Structure of two new compounds of fluoroquinolone antibiotics with mineral acids

New compounds of sparfloxacin (C₁₉H₂₂F₂N₄O₃, SfH) and levofloxacin (C₁₈H₂₀FN₃O₄, LevoH) with mineral acids, namely, sparfloxacinium bromide (SfH · HBr, I) and levofloxacindium diperchlorate (LevoH · 2HClO₄, II), have been synthesized and characterized by X-ray diffraction. Crystallographic data are a = 7.7151(7) Å, b = 26.109(3) Å, с = 10.008(1) Å, β = 103.556(1)°, V = 1959.7(3) ų, space group P2₁/n, Z = 4 for I and a = 9.727(6) Å, b = 20.440(12) Å, с = 12.286(7) Å, β = 104.327(8)°, V = 2367(2)ų, space group P2₁, Z = 4 for II. The structures of these compounds are stabilized by intra- and intermolecular hydrogen bonds and π–π interaction between SfH₂⁺ or LevoH₃²⁺ ions.