作者:Chih-Hao K. Kao、Mark B. Sassaman、Lawrence P. Szajek、Ying Ma、Atsuo Waki、William C. Eckelman
DOI:10.1002/jlcr.515
日期:2001.11
Thymidine analogs labeled with positron emitting radionuclides are potential proliferation markers for positron emission tomography (PET). Bromine-76 (T1/2=16.2 h) is our choice of radionuclide, because it allows for maximal DNA incorporation of the tracer. Following the literature descriptions, 76Br was produced using the 75As (3He, 2n) 76Br reaction. We then recovered 76Br from the target in the form of [76Br]NH4Br with a yield of 60±12% (n=32). Peracetic acid was used as the oxidant for electrophilic bromodestannylation to prepare [76Br]FBAU 3′,5′-dibenzoate (71.2±12.1%, RCY) and a basic hydrolysis of the dibenzoate then yielded [76Br]FBAU. The yield of the hydrolysis reaction was 53.1±9.2% when heated at 100°C for 15 min or quantitative (decay corrected) when left at room temperature overnight. The sequential synthesis of [76Br]FBAU 3′,5′-dibenzoate and [76Br]FBAU allowed us to perform a side-by-side comparison of their metabolic stabilities. While [76Br]FBAU 3′,5′-dibenzoate was hydrolyzed to [76Br]FBAU within 10 minutes by hepatocyte at 37°C, [76Br]FBAU was stable and no [76Br]Br− was released from either radiopharmaceutical. Both compounds are potential proliferation markers for PET. Copyright © 2001 John Wiley & Sons, Ltd.
用正电子发射放射性核素标记的胸苷类似物是正电子发射断层扫描(PET)的潜在增殖标记物。溴-76(T1/2=16.2 小时)是我们选择的放射性核素,因为它能使示踪剂最大程度地与 DNA 结合。根据文献描述,我们利用 75As (3He, 2n) 76Br 反应生成了 76Br。然后,我们以[76Br]NH4Br 的形式从目标物中回收了 76Br,回收率为 60±12%(n=32)。以过氧乙酸为氧化剂进行亲电溴烷基化反应,制备出[76Br]FBAU 3′,5′-二苯甲酸酯(71.2±12.1%,RCY),然后对二苯甲酸酯进行碱性水解,得到[76Br]FBAU。水解反应的收率在 100°C 下加热 15 分钟时为 53.1±9.2%,在室温下放置过夜时为定量(衰减校正)。通过依次合成[76Br]FBAU 3′,5′-二苯甲酸酯和[76Br]FBAU,我们可以并排比较它们的代谢稳定性。在 37°C 温度下,[76Br]FBAU 3′,5′-二苯甲酸酯在 10 分钟内被肝细胞水解为[76Br]FBAU,而[76Br]FBAU 则很稳定,两种放射性药物都没有释放出[76Br]Br-。这两种化合物都是 PET 潜在的增殖标记物。Copyright © 2001 John Wiley & Sons, Ltd. All Rights Reserved.