CCC(C)NC(=O)CSC1=Nc2ccccc2C2=NC(CC(=O)NCc3ccccc3)C(=O)N12
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?