Synthesis and evaluation of an (125)I-labeled azide prosthetic group for efficient and bioorthogonal radiolabeling of cyclooctyne-group containing molecules using copper-free click reaction

  • Bioorg Med Chem Lett. 2016 Feb 1;26(3):875-878. doi: 10.1016/j.bmcl.2015.12.073.
Mi Hee Choi  1 ,  Ha Eun Shim  1 ,  You Ree Nam  1 ,  Hye Rim Kim  1 ,  Jung Ae Kang  1 ,  Dong-Eun Lee  1 ,  Sang Hyun Park  2 ,  Dae Seong Choi  1 ,  Beom-Su Jang  3 ,  Jongho Jeon  4
Affiliations
  • 1. Advanced Radiation Technology Institute, Korea Atomic Energy Research Institute, Jeongeup, Jeonbuk 580-185, Republic of Korea.
  • 2. Advanced Radiation Technology Institute, Korea Atomic Energy Research Institute, Jeongeup, Jeonbuk 580-185, Republic of Korea; Department of Radiation Biotechnology and Applied Radioisotope Science, Korea University of Science and Technology, Daejeon 305-350, Republic of Korea.
  • 3. Advanced Radiation Technology Institute, Korea Atomic Energy Research Institute, Jeongeup, Jeonbuk 580-185, Republic of Korea; Department of Radiation Biotechnology and Applied Radioisotope Science, Korea University of Science and Technology, Daejeon 305-350, Republic of Korea. Electronic address: [email protected].
  • 4. Advanced Radiation Technology Institute, Korea Atomic Energy Research Institute, Jeongeup, Jeonbuk 580-185, Republic of Korea; Department of Radiation Biotechnology and Applied Radioisotope Science, Korea University of Science and Technology, Daejeon 305-350, Republic of Korea. Electronic address: [email protected].
PMID: 26748695 DOI: 10.1016/j.bmcl.2015.12.073
Abstract

Herein we report the radiosynthesis of a pyridine derived azide prosthetic group for iodine radioisotope labeling of dibenzocyclooctyne (DBCO) conjugated molecules. The radiolabeling of the stannylated precursor 2 was conducted using [(125)I]NaI and chloramine-T to give (125)I-labeled azide ([(125)I]1) with high radiochemical yield (72±8%, n=4) and radiochemical purity (>99%). Using (125)I-labeled azide ([(125)I]1), cyclic RGD peptide and near infrared fluorescent molecule were efficiently labeled with modest to good radiochemical yields. The biodistribution study and SPECT/CT images showed that [(125)I]1 underwent rapid renal clearance. These results clearly demonstrated that [(125)I]1 could be used as an useful radiotracer for in vivo pre-targeted imaging as well as efficient in vitro radiolabeling of DBCO containing molecules.

Keywords
Biodistribution; Copper-free click reaction; In vivo imaging; Iodine radioisotope; Radiolabeling.
Products