Toxicity of strychnine

Sterner, R. T., Pedersen, C. A., Helsten, B. R. and Goodall, M. J. 1998. Subchronic dietary toxicity of strychnine Bobwhite quail are less sensitive than mallard ducks. Archives of Environmental Contamination and Toxicology, 35 498-505. 

Seidl, I., Zbinden, G. (1982). Subchronic oral toxicity of strychnine in rats. Arch. Toxicol. 51 267-71. 

Toxicity of strychnine varies by sex in rats. Twenty-eight day feeding studies showed that males were able to tolerate up to 8 mg kg day without adverse effects females were able to tolerate 2.5 mgkg day . ... 

Brucine has only one-tenth of the toxicity of strychnine and poisoning by it is very rare. If it is met with in addition to strychnine in a toxicological analysis, it suggests that poisoning has been due to some preparation of nux vomica and not to the pure alkaloid. 

Brucine 2,3-dimethoxystrychnine, M, 394.47, m.p. 105 °C (tetrahydrate), 178 °C (anhydrous). It is used in preparative chemistry to separate racemic acids into optical isomers. B. has one tenth of the toxicity of strychnine, from which it is derived. The main physiological effect is paralysis of smooth musculature. For formula and biosynthesis, see Strychnos alkaloids. 

Toxicity of strychnine in humans, expressed as LDlo (lethal dose low), is approximately 30 mg/kg. Strychnine... 

Tests with animals have revealed that dioxin is one of the most toxic substances known Toward mice it IS about 2000 times more toxic than strychnine and about 150 000 times more toxic than sodium cyanide Fortunately however available evidence in dicates that humans are far more resistant to dioxin than are test animals and so far there have been no human fatalities directly attributable to dioxin The most prominent short term symptom seen so far has been a severe skin disorder known as chloracne Yet to be determined is the answer to the question of... 

A comparative investigation has been made by Amanii et al. of strychnine and some of its derivatives for toxicity, taking strychnine nitrate as standard and equal to 1. The following results were obtained —... 

Paquin in 1948 found that a strongly exothermic reaction occurred when 40% formaldehyde was added to a solution of sulfamide in 25% aqueous ammonia. At once beautiful crystals precipitated they were recrystallized from 96% alcohol to give a compound, C5H10N4SO2, mp 224-225 "C, in 88% yield.245 From the similar character to hexamethylenetetramine, he named this product pentamethylenetetramine sulfone it is 225. One year later, in 1949, Hecht and Henecka at Bayer research laboratory reported that a condensation product from one mole of sulfamide in strong mineral acid and two moles of formaldehyde showed very strong toxicity and was five times more toxic than strychnine. They called this product (226) tetra-methylenedisulfotetramine. 246... 

So, in a way, it is with quinine, known (29) since antiquity as a potent antimalarial. For chemists, the use of quinicine in 1854 in the first resolution of a racemate (1,3) marks a milestone Stereochemistry as we know it today made its debut in that year. In resolutions, quinine and its diastereomers proved to be safe to handle (compare the extreme toxicity of brucine or strychnine with that of quinine), versatile in their applications, and available in reasonably pure form. Little wonder that even today, 131 years after its first use as a resolving agent, quinine (and brucine) continues to be the chemical of choice when one is attempting a new resolution of a racemic acid (90). 

Many birds such as sparrows, blackbirds, rice birds, grackles, and cowbirds can cause heavy loss of grain in rice fields. Because the use of poisoned baits in some countries is often restricted by law or popular opinion, the information presented does not constitute a recommendation on any specific chemical. The use of strychnine-poisoned rough rice (17, 18, 25) against blackbirds, grackles, cowbirds, and English sparrows, wherever the use of poison is permitted, can be effective. Many other toxic chemicals will kill these birds however, domestic poultry and game bird species are relatively much less susceptible to strychnine than to other toxic materials. Therefore, we have in strychnine a fairly effective selectivity which other toxic materials do not offer. 

Strychnine and brucine are extremely toxic alkaloids. Strychnine binds itself to receptor sites in the spinal cord and accommodates glycine. Brucine is a dimethoxy form of strychnine, and is less toxic. 

One of the most known toxic alkaloid is strychnine. Vanderkop" and Sterner et aU are examples of those who have studied its toxicity, although it is practically rather evident. This alkaloid has been used as a strong rodenticide. It is also known for being dangerous to humans. One general characteristic of strychnine is its chemical stability. This is some kind of exception in the alkaloids, which are generally flexible heterogeneous compounds. In cases of... 

Today the toxic effect of silatranes has been thoroughly studied1-3,16-44a b The toxicity of silatranes varies greatly and is mainly dependent on the nature of substituents at the silicon atom. Most toxic of all known silatranes are 1-arylsila-tranes, 4-XC6H4Si(OCH2CH2)3N, where X = CH3, Cl, H (Table 1). These compounds are almost twice as toxic as such well-known poisons as strychnine and hydrocyanic acid. They produce an intensive stimulation of the motor and respiratory centres1-3,30-34,44,when administered at lower than lethal doses... 

Although Dendrobium species are much better known as ornamental plants and for their use in traditional medicine, their alkaloids, the dendrobines, are also convulsants (2). The effects of dendrobinium chloride intoxication resemble more those of strychnine intoxication than those of picrotoxinin intoxication (240). The minimal lethal dose (intravenous) in rats and mice is 20 mg/kg. The toxicity of the picrotoxanes is attributable to their ability to overcome the blood-brain barrier and to bind to inhibitory Cys-loop receptors of the postS3napses of the CNS. 

Strychnine was discovered and identified as the main toxic principle of Strychnos in 1818, although nux vomica, the unpurified plant extract in which it is the active component, had been known and used for both medicinal and criminal purposes for some time. Historic records indicate that the strychnine alkaloid had been used to kill dogs, cats, and birds in Emope as far back as 1640. The structure of strychnine was first determined in 1946 by Sir Robert Robinson and in 1954 this alkaloid was synthesized in a laboratory by Robert W. Woodward. This is one of the most famous syntheses in the history of organic chemistry. Both chemists won the Nobel prize (Robinson in 1947 and Woodward in 1965). 

Reported toxic doses of strychnine by different routes of adinistration in some animals and humans are summarized in Table 14.1. 

TABLE 14.1. Toxicity values (LDgo) of strychnine in humans and animals... 

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