CCCCN(CC)CCCN=C(S)Nc1ccc2nc(N3CCN(C)CC3)cc(C)c2c1
An acid's negative base-10 logarithmic dissociation constant (pKa) follows directly from its underlying thermodynamics; the negative pKa is directly proportional to its standard Gibbs free energy change. What is the negative pKa value of this molecule?