O=C(N/N=C1/C[C@@H](O)[C@@H](O)[C@H]2[C@H]1CC[C@H]1C(=O)N(c3ccc(F)cc3F)C(=O)[C@H]21)OCc1ccccc1
A lower number of pka indicates that the acid dissociates more entirely in water. What is pka of the molecule?