O=C(CSc1cn(CCNC(=O)c2c(F)cccc2F)c2ccccc12)Nc1ccc2c(c1)OCCO2
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?