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Preparation of Stable Bicyclic Aziridinium Ions and Their Ring-Opening for the Synthesis of Azaheterocycles
Published on: August 22, 2018
Aripiprazole salts. II. Aripiprazole perchlorate
Eleonora Freire1, Griselda Polla, Ricardo Baggio
1Gerencia de Investigación y Aplicaciones, Centro Atómico Constituyentes, Comisión Nacional de Energía Atómica, Buenos Aires, Argentina. freire@tandar.cnea.gov.ar
Summary
The molecular structures of aripiprazole perchlorate and aripiprazole nitrate are nearly identical. Subtle differences in how their crystal structures pack lead to distinct two-dimensional arrangements.
Area of Science:
- Crystallography
- Medicinal Chemistry
- Solid-state Chemistry
Background:
- Aripiprazole is an atypical antipsychotic used to treat various mental health conditions.
- Understanding the solid-state structures of drug molecules is crucial for formulation and bioavailability.
- Previous studies have characterized the structure of aripiprazole nitrate.
Purpose of the Study:
- To determine and analyze the molecular and crystal structure of aripiprazole perchlorate.
- To compare the crystal structure of aripiprazole perchlorate with that of aripiprazole nitrate.
- To investigate the influence of different counter-ions on the packing and organization of aripiprazole salts.
Main Methods:
- Single-crystal X-ray diffraction was used to elucidate the molecular structure.
- Structural parameters such as bond distances, angles, and torsion angles were analyzed.
- Comparison of crystallographic data between aripiprazole perchlorate and aripiprazole nitrate.
Main Results:
- The molecular structure of aripiprazole perchlorate was determined.
- Aripiprazole perchlorate and aripiprazole nitrate exhibit highly similar molecular geometries.
- Both structures display comparable first-order packing motifs due to equivalent counter-ion positions.
- Despite similar motifs, the interactions lead to distinct two-dimensional array organizations.
Conclusions:
- The perchlorate and nitrate counter-ions do not significantly alter the core molecular structure of aripiprazole.
- The crystal packing of aripiprazole salts is sensitive to the specific counter-ion and its interactions.
- Differences in crystal organization can impact the physicochemical properties of the drug substance.
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