Degradation Kinetics of (±)-4′-Ethyl-2-methyl-3-(1-pyrrolidinyl)propiophenone Hydrochloride (HY-770) and Structure–Stability Relationship among its Analogues in Aqueous Solution
作者:Osamu Nagata、Tetsuya Terasaki、Etsuko Yada、Hitoshi Sato、Ikumi Tamai、Akira Tsuji
DOI:10.1002/jps.2600780115
日期:1989.1
The kinetics and pathways for degradation of (+/-)-4'-ethyl-2-methyl-3-(1-pyrrolidinyl)propiophenone hydrochloride (HY-770; 1), a newly developed muscle-relaxing agent, and its analogues were studied in aqueous solution at 50 degrees C, ionic strength 0.5 M, and pH 8.0-12.0. Compound 1 and its four analogues followed pseudo-first-order degradation kinetics at constant pH and temperature. From the analysis
新型肌肉松弛剂(+/-)-4'-乙基-2-甲基-3-(1-吡咯烷基)苯乙酮盐酸盐(HY-770; 1)的降解动力学和途径在50℃,离子强度为0.5M,pH为8.0-12.0的水溶液中对它们进行了研究。在恒定的pH和温度下,化合物1及其四个类似物遵循伪一级降解动力学。从pH降解速率曲线的分析中可以明显看出,对于1及其结构类似物3'-氟-2-甲基-3-(1-),发生了特定的氢氧离子催化的离子化和非离子化物质的降解。吡咯烷基)苯乙酮盐酸盐(HN-961; 5)。发现氢氧根离子催化的电离物质的降解比未电离物质快100倍,并且是pH值小于9.0时的主要过程。相反,1在50℃的0.5 M HCl中极其稳定,表明水合氢离子催化的降解和离子化物种的自发降解可忽略不计。在35-50℃和pH 9.0下降解1的Arrhenius图表明,表观活化能为22.0 kcal / mol。五个结构类似物的降解速率显着取决于分子中苯取代基的吸电子作用。