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Polymorphism of tedisamil dihydrochloride
J O Henck1, E Finner, A Burger
1Institut für Pharmakognosie der Universität Innsbruck, Josef-Moeller-Haus, Innrain 52, A-6020 Innsbruck, Austria. Jan-Olav.Henck.JH@bayer-ag.de
Journal of Pharmaceutical Sciences
|August 16, 2000
Summary
Tedisamil dihydrochloride exhibits three solid polymorphic forms. Modification II is the stable form at room temperature, while others are of analytical interest due to instability.
Area of Science:
- Solid-state chemistry
- Pharmaceutical sciences
Background:
- Polymorphism significantly impacts drug properties and efficacy.
- Understanding crystal forms is crucial for pharmaceutical development and quality control.
Purpose of the Study:
- To characterize the polymorphic forms of tedisamil dihydrochloride.
- To determine the thermodynamic relationships and stability of these crystal forms.
Main Methods:
- Thermomicroscopy
- Differential scanning calorimetry (DSC)
- Vibrational spectroscopy
- Solid-state nuclear magnetic resonance (NMR)
- X-ray powder diffractometry (XRPD)
Main Results:
- Tedisamil dihydrochloride exists in three enantiotropically related polymorphic forms.
- Modification II is the thermodynamically stable form at 20°C.
- Transitions were observed between forms, with specific temperature ranges and enthalpy changes noted.
Conclusions:
- The study elucidates the polymorphic landscape of tedisamil dihydrochloride.
- Modification II is the preferred form for manufacturing due to its stability.
- Unstable forms (I and III) hold analytical significance.
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