CNC(=O)c1sc(N2N=C3/C(=C/c4ccccc4)CCCC3C2c2ccccc2)nc1C
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?