CC1=C(C(=O)Nc2ccccc2C)C(c2ccncc2)n2nc(SCc3ccccc3)nc2N1
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?