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Updated: Jun 19, 2026
11:27
A Package of Established Analytical Tools to Investigate the Solid-State Alteration of Lipid-Based Excipients
Published on: August 9, 2022
Three isostructural solvates of finasteride and their solid-state characterization
Nate Schultheiss1, Jared P Smit, Jason A Hanko
1SSCI, A Division of Aptuit, 3065 Kent Avenue, West Lafayette, IN 47906, USA. nathan.schultheiss@aptuit.com
Summary
Three new finasteride solvates were identified and characterized. Vacuum drying these finasteride forms yielded the anhydrous Form II, advancing pharmaceutical material science.
Area of Science:
- Pharmaceutical Science
- Crystallography
- Solid-State Chemistry
Background:
- Finasteride is a key pharmaceutical compound.
- Understanding its solid-state forms (solvates and anhydrous forms) is crucial for drug formulation and stability.
- Previous research has identified various finasteride solvates.
Purpose of the Study:
- To synthesize and characterize novel crystalline hemi-hydrate, channel solvates of finasteride.
- To investigate the structural relationship of these new solvates with previously reported finasteride solvates.
- To explore the conversion of these solvates into anhydrous finasteride forms.
Main Methods:
- Single-crystal X-ray diffraction for structural characterization.
- Solvate synthesis using acetone, methyl ethyl ketone (MEK), and toluene.
- Vacuum drying experiments to induce dehydration.
Main Results:
- Three isostructural finasteride solvates (acetone, MEK, and toluene) were successfully obtained and characterized.
- These new solvates are additional members of a known family of finasteride solvates.
- Anhydrous finasteride Form II was produced by vacuum drying the solvates at 85°C for 1 day.
Conclusions:
- The characterization of new finasteride solvates expands the understanding of its solid-state landscape.
- The conversion to anhydrous Form II demonstrates a viable method for obtaining a specific crystalline form.
- This study contributes to the knowledge base for finasteride's physical chemistry and potential pharmaceutical applications.
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