pka_value	data_source	charge_state_pre	charge_state_post	microspecies_pre	microspecies_post	molid	smiles
1.48	IUPAC digitized pKa	0	-1	O=C(O)C[N+](=O)[O-]	O=C([O-])C[N+](=O)[O-]	mol1774	O=C(O)C[N+](=O)[O-]
1.63	Datawarrior	0	-1	O=C(O)C[N+](=O)[O-]	O=C([O-])C[N+](=O)[O-]	mol1774	O=C(O)C[N+](=O)[O-]
1.68	OCHEM	0	-1	O=C(O)C[N+](=O)[O-]	O=C([O-])C[N+](=O)[O-]	mol1774	O=C(O)C[N+](=O)[O-]
1.62999999523163	QSARToolbox	0	-1	O=C(O)C[N+](=O)[O-]	O=C([O-])C[N+](=O)[O-]	mol1774	O=C(O)C[N+](=O)[O-]
1.48000001907349	QSARToolbox	0	-1	O=C(O)C[N+](=O)[O-]	O=C([O-])C[N+](=O)[O-]	mol1774	O=C(O)C[N+](=O)[O-]
1.67999994754791	QSARToolbox	0	-1	O=C(O)C[N+](=O)[O-]	O=C([O-])C[N+](=O)[O-]	mol1774	O=C(O)C[N+](=O)[O-]
8.9	IUPAC digitized pKa	-1	-2	O=C([O-])C[N+](=O)[O-]	O=C([O-])[CH-][N+](=O)[O-]	mol1774	O=C(O)C[N+](=O)[O-]