Disclosed are substituted pyrazolo pyrimidine compounds of formula I, salts thereof, and methods for their preparation. Specific examples of compounds of formula I include: (4-methoxy-benzyl-[1-(3-ethynyl-phenyl)-1H-pyrazolo [3,4-d] pyrimidine-4yl)-amine, [1-(3-trimethylsilanyl ethynyl-phenyl)-1H-pyrazolo[3,4-d]pyrimidine-4yl)-(3,4,5-trimethoxybenzyl)-amine, and [4-(3-morpholin-4-yl-propoxy)-benzyl]-[1-(3-iodo-phenyl)-1H-pyrazolo[3,4-d]pyrimidine-4yl)-amine. Specifically disclosed is a synthetic method for N-((2,3-dihydrobenzo[b][1,4]dioxin-6-yl)methyl)-1-(3,5-dimethylphenyl)-1H-pyrazolo[3,4-d]pyrimidin-4-amine. Also disclosed is the use of a compound of formula I for treating lung cancer, squamous cell cancer, bladder cancer, gastric cancer, pancreatic cancer, breast cancer, head cancer, neck cancer, esophageal cancer, brain cancer, gynecological cancer, prostate cancer, kidney cancer, leukemia, lymphoma or thyroid cancer.
