Abstract The solid–liquid equilibria of a poorly soluble drug namely dipyridamole were assayed to determine solubility in pure and binary mixtures between 273.15 K and 313.15 K under atmospheric pressure. The solubility profiles of dipyridamole in pure and mixed solvents were evaluated by some thermodynamic models. The maximum solubility in mole fraction was obtained in pure N-methyl pyrrolidone (NMP) in all tested solvents. In mixtures of (NMP + isopropanol), the values increased monotonically with the increasing temperature and mass fraction of NMP. The Kamlet, Abboud and Taft Linear Solvation Energy Relationship (KAT-LSER) model was applied to analyze the effect of the solute–solvent intermolecular interactions on the solubility. The results of dissolution thermodynamic properties indicate that the dissolution behavior were endothermic and entropy-driven in all tested solvents. The experimental solubility data and mathematically correlated equations of dipyridamole estimated in this work may be useful for studies on the crystallization process of the final step of dipyridamole synthesis, for the purification dipyridamole of pharmaceutical applications.

中文翻译：

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双嘧达莫II型在纯溶剂和（N-甲基吡咯烷酮+异丙醇）混合物中的固液平衡和热力学性质

摘要 测定难溶性药物双嘧达莫的固液平衡，以确定在大气压下 273.15 K 和 313.15 K 之间的纯和二元混合物中的溶解度。通过一些热力学模型评估双嘧达莫在纯溶剂和混合溶剂中的溶解度曲线。在所有测试溶剂中，在纯 N-甲基吡咯烷酮 (NMP) 中获得最大摩尔分数溶解度。在（NMP + 异丙醇）的混合物中，这些值随着温度和 NMP 质量分数的增加而单调增加。应用 Kamlet、Abboud 和 Taft 线性溶剂化能关系 (KAT-LSER) 模型来分析溶质 - 溶剂分子间相互作用对溶解度的影响。溶解热力学性质的结果表明，溶解行为在所有测试溶剂中都是吸热和熵驱动的。在这项工作中估计的双嘧达莫的实验溶解度数据和数学相关方程可能有助于研究双嘧达莫合成最后一步的结晶过程，用于药物应用的纯化双嘧达莫。