Brc1ccc2c(-c3csc(-c4c[nH]c5ccc(Br)cc45)n3)c[nH]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?