N-(2-Chloro-4-pyrimidinyl)-N,2,3-trimethyl-2H-indazol-6-amine is an impurity of Pazopanib (P210925), an oral angiogenesis inhibitor targeting VEGFR and PDGFR.
A flask was charged with N,2,3-trimethyl-2H-indazol-6-amine (1 eq.), 2,4-dichloropyrimidine (1.5 eq.), sodium bicarbonate (2 eq.) and N, N-dimethylformamide. The reaction mixture was stirred at 85 °C until completion of the reaction. Then, water was added and stirred for 3 h. Product crystals were collected by filtration, washed with water, and then dried to get N-(2-chloropyriMidin-4-yl)-N,2,3-triMethyl-2H-indazol-6-aMine as off-white/beige powder (Yield: 97%).
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