核磁共振氢谱内标法测定茚地普隆的含量

Determination of Indiplon by Proton Nuclear Magnetic Resonance Spectrometry with Internal Standard Method

建立了测定无对照品的新型非苯二氮唑类镇静催眠药茚地普隆含量的快速、专属、简单的核磁共振氢谱内标法。用Varian Mercury Plus400MHz核磁共振谱仪,在25℃、以氘代氯仿为溶剂、3,4-二硝基甲苯为内标、观察频率400.121MHz、谱宽6410Hz、90°脉冲宽度6.45μs、采集时间4s和延迟时间15s的条件下采集试样的氢谱。以化学位移分别在δ8.72和δ8.72处的茚地普隆和3,4-二硝基甲苯的单峰作为定量峰,其峰面积比(As/Ar,y)与其质量比(ms/mr,x)的线性回归方程为y=6.1458x+0.0055,相关系数为r=0.99996,含量测定重复性实验的RSD为0.29%(n=6)。分析结果表明,在没有对照品的情况下,核磁共振氢谱内标法,可用于茚地普隆的含量测定和质量控制。

A rapid, specific and simple method was established for the determination of indiplon, a novel pyrazolopyrimidine sedative-hypnotic. ^1H NMR spectra were obtained in CDC13 with a Varian Mercury Plus 400 MHz spectromrter at 25℃. For each sample, 64 scans were recorded with the following parameters： observing frequency, 400.121 MHz; spectra width, 6410 Hz; 90° pulses width, 6.45μs ; acquisition time, 4 s; and delay time, 15 s. The analysis of ^1H NMR spectrum of indipion mixed with 3,4-dinitrotoluene （3,4- DNT） as internal standard in CDC13 revealed that the integration of signals at δ8.72 of indiplon and δ2.55 of 3,4-DNT could be used for the quantification. Linear regression of quantitative peak areas ratio （As/Ar, y） of indiplon-3,4-DNT versus mass ratio （ms/mr, x） yielded a correlation coefficient of 0.99996 and a regression equation of y =6.1458 x ＋0.0055, the precision RSD is 0.29% （n=6）. The results showed that ^1H NMR can be used for the quantitative determination and quality control of indiplon.