Question: Please provide a description of this drug's mechanism of action.
Constraint: The Chemical has the SMILES CNCc1ccc(-c2cc(-c3nc(-c4ccc(S(=O)(=O)C(C)C)cc4)cnc3N)on2)cc1.
Answer: Serine-protein kinase ATR inhibitor
{#Question|Q!}: {quest#}
{#Constraint:|Description:|!} The {#Molecule|Compound|Chemical!} {#has the|can be represented with the!} {SMILES__description} {SMILES#}.
{#Answer|Result|Answer!}: {answ#}
CNCc1ccc(-c2cc(-c3nc(-c4ccc(S(=O)(=O)C(C)C)cc4)cnc3N)on2)cc1
CNCc1ccc(-c2cc(-c3nc(-c4ccc(S(=O)(=O)C(C)C)cc4)cnc3N)on2)cc1
3-[3-[4-(methylaminomethyl)phenyl]-1,2-oxazol-5-yl]-5-(4-propan-2-ylsulfonylphenyl)pyrazin-2-amine
Please provide a description of this drug's mechanism of action.