CCOc1cccc(C2C(C(=O)c3ccc(C)o3)=C(O)C(=O)N2c2nccs2)c1
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?