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Cephem
Cephems are a sub-group of β-lactam antibiotics including cephalosporins and cephamycin Cephamycins are a group of β-lactam antibiotics. They are very similar to cephalosporins, and the cephamycins are sometimes classified as cephalosporins. Like cephalosporins, cephamycins are based upon the cephem nucleus. Unlike most cephalospo ...s. It is one of the most common 4-membered ring heterocycle. Produced by actinomycetes, cephamycins were found to display antibacterial activity against a wide range of bacteria, including those resistant to penicillin and cephalosporins. The antimicrobial properties of Cephem include the attachment to certain penicillin-binding proteins that are involved in the production of cell walls of bacteria. Research Researchers have developed antibiotics that include cephems and they have tried to test them clinically. Many of the antibiotics that are manufactured have different efficiencies based on the amount used, their strength, and their antib ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Beta-lactam Antibiotic
β-lactam antibiotics (beta-lactam antibiotics) are antibiotics that contain a beta-lactam ring in their chemical structure. This includes penicillin derivatives (penams), cephalosporins and cephamycins (cephems), monobactams, carbapenems and carbacephems. Most β-lactam antibiotics work by inhibiting cell wall biosynthesis in the bacterial organism and are the most widely used group of antibiotics. Until 2003, when measured by sales, more than half of all commercially available antibiotics in use were β-lactam compounds. The first β-lactam antibiotic discovered, penicillin, was isolated from a strain of ''Penicillium rubens'' (named as ''Penicillium notatum'' at the time). Bacteria often develop resistance to β-lactam antibiotics by synthesizing a β-lactamase, an enzyme that attacks the β-lactam ring. To overcome this resistance, β-lactam antibiotics can be given with β-lactamase inhibitors such as clavulanic acid. Medical use β-lactam antibiotics are indicated for ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Cephalosporin Core Structure
The cephalosporins (sg. ) are a class of β-lactam antibiotics originally derived from the fungus ''Acremonium'', which was previously known as ''Cephalosporium''. Together with cephamycins, they constitute a subgroup of β-lactam antibiotics called cephems. Cephalosporins were discovered in 1945, and first sold in 1964. Discovery The aerobic mold which yielded cephalosporin C was found in the sea near a sewage outfall in Su Siccu, by Cagliari harbour in Sardinia, by the Italian pharmacologist Giuseppe Brotzu in July 1945. Structure Cephalosporin contains a 6-membered dihydrothiazine ring. Substitutions at position 3 generally affect pharmacology; substitutions at position 7 affect antibacterial activity, but these cases are not always true. Medical uses Cephalosporins can be indicated for the prophylaxis and treatment of infections caused by bacteria susceptible to this particular form of antibiotic. First-generation cephalosporins are active predominantly against Gra ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Cephalosporin
The cephalosporins (sg. ) are a class of β-lactam antibiotics originally derived from the fungus ''Acremonium'', which was previously known as ''Cephalosporium''. Together with cephamycins, they constitute a subgroup of β-lactam antibiotics called cephems. Cephalosporins were discovered in 1945, and first sold in 1964. Discovery The aerobic mold which yielded cephalosporin C was found in the sea near a sewage outfall in Su Siccu, by Cagliari harbour in Sardinia, by the Italian pharmacologist Giuseppe Brotzu in July 1945. Structure Cephalosporin contains a 6-membered dihydrothiazine ring. Substitutions at position 3 generally affect pharmacology; substitutions at position 7 affect antibacterial activity, but these cases are not always true. Medical uses Cephalosporins can be indicated for the prophylaxis and treatment of infections caused by bacteria susceptible to this particular form of antibiotic. First-generation cephalosporins are active predominantly against ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Cephamycin Core Structure
Cephamycins are a group of β-lactam antibiotics. They are very similar to cephalosporins, and the cephamycins are sometimes classified as cephalosporins. Like cephalosporins, cephamycins are based upon the cephem nucleus. Unlike most cephalosporins, cephamycins are a very efficient antibiotic against anaerobic microbes. Cephamycins were originally produced by ''Streptomyces'', but synthetic ones have been produced as well. Cephamycins possess a methoxy group at the 7-alpha position. In addition, cephamycins have been shown to be stable against extended-spectrum beta-lactamase (ESBL) producing organisms, although their use in clinical practice is lacking for this indication. Examples Cephamycins include: * Cefoxitin * Cefotetan * Cefmetazole Cefmetazole is a cephamycin antibiotic, usually grouped with the second-generation cephalosporins. __TOC__ Adverse effects The chemical structure of cefmetazole, like that of several other cephalosporins, contains an ''N''-methylthiot ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Cephamycin
Cephamycins are a group of β-lactam antibiotics. They are very similar to cephalosporins, and the cephamycins are sometimes classified as cephalosporins. Like cephalosporins, cephamycins are based upon the cephem nucleus. Unlike most cephalosporins, cephamycins are a very efficient antibiotic against anaerobic microbes. Cephamycins were originally produced by '' Streptomyces'', but synthetic ones have been produced as well. Cephamycins possess a methoxy In organic chemistry, a methoxy group is the functional group consisting of a methyl group bound to oxygen. This alkoxy group has the formula . On a benzene ring, the Hammett equation classifies a methoxy substituent at the ''para'' position as ... group at the 7-alpha position. In addition, cephamycins have been shown to be stable against extended-spectrum beta-lactamase (ESBL) producing organisms, although their use in clinical practice is lacking for this indication. Examples Cephamycins include: * Cefoxitin * Cefote ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
