Tropane alkaloids are a class of bicyclic .2.1

alkaloid Alkaloids are a broad class of natural product, naturally occurring organic compounds that contain at least one nitrogen atom. Some synthetic compounds of similar structure may also be termed alkaloids. Alkaloids are produced by a large varie ...

s and

secondary metabolite Secondary metabolites, also called ''specialised metabolites'', ''secondary products'', or ''natural products'', are organic compounds produced by any lifeform, e.g. bacteria, archaea, fungi, animals, or plants, which are not directly involved ...

s that contain a

tropane Tropane is a nitrogenous bicyclic organic compound. It is mainly known for the other alkaloids derived from it, which include atropine and cocaine, among others. Tropane alkaloids occur in plants of the families Erythroxylaceae (including coca) ...

ring in their

chemical structure A chemical structure of a molecule is a spatial arrangement of its atoms and their chemical bonds. Its determination includes a chemist's specifying the molecular geometry and, when feasible and necessary, the electronic structure of the target m ...

. Tropane alkaloids occur naturally in many members of the plant family

Solanaceae Solanaceae (), commonly known as the nightshades, is a family of flowering plants in the order Solanales. It contains approximately 2,700 species, several of which are used as agricultural crops, medicinal plants, and ornamental plants. Many me ...

. Certain tropane alkaloids such as

cocaine Cocaine is a tropane alkaloid and central nervous system stimulant, derived primarily from the leaves of two South American coca plants, ''Erythroxylum coca'' and ''Erythroxylum novogranatense, E. novogranatense'', which are cultivated a ...

and scopolamine are notorious for their psychoactive effects, related usage and cultural associations. Particular tropane alkaloids such as these have pharmacological properties and can act as anticholinergics or

stimulants Stimulants (also known as central nervous system stimulants, or psychostimulants, or colloquially as uppers) are a class of drugs that increase alertness. They are used for various purposes, such as enhancing attention, motivation, cognitio ...

Classification

Anticholinergics

Anticholinergic drugs and

deliriant Deliriants are a subclass of hallucinogen. The term was coined in the early 1980s to distinguish these drugs from psychedelics such as LSD and dissociatives such as ketamine, due to their primary effect of causing delirium, as opposed to th ...

s: *

Atropine Atropine is a tropane alkaloid and anticholinergic medication used to treat certain types of nerve agent and pesticide poisonings as well as some types of slow heart rate, and to decrease saliva production during surgery. It is typically give ...

racemic In chemistry, a racemic mixture or racemate () is a mixture that has equal amounts (50:50) 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 r ...

hyoscyamine, from the deadly nightshade (''

Atropa belladonna ''Atropa bella-donna'', commonly known as deadly nightshade or belladonna, is a toxic perennial herbaceous plant in the nightshade family Solanaceae, which also includes tomatoes, potatoes and eggplant. It is native to Europe and Western Asia, i ...

'') *

Hyoscyamine Hyoscyamine (also known as daturine or duboisine) is a naturally occurring tropane alkaloid and plant toxin. It is a secondary metabolite found in certain plants of the family Solanaceae, including Hyoscyamus niger, henbane, Mandragora officina ...

, the ''levo''-

isomer In chemistry, isomers are molecules or polyatomic ions with identical molecular formula – that is, the same number of atoms of each element (chemistry), element – but distinct arrangements of atoms in space. ''Isomerism'' refers to the exi ...

of atropine, from henbane (''

Hyoscyamus niger Henbane (''Hyoscyamus niger'', also black henbane and stinking nightshade) is a poisonous plant belonging to tribe Hyoscyameae of the nightshade family ''Solanaceae''. Henbane is native to temperate Europe and Siberia, and naturalised in Great B ...

''), mandrake ('' Mandragora officinarum'') and the sorcerers' tree ('' Latua pubiflora''). * Scopolamine, from henbane and ''

Datura ''Datura'' is a genus of nine species of highly poisonous, Vespertine (biology), vespertine-flowering plants belonging to the nightshade family (Solanaceae). They are commonly known as thornapples or jimsonweeds, but are also known as devil's t ...

'' species (Jimson weed) All three

acetylcholine Acetylcholine (ACh) is an organic compound that functions in the brain and body of many types of animals (including humans) as a neurotransmitter. Its name is derived from its chemical structure: it is an ester of acetic acid and choline. Par ...

-inhibiting chemicals can also be found in the leaves, stems, and flowers in varying, unknown amounts in ''

Brugmansia ''Brugmansia'' is a genus of seven species of flowering plants in the nightshade family Solanaceae. They are woody trees or shrubs, with pendulous flowers, and have no spines on their fruit. Their large, fragrant flowers give them their common n ...

'' (angel trumpets), a relative of ''

''. The same is also true of many other plants belonging to subfamily Solanoideae of the

, the alkaloids being concentrated particularly in the leaves and seeds. However, the concentration of alkaloids can vary greatly, even from leaf to leaf and seed to seed.

Stimulants

Stimulant Stimulants (also known as central nervous system stimulants, or psychostimulants, or colloquially as uppers) are a class of drugs that increase alertness. They are used for various purposes, such as enhancing attention, motivation, cognition, ...

s and cocaine-related alkaloids: *

Cocaine Cocaine is a tropane alkaloid and central nervous system stimulant, derived primarily from the leaves of two South American coca plants, ''Erythroxylum coca'' and ''Erythroxylum novogranatense, E. novogranatense'', which are cultivated a ...

, from coca plant ('' Erythroxylum coca'') * Ecgonine, a precursor and metabolite of cocaine * Benzoylecgonine, a metabolite of cocaine * Hydroxytropacocaine, from coca plant (''Erythroxylum coca'') * Methylecgonine cinnamate, from coca plant (''Erythroxylum coca'')

Others

* Catuabines, found in catuaba, an infusion or dry extract made from '' Erythroxylum vaccinifolium'' * Scopine Synthetic analogs of tropane alkaloids also exist, such as the phenyltropanes. They are not considered to be alkaloids per definition.

Biosynthesis

The biosynthesis of the tropane alkaloids have attracted intense interest because of their high physiological activity as well as the presence of the bicyclic

core.

References

{{Chemical classes of psychoactive drugs Deliriants