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Oxazolidinones are useful as Evans auxiliaries, which are of interest for chiral synthesis. In a common implementation, an acid chloride substrate reacts with a chiral oxazolidinone to form an imide. Substituents at the 4 and 5 position of the oxazolidinone direct any aldol reaction to the alpha position of the carbonyl of the substrate. [6]
The antimicrobial spectrum of an antibiotic can be determined by testing its antimicrobial activity against a wide range of microbes in vitro. Nonetheless, the range of microorganisms which an antibiotic can kill or inhibit in vivo may not always be the same as the antimicrobial spectrum based on data collected in vitro. [2] [5]
Glycopeptide antibiotics are a class of drugs of microbial origin that are composed of glycosylated cyclic or polycyclic nonribosomal peptides.Significant glycopeptide antibiotics include the anti-infective antibiotics vancomycin, teicoplanin, telavancin, ramoplanin, avoparcin and decaplanin, corbomycin, complestatin and the antitumor antibiotic bleomycin.
[1] [9] The results of antimicrobial susceptibility tests performed during a given time period can be compiled, usually in the form of a table, to form an antibiogram. [ 31 ] [ 32 ] Antibiograms help the clinician to select the best empiric antimicrobial therapy based on the local resistance patterns until the laboratory test results are available.
If a suspension used is too heavy or too dilute, an erroneous result (either falsely resistant or falsely susceptible) for any given antimicrobial agent could occur. Original McFarland standards were made by mixing specified amounts of barium chloride and sulfuric acid together.
An acetamide substituent on the 5-methyl group is the best choice in terms of antibacterial efficacy, and is used in all of the more active oxazolidinones developed thus far; in fact, straying too far from an acetamide group at this position makes the drug lose its antimicrobial power, although weak to moderate activity is maintained when some ...
Chiral auxiliaries are incorporated into synthetic routes to control the absolute configuration of stereogenic centers. David A. Evans' synthesis of the macrolide cytovaricin, considered a classic, utilizes oxazolidinone chiral auxiliaries for one asymmetric alkylation reaction and four asymmetric aldol reactions, setting the absolute stereochemistry of nine stereocenters.
Skeletal formula of tetracycline with atoms and four rings numbered and labeled.. Tetracyclines are a group of broad-spectrum antibiotic compounds that have a common basic structure and are either isolated directly from several species of Streptomyces bacteria or produced semi-synthetically from those isolated compounds. [1]