COc1ccc2c3c1OC1c4[nH]c5ccccc5c4CC4(O)C(C2)N(C)CCC314
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?