Palbociclib 7A Regio-Isomer Impurity

1941177-47-4

tert-Butyl (E)-4-(6-((6-(2-butoxyvinyl)-8-cyclopentyl-5-methyl-7-oxo-7,8-dihydropyrido[2,3-d]pyrimidin-2-yl)amino)pyridin-3-yl)piperazine-1-carboxylate; 1-Piperazinecarboxylic acid, 4-[6-[[6-[(1E)-2-butoxyethenyl]-8-cyclopentyl-7,8-dihydro-5-methyl-7-oxopyrido[2,3-d]pyrimidin-2-yl]amino]-3-pyridinyl]-, 1,1-dimethylethyl ester; 1,1-Dimethylethyl 4-[6-[[6-[(1E)-2-butoxyethenyl]-8-cyclopentyl-7,8-dihydro-5-methyl-7-oxopyrido[2,3-d]pyrimidin-2-yl]amino]-3-pyridinyl]-1-piperazinecarboxylate;