COc1ccc(CCNS(=O)(=O)c2c(C)[nH]c(C)c2C(=O)N2CCCCC2)cc1OC
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?