Aspects on the Mechanism of the 1-Phenyl-1<i>H</i>-pyrazolo[3,4-<i>b</i>]quinoxaline Formation

Condensation of D-glucose, o-phenylenediamine and N,N-benzylphenylhydrazine hydrochloride (NNBPHH) in a one-pot reaction, or condensation of 2-(D-arabino-tetritol-1-yl) quinoxaline and NNBPHH, gave 3-(D-erythro-glycerol-1- yl)-1-phenyl-1H-pyrazolo[3,4-b]quinoxaline. The structure of the latter was determined by 1H NMR spectroscopy and by synthesis using phenylhydrazine hydrochloride instead of NNBPHH. Condensation of D-glucose and 4,5-dichloro-o-phenylenediamine gave 6,7-dichloro-2-(D-arabino-tetritol-1-yl)quinoxaline, which upon condensation with NNBPHH gave the corresponding 6,7-dichloro-3-(D-erythro-glycerol-1-yl)-1-phenyl-1H-pyrazolo[3,4-b]quinoxaline. The structure and mechanism of formation of these compounds are discussed.

首批盐酸西布曲明2个去甲基衍生物化学对照品的研制

目的:建立供含量测定用的盐酸西布曲明两个去甲基衍生物(盐酸N-单去甲基西布曲明和盐酸N,N-双去甲基西布曲明)的首批化学对照品。方法:应用UV、IR、NMR和ESI-MS对盐酸N-单去甲基西布曲明和盐酸N,N-双去甲基西布曲明对照品进行结构鉴定,并采用HPLC法、醇中碱电位滴定法和高氯酸非水电位滴定法进行纯度分析和含量测定。结果:HPLC测得两者的纯度分别为99.15%和99.33%;醇中碱电位滴定法测得两者的含量分别为101.3%和101.2%;高氯酸非水电位滴定法测得两者的含量分别为101.2%和100.6%。结论:本文中建立的醇中碱滴定法简便、准确、无汞污染,适用于盐酸西布曲明2个去甲基衍生物的含量测定。盐酸N-单去甲基西布曲明和盐酸N,N-双去甲基西布曲明对照品的建立为减肥类保健食品中非法添加西布曲明衍生物的检测和监督提供有力支持。