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Ansamycin
Ansamycins is a family of bacterial secondary metabolites that show antimicrobial activity against many Gram-positive and some Gram-negative bacteria, and includes various compounds, including streptovaricins and rifamycins. In addition, these compounds demonstrate antiviral activity towards bacteriophages and poxviruses. They are somewhat similar in structure to macrolide antibiotics, but because they have a lactam instead of a lactone, they do not belong in the class of macrolides. __TOC__ Structure They are named ansamycins (from the Latin ansa, ''handle'') because of their unique structure, which consists of an aromatic moiety bridged by an aliphatic chain. The main difference between various derivatives of ansamycins is the aromatic moiety, which can be a naphthalene ring or a naphthoquinone ring as in rifamycin and the naphthomycins. Another variation consists of benzene or a benzoquinone ring system as in geldanamycin or ansamitocin. Ansamycins were first discovere ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Naphthomycin
Naphthomycins are a group of closely related antimicrobial chemical compounds isolated from ''Streptomyces''. They are considered a subclass of ansamycin Ansamycins is a family of bacterial secondary metabolites that show antimicrobial activity against many Gram-positive and some Gram-negative bacteria, and includes various compounds, including streptovaricins and rifamycins. In addition, these ...s. Members include: * Naphthomycin A * Naphthomycin B * Naphthomycin C * Naphthomycin D * Naphthomycin E * Naphthomycin F * Naphthomycin G * Naphthomycin H * Naphthomycin I * Naphthomycin J * Naphthomycin K * Naphthomycin L * Naphthomycin M * Naphthomycin N Chemical structures File:Naphthomycin A.svg, Naphthomycin A File:Naphthomycin B.svg, Naphthomycin B File:Naphthomycin C.svg, Naphthomycin C File:Naphthomycin D.svg, Naphthomycin D File:Naphthomycin E.svg, Naphthomycin E File:Naphthomycin F.svg, Naphthomycin F File:Naphthomycin G.svg, Naphthomycin G References {{reflist An ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Macrolide
Macrolides are a class of mostly natural products with a large macrocyclic lactone ring to which one or more deoxy sugars, usually cladinose and desosamine, may be attached. Macrolides belong to the polyketide class of natural products. Some macrolides have antibiotic or antifungal activity and are used as pharmaceutical drugs. Rapamycin is also a macrolide and was originally developed as an antifungal, but has since been used as an immunosuppressant drug and is being investigated as a potential longevity therapeutic. Macrolides are a diverse group with many members of very different properties: * Macrolides with 14-, 15-, or 16-membered rings and two attached sugar molecules are antibiotics that bind to bacterial ribosomes, the key representative being erythromycin. The term "macrolide antibiotics" tend to refer to just this class. * Some macrolides with very large (20+ membered) rings are immunosuppresants, the prototypical one being rapamycin. * Some 23-membered ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Rifamycin
The rifamycins are a group of antibiotics that are synthesized either naturally by the bacterium '' Amycolatopsis rifamycinica'' or artificially. They are a subclass of the larger family of ansamycins. Rifamycins are particularly effective against mycobacteria, and are therefore used to treat tuberculosis, leprosy, and mycobacterium avium complex (MAC) infections. The rifamycin group includes the classic rifamycin drugs as well as the rifamycin derivatives rifampicin (or rifampin), rifabutin, rifapentine, rifalazil and rifaximin. Rifamycin, sold under the trade name Aemcolo, is approved in the United States for treatment of travelers' diarrhea in some circumstances. The name "rifamycin" (originally "rifomycin") was derived from the 1955 French film ''Rififi''. Bacterium ''Streptomyces mediterranei'' was first isolated in 1957 from a soil sample collected near the beach-side town of St Raphael in southern France. The name was originally given by two microbiologists wor ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Geldanamycin
Geldanamycin is a 1,4-benzoquinone ansamycin Antitumor agent, antitumor antibiotic that inhibits the function of Hsp90 (Heat Shock Protein 90) by binding to the unusual ADP/ATP-binding pocket of the protein. HSP90 client proteins play important roles in the regulation of the cell cycle, cell growth, cell survival, apoptosis, angiogenesis and oncogenesis. Geldanamycin induces the degradation of proteins that are mutated or overexpressed in tumor cells such as v-Src, Bcr-Abl, p53, and ERBB2. This effect is mediated via HSP90. Despite its potent antitumor potential, geldanamycin presents several major drawbacks as a drug candidate such as hepatotoxicity, further, Jilani ''et al.''. reported that geldanamycin induces the apoptosis of erythrocytes under physiological concentrations. These side effects have led to the development of geldanamycin analogues, in particular analogues containing a derivatisation at the 17 position: * 17-AAG * 17-DMAG Biosynthesis Geldanamycin was original ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Rifamycins
The rifamycins are a group of antibiotics that are synthesized either naturally by the bacterium ''Amycolatopsis rifamycinica'' or artificially. They are a subclass of the larger family of ansamycins. Rifamycins are particularly effective against mycobacteria, and are therefore used to treat tuberculosis, leprosy, and mycobacterium avium complex (MAC) infections. The rifamycin group includes the classic rifamycin drugs as well as the rifamycin derivatives rifampicin (or rifampin), rifabutin, rifapentine, rifalazil and rifaximin. Rifamycin, sold under the trade name Aemcolo, is approved in the United States for treatment of travelers' diarrhea in some circumstances. The name "rifamycin" (originally "rifomycin") was derived from the 1955 French film ''Rififi''. Bacterium ''Streptomyces mediterranei'' was first isolated in 1957 from a soil sample collected near the beach-side town of St Raphael in southern France. The name was originally given by two microbiologists working ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Geldanamycin
Geldanamycin is a 1,4-benzoquinone ansamycin Antitumor agent, antitumor antibiotic that inhibits the function of Hsp90 (Heat Shock Protein 90) by binding to the unusual ADP/ATP-binding pocket of the protein. HSP90 client proteins play important roles in the regulation of the cell cycle, cell growth, cell survival, apoptosis, angiogenesis and oncogenesis. Geldanamycin induces the degradation of proteins that are mutated or overexpressed in tumor cells such as v-Src, Bcr-Abl, p53, and ERBB2. This effect is mediated via HSP90. Despite its potent antitumor potential, geldanamycin presents several major drawbacks as a drug candidate such as hepatotoxicity, further, Jilani ''et al.''. reported that geldanamycin induces the apoptosis of erythrocytes under physiological concentrations. These side effects have led to the development of geldanamycin analogues, in particular analogues containing a derivatisation at the 17 position: * 17-AAG * 17-DMAG Biosynthesis Geldanamycin was original ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Streptovaricins
Streptovaricins are a group of structurally related macrolide antibiotics. They belong to the larger class of antibiotics known as ansamycins. References Macrolide antibiotics Ansamycins {{antibiotic-stub ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Tuberculosis
Tuberculosis (TB), also known colloquially as the "white death", or historically as consumption, is a contagious disease usually caused by ''Mycobacterium tuberculosis'' (MTB) bacteria. Tuberculosis generally affects the lungs, but it can also affect other parts of the body. Most infections show no symptoms, in which case it is known as inactive or latent tuberculosis. A small proportion of latent infections progress to active disease that, if left untreated, can be fatal. Typical symptoms of active TB are chronic cough with hemoptysis, blood-containing sputum, mucus, fever, night sweats, and weight loss. Infection of other organs can cause a wide range of symptoms. Tuberculosis is Human-to-human transmission, spread from one person to the next Airborne disease, through the air when people who have active TB in their lungs cough, spit, speak, or sneeze. People with latent TB do not spread the disease. A latent infection is more likely to become active in those with weakened I ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Ethers
In organic chemistry, ethers are a class of compounds that contain an ether group, a single oxygen atom bonded to two separate carbon atoms, each part of an organyl group (e.g., alkyl or aryl). They have the general formula , where R and R′ represent the organyl groups. Ethers can again be classified into two varieties: if the organyl groups are the same on both sides of the oxygen atom, then it is a simple or symmetrical ether, whereas if they are different, the ethers are called mixed or unsymmetrical ethers. A typical example of the first group is the solvent and anaesthetic diethyl ether, commonly referred to simply as "ether" (). Ethers are common in organic chemistry and even more prevalent in biochemistry, as they are common linkages in carbohydrates and lignin. Structure and bonding Ethers feature bent linkages. In dimethyl ether, the bond angle is 111° and C–O distances are 141 pm. The barrier to rotation about the C–O bonds is low. The bonding of oxygen ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Lactams
A lactam is a cyclic amide, formally derived from an amino alkanoic acid through cyclization reactions. The term is a portmanteau of the words '' lactone'' + ''amide''. Nomenclature Greek prefixes in alphabetical order indicate ring size. This ring-size nomenclature stems from the fact that hydrolysis of an α-lactam gives an α-amino acid and that of a β-Lactam gives a β-amino acid, and so on. Synthesis General synthetic methods are used for the organic synthesis of lactams. Beckmann rearrangement Lactams form by the acid-catalyzed rearrangement of oximes in the Beckmann rearrangement. Schmidt reaction Lactams form from cyclic ketones and hydrazoic acid in the Schmidt reaction. Cyclohexanone with hydrazoic acid, forms ε - Caprolactum, which upon treatment with excess acid forms Cardiazole, a heart stimulant. Cyclization of amino acids Lactams can be formed from cyclisation of amino acids via the coupling between an amine and a carboxylic acid within the s ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
