Synthesis And Pharmacological Activities Of Pyrazolo[3,4-d]Pyrimidine Derivatives Containing 1,3,4-Thiadiazole

Pyrazolo[3, 4-d]pyrimidines have drawn considerable attention on the account of their structural similarity with purines and pharmacological importance. 1,3,4-Thiadiazoles are a kind of N-containing heterocylic compounds with important bioactivities. Fluorinated compounds are one of the research hotspots in modern medicinal and agrochemistry chemistry. By retrieving concerned literatures, the recent research progress of pyrazolo[3, 4-d]pyrimidine derivatives, 1,3,4-thiadiazole derivatives and fluorinated compounds were reviewed.With aim of searching for novel highly pharmacological compounds, we have modified the main structure of pyrazolo[3, 4-d]pyrimidines and synthesized 30 new pyrazolo[3,4-d]pyrimidine derivatives containing 1,3,4-thiadiazole by Bioisosterism and Superposition Principles. The structures of all the title compounds were comfirmed by IR, MS, 1H NMR and elementary analysis. Also, their physical- chemical properties, spectral properties and reaction conditions were discussed. The preliminary test in vitro indicated that some of title compounds Ia-j exhibit good anticancer activity against HL-60, especially If and Ij exhibit even higher activity than Doxorubicin (DOX). While, some of the compounds IIa-l and IIIa-h show a certain degree of antibacterial activity only against Staphylococcus aureus.The structural formulas of the title compounds are given below:(I) 5-(5-Substituted-1,3,4-thiadiazole-2-yl)-1-phenyl/H-pyrazolo[3, 4-d]pyrimid- ine-4(5H)-imine(?)(II) N-[5-(Substituted benzylthio)-1,3,4-thiadiazole-2-yl]-1-phenyl-1H-pyrazolo [3, 4-d]pyrimidine-4-amine (?) (III) 1-Phenyl-4-(5-substituted-1,3,4-thiadiazol-2-ylthio)-6-(trifluoromethyl)-1H- pyrazolo[3, 4-d]pyrimidine (?)...