CC(=O)N(C)CC(=O)O    mol13518    0_1
CC(=O)N(C)CC(O)=[OH+]    mol13518    1_1
CC(=[OH+])N(C)CC(=O)O    mol13518    1_2
CC(=O)N(C)CC(=O)[O-]    mol13518    -1_1