CCOC(=O)c1[nH]c(C)c(CCC(=O)N2CCN(c3cc(Cl)ccc3C)CC2)c1C
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?