Difloxacin

The generally accepted structure-activity relationships developed in the early work in the quinolone series held that the N-1 substituent needed to be small and aliphatic. This picture was upset in a dramatic way with the discovery of the excellent potency and antimicrobial spectrum of difloxacin (45) and its congeners in which the substituent on N-1 is an aromatic ring. The synthe-... 

Alternately, amifloxacin can be prepared via the ofloxacin/difloxacin route using an addition-elimination reaction with unsymmetiical N-methyl-N-formyl hydrazone to give 49 [14]. 

A-56620) and (21 c) (difloxacin) were compared with the corresponding 1 -ethyl derivatives, norfloxacin and pefloxacin in mouse protection tests versus E. coli Juhl (Table 6.8). The two 7-(4-methylpiperazin-l-yl)quinolone derivatives, difloxacin and pefloxacin show enhanced oral activity relative to the 7-(piperazin-l-yl)quinolones, A-56620 and norfloxacin, respectively the absolute improvement in ED50 values in the 1-phenyl series is less dramatic. However, it should be noted that difloxacin, the more active agent in vivo, is 2 log2 dilutions less active in vitro. 

Further, the resulting principal components of the variables were used to assign the CNS activity of compounds in the test set low penetration (BBB-), medium permeability (BBB ), or ready absorbance (BBB+). Although some of the molecules were found to exhibit problems throughout all prediction approaches, the prediction was very good for the group of quinolones (difloxacin and related compounds), similar to the results of Crivori et al. and Rose et al. The CNS activity of the steroids also showed a clear differentiation between those that are readily absorbed and CNS-inactive compounds. 

Darodipine, 107 Dazoxiben, 91 Delapril, 58 Desciclovir, 165 Desipramine, 201 Desoximetasone, 70 Dezaguanine, 162,163 Dezocine, 59 Diazlquone, 51 Difloxacin, 143, 144, 145 Dilevalol, 20 Disoxarll, 86 Diuretic, 130,168 Domperidone, 133 Donetidine, 114 Dopamine, 20 Dopexamine, 22 Doxazosin, 148 Doxorubicin, 62 Dribendazole, 132 Duoperone, 199... 

Recent research on 4-quinolone-3-carboxylates has led to discovery of the fluoroquinolones, which are second-generation quinolones and include ciprofloxacin, danofloxacin, difloxacin, enrofloxacin, flumequine, marbofloxacin, norfloxacin, ofloxacin, and sarafloxacin. The main difference between classic quinolones and the fluoroquinolones is that the latter contain a fluorine atom at the C-3 position and a piperazinyl group at the C-7 position (Fig. 3.6). 

European Agency for the Evaluation of Medicinal Products (EMEA), in Difloxacin, Opinion of the Committee for Veterinary Medicinal Products on the Estabhshment of MRLs, EMEA/CVMP/164/96, London, UK (1996). 

Roybal et al. (188) developed another liquid chromatographic method for the determination of enrofloxacin, ciprofloxacin, sarafloxacin, and difloxacin in milk. In this method, a 5 ml milk sample is extracted twice with a mixture of... 

Fig. 29.6.2 Typical chromatograms of 10 ppb quinolones standard solution (A), a blank milk sample (B), and a milk sample (C) fortified with 20 ppb ciprofloxacin (1), enrofloxacin (2), sarafloxacin (3), and difloxacin (4). (Reprinted from Ref. 188. Copyright, (1997), by AOAC INTERNATIONAL.)...

The following QUINs and FQUINs could be analyzed pipemedic acid (PIP), enoxacin (ENO), norfloxacin (NOR), ciprofloxacin (CIPRO), lomefloxacin (LOME), desmethyl-danoflox-acin (DES), danofloxacin (DAN), enrofloxacin (ENRO), sarafloxacin (SARA), cinoxacin (CINO), oxolinic acid (OXO), nalidixic acid (NALA), flumequin (FLU), piromidic acid (PIRA), marbo-floxacin (MAR), difloxacin (DIFLX), decoquinate (DEC), and ofloxacin (OFLX). 

Difflam benzydamine. diflorasone flumethasone. diflorasone diacetate flumethasone. difloxacin [inn] (difloxacin hydrochloride [usan]) is a quinolinecarboxylic acid ANTIBACTERIAL (a DNA gyrase enzyme inhibitor). 

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