COc1cccc(N2CCN(Cc3nc(O)c4c(-c5ccccc5)csc4n3)CC2)c1
An acid's negative base-10 logarithmic dissociation constant (pKa) follows directly from its underlying thermodynamics; the negative pKa is directly proportional to its standard Gibbs free energy change. What is the negative pKa value of this molecule?