COc1ccc2c(c1)C(C)CC(C)(C)N2C(=O)CSc1nc[nH]n1
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?