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1,8-Naphthyridine
1,8-Naphthyridine is an organic compound with the formula C8H6N2. It is the most well-studied of the six isomeric naphthyridines, a subset of diazanaphthalenes with nitrogen in the separate rings. Enoxacin, nalidixic acid, and trovafloxacin are 1,8-naphthyridine derivatives with antibacterial properties related to the fluoroquinolones. Coordination chemistry With flanking nitrogen centers, 1,8-naphthyridine serves as a binucleating ligand in coordination chemistry A coordination complex consists of a central atom or ion, which is usually metallic and is called the ''coordination centre'', and a surrounding array of bound molecules or ions, that are in turn known as ''ligands'' or complexing agents. Many .... References {{DEFAULTSORT:Naphthyridine, 1,8- Naphthyridines ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Nalidixic Acid
Nalidixic acid (tradenames Nevigramon, NegGram, Wintomylon and WIN 18,320) is the first of the synthetic quinolone antibiotics. In a technical sense, it is a naphthyridone, not a quinolone: its ring structure is a 1,8-naphthyridine nucleus that contains two nitrogen atoms, unlike quinoline, which has a single nitrogen atom. Synthetic quinolone antibiotics were discovered by George Lesher and coworkers as a byproduct of chloroquine manufacture in the 1960s; nalidixic acid itself was used clinically, starting in 1967. Nalidixic acid is effective primarily against Gram-negative bacteria, with minor anti-Gram-positive activity. In lower concentrations, it acts in a bacteriostatic manner; that is, it inhibits growth and reproduction. In higher concentrations, it is bactericidal, meaning that it kills bacteria instead of merely inhibiting their growth. It has historically been used for treating urinary tract infections, caused, for example, by ''Escherichia coli'', ''Proteus'', ''Sh ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Diazanaphthalene
Diazanaphthalenes are a class of aromatic heterocyclic chemical compounds that have the formula C8H6N2. They consist of a naphthalene double ring in which two of the carbon atoms have been replaced with nitrogen atoms. There are ten positional isomers, which differ by the locations of the nitrogen atoms. The group consist of two subgroups: *four ''benzodiazines'' with both N atoms in one ring: cinnoline, quinazoline, quinoxaline, and phthalazine Phthalazine, also called benzo-orthodiazine or benzopyridazine, is a heterocyclic organic compound with the molecular formula C8H6N2. It is isomeric with other naphthyridines including quinoxaline, cinnoline and quinazoline. Synthesis Phthalazi ... *six ''naphthyridines'' with one N atom in each ring Isomers References {{reflist ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
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 a member of the International Science Council (ISC). IUPAC is registered in Zürich, Switzerland, and the administrative office, known as the "IUPAC Secretariat", is in Research Triangle Park, North Carolina, United States. This administrative office is headed by IUPAC's executive director, currently Lynn Soby. IUPAC was established in 1919 as the successor of the International Congress of Applied Chemistry for the advancement of chemistry. Its members, the National Adhering Organizations, can be national chemistry societies, national academies of sciences, or other bodies representing chemists. There are fifty-four National Adhering Organizations and three Associate National Adhering Organizations. IUPAC's Inter-divisional Committee on ... [...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] |
Enoxacin
EnoxacinEnoxacin is sold under the following trade names: Almitil, Bactidan, Bactidron, Comprecin, Enoksetin, Enoxen, Enroxil, Enoxin, Enoxor, Flumark, Penetrex, Gyramid, Vinone. is an oral broad-spectrum fluoroquinolone antibacterial agent used in the treatment of urinary tract infections and gonorrhea. Insomnia is a common adverse effect. It is no longer available in the United States. It has been shown recently that it may have cancer inhibiting effect. Mechanism of action Quinolones and fluoroquinolones are bactericidal drugs, eradicating bacteria by interfering with DNA replication. Like other fluoroquinolones, enoxacin functions by inhibiting bacterial DNA gyrase and topoisomerase IV. The inhibition of these enzymes prevents bacterial DNA replication, transcription, repair and recombination. Recently, it was shown that Enoxacin inhibits the expression of the microRNA mir-34-5p, leading to an increase in the lifespan of the nematode C. elegans. Enoxacin is active against man ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Trovafloxacin
Trovafloxacin (sold as Trovan by Pfizer and Turvel by Laboratorios Almirall) is a broad spectrum antibiotic that inhibits the uncoiling of supercoiled DNA in various bacteria by blocking the activity of DNA gyrase and topoisomerase IV. It was withdrawn from the market due to the risk of hepatotoxicity. It had better Gram-positive bacterial coverage but less Gram-negative coverage than the previous fluoroquinolones. Adverse reactions Trovafloxacin use is significantly restricted due to its high potential for inducing serious and sometimes fatal liver damage. Currently, the drug is not approved for use in the U.S. or the European Union due to association with cases of acute liver failure and death. Manufacturing The key reaction in building the ring consists of 1,3-Dipolar cycloaddition of ethyl diazoacetate to N-Cbz- 3-pyrroline to afford the pyrrazolidine (3). Pyrolysis results in loss of nitrogen and formation of the cyclopropylpyrrolidine ring. The stereochemistry of the r ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Fluoroquinolone
A quinolone antibiotic is a member of a large group of broad-spectrum bacteriocidals that share a bicyclic core structure related to the substance 4-quinolone. They are used in human and veterinary medicine to treat bacterial infections, as well as in animal husbandry, specifically poultry production. Nearly all quinolone antibiotics in use are fluoroquinolones, which contain a fluorine atom in their chemical structure and are effective against both Gram-negative and Gram-positive bacteria. One example is ciprofloxacin, one of the most widely used antibiotics worldwide. Medical uses Fluoroquinolones are often used for genitourinary infections and are widely used in the treatment of hospital-acquired infections associated with urinary catheters. In community-acquired infections, they are recommended only when risk factors for multidrug resistance are present or after other antibiotic regimens have failed. However, for serious acute cases of pyelonephritis or bacterial pros ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Ligand
In coordination chemistry, a ligand is an ion or molecule (functional group) that binds to a central metal atom to form a coordination complex. The bonding with the metal generally involves formal donation of one or more of the ligand's electron pairs, often through Lewis bases. The nature of metal–ligand bonding can range from covalent to ionic. Furthermore, the metal–ligand bond order can range from one to three. Ligands are viewed as Lewis bases, although rare cases are known to involve Lewis acidic "ligands". Metals and metalloids are bound to ligands in almost all circumstances, although gaseous "naked" metal ions can be generated in a high vacuum. Ligands in a complex dictate the reactivity of the central atom, including ligand substitution rates, the reactivity of the ligands themselves, and redox. Ligand selection requires critical consideration in many practical areas, including bioinorganic and medicinal chemistry, homogeneous catalysis, and environmental chemi ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Coordination Chemistry
A coordination complex consists of a central atom or ion, which is usually metallic and is called the ''coordination centre'', and a surrounding array of bound molecules or ions, that are in turn known as ''ligands'' or complexing agents. Many metal-containing compounds, especially those that include transition metals (elements like titanium that belong to the Periodic Table's d-block), are coordination complexes. Nomenclature and terminology Coordination complexes are so pervasive that their structures and reactions are described in many ways, sometimes confusingly. The atom within a ligand that is bonded to the central metal atom or ion is called the donor atom. In a typical complex, a metal ion is bonded to several donor atoms, which can be the same or different. A polydentate (multiple bonded) ligand is a molecule or ion that bonds to the central atom through several of the ligand's atoms; ligands with 2, 3, 4 or even 6 bonds to the central atom are common. These compl ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
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