CCOC(=O)CSc1[nH]c(NC(=S)Nc2ccccc2)c(C(N)=O)c1C(N)=O
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?