COc1ccc(OC)c(C(C(=O)NC2CCCCC2)N(C(=O)c2snc(C(N)=O)c2N)c2ccccc2OC)c1
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?