COC(=O)c1sc(N2C(=O)c3oc4ccc(C)cc4c(=O)c3C2c2ccc(O)c(OC)c2)nc1C
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?