6 - bromine - 8 - cyclopentyl - 5 - methyl - 2 - [[5 - (1 - piperazine) - 2 - pyridyl) amino] - [2, 3 - d] pyridine and pyrimidine - 7 (8 h) - ketone (pab impurity A)

4 - [6-8 - cyclopentyl - 7, 8 - [2-5 - methyl - 7 - hydrogen oxygen generation of pyridine and [2, 3 - d] pyrimidine - 2 - base) amino] - 3 - pyridyl] - 1 - piperazine E impurities (pab)