A member of the class of aminopyrimidines that is 2-aminopyrimidine substituted at positions N2, 5 and 6 by (5-cyanopyridin-2-yl)ethyl, 4-methylimidazol-2-yl and 2,4-dichlorophenyl groups respectively. ChEBI: CHIR 99021 is a member of the class of aminopyrimidines that is 2-aminopyrimidine substituted at positions N2, 5 and 6 by (5-cyanopyridin-2-yl)ethyl, 4-methylimidazol-2-yl and 2,4-dichlorophenyl groups respectively. It has a role as an EC 2.7.11.26 (tau-protein kinase) inhibitor. It is a member of imidazoles, a dichlorobenzene, an aminopyrimidine, an aminopyridine, a cyanopyridine, a secondary amino compound and a diamine.