Norfloxacin sesquihydrate

Area of Science:

• Crystallography
• Materials Science
• Medicinal Chemistry

Background:

• Fluoroquinolone antibiotics are crucial in treating bacterial infections.
• Understanding the crystal structure of pharmaceuticals is vital for drug development and stability.
• The title compound is a derivative of fluoroquinolone antibiotics.

Purpose of the Study:

• To elucidate the crystal structure of 1-ethyl-6-fluoro-4-oxo-7-(piperazin-4-yl)-1,4-dihydro-quinoline-3-carboxylate sesquihydrate.
• To identify the intermolecular interactions governing the crystal packing.
• To characterize the role of water molecules in the crystal lattice.

Main Methods:

• Single-crystal X-ray diffraction was employed to determine the crystal structure.
• Hydrogen bonding networks were analyzed using crystallographic data.
• Disorder in the water molecules was modeled and refined.

Main Results:

• The crystal structure was determined for C(16)H(18)FN(3)O(3)·1.42H(2)O.
• N-H···O and O-H···O hydrogen bonds were identified as the primary intermolecular forces.
• A two-dimensional layered corrugated sheet structure parallel to the b axis was observed.
• Disordered water molecules with distinct occupancies (0.741 and 0.259) were present in the crystal lattice.

Conclusions:

• The hydrogen bonding interactions dictate the formation of a stable two-dimensional layered structure.
• The observed crystal packing provides insights into the solid-state properties of the fluoroquinolone derivative.
• Understanding the hydration and structural features is essential for optimizing pharmaceutical formulations.