C[C@H]1CCCCO[C@H](CN(C)C(=O)Nc2ccc(F)cc2)[C@@H](C)CN([C@@H](C)CO)C(=O)c2cc(NC(=O)Nc3ccc4c(c3)OCO4)ccc2O1
A lower number of pka indicates that the acid dissociates more entirely in water. What is pka of the molecule?