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Hydroxyquinoline Synthesis
8-Hydroxyquinoline (also known as oxine) is an organic compound derived from the heterocycle quinoline. A colorless solid, its conjugate base is a chelating agent, which is used for the quantitative determination of metal ions. In aqueous solution 8-hydroxyquinoline has a pKa value of ca. 9.9 It reacts with metal ions, losing the proton and forming 8-hydroxyquinolinato-chelate complexes. The aluminium complex, is a common component of organic light-emitting diodes (OLEDs). Substituents on the quinoline ring affect the luminescence properties. In its photo-induced excited-state, 8-hydroxyquinoline converts to zwitterionic isomers, in which the hydrogen atom is transferred from oxygen to nitrogen. History 8-hydroxyquinoline was first obtained by Hugo Weidel and his student Albert Cobenzl in 1880. They decarboxylated so-called oxycinchoninic acid (from cinchonine) and characterized the resulting compound as melting at about 70°C. They identified that the hydroxy group is on ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Organic Compound
Some chemical authorities define an organic compound as a chemical compound that contains a carbon–hydrogen or carbon–carbon bond; others consider an organic compound to be any chemical compound that contains carbon. For example, carbon-containing compounds such as alkanes (e.g. methane ) and its derivatives are universally considered organic, but many others are sometimes considered inorganic, such as certain compounds of carbon with nitrogen and oxygen (e.g. cyanide ion , hydrogen cyanide , chloroformic acid , carbon dioxide , and carbonate ion ). Due to carbon's ability to catenate (form chains with other carbon atoms), millions of organic compounds are known. The study of the properties, reactions, and syntheses of organic compounds comprise the discipline known as organic chemistry. For historical reasons, a few classes of carbon-containing compounds (e.g., carbonate salts and cyanide salts), along with a few other exceptions (e.g., carbon dioxide, and even ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Antiseptic
An antiseptic ( and ) is an antimicrobial substance or compound that is applied to living tissue to reduce the possibility of sepsis, infection, or putrefaction. Antiseptics are generally distinguished from ''antibiotics'' by the latter's ability to safely destroy bacteria within the body, and from ''disinfectants'', which destroy microorganisms found on non-living objects. Antibacterials include antiseptics that have the proven ability to act against bacteria. Microbicides which destroy virus particles are called viricides or antivirals. Antifungals, also known as antimycotics, are pharmaceutical fungicides used to treat and prevent mycosis (fungal infection). Surgery Antiseptic practices evolved in the 19th century through multiple individuals. Ignaz Semmelweis showed already in 1847-1848 that hand washing prior to delivery reduced puerperal fever. Despite this, many hospitals continued to practice surgery in unsanitary conditions, with some surgeons taking pride in t ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Trace Metal Detection Test
The trace metal detection test or technique was developed during the Vietnam War in the 1960s to identify individuals who may have been carrying firearms against their skin. A 0.2% solution of 8-hydroxyquinoline in isopropanol is sprayed on the skin. After several minutes, the skin is illuminated with shortwave ultraviolet (UV) light, revealing a pattern and type of metal based on trace amounts of metal transferred to the skin, which are invisible under normal lighting. The technique was later adopted by police in the United States to help determine if a person had carried a firearm. In a California crime, an automatic handgun carried in the waistband of a criminal reportedly produced an impression of the weapon's serial number. The presence and persistence of a detectable residue depend primarily on the amount of perspiration, length of contact, and time since exposure. A few minutes of exposure can leave detectable residue, and the result can remain for up to forty-eight hours. Pre ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Ionophore
In chemistry, an ionophore () is a chemical species that reversibly binds ions. Many ionophores are lipid-soluble entities that transport ions across the cell membrane. Ionophores catalyze ion transport across hydrophobic membranes, such as liquid polymeric membranes (carrier-based ion selective electrodes) or lipid bilayers found in the living cells or synthetic vesicles ( liposomes). Structurally, an ionophore contains a hydrophilic center and a hydrophobic portion that interacts with the membrane. Some ionophores are synthesized by microorganisms to import ions into their cells. Synthetic ion carriers have also been prepared. Ionophores selective for cations and anions have found many applications in analysis. These compounds have also shown to have various biological effects and a synergistic effect when combined with the ion they bind. Classification Biological activities of metal ion-binding compounds can be changed in response to the increment of the metal concentr ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
QUPIC
PB-22 (QUPIC, SGT-21 or 1-pentyl-1''H''-indole-3-carboxylic acid 8-quinolinyl ester) is a designer drug offered by online vendors as a cannabimimetic agent, and detected being sold in synthetic cannabis products in Japan in 2013. PB-22 represents a structurally unique synthetic cannabinoid chemotype, since it contains an ester linker at the indole 3-position, rather than the precedented ketone of JWH-018 and its analogs, or the amide of APICA and its analogs. PB-22 has an EC50 of 5.1 nM for human CB1 receptors, and 37 nM for human CB2 receptors. PB-22 produces bradycardia and hypothermia in rats at doses of 0.3–3 mg/kg, suggesting potent cannabinoid-like activity. The magnitude and duration of hypothermia induced in rats by PB-22 was notably greater than JWH-018, AM-2201, UR-144, XLR-11, APICA, or STS-135, with a reduction of body temperature still observable six hours after dosing. One clinical toxicology study found PB-22 to be the cause of seizures in a ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
PBT2
PBT2 is a safe-for-human-use Zinc ionophore and an experimental drug candidate. It is a second-generation 8-hydroxyquinoline analog intended to be a successor to clioquinol and a potential treatment of Alzheimer's disease and Huntington's disease. Clinical trials PBT2 was the subject of three phase II clinical trials for Alzheimer's disease ("EURO", "IMAGINE" and "IMAGINE EXTENSION") and one for Huntington's disease ("REACH2HD"). The cognition efficacy results for Alzheimer's disease were mixed. The EURO trial showed some improvements in cognitive functions, in particular executive function domains, while the IMAGINE study did not."Prana Biotech Plunges 76%; Drug Fails in Alzheimer Study""PBT2 Takes a Dive in Phase 2 Alzheimer's Trial" Although there is no evidence that PBT2 is of any benefit in Alzheimer's dementia,''"There is no evidence that MPACs (PBT1 or PBT2) are of benefit in Alzheimer's dementia"'' the number of subjects treated with PBT2 for AD in Phase II placebo ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Nitroxoline
Nitroxoline is an antibiotic that has been in use in Europe for about fifty years, and has proven to be very effective at combating biofilm infections. Nitroxoline was shown to cause a decrease in the biofilm density of ''P. aeruginosa'' infections, which would allow access to the infection by the immune system ''in vivo''. It was shown that nitroxoline functions by chelating Fe2+ and Zn2+ ions from the biofilm matrix; when Fe2+ and Zn2+ were reintroduced into the system, biofilm formation activity was restored. The biofilm degradation ability is comparable to EDTA derivatives, but this drug has a history of human use in clinical settings and therefore has a precedent with which to allow its use against “slimy” biofilm infections. Anticancer activity The chelating activities of nitroxoline have also been used in an anticancer setting. Nitroxoline has been shown to be more cytotoxic to HL60, DHL-4, PANC-1, and cells lines than clioquinol and other 8-hydroxyquinoline derivat ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Co-evolution
In biology, coevolution occurs when two or more species reciprocally affect each other's evolution through the process of natural selection. The term sometimes is used for two traits in the same species affecting each other's evolution, as well as gene-culture coevolution. Charles Darwin mentioned evolutionary interactions between flowering plants and insects in ''On the Origin of Species'' (1859). Although he did not use the word coevolution, he suggested how plants and insects could evolve through reciprocal evolutionary changes. Naturalists in the late 1800s studied other examples of how interactions among species could result in reciprocal evolutionary change. Beginning in the 1940s, plant pathologists developed breeding programs that were examples of human-induced coevolution. Development of new crop plant varieties that were resistant to some diseases favored rapid evolution in pathogen populations to overcome those plant defenses. That, in turn, required the development of ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Diffuse Knapweed
''Centaurea diffusa'', also known as diffuse knapweed, white knapweed or tumble knapweed, is a member of the genus ''Centaurea'' in the family Asteraceae. This species is common throughout western North America but is not actually native to the North American continent, but to the eastern Mediterranean. Description Diffuse knapweed is an annual or biennial plant, generally growing to between 10 and 60 cm in height. It has a highly branched stem and a large taproot, as well as a basal rosette of leaves with smaller leaves alternating on the upright stems. Flowers are usually white or pink and grow out of urn-shaped heads carried at the tips of the many branches. Diffuse knapweed often assumes a short rosette form for one year, reaching maximum size, then rapidly growing and flowering during the second year. A single plant can produce approximately 18,000 seeds. Synonyms * ''Centaurea microcalathina'' Tarassov * ''Centaurea cycladum'' Heldr. * ''Centaurea parviflora'' Si ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
8-Mercaptoquinoline
8-Mercaptoquinoline is the organosulfur compound with the formula C9H7NSH. It is a derivative of the heterocycle quinoline, substituted in the 8-position with a thiol group. The compound is an analog of 8-hydroxyquinoline, a common chelating agent. The compound is a colorless solid. Preparation Quinoline reacts with chlorosulfuric acid to form quinoline-8-sulfonyl chloride, which reacts with triphenylphosphine in toluene Toluene (), also known as toluol (), is a substituted aromatic hydrocarbon with the chemical formula , often abbreviated as , where Ph stands for the phenyl group. It is a colorless, water Water is an inorganic compound with the c ... to form 8-mercaptoquinoline. :: References {{DEFAULTSORT:Mercaptoquinoline, 8- Thiols Quinolines ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Liquid Bandage
Liquid bandage is a topical skin treatment for minor wounds which binds to the skin to form a protective polymeric layer that keeps dirt and germs out and moisture in.Petkewich, R. "Liquid Bandages" (2008) ''Chemical & Engineering News.'' vol. 86(24) p. 61. It can be directly applied to the wound after removing debris. For the fast-acting, reactive adhesive that is used to mend deep cuts or surgery wounds, see cyanoacrylates (specifically 2-Octyl cyanoacrylate). Design Liquid bandage is typically a polymer dissolved in a solvent (commonly water or an alcohol), sometimes with an added antiseptic and local anesthetic, although the alcohol in some brands may serve the same purpose. These products protect the wound by forming a thin film of polymer when the carrier evaporates. Polymers used may include polyvinylpyrrolidone (water based), ethyl cellulose, pyroxylin/nitrocellulose or poly(methylacrylate-isobutene-monoisopropylmaleate) (alcohol based), and acrylate or siloxane ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Transcription Inhibitor
Transcription is the process of copying a segment of DNA into RNA for the purpose of gene expression. Some segments of DNA are transcribed into RNA molecules that can encode proteins, called messenger RNA (mRNA). Other segments of DNA are transcribed into RNA molecules called non-coding RNAs (ncRNAs). Both DNA and RNA are nucleic acids, which use base pairs of nucleotides as a complementary language. During transcription, a DNA sequence is read by an RNA polymerase, which produces a complementary, antiparallel RNA strand called a primary transcript. In virology, the term transcription is used when referring to mRNA synthesis from a viral RNA molecule. The genome of many RNA viruses is composed of negative-sense RNA which acts as a template for positive sense viral messenger RNA - a necessary step in the synthesis of viral proteins needed for viral replication. This process is catalyzed by a viral RNA dependent RNA polymerase. Background A DNA transcription unit encoding f ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
