tailieunhanh - Ebook Kucers’ the use of antibiotics (7/E): Part 2

(BQ) Part 2 book “Kucers’ the use of antibiotics” has contents: Antifolate agents and other synthetic antibacterials, quinolones and fluoroquinolones, nitroimidazoles, anti-tuberculous drugs, polyenes, echinocandins, allylamines and benzylamine derivatives, and other contents. | 2:11 QUINOLONES AND FLUOROQUINOLONES 2:11A New and Commonly Used Fluoroquinolones 101 Ciprofloxacin Jason Kwong and M. Lindsay Grayson 1. DESCRIPTION Ciprofloxacin is a fluoroquinolone (also called 4-quinolone, or quinolone carboxylic acid) that was developed by Bayer Pharmaceuticals for both oral and parenteral use. It is one of the second generation of quinolones (others include norfloxacin, ofloxacin, pefloxacin, and enoxacin) that have substantially enhanced antibacterial activity, compared for example with nalidixic acid (the first quinolone antibiotic). Ciprofloxacin, previously known as Bay 09867, is chemically known as 1-cyclopropyl-6-fluoro-1,4-dihydro-4-oxo-7-(1-piperazinyl) 3-quinolone carboxylic acid hydrochloride (Wise et al., 1983), has the empirical formula C17H18FN3O3 and its molecular weight is . The chemical structure is shown in Figure . Although developed after norfloxacin, successful widespread clinical experience with ciprofloxacin has resulted in it being regarded as the classic fluoroquinolone, against which other later generation quinolones are to be compared. Similar to most other second-generation quinolones, it has a long half-life, allowing twice daily dosing and good penetration into human cells, thereby providing good activity against intracellular pathogens. It has good tissue penetration and high potency against most Gram-negative pathogens, with lesser activity against staphylococci, and borderline or poor activity against streptococci and anaerobes. In general, ciprofloxacin has 2- to 4-fold greater antimicrobial potency than norfloxacin, and considerably greater in vitro activity than cephalosporins and aminoglycosides against most Gram- NH N HO N F O O Figure . Chemical structure of ciprofloxacin. negative bacilli (Sanders et al., 1987; Hooper and Wolfson, 1993a; Moellering, 1993). Neu (1989a) and Mitscher et al. (1993) have extensively reviewed the relationship between quinolone structure and in .