Tropane alkaloids are a class of bicyclic .2.1

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 similar ...

s and

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

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 determination includes a chemist's specifying the molecular geometry and, when feasible and necessary, the electronic structure of the target molecule or other solid. Molecular geometry refers to the spatial arrangement of ...

. Tropane alkaloids occur naturally in many members of the plant family Solanaceae. Certain tropane alkaloids such as

cocaine Cocaine (from , from , ultimately from Quechua: ''kúka'') is a central nervous system (CNS) stimulant mainly used recreationally for its euphoric effects. It is primarily obtained from the leaves of two Coca species native to South Ameri ...

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 Anticholinergics (anticholinergic agents) are substances that block the action of the neurotransmitter called acetylcholine (ACh) at synapses in the central and peripheral nervous system. These agents inhibit the parasympathetic nervous sy ...

or stimulants.

Classification

Anticholinergics

Anticholinergic drug Anticholinergics (anticholinergic agents) are substances that block the action of the neurotransmitter called acetylcholine (ACh) at synapses in the central and peripheral nervous system. These agents inhibit the parasympathetic nervous system ...

s and

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

s: * Atropine,

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. ...

hyoscyamine, from the deadly nightshade ('' Atropa belladonna'') * Hyoscyamine, the ''levo''- isomer of atropine, from henbane (''

Hyoscyamus niger ''Hyoscyamus niger'', commonly known as henbane, black henbane, or stinking nightshade, is a poisonous plant in the nightshade family Solanaceae. It is native to temperate Europe and Siberia, and naturalised in Great Britain and Ireland. Histor ...

''), mandrake (''

Mandragora officinarum ''Mandragora officinarum'' is the type species of the plant genus '' Mandragora'' in the nightshade family Solanaceae. It is often known as mandrake, although this name is also used for other plants. , sources differed significantly in the specie ...

'') and the sorcerers' tree (''

Latua pubiflora ''Latua pubiflora'' (Griseb.) Baillon, (common name in Spanish: ''árbol de los brujos'', ''tree of the sorcerers'') is the single species of the monotypic genus ''Latua'' Phil., endemic to the coastal mountains of southern Chile. A shrub or sm ...

''). * Scopolamine, from henbane and '' Datura'' species (Jimson weed) All three acetylcholine-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 ...

'' (angel trumpets), a relative of '' Datura''. The same is also true of many other plants belonging to subfamily

Solanoideae Solanoideae is a subfamily of the flowering plant family Solanaceae, and is sister to the subfamily Nicotianoideae. Within Solanaceae, Solanoideae contains some of the most economically important genera and species, such as the tomato (''Solanum l ...

of the Solanaceae, 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.Eich, Prof. Dr. Eckhart, 2008, ''Solanaceae and Convolvulaceae: Secondary Metabolites - Biosynthesis, Chemotaxonomy, Biological and Economic Significance (A Handbook)'' pub. Springer-Verlag Berlin Heidelberg, .

Stimulants

Stimulants and cocaine-related alkaloids: *

Cocaine Cocaine (from , from , ultimately from Quechua: ''kúka'') is a central nervous system (CNS) stimulant mainly used recreationally for its euphoric effects. It is primarily obtained from the leaves of two Coca species native to South Ameri ...

, from coca plant (''

Erythroxylum coca ''Erythroxylum coca'' is one of two species of cultivated coca. Description The coca plant resembles a blackthorn bush, and grows to a height of . The branches are straight, and the leaves, which have a green tint, are thin, opaque, oval, and tap ...

'') *

Ecgonine Ecgonine (tropane derivative) is a tropane alkaloid found naturally in coca leaves. It has a close structural relation to cocaine: it is both a metabolite and a precursor, and as such, it is a controlled substance in many jurisdictions, as are s ...

, a precursor and metabolite of cocaine *

Benzoylecgonine Benzoylecgonine is the main metabolite of cocaine, formed by the liver and excreted in the urine. It is the compound tested for in most cocaine urine drug screens. Pharmacokinetics Chemically, benzoylecgonine is the benzoate ester of ecgonine. I ...

, a metabolite of cocaine *

Hydroxytropacocaine Hydroxytropacocaine is a tropane alkaloid found in ''Erythroxylum coca''. See also * Coca alkaloid Coca alkaloids are the alkaloids found in the coca plant, ''Erythroxylum coca''.Variation of Alkaloid Content in Erythroxylum coca Leaves from L ...

, from coca plant (''Erythroxylum coca'') *

Methylecgonine cinnamate Methylecgonine cinnamate is a natural tropane alkaloid found within the coca plant. Its more common name, cinnamoylcocaine, reflects its close structural similarity to cocaine. It is pharmacologically inactive,Merck Chemical Index, 1985 but some ...

, from coca plant (''Erythroxylum coca'')

Others

* Catuabines, found in

catuaba The name Catuaba ( , via Portuguese from Guarani) is used for the infusions of the bark of a number of trees native to Brazil. The most widely used barks are derived from the trees '' Trichilia catigua'' and '' Erythroxylum vaccinifolium''. Othe ...

, an infusion or dry extract made from '' Erythroxylum vaccinifolium'' * Scopine Synthetic analogs of tropane alkaloids also exist, such as the

phenyltropane Phenyltropanes (PTs) were originally developed to reduce cocaine addiction and dependency. In general these compounds act as inhibitors of the plasmalemmal monoamine reuptake transporters. Although RTI holds a strong position in this field, ...

s. 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

{{Reflist Deliriants