Tropane alkaloids atropine

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)... 

Belladonna contains tropane alkaloids, atropine, hyoscamine, and scopolamine, all... 

Tomatine Veratramine Veratridine Tropane alkaloids Atropine... 

The chief representatives of this group are the tropane alkaloids, atropine, its fero-isomer, Z-hyoscyamine, and Z-scopolamine (Z-hyoscine). They are all powerful mydriatic and cycloplegic drugs. Atropine is the most important in ophthalmology, and it is usually used as its neutral sulfate in 1% solution. When such a solution is instilled into the human eye, mydriasis begins in about half an hour and is complete in about an hour ... 

Although atropine is a known antidote against several toxic substances, its overdose can cause severe poisoning. As with other tropane alkaloids, atropine competitively blocks muscarinic acetylcholine receptor sites. This results in dilation of the pupil of the eye (mydriatic effect), dryness of the mucous membranes, especially of the mouth, and inhibition of activity of sweat glands (parasympatholytic action). At toxic doses, it causes palpitation, speech disturbance. 

Wasps produce bioactive polymethyleneamine alkaloids. Bugs (e.g., winter cherry bug) can consume tropane alkaloids (atropine and scopolamine) and convert scopolamine into atropine. Grasshoppers can produce azafluorenone alkaloids and can consume pyrrolizidine alkaloid by evolutionary development of their enzymatic system. Also, crickets, cad-disflies, dragonflies, and damselflies can use alkaloid feed. Their digestion alkaloids is not known in detail. 

The cholinergic hallucinogens all have common chemical constituents that are responsible for their pharmacological effects (Robbers et al. 1996). These are the tropane alkaloids hyoscyamine, scopolamine (or hyoscine), and atropine (figure 9.16). It is scopolamine, and not atropine or hyoscyamine, which primarily produces the central and hallucinogenic effects because it is the only one that passes the blood-brain barrier sufficiently. However, all three have peripheral effects. Datura stramonium contains 0.1-0.65% tropane alkaloids, which is principally... 

Figure 2.14 Two common tropane alkaloids in Solanum spp. (a) atropine Datura), and (b) cocaine (Erythroxylon coca).

The tropane alkaloids (—)-hyoscyamine and (—)-hyoscine are found in the toxic plants deadly nightshade (Atropa belladonna) and thornapple (Datura stramonium) and are widely used in medicine. Hyoscyamine, usually in the form of its racemate atropine, is used to dilate the pupil of the eye, and hyoscine is employed to control motion sickness. Both alkaloids are esters of (—)-tropic acid. 

The Mannich reaction was used for the first synthesis of tropine, the parent alcohol of the tropane alkaloids. One of the natural tropane alkaloids used medicinally is hyoscyamine, sometimes in its racemic form atropine. Hyoscyamine is an anticholinergic, competing with acetylcholine for the muscarinic site of the parasympathetic nervous system, and thus prevendng the passage of nerve impulses. 

Certain plants of the family Solanaceae, such as Atropa belladonna L., Hyoscyamus niger L., and Datura stramonium L., have been used medicinally for centuries in Europe because they contain tropane-type alkaloids.For example, atropine (1) [a racemic mixture of (+)- and (—)-hyoscyamine (2)] and (-)-hyoscyamine are competitive antagonists at the muscarinic acetylcholine receptor site, leading to antispasmodic and antiallergic effects. Scopolamine [(—)-hyoscine)] (3) is used in a transdermal patch for the prevention of motion sickness. Since these tropane alkaloids penetrate the blood-brain barrier, they also have psychoactive effects. ... 

Atropine (1) Ipratropium bromide (25) Tropane alkaloid Asthma... 

Atropine (1) Tiotropium bromide (26) Tropane alkaloid Chronic obstructive pulmonary disease... 

Tropane alkaloids Tropane Atropine Cocaine Hyoscyamine Scopolamine/ hyoscine... 

Tropane alkaloids have a tropane (C4N skeleton -f) nucleus. Structurally, these alkaloids synthesize as postcursors of pyrrolines (Figure 57). a, /3,

tropane alkaloids (e.g., atropine, hyoscyamine, cocaine, tropinone, tropine, littorine and cuscohy-grine) have a strong biological activity, especially as neurotransmitters. 

Plants containing indoleamines include Psilocybe mushrooms, morning glory and Virola. Plants containing tropane alkaloids such as the muscarinic antagonists scopolamine and atropine are found in some members of the Solanaceae plant family—including datura, mandrake, henbane and... 

These are the group of alkaloids that possess a 8-methyl-8-aza-hicyclo [l,2,3]octane or tropane skeleton, e.g. atropine, cocaine and scopolamine. Tropane alkaloids occur mainly in plants from the families Solanaceae and Erythroxylaceae. 8-Aza-hicyclo[l,2,3]octane, i.e. tropane without the 8-methyl group, is known as nortropane. 

Tropane is formed when pyrrolidine and piperidine are condensed. Closely related to tropane are tropine, the principal nucleus of the solanaceous alkaloids, atropine, hyoscyamine, hyoscine, and belladonnine, and ecgonine, the nucleus of cocaine (Figure 11.7). 

A new method for the rapid separation of alkaloids, inter alia atropine, has been elaborated, using chromatography on paper that is impregnated with zirconium oxide.57 Cation-exchange h.p.l.c. analysis of tropane alkaloids has been developed,58 followed by post-column derivatization using the fluorimetric ion-pair technique.58,59 Gas chromatography of tropanes has been reviewed.60... 

Proton61 and carbon-1362 n.m.r. spectroscopy have recently been used extensively for the analysis of tropane alkaloids. The non-equivalence of H-6 and H-7 on the one hand and of H-2 and H-4 on the other in atropine and scopolamine is due to the non-symmetrical shielding by the tropic acid moiety. The configuration of A-substituents, e.g. N-oxides, has been determined by studying the deshielding of the 6- and 7/3-hydrogens. All of these results should be useful for the identification of new tropane alkaloids and other related systems in the future. 

Fig. 7 Selected biotransformation products of diverse tropane alkaloids identified by LC-MS/MS approaches. Depicted metabolites are only an exert of those presented by Chen et al. for anisodamine (Ada) [6], atropine (Atr) [51], and scopolamine (Sep) [7] as well as by He et al. for benztropine (Benz) [59]. Structures were identified from in vivo and in vitro samples following diverse modes of MS/MS analysis as discussed in the section Biotransformation studies...

Incidental and accidental intake of atropine and scopolamine, which are the main tropane alkaloids in plants of the solanecae family, may provoke poisoning of man and livestock [11,13-15, 55, 57,119-122] causing agitation, aggression, hallucinations, dry mouth and skin, mydriasis, loss of consciousness followed by coma combined with tachycardia, hypotension, and hyperthermia [57, 121], A detailed statistical analysis of paediatric plant exposures in Germany within the years 1998-2004 has been provided by Pietsch et al. [123], They found that most prevalent victims of accidental plant exposures are children in the age of 1-6 years presumably being misled by the attractive plump berries. 

John H, Binder T, Hochstetter H, Thiermann H (2010) LC-ESI MS/MS quantification of atropine and six other antimuscarinic tropane alkaloids in plasma. Anal Bioanal Chem 396 751-763... 

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