COc1ccc(NC(=O)Nc2nnc(N(CC(C)C)CC(C)C)s2)c(OC)c1
The negative base-10 logarithmic of dissociation constant (pka) for an acid is a direct consequence of the underlying thermodynamics of the dissociation reaction; the pKa value is directly proportional to the standard Gibbs free energy change for the reaction. What is the pka value of this molecule?