Design and synthesis of 4-alkynyl pyrazoles as inhibitors of PDE4: A practical access via Pd/C–Cu catalysis

The design and synthesis of 4-alkynyl pyrazole derivatives has led to the identification of new class of PDE4 inhibitors. All these compounds were accessed for the first time via a facile Pd/C–CuI–PPh3 mediated C–C bond forming reaction between an appropriate pyrazole iodide and various terminal alkynes. In vitro PDE4B inhibitory properties and molecular modeling studies of some of the compounds synthesized indicated that 4-alkynyl pyrazole could be a promising template for the discovery of novel PDE4 inhibitors.

Graphical abstractDesign, synthesis, PDE4 inhibitory properties along with docking studies of new 4-alkynyl pyrazoles is presented.Figure optionsDownload full-size imageDownload as PowerPoint slide