CCOCCCn1c(SCC(=O)Nc2ccc(C(C)C)cc2)nc2c(sc3ccccc32)c1=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?