[18F]2-Fluoroethyl tosylate ([18F]FEOX, X=Ts) is widely used for labeling radiotracers for positron emission tomography (PET). Little work has been reported on syntheses of other [18F]2-fluoroethyl arylsulfonates ([18F]FEOX) that bear a less electron-rich aryl group, even though these might offer enhanced reactivities. Thus, a series of novel [18F]FEOX (X=benzenesulfonyl, brosyl, nosyl, 3,4-dibromobenzenesulfonyl) were synthesized and reactivities compared to [18F]FEOTs. Precursors for radiolabeling (bis-ethylene glycol arylsulfonates) and reference FEOX were synthesized (alcohol+arylsulfonyl chloride+KOSiMe3 in THF). Regardless of substitution pattern, [18F]FEOX (110°C, 5 min, acetonitrile) were obtained in similar decay-corrected isolated radiochemical yields (RCY; 47–53%). All [18F]FEOX gave excellent RCYs (64–87%) of the dopamine uptake radioligand, [18F]FECNT (130°C, 10 min, acetonitrile). The 3,4-dibromobenzensulfonate gave the highest RCY of [18F]FECNT (87%) and this HPLC-purified labeling agent was used directly for efficient [18F]FECNT production. When the secondary aniline of an amyloid probe (HM-IMPY) or p-nitrophenol was reacted with [18F]FEOX, RCYs were appreciably higher for brosylate and nosylate than for tosylate, while 3,4-dibromobenzenesulfonate again gave the highest RCY. Owing to the high reactivity of the new [18F]FEOX and their ease of syntheses via stable precursors, such agents (particularly 3,4-dibromobenzenesulfonate) should be considered as alternatives to [18F]FEOTs. Copyright © 2005 John Wiley & Sons, Ltd.
[18F]2-
氟乙基对
甲苯磺酸酯([18F]F
EOX, X=Ts)广泛用于正电子发射断层扫描(PET)示踪剂的标记。尽管可能具有增强的反应性,但关于合成其他[18F]2-
氟乙基芳
磺酸酯([18F]F
EOX)的研究报道很少,特别是含有较少电富集芳基的化合物。因此,合成了一系列新型[18F]F
EOX(X=苯磺酰基、对
溴苯磺酰基、对
硝基苯磺酰基、
3,4-二溴苯磺酰基)并比较了其与[18F]F
EOTs的反应活性。放射性标记前体(双
乙二醇芳
磺酸酯)和参考F
EOX通过以下方法合成:
乙醇+芳
磺酰氯+KOSiMe3(在
四氢呋喃中)。无论取代模式如何,[18F]F
EOX(110°C, 5 min,
乙腈)均以相似的衰减校正的放射
化学产率(RCY; 47–53%)获得。所有[18F]F
EOX均提供了优异的
多巴胺摄取放射
配体[18F]F
ECNT的RCY(64–87%)(130°C, 10 min,
乙腈)。
3,4-二溴苯磺酸酯提供了最高的[18F]F
ECNT的RCY(87%),该高效
液相色谱纯化的标记试剂直接用于高效生产[18F]F
ECNT。当与淀粉样蛋白探针(HM-IMPY)的二级
苯胺或
对硝基苯酚反应时,[18F]F
EOX的RCY明显高于对
溴苯磺酸酯和对硝基
苯磺酸酯,而
3,4-二溴苯磺酸酯再次提供了最高的RCY。由于新型[18F]F
EOX的高反应性和通过稳定前体合成的简便性,这些试剂(特别是
3,4-二溴苯磺酸酯)应被视为[18F]F
EOTs的替代品。版权所有 © 2005 John Wiley & Sons, Ltd.