Other Names

Tropanalkaloide, tropanes, tropeine

Tropane alkaloids are esters of tropanal combined

with various acids. They occur primarily in

nightshades (Solanaceae), especially the psychoactive

ones. The most important psychoactive

tropane alkaloids are atropine, scopolamine, and

hyoscyamine. These substances are "quickly

absorbed through the mucous membranes but

also through the intact skin" (Roth et al. 1994,

944*). For this reason, plant preparations in the

form of ointments with these tropane alkaloids

can induce psychoactive effects (cf. Datura

innoxia, witches' ointments). Atropine, scopolamine,

and hyoscyamine are found in the genera

Atropa, Brugmansia, Datum, Hyoscyamus, Iochroma,

]uanulloa, Mandragora, Solandra, and Scopolia.

The psychoactive tropane alkaloid hyoscyamine

(cf. Hyoscyamus niger) occurs in the following

nightshades in concentrations that appear to make

them useful for psychoactive purposes (Festi 1995,

132 f.*): Anthoceris littorea Labill. (herbage),

Crenedium spinescens Haegi (leaves), Cyphanthera

anthocercidea (Ev. Muel!.) Haegi (leaves),

Mandragora caulescens C.B. Clarke (entire plant;

cf. Mandragora spp.), Physochlaina praealta

(Decne.) Miers (entire plant), and Scopolia lurida

Dunal (roots; cf. Scopolia carniolica). As a plant

dries, the hyoscyamine it contains is usually

transformed into its analog scopolamine. The

profile of effects of hyoscyamine is essentially the

same as that of scopolamine.

Tropanes and cocaine are chemically related

and can under certain conditions elicit similar

pharmacological effects (Sauerwein et al. 1993).

The tropane alkaloid 2-tropanone is a metabolic

product of cocaine. Tropane alkaloids occur in

most if not all Erythroxylum species (AI-Said et al.

1989). The bark of Erythroxylum zambesiacum N.

Robson has been found to contain various

tropanes (Christen et al. 1993). The root bark of

Erythroxylum hypericifolium Lam., a species indigenous

to Mauritius that is used in folk medicine

to treat kidney problems, contains large amounts

of hygrine as well as other tropanes (e.g., cuscohygrine)

(AI-Said et al. 1989). Both hygrine and

cuscohygrine are also found in the leaves and bark

of the two coca species Erythroxylum coca and

Erythroxylum novogranatense (AI-Said et al. 1989,

672). The leaves of the Southeast Asian species

Erythroxylum cuneatum (Wall.) Kurz, which is

used in Malaysia as a tonic, were found to contain as their primary alkaloid (±)-3<X,613-dibenzoyloxytropane;

another major constituent in the leaves is

nicotine. The main alkaloid in the leaves of

another ethnomedicinally useful Southeast Asian

species, Erythroxylum ecarinatum Burck., is tropacacaine.

The root bark of the Australian species

Erythroxylum australe Ev. Muell. also contain

numerous tropanes (meteloidine) (EI-Imam et al.

1988).

Tropane alkaloids also appear to be present in

the Proteaceae Family, e.g., in the species Knightia

strobolina (EI-Imam et aL 1988:2182). In Australia,

several members of the genera Hakea and Banksia

are used to produce wine.

The recent discovery of tropane alkaloids

(tropine, tropinone, cuscohygrine, hygrine) in

field bindweed (Convolvulus arvensis 1.; cf. Convolvulus

tricolor) is very interesting; the species

also contains ergot alkaloids (Todd et al. 1995).

Tropane alkaloids have also been found in the

hedge bindweed Calystegia sepium (1.) R. Br. [syn.

Convolvulus sepium] (Goldmann et al. 1990).
Literature

See also the entries for atropine and scopolamine.

Bauer, Eduard. 1919. Studium aber die Bedeutung der

Alkaloide in pharmakognostisch wichtigen

Solanaceen, besonders in Atropa Belladonna und

Datura Stramonium. Bern: Hallwag.

Christen, P., M. F. Roberts, J. D. Phillipson, and W. C.

Evans. 1993. Recent aspects of tropane alkaloid

biosynthesis in Erythroxylum zambesiacum stem

bark. Planta Medica 59 supp!.: A583-84.

Goldmann, Arlette, Marie-Louise Milat, Paul-Henri

Ducrot, Jean-Yves Lallemand, Monique Maille,

Andree Lepingle, Isabelle Charpin, and David

Tepfer. 1990. Tropane derivates from Calistegia

sepium. Phytochemistry 29 (7): 2125-27.

Imam, Yahia M. A. e1-, William C. Evans, and

Raymond J. Grout. 1988. Alkaloids of

Erythroxylum cuneatum, E. ecarinatum and E.

australe. Phytochemistry 27 (7): 2181-84.

Said, Mansour S. al-, William C. Evans, and

Raymond J. Grout. 1989. Alkaloids of

Erythroxylum hypericifolium stem bark.

Phytochemistry 28 (2): 671-73.

Sauerwein, M., F. Sporer, and M. Wink. 1993.

Allelochemical properties of derivatives from

tropane and ecgonine. Planta Medica 59 suppL:

A662

Todd, G. Fred, F. R. Stermitz, P. Schultheiss, A. P.

Traub-Dargatz, and J. Traub-Dargatz. 1995.

Tropane alkaloids and toxicity of Convolvulus

arvensis. Phytochemistry 39:301-3.

Xiao, P., and 1. Y. He. 1983. Ethnopharmacologic

investigation on tropane-containing drugs in

Chinese Solanaceous plants. Journal of

Ethnopharmacology 8: 1-18.

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