CN(Cc1c(C(=O)N/N=C/c2ccccc2O)nnn1-c1nonc1N)C1CCCCC1
An acid's negative base-10 logarithmic dissociation constant (pka) follows directly from its underlying thermodynamics; pKa is directly proportional to its standard Gibbs free energy change. What is the pka value of this molecule?