Cc1cccc(N2CCN(C(=O)c3c4c(nc5ccccc35)C(=O)N(C3CCCCC3)C4)CC2)c1C
An acid's negative base-10 logarithmic dissociation constant (pka) follows directly from its underlying thermodynamics; pKa is directly proportional to its standard Gibbs free energy change. What is the pka value of this molecule?