Studies included both human and animal subjects. The studies’ results support that pinoline has antioxidant properties.^{[citation needed]}

Lipopolysaccharide is produced by Gram-negative bacteria and stimulates the production of free radicals which in turn cause lipid peroxidation. A recent study compared the effectiveness of melatonin and other similar compounds on the lipopolysaccharide induced lipid peroxidation. The results showed support for pinoline’s ability to reduce damage from lipid peroxidation^{[citation needed]}. Pinoline was also shown to be more effective than vitamin E at reducing lipopolysaccharide activity in the retina.^[7]

Another recent study compared the antioxidant properties of compounds from the tryptophan metabolic pathway in the pineal gland against oxidative damage to the lipids and proteins of synaptosomes. Synaptosomes isolated from rat brains were used in an experiment assessing damage by measuring malondialdehyde, 4-hydroxyalkenal, and carbonyl content in the proteins. Pinoline was shown to be the most powerful antioxidant. These results support the evidence for pinoline’s antioxidant abilities and the potential to protect against oxidative damage.^[8]

See also

• Substituted β-carboline
• 6-Methoxyharmalan
• Norharmane
• Harmane
• Harmala alkaloid