COc1cccc(C(c2sc3nc(-c4ccco4)nn3c2O)N2CCC3(CC2)OCCO3)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?