通过使用多组分软件的紫外分光光度法研究咪达唑仑在不同pH值介质中的溶解度和酸碱行为。

Solubility and acid-base behaviour of midazolam in media of different pH, studied by ultraviolet spectrophotometry with multicomponent software.

作者信息

Andersin R

机构信息

Department of Pharmacy, University of Helsinki, Finland.

出版信息

J Pharm Biomed Anal. 1991;9(6):451-5. doi: 10.1016/0731-7085(91)80246-6.

DOI:10.1016/0731-7085(91)80246-6

PMID:1747397

Abstract

The solubility of midazolam is less than 0.1 mg ml-1 at neutral pH and it increases considerably in acidic media. A pKa value of 6.04 at 24 +/- 1 degree C was calculated from the solubility data. In acidic media midazolam is reversibly converted to the corresponding benzophenone (open-ring form). The extent of this reaction was investigated by assaying the two compounds simultaneously by UV spectrophotometry with multicomponent software. The structure of the benzophenone derivative was verified by IR, MS and 1H and 13C NMR spectrometry.

摘要

咪达唑仑在中性pH下的溶解度小于0.1mg/ml，在酸性介质中溶解度显著增加。根据溶解度数据计算出在24±1℃时的pKa值为6.04。在酸性介质中，咪达唑仑可逆地转化为相应的二苯甲酮（开环形式）。通过使用多组分软件的紫外分光光度法同时测定这两种化合物，研究了该反应的程度。通过红外光谱、质谱以及1H和13C核磁共振光谱对二苯甲酮衍生物的结构进行了验证。