Cephems cefazolin

Antibiotics based on a related ring system, termed the cephems (figure 23.2), are highly useful. Here the five-membered ring has been expanded to six and the double bond of the penems retained. These are the cephalosporins and include such important antibiotics as cephalothin (Keflin), cefazolin (Ancef), cephalexin (Keflex), cefamandole (Cefam), cefuroxime (Zinacef), cefeclor (Ceclor) and cefoxitin (Mefoxin). 

The substitution of the Mi l side chain and the presence of the 2-methyl-l,3,4-thiodiazole-5-thiole (MTD) side ring in position 3 of the cephem nucleus of cefotiam, cefonicid and cefazolin (Figure 3) induces weaker but similar effects to those caused by the M i l side ring. It appears that the ionization of the N-dim-ethylaminoethyl group attached to the N-methyl-tetrazole-thiol (NMTT) side chain of cefotiam enhances its secretory transport in kidney epitheUal cells [64]. 

Some cephem analogs (cephaprin sodium, cefuroxime sodium, cefotaxime sodium, cefoperazone sodium, cefadroxil, ceftazidime, cefazolin sodium and cefaclor) can be determined spectrophotometrically based on formation of ion-pair complex with ammonium reinecekate. In acidic medium at 25 + 2°C, as the reaction products, the complex, absorbing at 525 nm, was formed according to the scheme [49] ... 

In conditions of acidic hydrolysis, determination of cephem analogs took place. Vanadium(IV) after reduction from vanadium(V), reacted with forming degradation products. Colored complexes of some cephem analogs (cephalexin, cephaprine sodium, cefazolin sodium, cefotaxime) were found, absorbing at 515, 512, 518 and 523 nm, respectively (Fig. 19) [59]... 

Parker, C.E. Perkins, J.R. Tomer, K.B. Shida, Y. O Heira, K. Nanoscale packed capillary liquid chromatography-electrospray ionization mass spectrometry analysis of penicillins and cephems. J.Chromatogr., 1993, 616, 45-57 [capillary HPLC electrospray LC-MS serum also ampicillin, car-benicUlin, cefalothin, cefazolin, cefmenoxime, cefmetetzole, cefoperazone, cefotaxime, cefotiam, cefoxitin, cephalexin, cloxacillin, dicloxacillin, penicillin G, pipericillin, sulbenicillin]... 

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