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Updated: Sep 28, 2025
Application and Methodology of the Non-destructive 19F Time-domain NMR Technique to Measure the Content in Fluorine-containing Drug Products
Published on: August 22, 2017
Ciprofloxacin salt and salt co-crystal with di-hydroxy-benzoic acids
Yuda Prasetya Nugraha1, Haruki Sugiyama2,3, Hidehiro Uekusa4
1Department of Pharmaceutics, School of Pharmacy, Bandung Institute of Technology, Bandung 40132, Indonesia.
Abstract:
The crystal structure of two multi-component crystals of ciprofloxacin [systematic name: 1-cyclo-propyl-6-fluoro-4-oxo-7-(piperazin-1-yl)quinoline-3-carb--oxy-lic acid], a fluoro-quinolone anti-biotic, namely, ciprofloxacin 2,6-di-hydroxy-benzoate salt, C17H19FN3O3 +·C7H5O4 -, (I), and ciprofloxacin hydro-chloride-3,5-di-hydroxy-benzoic-water (1/1/1), C17H19FN3O3 +·Cl-·C7H6O4·H2O, (II), were determined. In (I) and (II), the ciprofloxacin cations are connected via head-to-tail N-H⋯O hydrogen bonding. Both structures show an alternating layered arrangement between ciprofloxacin and di-hydroxy-benzoic acid.
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