O=C(/C=C/c1ccc(Br)cc1)NC(=S)N1C[C@H]2C[C@H](C1)c1cccc(=O)n1C2
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?