Kawakami Kohsaku, Ida Yasuo, Yamaguchi Tohru
Developmental Research Laboratories, Shionogi & Co., Ltd., 12-4 Sagisu 5-chome, Fukushima-ku, Osaka, 553-0002, Japan.
Pharm Res. 2005 Aug;22(8):1365-73. doi: 10.1007/s11095-005-5275-7. Epub 2005 Aug 3.
Effect of salt type on hygroscopicity was evaluated using S-3578 salts.
The hydration behavior of a sulfate and a nitrate salt of S-3578 were evaluated by powder X-ray diffraction (PXRD), simultaneous measurement of PXRD-differential scanning calorimetry (DSC), moisture sorption analysis, simultaneous measurement of thermogravimetric/differential thermal analyses, and solid state 13C-nuclear magnetic resonance (C-NMR).
The sulfate salt incorporated two types of lattice water to form a monohydrate or a trihydrate. Additional water could also be absorbed as channel water to expand the lattice structure. The activation energy for dehydration was very high, probably due to steric hindrance in the lattice structure. The nitrate salt incorporated only one water molecule per compound as the lattice water. The additional water was absorbed as channel water as observed for the sulfate salt. X-ray diffractograms showed little dependence on the salt type under the ambient condition. The hydration number was likely to be affected by the size of the counter acids.
The hygroscopicity of S-3578 salts was significantly altered by the salt type. The difference in the amount of the lattice water could be explained in terms of the difference in the molecular size of the counter acids.
使用S - 3578盐评估盐类型对吸湿性的影响。
通过粉末X射线衍射（PXRD）、PXRD - 差示扫描量热法（DSC）同步测量、水分吸附分析、热重/差热分析同步测量以及固态13C - 核磁共振（C - NMR）来评估S - 3578的硫酸盐和硝酸盐的水合行为。
硫酸盐结合了两种类型的晶格水形成一水合物或三水合物。额外的水也可作为通道水被吸收以扩展晶格结构。脱水的活化能非常高，可能是由于晶格结构中的空间位阻。硝酸盐每个化合物仅结合一个水分子作为晶格水。如硫酸盐那样，额外的水作为通道水被吸收。在环境条件下，X射线衍射图显示对盐类型的依赖性很小。水合数可能受抗衡酸大小的影响。
S - 3578盐的吸湿性因盐类型而显著改变。晶格水含量的差异可以根据抗衡酸分子大小的差异来解释。
