|
Piperidines
Piperidine is an organic compound with the molecular formula (CH2)5NH. This heterocyclic amine consists of a six-membered ring containing five methylene bridges (–CH2–) and one amine bridge (–NH–). It is a colorless liquid with an odor described as objectionable, and typical of amines. The name comes from the genus name ''Piper'', which is the Latin word for pepper. Although piperidine is a common organic compound, it is best known as a representative structure element within many pharmaceuticals and alkaloids, such as natural-occurring solenopsins. Production Piperidine was first reported in 1850 by the Scottish chemist Thomas Anderson and again, independently, in 1852 by the French chemist Auguste Cahours, who named it. Both of them obtained piperidine by reacting piperine with nitric acid. Industrially, piperidine is produced by the hydrogenation of pyridine, usually over a molybdenum disulfide catalyst: : C5H5N + 3 H2 → C5H10NH Pyridine can also be reduce ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Royal Society Of Chemistry
The Royal Society of Chemistry (RSC) is a learned society (professional association) in the United Kingdom with the goal of "advancing the chemistry, chemical sciences". It was formed in 1980 from the amalgamation of the Chemical Society, the Royal Institute of Chemistry, the Faraday Society, and the Society for Analytical Chemistry with a new Royal Charter and the dual role of learned society and professional body. At its inception, the Society had a combined membership of 34,000 in the UK and a further 8,000 abroad. The headquarters of the Society are at Burlington House, Piccadilly, London. It also has offices in Thomas Graham House in Cambridge (named after Thomas Graham (chemist), Thomas Graham, the first president of the Chemical Society) where ''RSC Publishing'' is based. The Society has offices in the United States, on the campuses of The University of Pennsylvania and Drexel University, at the University City Science Center in Philadelphia, Pennsylvania, in both Beijing a ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Piperine
Piperine, along with its isomer chavicine, is the alkaloid responsible for the pungency of black pepper and long pepper. It has been used in some forms of traditional medicine. Preparation Due to its poor solubility in water, piperine is typically extracted from black pepper by using organic solvents like dichloromethane. The amount of piperine varies from 1–2% in long pepper, to 5–10% in commercial white and black peppers. Piperine can also be prepared by treating a concentrated alcoholic extract of black pepper with an alcoholic solution of potassium hydroxide to remove resin (said to contain chavicine, an isomer of piperine). The solution is decanted from the insoluble residue and left to stand overnight. During this period, the alkaloid slowly crystallizes from the solution. Piperine has been synthesized by the action of piperonoyl chloride on piperidine. Reactions Piperine forms salts only with strong acids. The platinichloride B4·H2PtCl6 forms orange-red needles ( ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Nicotine
Nicotine is a naturally produced alkaloid in the nightshade family of plants (most predominantly in tobacco and ''Duboisia hopwoodii'') and is widely used recreationally as a stimulant and anxiolytic. As a pharmaceutical drug, it is used for smoking cessation to relieve withdrawal symptoms. Nicotine acts as a receptor agonist at most nicotinic acetylcholine receptors (nAChRs), except at two nicotinic receptor subunits (nAChRα9 and nAChRα10) where it acts as a receptor antagonist. Nicotine constitutes approximately 0.6–3.0% of the dry weight of tobacco. Nicotine is also present at ppb-concentrations in edible plants in the family Solanaceae, including potatoes, tomatoes, and eggplants, though sources disagree on whether this has any biological significance to human consumers. It functions as an antiherbivore toxin; consequently, nicotine was widely used as an insecticide in the past, and neonicotinoids (structurally similar to nicotine), such as imidacloprid, are s ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Solenopsin
Solenopsin is a lipophilic alkaloid with the molecular formula C17H35N found in the venom of fire ants (''Solenopsis''). It is considered the primary toxin in the venom and may be the component responsible for the cardiorespiratory failure in people who experience excessive fire ant stings. Structurally solenopsins are a piperidine ring with a methyl group substitution at position 2 and a long hydrophobic chain at position 6. They are typically oily at room temperature, water-insoluble, and present an absorbance peak at 232 nanometers. Fire ant venom contains other chemically related piperidines which make purification of solenopsin from ants difficult. Therefore, solenopsin and related compounds have been the target of organic synthesis from which pure compounds can be produced for individual study. Originally synthesized in 1993, several groups have designed novel and creative methods of synthesizing enantiopure solenopsin and other alkaloidal components of ant venom. Total ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Fire Ant
Fire ants are several species of ants in the genus ''Solenopsis'', which includes over 200 species. ''Solenopsis'' are stinging ants, and most of their common names reflect this, for example, ginger ants and tropical fire ants. Many of the names shared by this genus are often used interchangeably to refer to other species of ant, such as the term red ant, mostly because of their similar coloration despite not being in the genus Solenopsis. Both ''Myrmica rubra ''Myrmica rubra'', also known as the common red ant or erroneously the European fire ant, is a species of ant of the genus '' Myrmica'', found all over Europe and is now invasive in some parts of North America and Asia. It is mainly red in colou ...'' and ''Pogonomyrmex barbatus'' are common examples of non-Solenopsis ants being termed red ants. None of these names apply to all species of ''Solenopsis'' nor only to ''Solenopsis'' species; for example the colloquial names for several species of weaver ants in the genus ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Petrosimonia Monandra
''Petrosimonia'' is a genus of flowering plants belonging to the family Amaranthaceae. It is also in the Salsoloideae tribe. It is native to Albania, Bulgaria, Greece, Romania (in southeastern Europe), Central European Russia, Crimea South European Russia and Ukraine, (Eastern Europe), Altay, Irkutsk, Tuva and West Siberia, (in Siberia), North Caucasus, Transcaucasus, (in the Caucasus), Kazakhstan, Kyrgyzstan, Tajikistan, Turkmenistan and Uzbekistan (in Central Asia) and Afghanistan, Iran, Lebanon, Mongolia, Syria and Turkey, (in Western Asia) and also Xinjiang in China. The genus name of ''Petrosimonia'' is in honour of Peter Simon Pallas Peter Simon Pallas Fellow of the Royal Society, FRS FRSE (22 September 1741 – 8 September 1811) was a Prussian zoologist and botanist who worked in Russia between 1767 and 1810. Life and work Peter Simon Pallas was born in Berlin, the son ... (1741–1811), a Prussian zoologist and botanist who worked in Russia (1767–1810). It wa ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Aizoaceae
The Aizoaceae, or fig-marigold family, is a large family of dicotyledonous flowering plant Flowering plants are plants that bear flowers and fruits, and form the clade Angiospermae (), commonly called angiosperms. The term "angiosperm" is derived from the Greek words ('container, vessel') and ('seed'), and refers to those plants th ...s containing 135 genus, genera and about 1800 species. They are commonly known as ice plants or carpet weeds. They are often called vygies in South Africa and New Zealand. Highly Succulent plant, succulent species that resemble stones are sometimes called mesembs. Description The family Aizoaceae is widely recognised by taxonomists. It once went by the botanical name "Ficoidaceae", now disallowed. The APG II system of 2003 (unchanged from the APG system of 1998) also recognizes the family, and assigns it to the order Caryophyllales in the clade core eudicots. The APG II system also classes the former families Mesembryanthemaceae Fenzl, S ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Black Pepper
Black pepper (''Piper nigrum'') is a flowering vine in the family Piperaceae, cultivated for its fruit, known as a peppercorn, which is usually dried and used as a spice and seasoning. The fruit is a drupe (stonefruit) which is about in diameter (fresh and fully mature), dark red, and contains a stone which encloses a single pepper seed. Peppercorns and the ground pepper derived from them may be described simply as ''pepper'', or more precisely as ''black pepper'' (cooked and dried unripe fruit), ''green pepper'' (dried unripe fruit), or ''white pepper'' (ripe fruit seeds). Black pepper is native to the Malabar Coast of India, and the Malabar pepper is extensively cultivated there and in other tropical regions. Ground, dried, and cooked peppercorns have been used since antiquity, both for flavour and as a traditional medicine. Black pepper is the world's most traded spice, and is one of the most common spices added to cuisines around the world. Its spiciness is due to the ch ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Ethanol
Ethanol (abbr. EtOH; also called ethyl alcohol, grain alcohol, drinking alcohol, or simply alcohol) is an organic compound. It is an Alcohol (chemistry), alcohol with the chemical formula . Its formula can be also written as or (an ethyl group linked to a hydroxyl group). Ethanol is a Volatility (chemistry), volatile, Combustibility and flammability, flammable, colorless liquid with a characteristic wine-like odor and pungent taste. It is a psychoactive recreational drug, the active ingredient in alcoholic drinks. Ethanol is naturally produced by the fermentation process of Carbohydrate, sugars by yeasts or via Petrochemistry, petrochemical processes such as ethylene hydration. It has medical applications as an antiseptic and disinfectant. It is used as a chemical solvent and in the Chemical synthesis, synthesis of organic compounds, and as a Alcohol fuel, fuel source. Ethanol also can be dehydrated to make ethylene, an important chemical feedstock. As of 2006, world produ ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Sodium
Sodium is a chemical element with the symbol Na (from Latin ''natrium'') and atomic number 11. It is a soft, silvery-white, highly reactive metal. Sodium is an alkali metal, being in group 1 of the periodic table. Its only stable isotope is 23Na. The free metal does not occur in nature, and must be prepared from compounds. Sodium is the sixth most abundant element in the Earth's crust and exists in numerous minerals such as feldspars, sodalite, and halite (NaCl). Many salts of sodium are highly water-soluble: sodium ions have been leached by the action of water from the Earth's minerals over eons, and thus sodium and chlorine are the most common dissolved elements by weight in the oceans. Sodium was first isolated by Humphry Davy in 1807 by the electrolysis of sodium hydroxide. Among many other useful sodium compounds, sodium hydroxide (lye) is used in soap manufacture, and sodium chloride (edible salt) is a de-icing agent and a nutrient for animals including h ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Birch Reduction
The Birch reduction is an organic reaction that is used to convert arenes to cyclohexadienes. The reaction is named after the Australian chemist Arthur Birch and involves the organic reduction of aromatic rings in an amine solvent (traditionally liquid ammonia) with an alkali metal (traditionally sodium) and a proton source (traditionally an alcohol). Unlike catalytic hydrogenation, Birch reduction does not reduce the aromatic ring all the way to a cyclohexane. An example is the reduction of naphthalene in ammonia and ethanol: Reaction mechanism and regioselectivity A solution of sodium in liquid ammonia consists of the intensely blue electride salt a(NH3)xsup>+ e−. The solvated electrons add to the aromatic ring to give a radical anion, which then abstracts a proton from the alcohol. The process then repeats at either the ''ortho'' or ''para'' position (depending on substituents) to give the final diene. The residual double bonds do not stabilize further radical add ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
