Recently, two fluorine-18 labelled derivatives of flumazenil were described: 5-(2′-[18F]fluoroethyl)-5-desmethylflumazenil (ethyl 8-fluoro-5-[18F]fluoroethyl-6-oxo-5,6-dihydro-4H-benzo-[f]imidazo[1,5-a] [1,4]diazepine-3-carboxylate; [18F]FEFMZ) and 3-(2′-[18F]fluoro)-flumazenil (2′-[18F]fluoroethyl 8-fluoro-5-methyl-6-oxo-5,6-dihydro-4H-benzo-[f]imidazo[1,5-a]-[1,4]diazepine-3-carbo- xylate; [18F]FFMZ). Since the biodistribution data of the latter were superior to those of the former we developed a synthetic approach for [18F]FFMZ starting from a commercially available precursor, thereby obviating the need to prepare a precursor by ourselves. The following two-step procedure was developed: First, [18F]fluoride was reacted with 2-bromoethyl triflate using the kryptofix/acetonitrile method to yield 2-bromo-[18F]fluoroethane ([18F]BFE). In the second step, distilled [18F]BFE was reacted with the tetrabutylammonium salt of 3-desethylflumazenil (8-fluoro-5-methyl-6-oxo-5,6-dihydro-4H-benzo-[f]imidazo[1,5-a] [1,4]diazepine-3-carboxylic acid) to yield [18F]FFMZ. The synthesis of [18F]FFMZ allows for the production of up to 7 GBq of this PET-tracer, enough to serve several patients. [18F]FFMZ synthesis was completed in less than 80 min and the radiochemical purity exceeded 98%. Copyright © 2003 John Wiley & Sons, Ltd.
最近,描述了
氟马西尼的两种
氟18标记衍
生物:5-(2′-[18F]
氟乙基)-5-去甲基
氟马西尼(乙基8-
氟-5-[18F]
氟乙基-6-氧代-5,6-二氢) -4H-苯并-[f]
咪唑并[1,5-a][1,4]二氮杂-3-
羧酸酯;[18F]FEFMZ) 和 3-(2′-[18F]
氟)-
氟马西尼 (2′- [18F]
氟乙基 8-
氟-5-甲基-6-氧代-5,6-二氢-4H-苯并-[f]
咪唑并[1,5-a]-[1,4]二氮杂-3-
羧酸酯;[18F]FFMZ)。由于后者的
生物分布数据优于前者,我们开发了一种从市售前体开始合成[18F]FFMZ的方法,从而避免了自己制备前体的需要。开发了以下两步程序:首先,使用 kryptofix/
乙腈方法,[18F]
氟化物与
三氟甲磺酸 2-
溴乙酯反应,生成 2-
溴-[18F]
氟乙烷 ([18F]BFE)。第二步,蒸馏的[18F]BFE与3-去乙基
氟马西尼(8-
氟-5-甲基-6-氧代-5,6-二氢-4H-苯并-[f]
咪唑[1, 5-a][1,4]二氮杂-3-
羧酸)得到[18F]FFMZ。 [18F]FFMZ 的合成允许生产高达 7 GBq 的这种 PET 示踪剂,足以服务多名患者。 [18F]FFMZ合成在不到80分钟内完成,放射
化学纯度超过98%。版权所有 © 2003 约翰·威利父子有限公司