Br.CN(C)CCCSc1c2ccccc2nc2cc(NCC(=O)Nc3ccccc3-c3ccccc3NC(=O)CNc3ccc4c(SCCCN(C)C)c5ccccc5nc4c3)ccc12
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?