Цефаклор

Описание

Cefaclor differs from cephalexin primarily in the bio-isosteric replacement of methyl by chlorine at C-3 and is quite acid stable, allowing oral administration. It also is quite stable to metabolism. It is less active against Gram-negative bacteria compared with the other second-generation cephalosporins but is more active against Gram-negative bacteria compared with the first-generation drugs.

Химические свойства

white crystalline solid

Использование

Cefaclor belongs to the family of antibiotics known as the cephalosporins (cefalosporins). The cephalosporins are broad-spectrum antibiotics that are used for the treatment of septicaemia, pneumonia, meningitis, biliary-tract infections, peritonitis, and

Определение

ChEBI: A cephalosporin bearing chloro and (R)-2-amino-2-phenylacetamido groups at positions 3 and 7, respectively, of the cephem skeleton.

Антимикробная активность

It is less resistant than other group 2 cephalosporins to staphylococcal β-lactamase. It is active against N. gonorrhoeae and H. influenzae and against most enterobacteria, but it is susceptible to common enterobacterial β-lactamases. Pr. vulgaris and Providencia, Acinetobacter and Serratia spp. are resistant. B. fragilis and clostridia are resistant but other anaerobes are commonly susceptible.

Клиническое использование

Cefaclor (Ceclor) is an orally active semisyntheticcephalosporin that was introduced in the American market in1979. It differs structurally from cephalexin in that the 3-methyl group has been replaced by a chlorine atom. It issynthesized from the corresponding 3-methylenecepham sulfoxideester by ozonolysis, followed by halogenation of theresulting β-ketoester. The 3-methylenecepham sulfoxideesters are prepared by rearrangement of the corresponding 6-acylaminopenicillanic acid derivative. Cefaclor is moderatelystable in acid and achieves enough oral absorption to provideeffective plasma levels (equal to about two-thirds of thoseobtained with cephalexin). The compound is apparentlyunstable in solution, since about 50% of its antimicrobial activityis lost in 2 hours in serum at 37°C. The antibacterialspectrum of activity is similar to that of cephalexin, but it isclaimed to be more potent against some species sensitiveto both agents. Currently, the drug is recommended for thetreatment of non–life-threatening infections caused by H.influenzae, particularly strains resistant to ampicillin.

Побочные эффекты

Apart from mild gastrointestinal disturbance, the drug is well tolerated. Transiently increased transaminase levels and symptomatic vaginal candidosis have been noted. Clusters of a serum sickness-like illness have been described in children.

Профиль безопасности

Moderately toxic by intraperitoneal route. Human systemic effects by ingestion: joints, dermatitis, increased body temperature. An experimental teratogen. Experimental reproductive effects. When heated to decomposition it emits toxic fumes of Clí, SOx, an