Poisoning by Alkaloids

Poisoning in man falls under one of the three headings accident, suicide, or murder. Of these, accidents and suicides are distressingly common, and murder comparatively rare. In England and Wales during the years 1958-61 there were a total of 1633 cases of accidental poisoning and 3955 suicides by poisoning, but only 6 cases of murder by this means 

The situation is rather different in the East. In the Indian state of Uttar Pradesh for the years 1963 to 1965, out of 1355 cases in which poison was found, no fewer than 450 (33%) were due to alkaloids or substances containing them. This total included opium or morphine 248, datura or atropine 180, aconitine 12, and strychnine or nux vomica 10. Barbiturates only accounted for 73 cases (5.4%) (6). 

In spite of this, however, it must be realized that plants containing alkaloids are responsible for many hundreds of deaths in farm stock every year, and probably in a much larger number of cases for ill health and loss of condition due to the ingestion of such plants in quantities insufficient to cause death or even definite clinical symptoms. 

Alkaloids are not used as sedative drugs in the horse—barbiturates or chloral are usually employed—but codeine and quinine, the latter in contradistinction to its use as a potential stimulant in the horse, have 

giantstriata, although poisonous, is much less toxic than C. spectabilis. 

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Although a computer cannot yet be considered as a normal part of laboratory equipment, most of the toxicological laboratories in Europe and North America are fully equipped for instrumental work. Many hospital laboratories on the other hand do not possess anything more sophisticated than a UV spectrophotometer, while in Asia and Africa, where the majority of cases of poisoning by alkaloids occur, only the simplest equipment is available. In order to be of the widest use, the scheme given below is based on paper and thin-layer chromatography with the help of UV spectrophotometry if it is available. 

The limitations are it cannot be used in the presence of air, oxygen or oxidising and reducing reagents the platinum black deteriorates and must be frequently renewed the platinised surface is readily poisoned by alkaloids, cyanides, arsenic and antimony compounds, and by colloids which are adsorbed on the surface. 

Poisoning by ergot still occurs occasionally in countries where rye is extensively used as a food grain or where ergotised grain is liable to be fed to cattle and methods for its detection have been devised, but interest in the analysis of ergot centres chiefly on the estimation of the active alkaloids in the crude drug or its preparations. The methods used may... 

Muscarine, an alkaloid from certain species of mushrooms, is a muscarinic receptor agonist. The compound has toxicologic importance muscarine poisoning will produce all of the effects that are associated with an overdose of ACh (e.g., bronchocon strict ion, bradycardia, hypotension, excessive salivary and respiratory secretion, and sweating). Poisoning by muscarine is treated with atropine. 

The pyrrolobenzodiazepine-5,11 -diones II have been utilized in asymmetric syntheses of both the cis- and tra i-decahydro-quinoline alkaloids (Schemes 21 and 22). For example, reduction of 100 with 4.4 equiv. of potassium in the presence of 2 equiv. of t-BuOH, followed by protonation of the resulting enolate with NH4CI at —78 °C gave the cA-fused tetra-hydrobenzene derivative 101.Amide-directed hydrogenation of 101 gave the hexahydrobenzene derivative with diastereo-selectivity greater than 99 1. Removal of the chiral auxiliary and adjustment of the oxidation state provided aldehyde 103 which was efficiently converted to the poison frog alkaloid (+)-pumiliotoxin C. 

This group of alkaloids has a pyridone nucleus and generally takes the tetracyclic or tricyclic form. The a for pyridone alkaloids is L-lysine, while the j8, q> and X the same as for other quinolizidine alkaloids. Quinolizidine alkaloids containing the pyridone nucleus are the P from the (—/-sparteine by cleavage of the C4 unit. The first quinolizidine alkaloid with the pyridone nucleus is tricyclic cytisine, which converts to four cyclic alkaloids. In this synthesis the anagyrine, the most poisonous quinolizidine alkaloid with a pyridone nucleus, has its own synthesis pathway. 

Abstract Alkaloids are a special group of secondary compounds and are part of an organism s adaptation mechanism to its living environment. They are not toxic when stored, but become toxic as a result of cell pH change. The defensive function of alkaloids is only secondary, and connected to internal immune and regulation processes. Animal responses to alkaloids are very diverse. Some animals can tolerate alkaloids relatively well, while others are harmed or even poisoned by them. Animal behaviour in relation to alkaloids depends on evolutionary and co-evolutionary factors. Sequestration of alkaloids is connected with these processes. Alkaloids are a part of plant-derived nutrition. A selective toxicity of these compounds in vertebrates is clearly observed. Vertebrates have the capacity to recognize alkaloids. 

The best known example for non-depolarizing type of neuro-muscular blocking agents is the alkaloid D-tubocurarine, which has been used as hunting poison by South American Indians. The sensitivity towards D-tubocurarine varies which makes an individual dosage necessary. 

Atropine is used as an antidote in poisoning by an overdose of a cholinesterase inhibitor (see Chapter 14). It also is used in cases of poisoning from species of mushroom that contain high concentrations of muscarine and related alkaloids (e.g., Clitocybe dealbata). 

Several cyclic imines were reduced with phenylsilane as a reducing agent in the presence of the chiral titanocene catalyst 11 followed by a workup process to give the corresponding cyclic amines in excellent ee [26]. The hydrosilylation of 2-propyl-3,4,5,6-tetrahydropyridine with (R)-ll (substrate Ti=100 l) in THF at room temperature was completed in about 6 h (Scheme 14) [29]. The reaction mixture was treated with an acid and then with an aqueous base to afford (S)-coniine, the poisonous hemlock alkaloid, in 99% ee. 

During the reaction silver(0) deposits on the sides of the reaction vessel. The sequence of events leading to the azomethine ylide is unclear. However, evidently single-electron transfer (SET) from the amine to silver takes place either prior or subsequent to fluoride-enabled silyl cleavage. This process is repeated with a second equivalent of silver fluoride resulting in the formation of 38 either in free form or more likely as its silver complex. The scope of the method was expanded to the synthesis of bicylic systems exemplified here by tropinone 42 (Scheme 2.11).19 Pandey has also extended the protocol to the synthesis of tricycloalkanes20 and applied it to a total synthesis of the poisonous frog alkaloid epibatidine.21... 

SAFETY PROFILE Poison by subcutaneous and intraperitoneal routes. Moderately toxic by ingestion. Questionable carcinogen with experimental neoplastigenic data. It mimics the action of acetylcholine, a neurotransmitter, and is a parasympathetic nervous system stimulant. Its action on the central nervous system can cause tremors. Human mutation data reported. It is easily nitrosated to several nitrosamines. See also ESTERS and NITROSAMINES. It is the major alkaloid found in betel quid. Combustible, can react with oxidizing materials. When heated to decomposition it emits highly toxic fumes of NOx. 

DOT CLASSIFICATION 6.1 Label Poison SAFETY PROFILE A poison by subcutaneous, intravenous, and intraperitoneal routes. An alkaloid-like strychnine, but one-sixth as toxic. When heated to decomposition it emits toxic fumes of NOx. See also STRYCHNINE. 

SAFETY PROFILE A human poison by subcutaneous route. Poison experimentally by ingestion, intravenous, intraperitoneal, and subcutaneous routes. A very poisonous alkaloid that is used to remove excess fluid accumulations from the body. Its action on the sweat glands makes it a powerful sudorific. It very rarely causes death, but, when it does, it is by paralysis of the heart or edema of the lungs. Dangerous on heating to decomposition it emits toxic fumes of NO.. 

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