COc1ccc2c(c1OC)C(=O)N1C2SC(C)(C)[C@H]1C(=O)NCC(C)C
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?