Thursday, March 4, 2021

Sulfur [18F]Fluoride Exchange Click Chemistry Enabled Ultrafast Late-Stage Radiosynthesis


Qinheng Zheng, Hongtao Xu, Hua Wang, Wen-Ge Han Du, Nan Wang, Huan Xiong, Yuang Gu, Louis Noodleman, K. Barry Sharpless, Guang Yang, and Peng Wu
Journal of the American Chemical Society 2021

DOI: 10.1021/jacs.0c09306

The lack of efficient [18F]fluorination processes and target-specific organofluorine chemotypes remains the major challenge of fluorine-18 positron emission tomography (PET). We report here an ultrafast isotopic exchange method for the radiosynthesis of novel PET agent aryl [18F]fluorosulfate enabled by the emerging sulfur fluoride exchange (SuFEx) click chemistry. The method has been applied to the fully automated 18F-radiolabeling of 25 structurally and functionally diverse aryl fluorosulfates with excellent radiochemical yield (83–100%, median 98%) and high molar activity (280 GBq μmol–1) at room temperature in 30 s. The purification of radiotracers requires no time-consuming HPLC but rather a simple cartridge filtration. We further demonstrate the imaging application of a rationally designed poly(ADP-ribose) polymerase 1 (PARP1)-targeting aryl [18F]fluorosulfate by probing subcutaneous tumors in vivo.

Oncogenic KRAS G12C: Kinetic and Redox Characterization of Covalent Inhibition

Minh V. Huynh, Derek Parsonage, Tom E. Forshaw, Venkat R. Chirasani, G. Aaron Hobbs, Hanzhi Wu, Jingyun Lee, Cristina M. Furdui, Leslie B. P...