CCOc1ccc(/C=C/C(O)=C2\C(=O)NC3(C)CC2c2ccccc2O3)cc1OC
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?