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Updated: May 23, 2026
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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. I. Aripiprazole nitrate
Eleonora Freire1, Griselda Polla, Ricardo Baggio
1Gerencia de Investigación y Aplicaciones, Comisión Nacional de Energía Atómica and Escuela de Ciencia y Tecnología, Universidad Nacional General San Martín, Buenos Aires, Argentina. freire@tandar.cnea.gov.ar
Summary
The crystal structure of aripiprazole nitrate was determined. This antipsychotic drug
Area of Science:
- Crystallography
- Medicinal Chemistry
- Pharmacology
Background:
- Aripiprazole is an atypical antipsychotic medication.
- Understanding the crystal structure of drug salts is crucial for formulation and stability.
Purpose of the Study:
- To present the crystal structure of aripiprazole nitrate.
- To compare its molecular arrangement and intermolecular interactions with previously reported aripiprazole forms.
Main Methods:
- Single-crystal X-ray diffraction was used to determine the crystal structure.
- Analysis of bond distances, angles, torsion angles, and intermolecular interactions.
Main Results:
- The crystal structure of aripiprazole nitrate (AripH(+)·NO(3)(-)) was elucidated.
- Similar bond distances and angles were observed compared to other aripiprazole forms, with minor variations around the protonated nitrogen.
- Distinct molecular spatial arrangement and intermolecular interactions, including hydrogen bonding and π-π stacking, were identified due to the nitrate counter-ion and protonation.
- The structure forms [100] strips linked into undulating sheets parallel to (010).
Conclusions:
- The crystal structure of aripiprazole nitrate reveals specific intermolecular interactions and spatial arrangements.
- These findings contribute to the understanding of aripiprazole's solid-state properties and potential implications for drug formulation.
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