Synthesis of a [F]F Estradiol Derivative via Click Chemistry Using an Automated Synthesis Module: In Vitro Evaluation as Potential Radiopharmaceutical for Breast Cancer Imaging.

"Click reactions" are a very useful tool for the selective conjugation of different molecular subunits to produce complex structures in a simple way. In this paper, we present the application of Cu(I)-catalyzed biorthogonal reactions between alkynes and azides to the indirect radiofluorination of an estradiol derivative with potential applications in estrogen receptor imaging. The procedure was fully developed on an automated synthesis platform, and conditions were optimized to achieve the desired product with a reasonable yield without precipitation.

Radiosynthesis and validation of [ F]fluoroestradiol in a Synthra plus research platform for use in routine clinical practice.

In this practitioner protocol, the optimization of the radiochemical synthesis of [ F]fluoroestradiol (FES) on the Synthra RNplus research automated platform is described in detail and a quality control (QC) summary of three validation productions is presented. In comparison with published synthesis methods developed on other platforms, the yield was considerably improved (40%-45% ndc). The other important improvement is the reduction of the required concentration of H SO avoiding the production of high concentrations of acidic vapors that can deteriorate the module.