CC(Nc1nc(-c2cccc(Br)c2)cs1)c1nc2cc(Cl)c(N3CCCCC3)cc2n1CCOCCO
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?