One-pot synthesis and antiproliferative evaluation of pyrazolo[3,4-d]pyrimidine derivatives

An efficient one-pot methodology for the synthesis of pyrazolo[3,4-d]pyrimidines was developed by using 5-aminopyrazoles with formamide in presence of PBr3 as the coupling agent. Among the examples presented in this work, compounds 41 and 54–56 with phenyl or 2-quinolinyl groups at N-1 and p-Me–Ph, p-Cl–Ph, or p-OMe–Ph group at C-3 position in the pyrazole ring possessed better potency against NCI-H226 and NPC-TW01 cancer cells with GI50 values between 18 μM and 39 μM.