Glycopeptide antibiotics teicoplanin

Two EPMEs were proposed for the assay of R-baclofen. The electrodes were designed using macrocyclic glycopeptide antibiotic, teicoplanin [45]. Acetonitrile was added to the teicoplanin to design a modified teicoplanin-based electrode. The linear concentration ranges for the proposed enantioselective, membrane electrodes were 10 7-10 4mol/L for teicoplanin-based electrode and 10 6-10 4mol/L for the electrode based on teicoplanin modified with acetonitrile. The slopes of the electrodes were 60.0 and 57.2 mV/pR-baclofen for teicoplanin and teicoplanin modified with acetonitrile-based electrodes, respectively. The enantioselectivity was determined over S-baclofen. The proposed electrodes can be employed reliably for the assay of R-baclofen raw material and from its pharmaceutical formulation, Norton-Baclofen tablets. 

Li TL, Huang F, Haydock SF et al (2004) Biosynthetic gene cluster of the glycopeptide antibiotic teicoplanin characterization of two glycosyltransferases and the key acyltransfer-ase. Chem Biol 11 107-119... 

Favero A. Effects of the new glycopeptide antibiotic teicoplanin on platelet function and blood coagulation. Antimicrob Agents Chemother 1987 31(10) 1609-12. 

Rundlet, K.L. Gasper, M.P. Zhou, E.Y. Armstrong, D.W. Capillary electrophoretic enantiomeric separations using the glycopeptide antibiotic, teicoplanin. Chirality 1996, 8, 88-107. 

A packed capillary and a microbore h.p.l.c.-FAB-m.s. system,which incorporates gradient elution, on-line u.v.-detection, and post-column matrix addition, has been demonstrated for the glycopeptide antibiotic teicoplanin." ... 

Macrocyclic glycopeptides. The first of these CSPs - based on the cavity of the antibiotic vancomycin bound to silica - was introduced by Armstrong [25]. Two more polycyclic antibiotics teicoplanin and ristocetin A, were also demonstrated later. These selectors are quite rugged and operate adequately in both normal-phase and reversed-phase chromatographic modes. However, only a limited number of such selectors is available, and their cost is rather high. 

Teicoplanin aglycone (TAG) is the aglycone portion of glycopeptide antibiotic TE A2-2, that is, it contains the same heptapeptide backbone of TE, but it lacks the sugar... 

The use of macrocyclic antibiotics as chiral selectors for HPLC was first proposed by Armstrong et al. [50] in 1994. The most successful of the CSPs are based on the glycopeptide antibiotics vancomycin, teicoplanin and ristocetin A and are commercially available through Advanced Separation Technologies Inc. (Astec Inc.) as Chirobiotic V , Chirobiotic 1 and Chirobiotic R , respectively. More recently, a number of other derivatives of these antibiotics have also been developed offering different stereoselectivities. A comprehensive handbook is now available from Astec Inc. [51 ] alongside a number of recent review articles... 

Teicoplanin is a glycopeptide antibiotic that is very similar to vancomycin in mechanism of action and antibacterial spectrum. Unlike vancomycin, it can be given intramuscularly as well as intravenously. Teicoplanin has a long half-life (45-70 hours), permitting once-daily dosing. This drug is available in Europe but has not been approved for use in the United States. 

Two EPMEs based on macrocyclic glycopeptide antibiotics—vancomycin and teicoplanin—were designed for the assay of acetyl-L-carnitine [44]. The linear concentration ranges for the proposed electrodes were 10 5-10-2 mol/L for the vancomycin-based electrode and 10 4-10-2 mol/L for the teicoplanin-based electrode, with slopes of 58.1 and 55.0mV/p(acetyl-L-camitine), respectively. The enantioselectivity was determined over D-carnitine. 

Three EPMEs based on macrocyclic glycopeptide antibiotics— vancomycin and teicoplanin (modified or not with acetonitrile)—were proposed for the determination of l- and D-enantiomers of methotrexate (Mtx) [48]. The linear concentration ranges for the proposed enantioselective membrane electrodes were between 10 6 and 10-3 mol/L for l- and D-Mtx. The slopes of the electrodes were 58.00 mV/pL-Mtx for vancomycin-based electrode, 57.60 mV/pD-Mtx for teicoplanin-based electrode and 55.40 mV/pD-Mtx for teicoplanin modified with acetonitrile-based electrode. The detection limits of the proposed electrodes were of 10 8 mol/L magnitude order. All proposed electrodes proved to be successful for the determination of the enantiopurity of Mtx as raw material and of its pharmaceutical formulations (tablets and injections). 

Figure 1.3 Chemical structures of glycopeptides antibiotics vancomycin (1) [1], eremomycin (2) [15a], ristocetin A (3) [15b], and teicoplanin (4) [15c],...

The SARs of glycopeptide antibiotics have mostly been studied with vancomycin and teicoplanin. Some other examples also comprise the glycopeptides eremomycin, baMmycin, ristocetin, and avoparcin. The reasons for the predominance of vancomycin and teicoplanin are that, particularly vancomycin (Vancomycin, Eli Lilly and Company) and teicoplanin (Targocid, Lepetit, Italy), are industrial large-scale fermentation products, and most of these studies were performed within research programs or with the participation of researchers from Eli Lilly and Lepetit. 

Scheme 2-9. Semisynthetic modifications of vancomycin-type glycopeptide antibiotics, (a) Alterations and modifications of amino acids, (b) Attachment of molecules to the amino groups, to the carboxy groups, and to phenolic carbohydrate functionalities. Similar modifications have been performed for antibiotics of the teicoplanin-type.

There are literally hundreds of glycopeptide antibiotics, from which vancomycin, teicoplanin, and subsequently risuxretin A (for structures see Fig. 9.18) have been commercialized by Astec as Chirobiotic V, ChiiX)biotic T. and Chirobiotic R. More recently, avoparcin (see Fig. 9.18) has also been successfully applied as a chiral selector [280],... 

Teicoplanin can be nephrotoxic, but less often than vancomycin (6). However, concomitant aminoglycoside therapy in some patients makes the contribution of the glycopeptide antibiotic difficult to assess. Renal toxicity was observed more often in patients receiving the combination of netilmicin plus vancomycin than in patients treated with netilmicin plus teicoplanin (35). Similar differences in nephrotoxicity between vancomycin and... 

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