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Santonin
Santonin is a drug which was widely used in the past as an anthelminthic. It is a terpenoid and an organic compound consisting of colorless flat prisms, turning slightly yellow from the action of light and soluble in alcohol, chloroform and boiling water. According to the ''US Pharmacopoeia'', santonin occurs "in colorless, shining, flattened, prismatic crystals, odorless and nearly tasteless when first put in the mouth, but afterward developing a bitter taste; not altered by exposure to air, but turning yellow on exposure to light. Nearly insoluble in cold water; soluble in 40 parts of alcohol at 15 °C. (59 °F.), in 250 parts of boiling water, and in 8 parts of boiling alcohol; also soluble in 140 parts of ether, in 4 parts of chloroform, and in solutions of caustic alkalies. When heated to 170 °C. (338 °F.), santonin melts, and forms, if rapidly cooled, an amorphous mass, which instantly crystallizes oil coming in contact with a minute quantity of one of ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Santonin Biosynth
Santonin is a drug which was widely used in the past as an anthelminthic. It is a terpenoid and an organic compound consisting of colorless flat prisms, turning slightly yellow from the action of light and soluble in alcohol, chloroform and boiling water. According to the ''US Pharmacopoeia'', santonin occurs "in colorless, shining, flattened, prismatic crystals, odorless and nearly tasteless when first put in the mouth, but afterward developing a bitter taste; not altered by exposure to air, but turning yellow on exposure to light. Nearly insoluble in cold water; soluble in 40 parts of alcohol at 15 °C. (59 °F.), in 250 parts of boiling water, and in 8 parts of boiling alcohol; also soluble in 140 parts of ether, in 4 parts of chloroform, and in solutions of caustic alkalies. When heated to 170 °C. (338 °F.), santonin melts, and forms, if rapidly cooled, an amorphous mass, which instantly crystallizes oil coming in contact with a minute quantity of one of ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Anthelminthic
Anthelmintics or antihelminthics are a group of antiparasitic drugs that expel parasitic worms (helminths) and other internal parasites from the body by either stunning or killing them without causing significant damage to the host. They may also be called vermifuges (those that stun) or vermicides (those that kill). Anthelmintics are used to treat people who are infected by helminths, a condition called helminthiasis. These drugs are also used to treat infected animals, particularly small ruminants such as goats and sheep. Anthelmintic medication is also used in mass deworming campaigns of school-aged children in many developing countries. Anthelmintics are also used for mass deworming of livestock. The drugs of choice for soil-transmitted helminths are mebendazole and albendazole; for schistosomiasis and tapeworms it is praziquantel. Types Many early treatments were herbal, such as the oil of herbs of the genus ''Chenopodium'' that were given as anthelmintic treatment for centu ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Ascaricide
Ascaricides are drugs to treat ascariasis that is caused by infections with parasitic nematodes (''roundworms'') of the genus ''Ascaris'' (''giant intestinal roundworms''). The large roundworm of pigs (''Ascaris suum'') typically infects pigs while ''Ascaris lumbricoides'' affects human populations, typically in sub-tropical and tropical areas with poor sanitation. Ascaricides belong to the group of drugs collectively called anthelmintics which expel parasitic worms (helminths) and other internal parasites from the body by either stunning or killing them and without causing significant damage to the host. Types Common ascaricides include: * Mebendazole (Vermox), causes slow immobilization and death of the worms by selectively and irreversibly blocking uptake of glucose and other nutrients in susceptible adult intestine where helminths dwell. Oral dosage is 100 mg every 12 hours for 3 days. * Piperazine, a flaccid paralyzing agent that causes a blocking response of ascaris muscl ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Hydrolysis
Hydrolysis (; ) is any chemical reaction in which a molecule of water breaks one or more chemical bonds. The term is used broadly for substitution reaction, substitution, elimination reaction, elimination, and solvation reactions in which water is the nucleophile. Biological hydrolysis is the cleavage of Biomolecule, biomolecules where a water molecule is consumed to effect the separation of a larger molecule into component parts. When a carbohydrate is broken into its component sugar molecules by hydrolysis (e.g., sucrose being broken down into glucose and fructose), this is recognized as saccharification. Hydrolysis reactions can be the reverse of a condensation reaction in which two molecules join into a larger one and eject a water molecule. Thus hydrolysis adds water to break down, whereas condensation builds up by removing water. Types Usually hydrolysis is a chemical process in which a molecule of water is added to a substance. Sometimes this addition causes both the su ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Germacrene
Germacrenes are a group of five naturally occurring volatile organic hydrocarbons of the sesquiterpene and cycloalkene class. Germacrenes are typically produced in a number of plant species for their antimicrobial and insecticidal properties, though they also play a role as insect pheromones. Two prominent molecules are germacrene A and germacrene D. Structures Germacrene has five isomers. Natural occurrences The essential oils of lamium, deadnettles (genus ''Lamium''), Stachys, hedgenettles (genus ''Stachys''), and ''Clausena anisata'' are characterized by their high contents of germacrene D. Germacrene B is a major component of Patchouli#Essential_oil, patchouli oil. References Further reading General * Germacrene A * * * * * * Germacrene D * * * * * * * {{refend Alkene derivatives Sesquiterpenes Cycloalkenes Multiple Chemboxes, B ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Farnesyl Diphosphate
Farnesyl pyrophosphate (FPP), also known as farnesyl diphosphate (FDP), is the precursor to all sesquiterpenes, which comprises thousands of compounds. These include all sesquiterpenes as well as sterols and carotenoids. It is also used in the synthesis of CoQ (part of the electron transport chain), as well as dehydrodolichol diphosphate (a precursor of dolichol, which transports proteins to the ER lumen for ''N''-glycosylation). Biosynthesis Farnesyl pyrophosphate synthase (a prenyl transferase) catalyzes sequential condensation reactions of dimethylallyl pyrophosphate with 2 units of 3-isopentenyl pyrophosphate to form farnesyl pyrophosphate: : Pharmacology The above reactions are inhibited by bisphosphonates (used for osteoporosis). Farnesyl pyrophosphate is a selective agonist of TRPV3. Related compounds * Farnesene * Farnesol * Geranyl pyrophosphate *Geranylgeranyl pyrophosphate Geranylgeranyl pyrophosphate is an intermediate in the biosynthesis of diterpenes and d ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Parthenolide
Parthenolide is a sesquiterpene lactone of the germacranolide class which occurs naturally in the plant feverfew ('' Tanacetum parthenium''), after which it is named, and in the closely related tansy (''Tanacetum vulgare''). It is found in highest concentration in the flowers and fruit. Parthenolide's molecular structure depiction is often incorrect regarding the stereochemistry of the epoxide, although X-ray single crystal structures are available. Lack of solubility in water and bioavailability In pharmacology, bioavailability is a subcategory of absorption and is the fraction (%) of an administered drug that reaches the systemic circulation. By definition, when a medication is administered intravenously, its bioavailability is 100%. H ... limits the potential of parthenolide as a drug. References {{HDAC inhibitors Adiponectin receptor agonists Epoxides Histone deacetylase inhibitors Sesquiterpene lactones ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Biosynthesis
Biosynthesis, i.e., chemical synthesis occurring in biological contexts, is a term most often referring to multi-step, enzyme-Catalysis, catalyzed processes where chemical substances absorbed as nutrients (or previously converted through biosynthesis) serve as enzyme substrate (chemistry), substrates, with conversion by the living organism either into simpler or more complex Product (chemistry), products. Examples of biosynthetic pathways include those for the production of amino acids, lipid membrane components, and nucleotides, but also for the production of all classes of biological macromolecules, and of acetyl-coenzyme A, adenosine triphosphate, nicotinamide adenine dinucleotide and other key intermediate and transactional molecules needed for metabolism. Thus, in biosynthesis, any of an array of Chemical compound, compounds, from simple to complex, are converted into other compounds, and so it includes both the catabolism and anabolism (building up and breaking down) of comple ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Levorotatory
Optical rotation, also known as polarization rotation or circular birefringence, is the rotation of the orientation of the plane of polarization about the optical axis of linearly polarized light as it travels through certain materials. Circular birefringence and circular dichroism are the manifestations of optical activity. Optical activity occurs only in chiral materials, those lacking microscopic mirror symmetry. Unlike other sources of birefringence which alter a beam's state of polarization, optical activity can be observed in fluids. This can include gases or solutions of chiral molecules such as sugars, molecules with helical secondary structure such as some proteins, and also chiral liquid crystals. It can also be observed in chiral solids such as certain crystals with a rotation between adjacent crystal planes (such as quartz) or metamaterials. When looking at the source of light, the rotation of the plane of polarization may be either to the right (dextrorotatory o ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Ester
In chemistry, an ester is a compound derived from an acid (either organic or inorganic) in which the hydrogen atom (H) of at least one acidic hydroxyl group () of that acid is replaced by an organyl group (R). These compounds contain a distinctive functional group. Analogues derived from oxygen replaced by other chalcogens belong to the ester category as well. According to some authors, organyl derivatives of acidic hydrogen of other acids are esters as well (e.g. amides), but not according to the IUPAC. Glycerides are fatty acid esters of glycerol; they are important in biology, being one of the main classes of lipids and comprising the bulk of animal fats and vegetable oils. Lactones are cyclic carboxylic esters; naturally occurring lactones are mainly 5- and 6-membered ring lactones. Lactones contribute to the aroma of fruits, butter, cheese, vegetables like celery and other foods. Esters can be formed from oxoacids (e.g. esters of acetic acid, carbonic acid ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Ethyl Group
In organic chemistry, an ethyl group (abbr. Et) is an alkyl substituent with the formula , derived from ethane (). ''Ethyl'' is used in the International Union of Pure and Applied Chemistry The International Union of Pure and Applied Chemistry (IUPAC ) is an international federation of National Adhering Organizations working for the advancement of the chemical sciences, especially by developing nomenclature and terminology. It is ...'s nomenclature of organic chemistry for a saturated two-carbon moiety in a molecule, while the prefix "''eth-''" is used to indicate the presence of two carbon atoms in the molecule. Ethylation Ethylation is the formation of a compound by introduction of the ethyl group. The most widely practiced example of this reaction is the ethylation of benzene with ethylene to yield ethylbenzene, a precursor to styrene, which is a precursor to polystyrene. Approximately 24.7 million tons of ethylbenzene were produced in 1999. :: Many ethyl ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Toxic
Toxicity is the degree to which a chemical substance or a particular mixture of substances can damage an organism. Toxicity can refer to the effect on a whole organism, such as an animal, bacterium, or plant, as well as the effect on a substructure of the organism, such as a cell ( cytotoxicity) or an organ such as the liver ( hepatotoxicity). Sometimes the word is more or less synonymous with poisoning in everyday usage. A central concept of toxicology is that the effects of a toxicant are dose-dependent; even water can lead to water intoxication when taken in too high a dose, whereas for even a very toxic substance such as snake venom there is a dose below which there is no detectable toxic effect. Toxicity is species-specific, making cross-species analysis problematic. Newer paradigms and metrics are evolving to bypass animal testing, while maintaining the concept of toxicity endpoints. Etymology In Ancient Greek medical literature, the adjective ''τοξικόν'' ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
