Synthesis and in Vitro Cytotoxicity Profile of the <i>R</i>-Enantiomer of 3,4-Dihydroxymethamphetamine (<i>R</i>-(−)-HHMA): Comparison with Related Catecholamines
作者:Anne Felim、Guadalupe Herrera、Anne Neudörffer、Manuel Blanco、José-Enrique O’Connor、Martine Largeron
DOI:10.1021/tx9003374
日期:2010.1.18
(+/-)-3,4-Methylenedioxymethamphetamine (MDMA, also known as "ecstasy") is a chiral drug that is essentially metabolized in humans through O-demethylenation into 3,4-dihydroxymethamphetamine (HHMA). There has recently been a resurgence of interest in the possibility that MDMA metabolities, especially 5-(N-acetylcysten-S-yl)-N-methyl-alpha-methyldopamine (designated its 5-NAC-HHMA), might play it role in MDMA neurotoxicity. However, the chirality of MDMA was not considered in previously reported ill vivo Studies because HHMA, the precursor of the 5-NAC-HHMA metabolite, was used the racemate. Since the stereochemistry of this chiral drug needs to be considered, the first total Synthesis of R-(-)-HHMA is reported. Using L-DOPA as the chiral source, the preparation of R-(-)-HHMA is achieved through seven steps. in 30% overall yield and 99.5% enantiomeric excess. The cytotoxicity of R-(-)-HHMA and related catecholamines has been further determined by flow cytometric analysis of propidium iodide uptake in human dopaminergic neuroblastoma SH-SY5Y cells and by in Escherichia coli plate assay, specific for the detection of oxidative toxicity. The good correlation between the toxicities observed in bath systems suggests that. SH-SY5Y cells are sensitive to oxidative toxicity and that cell death (necrosis) would be mediated by reactive oxygen species mainly generated from redox active quinonoid centers. In contrast, apoptosis was detected for 3,4-dimethoxymethamphetamine (MMMA), the synthetic precursor of HHMA possessing it protected catechol group. MMMA was not toxic in the bacterial assay, indicating that its toxicity is not related to increased oxidative stress. Finally, we can conclude that there is a need to distinguish the toxicity ascribed to MDMA itself, also bearing it protected catechol moiety, from that depending oil MDMA biotransformation leading to catechol metabolites Such as HHMA and the thioether conjugates.
(+/−)-3,4-亚甲二氧基甲基苯丙胺(MDMA, 俗称“摇头丸”)是一种手性药物,在人体内主要通过脱甲氧基反应代谢为3,4-二羟基甲基苯丙胺(HHMA)。最近,人们对MDMA代谢产物(尤其是5-(N-乙酰半胱氨酸S-基)-N-甲基-a-甲基多巴胺,命名为5-NAC-HHMA)在MDMA神经毒性中可能起的作用重新产生了兴趣。然而,由于之前体外研究中使用的5-NAC-HHMA前体HHMA为外消旋体,因此未考虑MDMA的手性。由于需要考虑这种手性药物的立体化学,首次报道了R-(-)-HHMA的全合成。以L-DOPA为手性来源,通过七个步骤成功制备了R-(-)-HHMA,总产率为30%,对映体过量为99.5%。通过流式细胞术分析人多巴胺神经母细胞瘤SH-SY5Y细胞中碘化丙啶的摄入量,以及通过特定检测氧化毒性的大肠杆菌平板测试,进一步确定了R-(-)-HHMA及其相关儿茶酚胺的细胞毒性。两种测试系统中观察到的毒性的良好相关性表明,SH-SY5Y细胞对氧化毒性敏感,而细胞死亡(坏死)则主要由还原活性醌类中心产生的活性氧介导。相比之下,3,4-二甲氧基甲基苯丙胺(MMMA),即具有保护性儿茶酚基团的HHMA合成前体,在细菌测定中无毒性,表明其毒性与氧化应激增加无关。最后,我们可以得出结论,有必要区分归因于MDMA本身(也具有保护性儿茶酚基团)的毒性,以及依赖于MDMA生物转化生成儿茶酚代谢物(如HHMA和硫醚结合物)的毒性。