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Anise oil as para-methoxyamphetamine (PMA) precursor 总被引:1,自引:0,他引:1
These days, MDMA is one of the most popular drugs of abuse. Due to its illegality, MDMA and its chemical precursors are watched by governmental organizations in many countries. To avoid conflicts with legal instances, underground chemists have tried to market several new unregulated amphetamine analogues, such as 4-MTA. Para-methoxyamphetamine (PMA), on the other hand, is regulated by law but its precursors are easily obtained since they are cheap and unwatched. This article presents such a case, namely the large scale synthesis of PMA using anethole, a main constituent of anise oil, as precursor. Anethole has been converted to its phenyl acetone analogue via peracid oxidation, while PMA itself has been synthesized using this ketone as precursor in the Leuckart synthesis. The synthesis of PMA using anethole as starting product has been investigated applying GC/MS and GC-HSPME/MS techniques, hereby discovering new specific (4-methoxyphenol) and already identified synthesis impurities (4-methyl-5-(4-methoxyphenyl)pyrimidine, N-(beta-4-methoxyphenylisopropyl)-4-methoxybenzyl methyl ketimine, 1-(4-methoxyphenyl)-N-(2-(4-methoxyphenyl)-1-methylethyl-2-propanamine, 1-(4-methoxyphenyl)-N-methyl-N-(2-(4-methoxyphenyl)-1-methylethyl-2-propanamine, N-(beta-4-methoxyphenylisopropyl)-4-methoxybenzaldimine). The new impurity 4-methoxyphenol is specific for the application of a peracid oxidation method where anethole is used as precursor. 相似文献
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杨建光 《陕西行政学院学报》2003,17(2)
中国已经加入世界贸易组织。要减少加入WTO对农业所产生的冲击,必须实现跨越式发展。而以信息化技术为先 导的农业商新技术将为这次跨越武发展提供机遇。因此,要抓住这一有利时机,加快农业信息化步伐,全面推动现代农业信息技 术在整个农业领域的渗透和应用,促进农业实现“两个根本性转交”,促进农业现代化的早日实现。 相似文献
726.
目的研究尸体玫瑰齿现象与死因的关系及其法医学意义。方法采用观察法研究各种死因的大鼠尸体玫瑰齿现象。每种死因观察10只大鼠,其中8只死后即刻取牙齿观察(非腐败组),2只死后置水中腐败出现尸臭时取牙齿观察(腐败组),观察后立即将牙齿置于酒精中浸泡,分别于不同浸泡时间再进行观察。结果各种死因非腐败组即刻取牙观察均未见玫瑰齿现象,但置酒精中浸泡后均逐渐出现玫瑰齿现象,并在浸泡4h后玫瑰齿颜色显著;腐败组取牙齿后即刻观察均见玫瑰齿现象,置酒精浸泡1h后颜色不改变;腐败组较非腐败组颜色明显。结论尸体玫瑰齿现象与死因无关,不能作为法医学鉴定死因的依据。 相似文献
727.
Niewoehner L Andrasko J Biegstraaten J Gunaratnam L Steffen S Uhlig S 《Journal of forensic sciences》2005,50(4):877-882
Within the framework of the ENFSI Expert Working Group "Firearms," every second year, a proficiency test on the detection and identification of GSR by SEM/EDX is carried out. This proficiency test is a development and extension of the previous proficiency test GSR2001. The test material was again designed by the organization panel and manufactured by an external company for SEM accessories. This time the participating laboratories were requested to determine the total number of PbSbBa containing particles on a test sample following their own laboratory specific methods of automated GSR particle search and detection by SEM/EDX. One synthetic particle sample (SPS) with artificial GSR particles was dispatched to all participants. This paper summarizes the results of the study and assesses the overall performance of the participating laboratories. Furthermore an extended statistical evaluation and a comparison with previous studies was carried out. 相似文献
728.
The tissue distribution of ethyl acetate and ethanol in a case of acute intoxication by ethyl acetate is presented. The victim was a 39-year-old man who was found dead lying on his abdomen in the interior of a tank containing ethyl acetate. Confirmation of ethyl acetate was obtained with static headspace gas chromatography with mass spectrometry. In blood, rapid biotransformation of ethyl acetate occurs by plasma esterases resulting in acetic acid and ethanol. Quantitation of ethyl acetate and ethanol in the postmortem samples was performed using static headspace gas chromatography with flame ionization detector. N-butanol was used as internal standard. Separation of the compounds was obtained on a Supelcowaxtrade mark-10 Fused Silica capillary column. The method was linear over the specific ranges investigated and showed a within-run accuracy of 99.8 and 101.0% and a precision of 0.5 and 2.0% for ethanol and ethyl acetate, respectively. The postmortem samples were analyzed in duplicate or triplicate. Coefficients of variation were < or =4.51% for ethyl acetate and < or =0.52% for ethanol. The low ratios of the ethyl acetate concentration to the ethanol concentration found in the postmortem tissue samples confirmed the rapid in vivo biotransformation of ethyl acetate. The highest concentration of ethyl acetate was found in the testis indicating that postmortem percutane absorption may have occurred. To our knowledge, this is the first reported tissue distribution study of ethyl acetate and ethanol in a case of acute intoxication by ethyl acetate. 相似文献
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