Recent methods for the synthesis of fused pyrazolo[3,4(4,3)-d]thiazoles and pyrazolo[3,4(4,3)-d][1,4]thiazines (microreview)

This microreview discusses the latest examples (2012–2022) of the synthesis of pyrazolo[3,4-d]-thiazoles, pyrazolo[4,3-d]thiazoles, pyrazolo[4,3-b][1,4]thiazines, and pyrazolo[3,4-b][1,4]-thiazines via two main approaches: annulation of the pyrazole ring to the thiazole or thiazine ring and, conversely, annulation of the thiazole or thiazine ring to the pyrazole ring.