Syntheses of N-3(substituted) analogues of thymidine, N-3([18F]fluorobutyl)thymidine ([18F]-FBT) and N-3([18F]fluoropentyl)thymidine ([18F]-FPT) are reported. 1,4-Butane diol and 1,5 pentane diol were converted to their tosyl derivatives 2 and 3 followed by conversion to benzoate esters 4 and 5, respectively. Protected thymidine 1 was coupled separately with 4 and 5 to produce 6 and 7, which were hydrolyzed to 8 and 9, then converted to their mesylates 10 and 11, respectively. Compounds 10 and 11 were fluorinated with n-Bu4N[18F] to produce 12 and 13, which by acid hydrolysis yielded 14 and 15, respectively. The crude products were purified by HPLC to obtain [18F]-FBT and [18F]-FPT. The radiochemical yields were 58–65% decay corrected (d.c.) for 14 and 46–57% (d.c.) for 15 with an average of 56% in three runs per compound. Radiochemical purity was >99% and specific activity was >74 GBq/µmol at the end of synthesis (EOS). The synthesis time was 65–75 min from the end of bombardment (EOB). Copyright © 2006 John Wiley & Sons, Ltd.
报告了
胸苷的 N-3(取代)类似物 N-3([18F]
氟丁基)
胸苷([18F]-FBT)和 N-3([18F]
氟戊基)
胸苷([18F]-F
PT)的合成。
1,4-丁二醇和
1,5-戊二醇分别转化为其
甲苯基衍
生物 2 和 3,然后再转化为
苯甲酸酯 4 和 5。受保护的
胸苷 1 与 4 和 5 分别偶联生成 6 和 7,再
水解为 8 和 9,然后分别转化为它们的
甲磺酸盐 10 和 11。化合物 10 和 11 与 n-Bu4N[18F]
氟化后生成 12 和 13,酸
水解后分别生成 14 和 15。粗产物经 HPLC 纯化后得到 [18F]-FBT 和 [18F]-F
PT。经衰减校正(d.c.),14 的放射
化学收率为 58-65%,15 的放射
化学收率为 46-57%(d.c.),每个化合物三次运行的平均收率为 56%。合成结束时(EOS),放射性纯度大于 99%,比活度大于 74 GBq/µmol。从轰击结束(
EOB)算起,合成时间为 65-75 分钟。Copyright © 2006 John Wiley & Sons, Ltd. All Rights Reserved.