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Positron emission tomography (PET) imaging of Colony Stimulating Factor 1 Receptor (CSF1R) is a new strategy for quantifying both neuroinflammation and inflammation in the periphery since CSF1R is expressed on microglia and macrophages. AZ683 has high affinity for CSF1R (K<i>_i</i> = 8 nM; IC₅₀ = 6 nM) and &gt;250-fold selectivity over 95 other kinases. In this paper, we report the radiosynthesis of [¹¹C]AZ683 and initial evaluation of its use in CSF1R PET. [¹¹C]AZ683 was synthesized by ¹¹C-methylation of the desmethyl precursor with [¹¹C]MeOTf in 3.0% non-corrected activity yield (based upon [¹¹C]MeOTf), &gt;99% radiochemical purity and high molar activity. Preliminary PET imaging with [¹¹C]AZ683 revealed low brain uptake in rodents and nonhuman primates, suggesting that imaging neuroinflammation could be challenging but that the radiopharmaceutical could still be useful for peripheral imaging of inflammation.