Barbital
Encyclopedia
Barbital also called barbitone, was the first commercially marketed barbiturate
. It was used as a sleeping aid (hypnotic
) from 1903 until the mid-1950s. The chemical names for barbital are diethylmalonyl urea or diethylbarbituric acid. Veronal was prepared by condensing diethylmalonic ester with urea
in the presence of sodium ethoxide, and then by adding at least two molar equivalents of ethyl iodide to the silver salt of malonylurea or possibly to a basic solution of the acid. The result was an odorless, slightly bitter, white crystalline powder.
and Joseph von Mering
. They published their discovery in 1903 and it was marketed in 1904 by the Bayer
company as “Veronal”. A soluble salt of barbital was marketed by the Schering
company as “Medinal.” It was dispensed for “insomnia
induced by nervous excitability”. It was provided in either capsules or cachets. The therapeutic dose was ten to fifteen grains
(0.65-0.97 gram
s). 3.5 to 4.4 grams is the deadly dose but sleep has also been prolonged up to ten days with recovery.
Barbital can be synthesized in a condensation reaction
from urea
and a diethyl malonate
derivative:
s. It had few side effects. Its therapeutic dose was far below the toxic dose. However, prolonged usage resulted in tolerance to the drug, requiring higher doses to reach the desired effect. Fatal overdoses of this slow acting hypnotic were not uncommon.
Barbiturate
Barbiturates are drugs that act as central nervous system depressants, and can therefore produce a wide spectrum of effects, from mild sedation to total anesthesia. They are also effective as anxiolytics, as hypnotics, and as anticonvulsants...
. It was used as a sleeping aid (hypnotic
Hypnotic
Hypnotic drugs are a class of psychoactives whose primary function is to induce sleep and to be used in the treatment of insomnia and in surgical anesthesia...
) from 1903 until the mid-1950s. The chemical names for barbital are diethylmalonyl urea or diethylbarbituric acid. Veronal was prepared by condensing diethylmalonic ester with urea
Urea
Urea or carbamide is an organic compound with the chemical formula CO2. The molecule has two —NH2 groups joined by a carbonyl functional group....
in the presence of sodium ethoxide, and then by adding at least two molar equivalents of ethyl iodide to the silver salt of malonylurea or possibly to a basic solution of the acid. The result was an odorless, slightly bitter, white crystalline powder.
Synthesis
Barbital was first synthesized in 1902 by German chemists Emil FischerHermann Emil Fischer
Hermann Emil Fischer, Emil Fischer was a German chemist and 1902 recipient of the Nobel Prize in Chemistry. He discovered the Fischer esterification. He developed the Fischer projection, a symbolic way of drawing asymmetric carbon atoms.-Early years:Fischer was born in Euskirchen, near Cologne,...
and Joseph von Mering
Joseph von Mering
Josef, Baron von Mering was a German physician.Working at the University of Strasbourg, Mering was the first person to discover that one of the pancreatic functions is the production of insulin, a hormone which controls blood sugar levels.Mering was curious about the...
. They published their discovery in 1903 and it was marketed in 1904 by the Bayer
Bayer
Bayer AG is a chemical and pharmaceutical company founded in Barmen , Germany in 1863. It is headquartered in Leverkusen, North Rhine-Westphalia, Germany and well known for its original brand of aspirin.-History:...
company as “Veronal”. A soluble salt of barbital was marketed by the Schering
Schering
Schering AG was a research-centered German pharmaceutical company. It was founded in 1851 by Ernst Christian Friedrich Schering and merged with Bayer's pharma sector in December 2006. The company's headquarters was in Berlin-Wedding, Germany...
company as “Medinal.” It was dispensed for “insomnia
Insomnia
Insomnia is most often defined by an individual's report of sleeping difficulties. While the term is sometimes used in sleep literature to describe a disorder demonstrated by polysomnographic evidence of disturbed sleep, insomnia is often defined as a positive response to either of two questions:...
induced by nervous excitability”. It was provided in either capsules or cachets. The therapeutic dose was ten to fifteen grains
Grain (measure)
A grain is a unit of measurement of mass that is nominally based upon the mass of a single seed of a cereal. From the Bronze Age into the Renaissance the average masses of wheat and barley grains were part of the legal definition of units of mass. However, there is no evidence of any country ever...
(0.65-0.97 gram
Gram
The gram is a metric system unit of mass....
s). 3.5 to 4.4 grams is the deadly dose but sleep has also been prolonged up to ten days with recovery.
Barbital can be synthesized in a condensation reaction
Condensation reaction
A condensation reaction is a chemical reaction in which two molecules or moieties combine to form one single molecule, together with the loss of a small molecule. When this small molecule is water, it is known as a dehydration reaction; other possible small molecules lost are hydrogen chloride,...
from urea
Urea
Urea or carbamide is an organic compound with the chemical formula CO2. The molecule has two —NH2 groups joined by a carbonyl functional group....
and a diethyl malonate
Diethyl malonate
Diethyl malonate, also known as DEM, is the diethyl ester of malonic acid. It occurs naturally in grapes and strawberries as a colourless liquid with an apple-like odour, and is used in perfumes...
derivative:
Pharmacology
Veronal was considered to be a great improvement over the existing hypnotics. Its taste was slightly bitter, but an improvement over the strong, unpleasant taste of the commonly used bromideBromide
A bromide is a chemical compound containing bromide ion, that is bromine atom with effective charge of −1. The class name can include ionic compounds such as caesium bromide or covalent compounds such as sulfur dibromide.-Natural occurrence:...
s. It had few side effects. Its therapeutic dose was far below the toxic dose. However, prolonged usage resulted in tolerance to the drug, requiring higher doses to reach the desired effect. Fatal overdoses of this slow acting hypnotic were not uncommon.