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Streptogramin synthesis

Another example of macrocyclic RCM with a diene-ene was disclosed in 2000 by Meyers and coworkers in the first total synthesis of griseoviridin (223) [ 107]. Griseoviridin is a highly complex member of the family of streptogramin antibiotics, featuring a 23-membered unsaturated bis-lactam core incorporat-... [Pg.313]

Steps in bacterial protein synthesis and targets of (1) chloramphenicol (2) macrolides, clindamycin, and type B streptogramins and (3) tetracyclines. The 70S ribosomal mRNA complex is shown with its 50S and 30S subunits. The peptidyl tRNA at the donor site donates the growing peptide chain to the aminoacyl tRNA at the acceptor site in a reaction catalyzed by peptidyl transferase. The tRNA, discharged of its peptide, is released from the donor site to make way for translocation of the newly formed peptidyl tRNA. The acceptor site is then free to be occupied by the next "charged" aminoacyl tRNA. [Pg.1056]

The drugs described in this chapter are, like those described in Chapter 44 Chloramphenicol, Tetracyclines, Macrolides, Clindamycin, Streptogramins, protein synthesis inhibitors that interfere with ribosomal function. These agents are useful mainly against aerobic gram-negative microorganisms. [Pg.1071]

A complication attending the deprotection of MOM-protected 1,3-dioIs is formation of methylene acetals, which are very difficult to hydrolyse see Scheme 4.257 below). Ghosh and Liu were able to remove two MOM groups protecting a 1,3-diol in the final step of their synthesis of the streptogramin antibiotic Ma-dumycin II [Scheme 4.245],456 The successful method employed tetrabutylam-monium bromide 2 equiv) and an excess of dichlorodimethylsilane in dichloro-methane at 0 cC for 6 h. [Pg.295]

Mukhtar TA, Wright GD. Streptogramins, oxazolidinones, and other inhibitors of bacterial protein synthesis. Chem. Rev. 2005 105 529-542. [Pg.100]

In the laboratory of A.I. Meyers, the first enantioselective total synthesis of the streptogramin antibiotic (-)-madumycin II was achieved. The natural product contains an oxazole moiety, which may be considered a masked dehydropeptide. The oxazole moiety was introduced in two steps by the Burgess cyciodehydration reaction followed by oxidation of the resulting oxazoline to the corresponding oxazole. [Pg.73]

Two important new streptogramins are quinu-pristin (Fig. 10.15A) and dalfopristin (Fig. 10.15B), which are derivatives of pristinamycin I and IIA, respectively. Individually, the two components are bacteristatic but in combination they act synergistically to produce a bactericidal effect by inhibiting early (dalfopristin) and late (quinupristin) phases of bacterial protein synthesis. These two antibiotics are used intravenously in combination (ratio 30 70) for the treatment of serious or life-threatening infections associated with vancomycin-resistant Enterococcus faecium bacteraemia, although the effect against this organism is bacteristatic. [Pg.169]

The MLS (macrolides, lincosamides, streptogramins) group of antibiotics all inhibit protein synthesis by binding to the 50S ribosomal subunit. Resistance mechanisms specific to individual members occur but resistance to all may be conferred by a single mechanism that involves 23S rRNA. However, it is claimed that the quinupristin-dalfopristin combination does not demonstrate cross-resistance to other antibiotics within the MLS group or to other antibiotics. [Pg.169]

Inhibition of bacterial protein synthesis Aminoglycosides, chloramphenicol, macrolides, tetracyclines, streptogramins, linezolid... [Pg.189]

Macrolides inhibit growth of bacteria by inhibiting protein synthesis on ribosomes (17,415,416). Bacterial resistance to macrolides is often accompanied by cross-resistance to lincosamide and streptogramin B antibiotics (MLS-resistance), which can be either inducible or constitutive (417). 14-Membered macrolides generally induce resistance to themselves, whereas 16-membered macrolides do not consequendy, one advantage of the latter is their activity against bacteria which are inducibly resistant to erythromycin. Both 14- and 16-membered macrolides lack activity against constitutively resistant strains (387,388). [Pg.108]

Quinupristin/dalfopristin is a streptogramin. Quinupristin inhibits the late phase of protein synthesis dalfopristin inhibits the early phase of protein synthesis. It is indicated in the treatment of serious or life-threatening infections associated with VREF treatment of complicated skin and skin-structure infections caused by Staphylococcus aureus (methicillin-susceptible) or Streptococcus pyogenes. [Pg.611]

It is widely accepted that MLS antibiotics inhibit protein synthesis by binding to closely related sites on the 508 subunit of the 70S ribosome of bacteria [4], despite being structurally different from each other (see Figs. 1 and 2 in a later section). That is the reason why, when inducible resistant Staphylococcus aureus cells are exposed to a low concentration of the drug (0.05 tg erythromycin/ml - 6.8 x 10 M), they show resistance against not only erythromycin but also other macrolide antibiotics as well as lincosamide and type B streptogramin antibiotics. Erythromycin has been widely used and has been the object of extensive molecular and biological studies. [Pg.454]

Chloramphenicol Tetracyclines Macrolides Lincosamides Streptogramins Linezolid Figure 44-1. Bacteriostatic inhibitors of protein synthesis. [Pg.385]

Fluoroquinolones inhibit bacterial topoisomerases II and IV Streptogramins are recently introduced inhibitors of bacterial nucleic acid synthesis Vancomycin inhibits the synthesis of precursors of the linear peptidoglycan chains of the bacterial cell wall... [Pg.595]


See other pages where Streptogramin synthesis is mentioned: [Pg.108]    [Pg.152]    [Pg.11]    [Pg.55]    [Pg.56]    [Pg.358]    [Pg.352]    [Pg.44]    [Pg.52]    [Pg.245]    [Pg.1003]    [Pg.1442]    [Pg.876]    [Pg.3]    [Pg.7]    [Pg.230]    [Pg.791]    [Pg.363]    [Pg.791]    [Pg.11]    [Pg.536]    [Pg.556]    [Pg.228]    [Pg.124]    [Pg.152]    [Pg.1390]    [Pg.385]    [Pg.1647]   


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Streptogramins

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