COc1ccc2nc3c(O)n(/N=C/c4ccc(OC)c(CN5CCCC5)c4)c(C)nc-3c2c1
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?