title: Supramolecular structures and physicochemical properties of norfloxacin salts.
abstract: Seven new molecular salts of norfloxacin (1-ethyl-6-fluoro-4-oxo-7-piperazin-1-yl-1H-quinoline-3-carboxylic acid; abbreviated as NF) with various organic acids (adipic acid, mucic acid, o-OH-benzoic acid, m-OH-benzoic acid, p-OH-benzoic acid, naphthalene-1, 5-disulfonic acid and naphthalene-2-sulfonic acid) were synthesized and their crystal structures were determined by X-ray crystallography. Supramolecular structures and reccurring packing patterns are discussed to understand the influence of non-covalent interactions in determination of the crystal packing and hydrate inclusion. The formation of hydrates was commonly observed among various NF salts, except for the adipate salt which exists as an anhydrous form. The physicochemical properties of salts were fully characterized with a variety of analytical techniques, including powder X-ray diffraction (PXRD), Fourier transform IR (FT-IR), Raman spectroscopy, thermogravimetric analysis (TGA), differential scanning calorimetry (DSC), hot-stage microscopy (HSM) and dynamic vapour sorption (DVS) etc. The synthesized norfloxacin salts were found to have different physicochemical properties, superior solubility and hygroscopicity. Particularly, NF adipate was found to be a desirable candidate for further development.
authors: Pharmaceutical Analytical and Solid-State Chemistry Research Center, Shanghai Institute of Materia Medica, Chinese Academy of Sciences, 555 Zu Chong Zhi Road, Zhang Jiang High-Tech Park, Shanghai 201203, People's Republic of China.
authors: Yun
authors: Y
authors: Xu
authors: Pharmaceutical Analytical and Solid-State Chemistry Research Center, Shanghai Institute of Materia Medica, Chinese Academy of Sciences, 555 Zu Chong Zhi Road, Zhang Jiang High-Tech Park, Shanghai 201203, People's Republic of China.
authors: Linglei
authors: L
authors: Jiang
authors: Pharmaceutical Analytical and Solid-State Chemistry Research Center, Shanghai Institute of Materia Medica, Chinese Academy of Sciences, 555 Zu Chong Zhi Road, Zhang Jiang High-Tech Park, Shanghai 201203, People's Republic of China.
authors: Xuefeng
authors: X
authors: Mei
mesh_terms: D000900:Anti-Bacterial Agents / Q000737:chemistry*; D002152:Calorimetry, Differential Scanning; D018360:Crystallography, X-Ray; D006860:Hydrogen Bonding; D008958:Models, Molecular; D008968:Molecular Conformation; D009643:Norfloxacin / Q000031:analogs & derivatives* / Q000737:chemistry*; D012492:Salts; D012995:Solubility; D013818:Thermogravimetry
chemical_list: D000900:Anti-Bacterial Agents; D012492:Salts; D009643:Norfloxacin
keywords: active pharmaceutical ingredients (APIs); norfloxacin; polymorphs; salt formation; supramolecular structures