Cc1ccc2cc(C3C(C#N)=C(N)Oc4c3ccc3cccnc43)c(O)nc2c1
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?