CN(C)C(=O)[C@]1(C)C[C@H]1[C@H](NC(=O)CNC(=O)[C@@H]1CCCN1C(=O)[C@]1(C)C[C@H]1[C@H](NC(=O)OCc1ccccc1)c1ccccc1)c1ccccc1
A higher negative pKa value denotes a less powerful acid. What is this molecule's negative pKa value?