N#Cc1ccc(NC(=O)N2CCC(c3nc(O)c4nnn(Cc5cccc(Cl)c5)c4n3)CC2)cc1
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?