Cc1cnc(C(=O)[O-])c[nH+]1    mol9671    0_1
Cc1c[nH+]c(C(=O)[O-])cn1    mol9671    0_2
Cc1cnc(C(=O)O)cn1    mol9671    0_3
Cc1cnc(C(=O)[O-])cn1    mol9671    -1_1