Investigation of the phase diagrams of chiral praziquantel

✍ Scribed by Yue Liu; Xin Wang; Jing-Kang Wang; Chi Bun Ching

• Publisher: John Wiley and Sons
• Year: 2006
• Tongue: English
• Weight: 126 KB
• Volume: 18
• Category: Article
• ISSN: 0899-0042
• DOI: 10.1002/chir.20251

✦ Synopsis

Abstract

In the present work, thermal properties of praziquantel, including melting point phase diagram and solubility, were determined for the purpose of exploration on an integrated enantioseparation process of chromatography and crystallization. The solubility of racemic praziquantel in methanol and 2‐propanol was measured in the temperature range between 0 and 40°C. In agreement with previous conclusions, the resulting phase diagram reveals the racemic compound behavior of praziquantel arising from the existence of eutectics. A ternary phase diagram of praziquantel enantiomers and the methanol system was also determined. Based on the information provided by the ternary solubility phase diagram, an optimized integrated enantioseparation process was suggested. Pure praziquantel crystals were recovered, and the crystal structure was solved by X‐ray crystallography. Chirality, 2006. © 2006 Wiley‐Liss, Inc.