Improved synthesis of the bifunctional chelator p-SCN-Bn-HOPO.

  title={Improved synthesis of the bifunctional chelator p-SCN-Bn-HOPO.},
  author={N. V. S. Dinesh K. Bhupathiraju and Ali Younes and Minhua Cao and Jafar Sunga Ali and Huseyin T. Cicek and Kathryn M Tully and Shashikanth Ponnala and John W. Babich and Melissa A Deri and Jason S. Lewis and Lynn C. Francesconi and Charles Michael Drain},
  journal={Organic \& biomolecular chemistry},
The bifunctional ligand p-SCN-Bn-HOPO, which has four 1,2-hydroxypyridinone groups on a spermine backbone with an isothiocyanate linker, has been shown to be an efficient and stable chelator for Zr(iv) and, more importantly, the radioisotope 89Zr for use in radiolabeling antibodies for positron emission tomography (PET) imaging. Previous studies of 89Zr-HOPO-trastuzumab in mice showed low background, good tumor to organ contrast, and very low bone uptake which show p-SCN-Bn-HOPO to be an… 

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Macrocycle-Based Hydroxamate Ligands for Complexation and Immunoconjugation of 89Zirconium for Positron Emission Tomography (PET) Imaging.

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A bifunctional isothiocyanate variant of the octadentate chelator DFO* is reported, a candidate successor of DFO for future clinical 89Zr-immuno-PET studies and shows superior in vitro stability and in vivo performance when compared to 89 Zr-DFO-trastuzumab.

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