Picrotoxin
Structural formula | |||||||||||||||||||
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Picrotin (top), picrotoxinin (bottom) | |||||||||||||||||||
General | |||||||||||||||||||
Surname | Picrotoxin | ||||||||||||||||||
other names |
Cocculin |
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Molecular formula | C 15 H 16 O 6 • C 15 H 18 O 7 | ||||||||||||||||||
Brief description |
white to yellowish powder |
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External identifiers / databases | |||||||||||||||||||
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properties | |||||||||||||||||||
Molar mass | 292 and 310 g · mol -1 | ||||||||||||||||||
Physical state |
firmly |
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Melting point |
203-204 ° C |
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solubility |
4.1 g l −1 |
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safety instructions | |||||||||||||||||||
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Toxicological data | |||||||||||||||||||
As far as possible and customary, SI units are used. Unless otherwise noted, the data given apply to standard conditions . |
Picrotoxin , also known as Cocculin , is the name for an equimolar mixture of two naturally occurring chemical compounds : Picrotoxinin, C 15 H 16 O 6 and Picrotin, C 15 H 18 O 7 , both sesquiterpene lactones from the myrtle myrtle . Picrotoxin was first isolated in 1812 by Boullay from the fruits ("Kokkelskörner") of the plant.
properties
The component picrotin differs from picrotoxinin only in that the double bond of the isopropenyl group is hydrated in the structure, i.e. instead of an isopropenyl there is a 2-hydroxyisopropyl radical. In contrast to the non-toxic picrotin, picrotoxinin is highly toxic; the lethal dose for a human is about 20-25 mg. It is therefore more toxic to humans than other toxins such as strychnine . In humans, non-lethal amounts produced agitation, drowsiness, and changes in the gastrointestinal tract, and in animals such as mice also agitation, convulsions, and effects on height growth.
Picrotoxinin acts as a non-competitive GABA A receptor - antagonist . Since GABA (γ-aminobutyric acid) is an inhibitory neurotransmitter , picrotoxinin has a stimulative effect. Picrotoxin was previously used as an antidote for barbiturate poisoning. Picrotoxin is a new treatment option for Menière's disease . Picrotoxin poisoning is treated with diazepam and, if necessary, barbiturates such as phenobarbital .
literature
- Dupont, L .; Dideberg, O .; Lamotte-Brasseur, J .; Angenot, L .: Structure Cristalline et Moléculaire de la Picrotoxine, C 15 H 16 O 6 · C 15 H 18 O 7 . In: Acta Crystallographica B . 32, No. 11, 1976, pp. 2987-2993. doi : 10.1107 / S0567740876009424 . (in French)
Web links
See also
- The bicuculline of the heart flowers and the synthetic active ingredient gabazine are also GABA A receptor antagonists.
- The pharmaceuticals baclofen and muscimol , one of the toxins in the toadstool, are GABA receptor agonists .
Individual evidence
- ↑ a b c d data sheet Picrotoxin from Sigma-Aldrich , accessed on April 20, 2011 ( PDF ).
- ↑ a b c Entry on picrotoxin. In: Römpp Online . Georg Thieme Verlag, accessed on June 16, 2014.
- ↑ a b c Entry on picrotoxin in the ChemIDplus database of the United States National Library of Medicine (NLM)
- ↑ a b Setnikar, I .; Murmann, W .; Magistretti, MJ; Da Re, P .: Amino-methylchromones, Brain Stem Stimulants and Pentobarbital Antagonists . In: Journal of Pharmacology and Experimental Therapeutics . 128, 1960, pp. 176-181. PMID 14445192 .
- ↑ a b c Deichmann, WB: Toxicology of Drugs and Chemicals . Academic Press, New York 1969, p. 476.
- ↑ Weikert, S .; Hoelzl, M .; Scherer, H .: Picrotoxin as a therapeutic agent in M. Menière? . In: Thieme Verlag (ed.): ENT information (congress abstracts) . 84, No. 1, 2005. doi : 10.1055 / s-2005-869101 .
- ↑ Entry on picrotoxinin in the Hazardous Substances Data Bank , accessed on October 27, 2014.