Stereoisomeric separation and toxicity of a new organophosphorus insecticide chloramidophos.
Stereoisomeric separation and toxicity of a new organophosphorus insecticide chloramidophos.
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DOI：
10.1021/tx600281n
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发表时间：
2007-03
影响因子：
4.1
通讯作者：
Shanshan Zhou;Kunde Lin;Huayun Yang;Ling Li;Weiping Liu;Jian Li
中科院分区：
文献类型：
--
作者：
Shanshan Zhou;Kunde Lin;Huayun Yang;Ling Li;Weiping Liu;Jian Li
氯胺磷(CP)，O，S-dimethyl-[(2，2，2)-trichloro-1-hydroxyethyl]phosphoramidothioate，是一种新型的有机磷农药，在磷和碳原子上各有两个手性中心。虽然CP在中国的一些省份得到了广泛的应用，但人们对它的环境行为，特别是立体专一性的关注非常有限。本研究对环磷酰胺的立体异构体分离及毒性进行了研究。在Chiralpak AD色谱柱上，CP的四种立体异构体均被高效液相色谱分离。立体异构体(PK1~PK4)在质量谱和圆二色谱上有明显区别。用光学纯的CP立体异构体测定其对乙酰胆碱酯酶(AChE)的体外抑制作用和对大型水蚤(Daphnia Magna)的体内急性水生毒性，表明其具有立体选择性。对乙酰胆碱酯酶的抑制作用按PK4>、PK3>、PK2>、PK1的顺序递减。与之相比，对马尾藻的急性毒性依次为PK3>、PK2>、PK1>、PK4。这些结果表明，手性OP的整体毒性应该使用它们各自的对映体来评估。
Chloramidophos (CP), O,S-dimethyl-[(2,2,2)-trichloro-1-hydroxyethyl]phosphoramidothioate, is a new organophosphorus pesticide (OP) with two chiral centers each on the phosphorus and carbon atoms. Although CP has been widely used in some provinces of China, it has received very limited attention toward its environmental behaviors, in particular, with regard to stereospecificity. In this study, the stereoisomeric separation and toxicity of CP were investigated. All of the four stereoisomers of CP were successfully separated by high-performance liquid chromatography on a Chiralpak AD column. The stereoisomers (pk 1 to pk 4) were distinguishable on their mass and circular dichroism spectra. The inhibition on acetylcholinesterases (AChE, in vitro) and the acute aquatic toxicity to Daphnia magna (in vivo) tested with optically pure stereoisomers of CP showed its stereoselectivity. The inhibitory potency toward AChE decreased in the order of pk 4 > pk 3 > pk 2 > pk 1. In comparison, the acute toxicity to D. magna was in the order of pk 3 > pk 2 > pk 1 > pk 4. The stereoselectivity was found to be isomer-dependent, with 1.1-18.1-fold differences (in vitro) and 1.2-13-fold differences (in vivo) among the stereoisomers. These results suggest that the overall toxicity of chiral OPs should be assessed using their individual enantiomers.