...
  • 主题
高级搜索  >
历史搜索 清空历史
首页> 外文期刊>Journal of Labelled Compounds and Radiopharmaceuticals >Mechanistic approach of the difference in hydrolysis rate between the 2- and 4-isomers of no-carrier-added (~(18)F)fluoromethyl-L-phenylalanine
【24h】

Mechanistic approach of the difference in hydrolysis rate between the 2- and 4-isomers of no-carrier-added (~(18)F)fluoromethyl-L-phenylalanine

机译：无载载（〜（18）f）氟甲基-1-苯丙氨酸的2-和4-异构体与4-异构体之间水解速率差异的机械方法

获取原文
获取原文并翻译 | 示例
           
页面导航
  • 摘要
  • 著录项
  • 相似文献
  • 相关主题

摘要

No-carrier-added (n.c.a.) 2-[~(18)F]fluoromethyl-l-phenylaianine (2-[~(18)F]FMP) was found to be very sensitive to hydrolysis in aqueous solutions. In this paper, the defluorination reaction was studied in detail to elucidate its mechanism. Therefore, besides 2-[~(18)F]FMP and 4-[~(18)F]FMP, 2-[~(18)F]fluoromethyl-phenethylamine (2-[~(18)F]FMPAM) and 4-[~(18)F]FMPAM were synthesized, both 'mimetic' molecules of the decarboxylated amino acid analogues. Radiosynthesis, using a customized Scintomics automatic synthesis hotbox~(three) module, resulted in a high overall yield and a radiochemical purity of >99%. The defluorination rates of all compounds were studied by HPLC. The defluorination rate of 2-[~(18)F]FMLP at 50degC was approximately 300 times faster than that of n.c.a. 4-[~(18)F]FMLP. The defluorination rate of 2-[~(18)F]FMPAM is somewhat lower than of 2-[~(18)F]FMP but still very high in comparison with 4-[~(18)F]FMPAM, which is virtually stable. It allowed to elucidate the reaction mechanism ruled by two distinct intramolecular interactions. First, the hydrogen bond interaction between the amine and the benzylic fluorine weakening the carbon-fluorine bond. Secondly, the formation of a second hydrogen bond between the carboxyl oxygen atom and one of the benzylic hydrogen atoms rendering the benzyl fluoride group even more susceptible to hydrolysis.
机译：未载载（N.C.A.）2- [〜（18）F]氟甲基-1-苯基（2- [〜（18）F] FMP）对水溶液中的水解非常敏感。在本文中，详细研究了偏氟反应，以阐明其机制。因此，除了2- [〜（18）f] FMP和4- [〜（18）F] FMP，2- [〜（18）F]氟甲基 - 苯乙胺（2- [〜（18）F] FMPAM）和合成4- [〜（18）F] FMPAM，脱羧的氨基酸类似物的“模拟物”分子。可辐射合成，使用定制的Scintomics自动合成热箱〜（三）模块，总收率高，放射化学纯度> 99％。通过HPLC研究了所有化合物的偏氟速率。 50DEGC的2- [〜（18）F] FMLP的偏氟率比N.C.A的速度快约为300倍。 4- [〜（18）f] fmlp。 2- [〜（18）F] FMPAM的偏氟率略低于2- [〜（18）F] FMP，但与4- [〜（18）F] FMPAM相比，仍然非常高，这几乎是稳定的。它允许阐明通过两个不同的分子内相互作用统治的反应机制。首先，胺与苄基氟之间的氢键相互作用削弱了碳氟键。其次，在羧基氧原子和苄基氢原子之一之间形成第二氢键，使苄基氟基团甚至更易于水解。

著录项

相似文献

  • 外文文献
  • 中文文献
  • 专利
获取原文

客服邮箱：kefu@zhangqiaokeyan.com

京公网安备：11010802029741号 ICP备案号：京ICP备15016152号-6 六维联合信息科技 (北京) 有限公司©版权所有

  • 客服微信

  • 服务号