COc1cc(C2C(C(=O)Nc3cc(F)c(F)cc3F)=C(C)NC(C)=C2C(=O)Nc2cc(F)c(F)cc2F)ccc1O
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?