CCC(=O)Nc1cccc(C2=NOC3(C2)C[C@H](C(N)=O)N(C(=O)c2ccccc2)C3)c1
The negative base-10 logarithmic of dissociation constant (pka) for an acid is a direct consequence of the underlying thermodynamics of the dissociation reaction; the pKa value is directly proportional to the standard Gibbs free energy change for the reaction. What is the pka value of this molecule?