COc1cccc(Nc2ncc3nc(-c4ccc(Cl)cc4)c(=O)n(C[C@H]4CCCO4)c3n2)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?