O=C(NCC(=O)N(CC1CCCO1)C(C(=O)NC1CCCCC1)c1ccc(F)cc1)c1ccco1
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?