Application and SARs of Pyrazolo[1,5-a]pyrimidine as Antitumor Agents Scaffold.

Pyrazolo[1,5-a]pyrimidines are fused heterocycles that have spawned many biologically active antitumor drugs and are important privileged structures for drug development. Pyrazolo[1,5- a]pyrimidine derivatives have played an important role in the development of antitumor agents due to their structural diversity and good kinase inhibitory activity. In addition to their applications in traditional drug targets such as B-Raf, KDR, Lck, and Src kinase, some small molecule drugs with excellent activity against other kinases (Aurora, Trk, PI3K-γ, FLT-3, C-Met kinases, STING, TRPC) have emerged in recent years. Therefore, based on these antitumor drug targets, small molecule inhibitors containing pyrazolo[1,5-a]pyrimidine scaffold and their structure-activity relationships are summarized and discussed to provide more reference value for the application of this particular structure in antitumor drugs.