COc1cc(-c2ccc3c(c2)Nc2ccc(CCOc4ccc(N5CCOCC5)cc4)cc2NC3=O)ccc1OCC(O)CO
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?