O=C(CCCn1c(=S)[nH]c2cc3c(cc2c1=O)OCO3)N1CCN(c2ccccc2F)CC1
The negative base-10 logarithmic of dissociation constant (pka) for an acid is a direct consequence of the underlying thermodynamics of the dissociation reaction; the pKa value is directly proportional to the standard Gibbs free energy change for the reaction. What is the pka value of this molecule?