CC1=CC(=O)C(C2=C(O)C(=O)C(C)=CC2=O)=C(O)C1=O    mol11933    0_1
CC1=CC(=O)C(C2=C(O)C(=O)C(C)=CC2=O)=C([O-])C1=O    mol11933    -1_1
CC1=CC(=O)C(C2=C([O-])C(=O)C(C)=CC2=O)=C([O-])C1=O    mol11933    -2_1