Copper‐Assisted Synthesis of Novel Pyrazolo[3,4‐ d ]thiazoles

Based on both the chemical and the biological importance of the pyrazole and the thiazole backbones, we report herein a convenient design of new pyrazolo[3,4‐ d ]thiazoles for the development of molecules with a high therapeutic potential. The effective and appropriate strategy chosen consists of an intramolecular copper‐catalysed N ‐arylation followed by the Liebeskind‐Srogl cross‐coupling reaction. The efficiency of copper and palladium catalysts for the first step of the synthesis was evaluated. These efforts allowed the synthesis of a variety of modulated heterobicycles.