COc1ccc(-n2c3c(c4cc(O)ccc42)C(=O)c2ccccc2C3=O)cc1
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?