This small molecule is an inducer of apoptosis of tumor cells at a concentration of approximately 30− 100 nM.   It is a multi-kinase inhibitor with potent inhibitory activity against the CDK4/CYCLIN D1 and ARK5 kinases.

Systematic Name: 8-cyclopentyl-2-((4-(4-methylpiperazin-1-yl)phenyl)amino)-7-oxo-7,8-dihydropyrido[2,3-d]pyrimidine-6-carbonitrile

SMILES: CN1CCN(C2=CC=C(NC3=NC=C4C(N(C5CCCC5)C(C(C#N)=C4)=O)=N3)C=C2)CC1

Formula: C24H27N7O

Mol. Wt.: 429.53

Reference: Reddy, MV Ramana, et al. "Discovery of 8-cyclopentyl-2-[4-(4-methyl-piperazin-1-yl)-phenylamino]-7-oxo-7, 8-dihydro-pyrido [2, 3-d] pyrimidine-6-carbonitrile (7x) as a potent inhibitor of cyclin-dependent kinase 4 (CDK4) and AMPK-related kinase 5 (ARK5)." Journal of medicinal chemistry 57.3 (2014): 578-599.