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2-Picoline
2-Methylpyridine, or 2-picoline, is the compound described with formula C6H7N. 2-Picoline is a colorless liquid that has an unpleasant odor similar to pyridine. It is mainly used to make vinylpyridine and the agrichemical nitrapyrin. Synthesis 2-Picoline was the first pyridine compound reported to be isolated in pure form. It was isolated from coal tar in 1846 by T. Anderson. This chemistry was practiced by Reilly Industries. It is now mainly produced by two principal routes. One method involves the condensation of acetaldehyde and ammonia in the presence of an oxide catalyst. This method affords a mixture of 2- and 4-picolines: : Another method involves the condensation of acetone and acrylonitrile to give 5-oxohexanenitrile, which then cyclizes to give 2-picoline. Approximately 8000 t/a was produced worldwide in 1989. Reactions Most of the reactions of picoline are centered on the methyl group. For example, the principal use of 2-picoline is as a precursor of 2-vinylpyrid ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Nitrapyrin
Nitrapyrin is an organic compound with the formula ClC5H3NCCl3, and is described as a white crystalline solid with a sweet odor.It is used as a nitrification inhibitor and bactericide, which is applied to soils for the growing of agricultural crops since 1974. Nitrapyrin was put up for review by the EPA and deemed safe for use in 2005. Nitrapyrin is an effective nitrification inhibitor to the bacteria ''Nitrosomonas'' and has been shown to drastically the reduce the amount of N2O emissions from the soil. Synthesis Nitrapyrin is commonly produced by the photochlorination of 2-methylpyridine: :CH3-C5H4N + 4Cl2 → CCl3-ClC5H3N + 4 HCl Function Nitrapyrin affects the ammonia monooxygenase (AMO) pathway, which is important for NH3 oxidation in nitrification; it also functions as an inhibitor of the urease enzyme in the nitrifying bacteria Nitrosomonas, preventing hydrolytic action on urea.JHG Slangen, P. Kerkhoff; Nitrification Inhibitors in Agriculture and Horticulture: A Liter ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Acetaldehyde
Acetaldehyde (IUPAC systematic name ethanal) is an organic chemical compound with the formula CH3 CHO, sometimes abbreviated by chemists as MeCHO (Me = methyl). 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 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. The International Agency for Research on Cancer (IARC) has listed acetaldehyde as a Group 1 carcinogen. Acetaldehyde is "one of the mos ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Unpleasant Odor
An odor (American English) or odour (Commonwealth English; see spelling differences) is caused by one or more volatilized chemical compounds that are generally found in low concentrations that humans and animals can perceive via their sense of smell. An odor is also called a "smell" or a "scent", which can refer to either a pleasant or an unpleasant odor. While "odor" and "smell" can refer to pleasant and unpleasant odors, the terms "scent", "aroma", and "fragrance" are usually reserved for pleasant-smelling odors and are frequently used in the food and cosmetic industry to describe floral scents or to refer to perfumes. Physiology of smell Sense of smell The perception of odors, or sense of smell, is mediated by the olfactory nerve. The olfactory receptor (OR) cells are neurons present in the olfactory epithelium, which is a small patch of tissue at the back of the nasal cavity. There are millions of olfactory receptor neurons that act as sensory signaling cells. E ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Picolinic Acid
Picolinic acid is an organic compound with the formula C5H4N(CO2H). It is a derivative of pyridine with a carboxylic acid (COOH) substituent at the 2-position. It is an isomer of nicotinic acid and isonicotinic acid, which have the carboxyl side chain at the 3- and 4-position, respectively. It is a white solid that is soluble in water. In synthetic organic chemistry, has been used as a substrate in the Mitsunobu reaction and in the Hammick reaction. Coordination chemistry Picolinic acid is a bidentate chelating agent of elements such as chromium, zinc, manganese, copper, iron, and molybdenum in the human body. Many of its complexes are charge-neutral and thus lipophilic. After its role in absorption was discovered, zinc picolinate dietary supplements became popular as they were shown to be an effective means of introducing zinc into the body. Production Picolinic acid is formed from 2-methylpyridine by oxidation, e.g. by means of potassium permanganate (KMnO4). : Biosynthesi ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
LD50
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 toxin, radiation, or pathogen. 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 increased toxicity. 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 as the mass of substance administered per unit ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Encainide
Encainide (trade name Enkaid) is a class Ic antiarrhythmic agent. It is no longer used because of its frequent proarrhythmic side effects. Synthesis See also * Iferanserin * Cardiac Arrhythmia Suppression Trial The Cardiac Arrhythmia Suppression Trial (CAST) was a double-blind, randomized, controlled study designed to test the hypothesis that suppression of premature ventricular complexes (PVC) with class I antiarrhythmic agents after a myocardial infarc ... References Antiarrhythmic agents Benzanilides Phenol ethers Piperidines Sodium channel blockers Withdrawn drugs {{cardiovascular-drug-stub ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Dimethindene
Dimetindene , also sold under the brand name Fenistil, is an antihistamine/anticholinergic. It is a first generation selective H1 antagonist. Dimetindene is an atypical first generation H1 antagonist as it only minimally passes across the blood–brain barrier. Dimetindene is also an M2 receptor antagonist. It was patented in 1958 and came into medical use in 1960. Medical use Dimetindene is used orally and topically as an antipruritic. It is used topically to treat skin irritations, such as insect bites. Dimetindene is also administered orally to treat allergies, such as hay fever. It is commonly formulated as its maleic acid salt, dimethindene maleate. Names It is sold under the brand name Fenistil Fenistil is a brand name for some over the counter medications distributed by GlaxoSmithKline and Novartis. Products include: * Fenistil Gel, containing dimetindene * Fenistil Cold Sore Cream, containing penciclovir * FeniHydrocort, containing cort ... among others. Refe ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Picoplatin
Picoplatin is a platinum-based antineoplastic agent in clinical development by Poniard Pharmaceuticals (previously NeoRx) for the treatment of patients with solid tumors. In Phase I and Phase II clinical trials, picoplatin demonstrated activity in a variety of solid tumors, including lung, ovarian, colorectal and hormone-refractory prostate cancer. However, in Phase III trials, picoplatin failed to hit its primary endpoint for advanced small cell lung cancer. Hopes are now pinned on its use for metastatic colorectal cancer Colorectal cancer (CRC), also known as bowel cancer, colon cancer, or rectal cancer, is the development of cancer from the colon or rectum (parts of the large intestine). Signs and symptoms may include blood in the stool, a change in bowel m ....http://www.genengnews.com/specialreports/sritem.aspx?oid=69418732 Nov 2009 References Platinum(II) compounds Organochlorides Pyridines Platinum-based antineoplastic agents {{antineoplastic-drug-s ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Amprolium
Amprolium is the organic compound sold as a coccidiostat used in poultry. It has many International Nonproprietary Names. __TOC__ Uses in coccidiosis treatment in poultry The drug is a thiamine analogue and blocks the thiamine transporter of ''Eimeria'' species. By blocking thiamine uptake it prevents carbohydrate synthesis. Despite only moderate efficacy it is well favoured due to few resistance issues and is commonly used in the United States in conjunction with sulfonamides prophylactically in chickens and cattle as a coccidiostat. Synthesis Condensation of ethoxymethylenemalononitrile (1) with acetamidine (2) affords the substituted pyrimidine (4). The reaction may well involve conjugate addition of the amidine nitrogen to the malononitrile followed by loss of ethoxide (3); addition of the remaining amidine nitrogen to one of the nitriles will then lead to the pyrimidine (4). Reduction of the nitrile gives the corresponding aminomethyl compound (5). Exhaustive methylatio ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Actinomycetota
The ''Actinomycetota'' (or ''Actinobacteria'') are a phylum of all gram-positive bacteria. They can be terrestrial or aquatic. They are of great economic importance to humans because agriculture and forests depend on their contributions to soil systems. In soil they help to decompose the organic matter of dead organisms so the molecules can be taken up anew by plants. While this role is also played by fungi, ''Actinomycetota'' are much smaller and likely do not occupy the same ecological niche. In this role the colonies often grow extensive mycelia, like a fungus would, and the name of an important order of the phylum, '' Actinomycetales'' (the actinomycetes), reflects that they were long believed to be fungi. Some soil actinomycetota (such as ''Frankia'') live symbiotically with the plants whose roots pervade the soil, fixing nitrogen for the plants in exchange for access to some of the plant's saccharides. Other species, such as many members of the genus '' Mycobacterium'', ar ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Arthrobacter
''Arthrobacter'' (from the Greek, "jointed small stick”) is a genus of bacteria that is commonly found in soil. All species in this genus are Gram-positive obligate aerobes that are rods during exponential growth and cocci in their stationary phase. ''Arthrobacter'' have a distinctive method of cell division called "snapping division" or reversion in which the outer bacterial cell wall ruptures at a joint. Description ''Arthrobacter'' can be grown on mineral salts pyridone broth, where colonies have a greenish metallic center on incubated at . Under the microscope, ''Arthrobacter'' appear as rods when rapidly dividing, and cocci when in stationary phase. Dividing cells may also appear as chevrons ("V" shapes). Other notable characteristics are that it can use pyridone as its sole carbon source, and that its cocci are resistant to desiccation and starvation. Use in industry ''Arthrobacter'', like other bacterial genera including ''Brevibacterium'', ''Microbacterium'', and '' ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Butyllithium
Butyllithium may refer to one of 5 isomeric organolithium reagents of which 3 are commonly used in chemical synthesis: * ''n''-Butyllithium, abbreviated BuLi or nBuLi * ''sec''-Butyllithium, abbreviated ''sec''-BuLi or sBuLi, has 2 stereoisomers, but is commonly used as racemate *isobutyllithium * ''tert''-Butyllithium, abbreviated ''tert''-BuLi or tBuLi {{Chemistry index ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
