Erythromycin antimicrobial spectrum

Bioavailabihty of 38% and has similar antimicrobial spectrum as erythromycin but is more effective than erythromycin on gram-negative bacteria. Mostly excreted in feces although some low levels (approximately 6%) of the parent compound are excreted through the urine. 

Most of the data on rokitamycin have been published in Japanese and Italian journals. As a propionyl ester of leucomycin, rokitamycin has an antimicrobial spectrum similar to that of erythromycin, it is especially potent against L. pneumophila, M. pneumoniae, and Chlamydia. Like other 16-membered macrolides, it is active against bacteria that are inducibly resistant to erythromycin but inactive against strains that are constitutively resistant to macrolide-lincosamide-streptogramin B antibiotics. 

C37H67NO12 717.936 Prod, by Streptomyces erythreus and Saccharopolyspora erythraea. Shows similar antimicrobial spectrum as Erythromycin A broad spectrum of antimicrobial activity. Cryst. (Mc2CO). Sol. MeOH, Et20 fairly sol. H2O, hexane. 

Erythromycin, from the actinomycete Saccharo-polyspora (formerly Streptomyces) erythraea, is the first member of this family of antibiotics to be marketed and successfully used clinically to treat infections in humans. It has an antimicrobial spectrum at least as wide as the penicillins, and interestingly, from our perspective, it is often used as a replacement for patients allergic to that group of drags. Besides erythromycin, other members of the macrolide family of antibiotics that are clinically useful include azithromycin, clarithromycin, dirithromycin, roxithromycin, telithromycin (these six are approved by the FDA), oleandomycin, and spiramycin. Clarithromycin, dirithromycin, and roxithromycin and the azalide azithromycin are more recent members of the group and can be regarded as newer generation macrolide antibiotics. 

Antimicrobials. Aztreonam, cefamandole, chloramphenicol, ciprofloxacin, co-trimoxazole, erythromycin, fluconazole, itraconazole, ketoconazole, metronidazole, miconazole, ofloxacin and sulphonamides (including co-trimoxazole) increase anticoagulant effect by mechanisms that include interference with warfarin or vitamin K metabolism. Rifampicin and griseofulvin accelerate warfarin metabolism (enzyme induction) and reduce its effect. Intensive broad-spectrum antimicrobials, e.g. eradication regimens for Helicobacter pylori (see p. 630), may increase sensitivity to warfarin by reducing the intestinal flora that produce vitamin K. 

The role of enterococci in nosocomial infections is probably due to a variety of factors of which antimicrobial resistance appears to be a primary cause. Enterococci possess a broad spectrum of both natural (intrinsic) resistance and acquired (transferable) resistance (Franz et al. 2003). Examples of antibiotics to which the enterococci present an intrinsic resistance include the P-lactam antibiotics (third generation cephalosporins), sulphonamides and clindamycin and aminoglycosides in low levels (Eranz et al. 2003). Acquired resistance based on plasmids or transpo-sons acquisition has relevance for chloramphenicol, erythromycin, high levels of clindamycin, aminoglycosides, tetracycline, high levels of P-lactam antibiotics, fluoroquinolones and glycopeptides like vancomycin (Murray 1990 Leclercq 1997). In particular, vancomycin-resistant enterococci (VRE) pose a major problem... 

Clarithromycin and erythromycin have very similar spectrums of antimicrobial activity. The major advantage of clarithromycin is that it... 

Oleandomycin, a 14-membered ring macrolide antibiotic, was isolated in 1956 from fermentation broths of Streptomyces antibioticus [360]. Some years later, oleandomycin was assigned the structure 340 on the basis of its chemical degradation [361]. Oleandomycin is effective, but less potently, against the same spectrum of bacteria as erythromycin, namely Gram-positive bacteria such as staphylococci, streptococci, and pneumococci. The antimicrobial activity of oleandomycin, when combined with tetracycline, is potentiated. In fact, in such a combination it is sold as an antibacterial agent for upper and lower respiratory tract infection. 

Solithromycin (CEM-101, Figure 44.8) is a ketolide antibiotic undergoing clinical development for the treatment of community-acquired pneumonia. It is another example of semi-synthetic antimicrobial agents derived from erythromycin, which was designed to overcome erythromycin resistance in Streptococcus pneumoniae. The synthesis of solithromycin involves the introduction of the fluorine atom on the (3-keto ester moiety with Selectfluor in the presence of potassium tert-butoxide in tetrahydrofuran (THF). Solithromycin shows the greatest potency and widest spectrum of activity against respiratory tract... 

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