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Chloral
Chloral, also known as trichloroacetaldehyde or trichloroethanal, is the organic compound with the formula Cl3CCHO. This aldehyde is a colourless liquid that is soluble in a wide range of solvents. It reacts with water to form chloral hydrate, a once widely used sedative and hypnotic substance. Production Chloral was first prepared, and named, by the German chemist Justus von Liebig in 1832. Liebig treated anhydrous ethanol with dry chlorine gas. Chloral is produced commercially by the chlorination of acetaldehyde in the presence of hydrochloric acid, producing chloral hydrate. Ethanol can also be used as a feedstock. This reaction is catalyzed by antimony trichloride: :H3CCHO + 3 Cl2 + H2O → Cl3CCH(OH)2 + 3 HCl The chloral hydrate is distilled from the reaction mixture. The distillate is then dehydrated with concentrated sulfuric acid, after which the heavier acid layer (containing the water) is drawn off: :Cl3CCH(OH)2 → Cl3CCHO + H2O The resulting product is p ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Chloral Hydrate
Chloral hydrate is a geminal diol with the formula . It was first used as a sedative and hypnotic in Germany in the 1870s. Over time it was replaced by safer and more effective alternatives but it remained in use in the United States until at least the 1970s. It sometimes finds usage as a laboratory chemical reagent and precursor. It is derived from chloral (trichloroacetaldehyde) by the addition of one equivalent of water. Uses Hypnotic Chloral hydrate has not been approved by the FDA in the United States nor the EMA in the European Union for any medical indication and is on the FDA list of unapproved drugs that are still prescribed by clinicians. Usage of the drug as a sedative or hypnotic may carry some risk given the lack of clinical trials. However, chloral hydrate products, licensed for short-term management of severe insomnia, are available in the United Kingdom. Chloral hydrate was voluntarily removed from the market by all manufacturers in the United States in 20 ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Chloral Cyanohydrin
Chloral cyanohydrin is the cyanohydrin derivative of chloral (trichloroacetaldehyde). It was historically used as a source of hydrogen cyanide for medicinal purposes. Chloral cyanohydrin is toxic by inhalation. See also *Chloral hydrate Chloral hydrate is a geminal diol with the formula . It was first used as a sedative and hypnotic in Germany in the 1870s. Over time it was replaced by safer and more effective alternatives but it remained in use in the United States until at ... References Blood agents Cyanohydrins Trichloromethyl compounds {{Organohalide-stub ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Bromal
Bromal (tribromoacetaldehyde) is a brominated aldehyde. It reacts with water to form bromal hydrate. See also *Chloral *Chloral hydrate Chloral hydrate is a geminal diol with the formula . It was first used as a sedative and hypnotic in Germany in the 1870s. Over time it was replaced by safer and more effective alternatives but it remained in use in the United States until at ... References Aldehydes Tribromomethyl compounds {{Organohalide-stub ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Fluoral
Trifluoroacetaldehyde, trifluoroethanal, or fluoral,''Trifluoroacetaldehyde'', Peter Lin (2003)DOI:10.1002/047084289X.RN00213/ref> is a fluorinated derivative of acetaldehyde with the formula . It is a gas at room temperature. Fluoral is used to introduce trifluoromethyl groups into organic compounds.''2. Aldehydes'', Fluorocarbon and Related Chemistry: Volume 2 (2007) Royal Society of Chemistry. It is highly electrophilic and fluoral forms a hydrate upon contact with water like other halogenated acetaldehydes.Kitazume, T., Yamazaki, T. (2019). Experimental Methods in Organic Fluorine Chemistry It is commonly used in form of ethyl hemiacetal (1-ethoxy-2,2,2-trifluoroethanol, ) due to the aldehyde's high reactivity, including the tendency to polymerise.''Trifluoroacetaldehyde: A useful industrial bulk material for the synthesis of trifluoromethylated amino compounds'', Hideyuki Mimura, Kosuke Kawada, Tetsuya Yamashita, Takeshi Sakamoto, Yasuo Kikugawa. Journal of Fluorine Che ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Sodium Hydroxide
Sodium hydroxide, also known as lye and caustic soda, is an inorganic compound with the formula . It is a white solid ionic compound consisting of sodium cations and hydroxide anions . Sodium hydroxide is a highly corrosive base (chemistry), base and alkali that decomposes lipids and proteins at ambient temperatures and at high concentrations may cause severe chemical burns. It is highly soluble in water, and readily absorbs moisture and carbon dioxide from the air. It forms a series of hydrates . The monohydrate crystallizes from water solutions between 12.3 and 61.8 °C. The commercially available "sodium hydroxide" is often this monohydrate, and published data may refer to it instead of the anhydrous compound. As one of the simplest hydroxides, sodium hydroxide is frequently used alongside neutral water and acidic hydrochloric acid to demonstrate the pH scale to chemistry students. Sodium hydroxide is used in many industries: in the making of wood pulp and paper, tex ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
IARC Group 2A Carcinogens
IARC group 2A agents are substances and exposure circumstances that have been classified as probable carcinogens by the International Agency for Research on Cancer (IARC). This designation is applied when there is limited evidence of carcinogenicity in humans, as well as ''sufficient evidence'' of carcinogenicity in experimental animals. In some cases, an agent may be classified in this group when there is ''inadequate evidence'' of carcinogenicity in humans along with ''sufficient evidence'' of carcinogenicity in experimental animals and ''strong evidence'' that the carcinogenesis is mediated by a mechanism that also operates in humans. Exceptionally, an agent may be classified in this group solely on the basis of ''limited evidence'' of carcinogenicity in humans. This list is focusing on the hazard linked to the agents. This means that the carcinogenic agents are capable of causing cancer, but this does not take their risk into account, which is the probability of causing a can ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Sedative
A sedative or tranquilliser is a substance that induces sedation by reducing irritability or Psychomotor agitation, excitement. They are central nervous system (CNS) Depressant, depressants and interact with brain activity, causing its deceleration. Various kinds of sedatives can be distinguished, but the majority of them affect the neurotransmitter Gamma-Aminobutyric acid, gamma-aminobutyric acid (GABA). Most sedatives produce relaxing effects by increasing GABA activity. This group is related to hypnotics. The term ''sedative'' describes drugs that serve to calm or Anxiolytic, relieve anxiety, whereas the term ''hypnotic'' describes drugs whose main purpose is to initiate, sustain, or lengthen sleep. Because these two functions frequently overlap, and because drugs in this class generally produce dose-dependent effects (ranging from anxiolysis to loss of consciousness), they are often referred to collectively as ''sedative–hypnotic'' drugs. Terminology There is some overlap ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
GABAA Receptor Positive Allosteric Modulators
In pharmacology, GABAA receptor positive allosteric modulators, also known as GABAkines or GABAA receptor potentiators, are positive allosteric modulator (PAM) molecules that increase the activity of the GABAA receptor, GABAA receptor protein in the vertebrate central nervous system. GABA is a major inhibitory neurotransmitter in the central nervous system. Upon binding, it Agonist, triggers the GABAA receptor to open its GABAA receptor#Structure and function, chloride channel to allow Chloride, chloride ions into the neuron, making the cell Hyperpolarization (biology), hyperpolarized and less likely to Action potential, fire. GABAA PAMs increase the effect of GABA by making the channel open more frequently or for longer periods. However, they have no effect if GABA or another agonist is not present. Unlike GABA receptor agonist, GABAA receptor agonists, GABAA PAMs do not bind at the same active site as the γ-aminobutyric acid (GABA) neurotransmitter molecule: they affect the r ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Othmar Zeidler
Othmar Zeidler (29 August 1850 – 17 June 1911)Though many sources mention 1859 as Zeidler's year of birth, this would make him a mere 14 years old at the time of his dissertation in 1873. The 1859 birth yeawas usedby Joseph S. Fruton, in his ''Contrasts in scientific style: research groups in the chemical and biochemical sciences'', Memoirs of the American Philosophical Society, Vol 191, 1990, p. 373, as well as by Gerhard Oberkofler in ''Leopold Ruzicka, 1887–1976: schweizer Chemiker und Humanist aus Altösterreich'', p. 44. The latter even has him quit his pharmacy studies at the Vienna University in 1872 (at the apparent age of 12/13) to move to Strassburg. However, ''Materialien zur Geschichte der Apotheken und Apotheker Niederösterreichs'' gives his year of birth as 1850; furthermore, his obituary at ''Oesterreichische Chemiker–Zeitung'' in 1911 states that Zeidler was 61 years at the time of his death, placing his birth around 1850 (in reality, Zeidler died 2 months sh ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Justus Von Liebig
Justus ''Freiherr'' von Liebig (12 May 1803 – 18 April 1873) was a Germans, German scientist who made major contributions to the theory, practice, and pedagogy of chemistry, as well as to agricultural and biology, biological chemistry; he is considered one of the principal founders of organic chemistry. As a professor at the University of Giessen, he devised the modern laboratory-oriented teaching method, and for such innovations, he is regarded as one of the most outstanding chemistry teachers of all time. He has been described as the "father of the fertilizer industry" for his emphasis on nitrogen and minerals as essential plant nutrients, and his popularization of the law of the minimum, which states that plant growth is limited by the scarcest nutrient resource, rather than the total amount of resources available. He also developed a manufacturing process for Meat extract, beef extracts, and with his consent a company, called Liebig Extract of Meat Company, was founded to e ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Acetaldehyde
Acetaldehyde (IUPAC systematic name ethanal) is an organic compound, organic chemical compound with the chemical formula, formula , sometimes abbreviated as . It is a colorless liquid or gas, boiling near room temperature. It is one of the most important aldehydes, occurring widely in nature and being produced on a large scale in industry. Acetaldehyde occurs naturally in coffee, bread, and ripe fruit, and is produced by plants. It is also produced by the partial oxidation of ethanol by the liver enzyme alcohol dehydrogenase and is a contributing cause of hangover after alcohol (drug), alcohol consumption. Pathways of exposure include air, water, land, or groundwater, as well as drink and smoke. Consumption of disulfiram inhibits acetaldehyde dehydrogenase, the enzyme responsible for the metabolism of acetaldehyde, thereby causing it to build up in the body. International Agency for Research on Cancer, The International Agency for Research on Cancer (IARC) has listed acetaldehyde ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
LC50
In toxicology, the median lethal dose, LD50 (abbreviation for "lethal dose, 50%"), LC50 (lethal concentration, 50%) or LCt50 is a toxic unit that measures the lethal dose of a given substance. The value of LD50 for a substance is the dose required to kill half the members of a tested population after a specified test duration. LD50 figures are frequently used as a general indicator of a substance's acute toxicity. A lower LD50 is indicative of higher toxicity. The term LD50 is generally attributed to John William Trevan. The test was created by J. W. Trevan in 1927. The term semilethal dose is occasionally used in the same sense, in particular with translations of foreign language text, but can also refer to a sublethal dose. LD50 is usually determined by tests on animals such as laboratory mice. In 2011, the U.S. Food and Drug Administration approved alternative methods to LD50 for testing the cosmetic drug botox without animal tests. Conventions The LD50 is usually expressed ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
