CN1C(C(=O)Nc2ccc(F)cc2F)=CC(c2ccc3c(c2)OCO3)=NS1(=O)=O
An acid's negative base-10 logarithmic dissociation constant (pka) follows directly from its underlying thermodynamics; pKa is directly proportional to its standard Gibbs free energy change. What is the pka value of this molecule?