CCN1CC2=C(NC(=S)NC2c2cc(OC)c(OC)c(OC)c2)/C(=C/c2cc(OC)c(OC)c(OC)c2)C1
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?