O=C(OC(c1ccccc1)c1ccccc1)[C@@H]1[C@@H]2C(=O)N(c3cccc(F)c3)C(=O)[C@@H]2[C@H]2C=Cc3ccccc3N12
A lower number of negative pKa indicates that the acid dissociates more entirely in water. What is the negative pKa of this molecule?