CCOC(=O)N1CCN(C(c2ccc(C(C)C)cc2)c2sc3nc(C)nn3c2O)CC1
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?