Nornicotine is an

alkaloid Alkaloids are a class of basic, naturally occurring organic compounds that contain at least one nitrogen atom. This group also includes some related compounds with neutral and even weakly acidic properties. Some synthetic compounds of simila ...

found in various plants including ''

Nicotiana ''Nicotiana'' () is a genus of herbaceous plants and shrubs in the family Solanaceae, that is indigenous to the Americas, Australia, Southwestern Africa and the South Pacific. Various ''Nicotiana'' species, commonly referred to as tobacco pla ...

'', the

tobacco Tobacco is the common name of several plants in the genus '' Nicotiana'' of the family Solanaceae, and the general term for any product prepared from the cured leaves of these plants. More than 70 species of tobacco are known, but the ...

plant. It is chemically similar to

nicotine Nicotine is a naturally produced alkaloid in the nightshade family of plants (most predominantly in tobacco and '' Duboisia hopwoodii'') and is widely used recreationally as a stimulant and anxiolytic. As a pharmaceutical drug, it is use ...

, but does not contain a

methyl group In organic chemistry, a methyl group is an alkyl derived from methane, containing one carbon atom bonded to three hydrogen atoms, having chemical formula . In formulas, the group is often abbreviated as Me. This hydrocarbon group occurs in ma ...

. It is a precursor to the carcinogen ''N''-nitrosonornicotine that is produced during the curing and processing of tobacco. Nornicotine can react in human saliva to form

N-nitrosonornicotine ''N''-Nitrosonornicotine (NNN) is a tobacco-specific nitrosamine produced during the curing and processing of tobacco. Toxicity It has been classified as a Group 1 carcinogen. Although no adequate studies of the relationship between exposure t ...

, a known type 1 carcinogen.

Synthesis

There are several routes for the synthesis of nornicotine. One route is the demethylation of nicotine, which can be accomplished by reaction with

silver oxide Silver oxide is the chemical compound with the formula Ag2O. It is a fine black or dark brown powder that is used to prepare other silver compounds. Preparation Silver oxide can be prepared by combining aqueous solutions of silver nitrate and a ...

\mathrm

Another route is the partial reduction of 3-

myosmine Myosmine is an alkaloid found in tobacco and other plants. Chemically, it is closely related to nicotine. It inhibits aromatase seven fold more potently than nicotine. It also releases dopamine in adult but not adolescent rats. See also * Cath ...

, which can be accomplished by standard

catalytic hydrogenation Hydrogenation is a chemical reaction between molecular hydrogen (H2) and another compound or element, usually in the presence of a catalyst such as nickel, palladium or platinum. The process is commonly employed to reduce or saturate organic ...

conditions using palladium as a catalyst or with sodium borohydride.. This reaction gives the

racemic In chemistry, a racemic mixture, or racemate (), is one that has equal amounts of left- and right-handed enantiomers of a chiral molecule or salt. Racemic mixtures are rare in nature, but many compounds are produced industrially as racemates. ...

product.

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Pharmacology

Nornicotine possess high affinity for alpha-6 and alpha-7 subunits of nAChRs. It also inhibits DAT in striatum via nAChR and releases dopamine in rats.

References

{{reflist Pyridine alkaloids Pyrrolidines Alkaloids found in Nicotiana 3-Pyridyl compounds