Datura metel

Scopolamine (42), an optically active, viscous Hquid, also isolated from Solanaceae, eg. Datura metell. decomposes on standing and is thus usually both used and stored as its hydrobromide salt. The salt is employed as a sedative or, less commonly, as a prophylactic for motion sickness. It also has some history of use ia conjunction with narcotics as it appears to enhance their analgesic effects. BiogeneticaHy, scopolamine is clearly an oxidation product of atropiae, or, more precisely, because it is optically active, of (—)-hyoscyamiae. 

Datura Metel. Fruits, 0-12 leaves, 0-2 to 0-5 roots, 0-1 to 0-2 seeds, 0-2 to 0-5. Usually mainly hyoscine occasionally a little atropine or hyoscyamine. worHyoscyamine has also been found.No hyoscine (Libizov ). 

The alkaloid can usually be obtained from the mother liquors of hyoscyamine, but Datura Metel, in which hyoscine is the chief constituent, was the better primary source but may now prove less valuable than selected Duboisia spp. (p. 66). A process of manufacture has been described by Chemnitius, and a method for the recovery of 1-hyoscine from racemised base by Schukina et al. A method for its estimation in presence of opium alkaloids has been devised bj Wallen and Callback. 

It may be noted that Datura Metel, in which hyoscine is usually the predominant alkaloid, has been recorded in one instance by Libizov as containing hyoscyamine, but no hyoscine, and a similar difference is mentioned for Scopolia lurida. ... 

The earlier alkaloid literature contains numerous reports of studies aimed at discovering the existence of chemotypes involving these pharmacologically important compounds. An example of this sort of study comes from the work of Karnick and Saxena (1970) who were interested in the effect of elevation on total alkaloid content of Datura metel L. (Solanaceae), an important source of hyoscyamine [26]... 

Table 2.12 Alkaloid variation with elevation in Datura metel (from Karnick and Saxena, 1970)...

Almost as a joke, I suggested that they substitute the seed of the Himalayan Datura, Datura metel, for the LSD. Daturas are... 

A. Alkaloids 1. Belladonna-type solanaceous tropane alkaloids [Atropine (1), (—)-Hyoscyamine (2), Scopolamine ((—)-Hysoscine)(3)] Atropa belladonna L. (belladonna), Datura metel L., D. stramonium L. (jimson weed), Hyoscyamus niger L. (henbane), Mandragora officinarum L. (European mandrake), and other solanaceous species Anticholinergics (parasympatholytics)... 

Datura metel is probably the most readily available source of hyoscine. The powdered drug is extracted with hot alcohol and the crude alkaloids are isolated in the same way as has been described under hyoscyamine, except that sodium bicarbonate is employed, instead of ammonia, for liberating the bases. The alkaloid is neutralised exactly with hydrobromic acid and the solution of the hydrobromide concentrated. The salt which crystallises out on cooling is separated and purified by recrystallisation from water, until of constant melting point. 

Datura metel Rhododendrum Innocuous herbs Chinese herbals Tomlinson et al., 2000... 

P. notoginseng, P. zingerberensis Panax quinquefolius Eleuthrococcus senticosus Amorhophallus konjac Hydrastis canadensis Coptis chinensis Citrus paradisi Cyamopsis tetra-gonoloba Paullinia cupana Commiphora mukul Crategus monobyna Podophyllum emodi Datura metel Aesculus hippocastanum Ormosia coccinea Callilepsis laureola Juniperus spp. 

In agreement with similar experiments on nicotine and hyoscyamine Datura metel) iV-methylputrescine (24) was a much better precursor for cuscohygrine and hyoscyamine in S. lurida than either putrescine or ornithine. [2- " C,(5- N]Omithine was incorporated into cuscohygrine with no loss of relative to and thus the nitrogen atom in cuscohygrine arises specifically from the 5-amino-group of ornithine. It was concluded from these data that decarboxylation and iV-methylation precede cyclisation to the N-methyl-pyrrolidine ring, with 5-Af-methylaminobutyraldehyde (25) or its cyclic form (26) as an intermediate a similar role for the latter compound has been demonstrated in nicotine biosynthesis. ... 

N. tfibacuTn of nomicotine in N. glutinosa and of anabasine in N. glauca. In the tropane group, i-hyoscyamine predominates in A. belladonna and f-hyoscine in Datura metel L. (68). The distribution of the alkaloids in a graft whose stock and scion produce different kinds may thus prove illuminating. 

Datura Metel, in which Z-scopolamine is the chief alkaloid constituent, is used in the technical manufacture of this alkaloid (240). The finely powdered meal is moistened with 10% aqueous potassium hydroxide solution and is extracted with ether. The purified extract is converted to the hydrobromide and crystallized from a mixture of ethanol and acetone. The pure hydrobromide, upon conversion to the free base, gives a crystalline mmiohydrate from ether the anhydrous base is a sirup. 

Scopolamine is found in the leaves of Datura metel L., D. meteloides L., and D. fastuosa var. alba (Cordell 1978). It is used as a sedative, a preanesthetic agent, and in the treatment of motion sickness (Merck 1989). 

Datura metel Suspension Tropine plus tropic acid Acetyltropine 379... 

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