Abstract
A practical, multigram approach to the 2-(2-(4-alkoxyphenyl)-5,7-dimethylpyrazolo[1,5-a]pyrimidin-3-yl)acetamide (DPA) class of ligands targeting the translocator protein (TSPO) is described. This synthetic route offers several improvements over all previously described sequences, including the isolation of intermediates without resort to chromatography. The common precursor to the DPA class of high affinity TSPO ligands, N,N-diethyl-2-(2-(4-hydroxyphenyl)-5,7-dimethylpyrazolo[1,5-a]pyrimidin-3-yl)acetamide, was produced in 40% yield over six steps, and was cleanly alkylated to give multigram quantities of several DPA analogues in 90–96% yield after recrystallization.
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have