[{"from": "human", "value": "Could you provide a description of this molecule? [C][C][Branch1][C][C][N][C][C][N][Branch1][Branch1][C][C][Ring1][=Branch1][C][=C][N][=C][Branch1][Branch1][C][=C][Ring1][=Branch1][N][C][=N][C][=C][C][=C][C][=Branch1][C][=O][N][C][C][Branch1][#Branch2][N][Ring1][#Branch1][C][Ring1][#Branch2][=N][Ring1][=C][C][C][C][C][C][Ring1][=Branch2]"}, {"from": "gpt", "value": "The molecule is an orally bioavailable inhibitor of cyclin-dependent kinase (CDK) types 4 (CDK4) and 6 (CDK6), with potential antineoplastic activity. Upon administration, lerociclib selectively inhibits CDK4 and CDK6, which inhibits the phosphorylation of retinoblastoma protein (Rb) early in the G1 phase, prevents CDK-mediated G1-S phase transition and leads to cell cycle arrest. This suppresses DNA replication and decreases tumor cell proliferation. CDK4 and 6 are serine/threonine kinases that are upregulated in many tumor cell types and play a key role in the regulation of both cell cycle progression from the G1-phase into the S-phase and tumor cell proliferation."}]