CCOC(=O)C(=O)CC(=O)C1=C(c2ccccc2OC)CC(c2cccs2)=CC1=O
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?