Advances in Pyrazolopyrimidine Scaffold: Synthetic Strategies and Biological Applications (2019-Present)

The pyrazolopyrimidines are a significant category of heterocyclic fused compounds that have gained growing interest owing to their wide range of biological functions as well as their synthetic all-purpose. The review draws attention to the current advances (2019-2025) in the synthesis, structural rearrangement, and pharmacological assessments of pyrazolopyrimidines with particular focus on pyrazolo[3,4-d]pyrimidine and pyrazolo[1,5-a]pyrimidine derivatives. The latter scaffolds have also been efficiently and sustainably approached through recent synthetic methodologies, such as multicomponent reactions, microwave-assisted synthesis, and green chemistry methodologies. Several derivatives have been shown to have strong anticancer, antimicrobial, anti-inflammatory, and antiviral effects, usually through the action on important enzymes, including CDK2, FLT3, VEGFR-2, PIM-1, and Topoisomerase IIa.