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Levosimendan Form I, C14H12N6O.
Jacob K Salazar1, James A Kaduk2, Anja Dosen3
1North Central College, Department of Chemistry 131 S Loomis St Naperville IL 60540 USA.
Summary
The crystal structure of levosimendan Form I was solved using X-ray powder diffraction and density functional theory. This reveals its P212121 space group and layered molecular stacking stabilized by hydrogen bonds.
Area of Science:
- Crystallography
- Materials Science
- Computational Chemistry
Background:
- Levosimendan is a calcium sensitizer used in treating acute decompensated heart failure.
- Understanding the solid-state structure of drug compounds is crucial for formulation and bioavailability.
- Polymorphism in drug substances can significantly impact their physicochemical properties.
Purpose of the Study:
- To determine the crystal structure of levosimendan Form I.
- To elucidate the intermolecular interactions and packing in levosimendan Form I.
- To provide a structural basis for understanding levosimendan's solid-state behavior.
Main Methods:
- Synchrotron X-ray powder diffraction (XRPD) for crystal structure determination.
- Density Functional Theory (DFT) for structural optimization.
- Analysis of hydrogen bonding and molecular packing.
Main Results:
- The crystal structure of levosimendan Form I was solved and refined.
- Levosimendan Form I crystallizes in the P212121 space group.
- Molecules exhibit nearly parallel stacking along the bc plane, linked by N-H⋯O and N-H⋯N hydrogen bonds.
Conclusions:
- The detailed crystal structure of levosimendan Form I has been established.
- The identified hydrogen bonding patterns dictate the layered crystal packing.
- This structural information is vital for future pharmaceutical development and polymorph control of levosimendan.
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