Moxifloxacinium chloride monohydrate.

Area of Science:

• Crystallography
• Medicinal Chemistry
• Structural Biology

Background:

• Moxifloxacin is a broad-spectrum fluoroquinolone antibiotic.
• Understanding its crystalline structure is crucial for pharmaceutical formulation and stability.

Purpose of the Study:

• To determine the detailed crystal structure of moxifloxacin hydrochloride monohydrate.
• To analyze the molecular arrangement and intermolecular interactions within the crystal lattice.

Main Methods:

• Single-crystal X-ray diffraction analysis was employed.
• The crystal structure was solved and refined to elucidate atomic positions and bonding.

Main Results:

• The asymmetric unit contains two moxifloxacin cations, two chloride ions, and two water molecules.
• Moxifloxacin cations exhibit planar quinoline rings and chair/half-chair conformations in the piperidine/pyrrolidine rings.
• Extensive hydrogen bonding networks, including O-H⋯O, O-H⋯Cl, and N-H⋯Cl, were identified, along with weak C-H⋯O and C-H⋯Cl interactions.

Conclusions:

• The crystal structure provides a precise molecular model of moxifloxacin hydrochloride monohydrate.
• The identified hydrogen bonding patterns are key to the compound's solid-state properties and stability.