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Oleandrose
Oleandrose is a type of carbohydrate with the chemical formula C7H14O4. With a six-carbon chain, it is classified as a hexose. With two hydroxyl groups replaced with hydrogen atoms, it is a dideoxy sugar. The hydroxyl group at C3 is methylated. Occurrence Oleandrdose is found in the leaves of ''Nerium oleander'' and may contribute to the toxicity of the plant. Oleandrose is also a component of several naturally-occurring chemical compounds including the avermectins ( emamectin, abamectins, ivermectin, and others), the macrolide antibiotic oleandomycin, and the cardiac glycoside oleandrin Oleandrin is a cardiac glycoside found in the poisonous plant oleander (''Nerium oleander'' L.). As a main phytochemical of oleander, oleandrin is associated with the toxicity of oleander sap, and has similar properties to digoxin. Oleander has .... Laboratory syntheses of L-oleandrose and DL-oleandrose have been reported. See also * Sarmentose, a diastereomeric dideoxy sugar Referen ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Oleandrin
Oleandrin is a cardiac glycoside found in the poisonous plant oleander (''Nerium oleander'' L.). As a main phytochemical of oleander, oleandrin is associated with the toxicity of oleander sap, and has similar properties to digoxin. Oleander has been used in traditional medicine for its presumed therapeutic purposes, such as for treating cardiac insufficiency. There is no clinical evidence that oleander or its constituents, including oleandrin, are safe or effective. Oleandrin is not approved by regulatory agencies as a prescription drug or dietary supplement. Structure and reactivity The structure of oleandrin contains a central steroid nucleus with an unsaturated lactone ring structure on C17 and a dideoxy arabinose group on C3. In addition, the steroid ring has a substitute of an acetyloxy group on C16. The sugar forming the glycoside is L-oleandrose. Oleandrin resembles very much other glycosides like ouabain and digoxin but has less effect than digoxin. It is however ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Emamectin
Emamectin is the 4-deoxy-4-methylamino derivative of abamectin, a 16-membered macrocyclic lactone produced by the fermentation of the soil actinomycete ''Streptomyces avermitilis''. It is generally prepared as the salt (chemistry), salt with benzoic acid, emamectin benzoate, which is a white or faintly yellow powder. Emamectin is widely used in the US and Canada as an insecticide because of its chloride channel activation properties. History Emamectin, produced by the bacterium ''Streptomyces avermitilis'', belongs to the avermectin family of compounds all of which exhibit toxicity for nematodes, arthropods, and several other pests. The benzoate salt of emamectin in particular has found widespread use as an insecticide and is approved by the EPA for use in prevention of emerald ash borer in ash trees. Emamectin is derived from avermectin B1, also known as abamectin, a mixture of the natural avermectin B1a and B1b. Emamectin has also shown promising applications in the eradicatio ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Avermectin
The avermectins are a group of 16-membered Macrolide, macrocyclic lactone derivatives with potent anthelmintic and Insecticide, insecticidal properties. These naturally occurring compounds are generated as fermentation products by ''Streptomyces avermitilis'', a soil actinomycete. Eight different avermectins were isolated in four pairs of homologue compounds (A1, A2, B1, B2), with a major (a-component) and minor (b-component) component usually in ratios of 80:20 to 90:10. Avermectin B1, a mixture of B1a and B1b, is the drug and pesticide abamectin. Other anthelmintics derived from the avermectins include ivermectin, selamectin, doramectin, eprinomectin. Half of the 2015 Nobel Prize in Physiology or Medicine was awarded to William C. Campbell (scientist), William C. Campbell and Satoshi Ōmura for discovering avermectin, "the derivatives of which have radically lowered the incidence of Onchocerciasis, river blindness and lymphatic filariasis, as well as showing efficacy against an ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Oleandomycin
Oleandomycin is a macrolide antibiotic. It is synthesized from strains of ''Streptomyces antibioticus''. It is weaker than erythromycin. It used to be sold under the brand name Sigmamycine, combined with tetracycline, and made by the company Rosa-Phytopharma in France. Medical uses Oleandomycin inhibits the bacteria responsible for upper respiratory tract infections. Its spectrum of activity includes bacteria in the ''Staphylococcus'' and ''Enterococcus'' genera. The MIC for oleandomycin is 0.3-3 μg/mL for ''Staphylococcus aureus''. Oleandomycin is approved as a veterinary antibiotic in some countries. It has been approved as a swine and poultry antibiotic in the United States. However, it is currently only approved in the United States for production uses. Pharmacology Mechanism of action Oleandomycin is a bacteriostatic agent. Like erythromycin, oleandomycin binds to the 50s subunit of bacterial ribosomes, inhibiting the completion of proteins vital to survival ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Carbohydrate
A carbohydrate () is a biomolecule composed of carbon (C), hydrogen (H), and oxygen (O) atoms. The typical hydrogen-to-oxygen atomic ratio is 2:1, analogous to that of water, and is represented by the empirical formula (where ''m'' and ''n'' may differ). This formula does not imply direct covalent bonding between hydrogen and oxygen atoms; for example, in , hydrogen is covalently bonded to carbon, not oxygen. While the 2:1 hydrogen-to-oxygen ratio is characteristic of many carbohydrates, exceptions exist. For instance, uronic acids and deoxy-sugars like fucose deviate from this precise stoichiometric definition. Conversely, some compounds conforming to this definition, such as formaldehyde and acetic acid, are not classified as carbohydrates. The term is predominantly used in biochemistry, functioning as a synonym for saccharide (), a group that includes sugars, starch, and cellulose. The saccharides are divided into four chemical groups: monosaccharides, disaccharides, ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Hexose
In chemistry, a hexose is a monosaccharide (simple sugar) with six carbon atoms. The chemical formula for all hexoses is , and their molecular weight is 180.156 g/mol. Hexoses exist in two forms, open-chain or cyclic, that easily convert into each other in aqueous solutions. The open-chain form of a hexose, which usually is favored in solutions, has the general structure , where ''n'' is 1, 2, 3, 4, 5. Namely, five of the carbons have one hydroxyl functional group () each, connected by a single bond, and one has an oxo group (), forming a carbonyl group (). The remaining bonds of the carbon atoms are satisfied by seven hydrogen atoms. The carbons are commonly numbered 1 to 6 starting at the end closest to the carbonyl. Hexoses are extremely important in biochemistry, both as isolated molecules (such as glucose and fructose) and as building blocks of other compounds such as starch, cellulose, and glycosides. Hexoses can form dihexose (like sucrose) by a condensation re ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Dideoxy Sugar
Dideoxynucleotides are chain-elongating inhibitors of DNA polymerase, used in the Sanger method for DNA sequencing. They are also known as 2',3' because both the 2' and 3' positions on the ribose lack hydroxyl groups, and are abbreviated as ''ddNTPs'' (ddGTP, ddATP, ddTTP and ddCTP). Role in the Sanger method The Sanger method is used to amplify a target segment of DNA, so that the DNA sequence can be determined precisely. The incorporation of ddNTPs in the reaction valves are simply used to terminate the synthesis of a growing DNA strand, resulting in partially replicated DNA fragments. This is because DNA polymerase requires the 3' OH group of the growing chain and the 5' phosphate group of the incoming dNTP to create a phosphodiester bond. Sometimes the DNA polymerase will incorporate a ddNTP and the absence of the 3' OH group will interrupt the condensation reaction between the 5' phosphate (following the cleavage of pyrophosphate) of the incoming nucleotide with the 3' ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Methyl
In organic chemistry, a methyl group is an alkyl derived from methane, containing one carbon atom bonded to three hydrogen atoms, having chemical formula (whereas normal methane has the formula ). In formulas, the group is often abbreviated as Me. This hydrocarbon group occurs in many organic compounds. It is a very stable group in most molecules. While the methyl group is usually part of a larger molecule, bonded to the rest of the molecule by a single covalent bond (), it can be found on its own in any of three forms: methanide anion (), methylium cation () or methyl radical (). The anion has eight valence electrons, the radical seven and the cation six. All three forms are highly reactive and rarely observed. Methyl cation, anion, and radical Methyl cation The methylium cation () exists in the gas phase, but is otherwise not encountered. Some compounds are considered to be sources of the cation, and this simplification is used pervasively in organic chemistry. For exam ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Nerium Oleander
''Nerium oleander'' ( ), commonly known as oleander or rosebay, is a shrub or small tree cultivated worldwide in temperate and subtropical areas as an ornamental and landscaping plant. It is the Monotypic taxon, only species currently classified in the genus ''Nerium'', belonging to subfamily Apocynoideae of the dogbane family Apocynaceae. It is so widely cultivated that no precise region of origin has been identified, though it is usually associated with the Mediterranean Basin. Nerium grows to tall. It is most commonly grown in its natural shrub form, but can be trained into a small tree with a single trunk. It is tolerant to both drought and inundation, but not to prolonged frost. White, pink or red five-lobed flowers grow in clusters year-round, peaking during the summer. The fruit is a long narrow pair of follicles, which splits open at maturity to release numerous downy seeds. Nerium is a poisonous plant but its bitterness renders it unpalatable to humans and most anima ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Abamectin
Abamectin (also called avermectin B1) is a widely used insecticide and anthelmintic. Abamectin, is a member of the avermectin family and is a natural fermentation product of soil dwelling actinomycete '' Streptomyces avermitilis''. Abamectin differs from ivermectin, the popular member of the avermectin family, by a double bond between carbons 22 and 23. Fermentation of '' Streptomyces avermitilis'' yields eight closely related avermectin homologs, with the B1a and B1b forms comprising the majority of the fermentation. The non-proprietary name, abamectin, refers to a mixture of B1a (~80%) and B1b (~20%). Out of all the avermectins, abamectin is the only one that is used both in agriculture and pharmaceuticals. Mode of action Avermectins bind to the glutamate-gated chloride channels that are found in invertebrate nerve and muscle cells. They cause hyperpolarization of these cells resulting in paralysis and death. Mammals only possess glutamate-gated chloride channels in the brain ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Ivermectin
Ivermectin is an antiparasitic drug. After its discovery in 1975, its first uses were in veterinary medicine to prevent and treat heartworm and acariasis. Approved for human use in 1987, it is used to treat infestations including head lice, scabies, river blindness (onchocerciasis), strongyloidiasis, trichuriasis, ascariasis and lymphatic filariasis. It works through many mechanisms to kill the targeted parasites, and can be taken by mouth, or applied to the skin for external infestations. It belongs to the avermectin family of medications. William Campbell and Satoshi Ōmura were awarded the 2015 Nobel Prize in Physiology or Medicine for its discovery and applications. It is on the World Health Organization's List of Essential Medicines, and is approved by the US Food and Drug Administration (FDA) as an antiparasitic agent. In 2022, it was the 314th most commonly prescribed medication in the United States, with more than 200,000 prescriptions. It is available as ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Cardiac Glycoside
Cardiac glycosides are a class of organic compounds that increase the output force of the heart and decrease its rate of contractions by inhibiting the cellular sodium-potassium ATPase pump. Their beneficial medical uses include treatments for congestive heart failure and cardiac arrhythmias; however, their relative toxicity prevents them from being widely used. Most commonly found as defensive poisons in several plant genera such as ''Digitalis'' (the foxgloves) and '' Asclepias'' (the milkweeds), these compounds nevertheless have a diverse range of biochemical effects regarding cardiac cell function and have also been suggested for use in cancer treatment. Classification General structure The general structure of a cardiac glycoside consists of a steroid molecule attached to a sugar (glycoside) and an R group. The steroid nucleus consists of four fused rings to which other functional groups such as methyl, hydroxyl, and aldehyde groups can be attached to influence th ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
