pka_value	data_source	charge_state_pre	charge_state_post	microspecies_pre	microspecies_post	molid	smiles
2.8	IUPAC digitized pKa	0	-1	O=C(O)c1nnc(C(=O)O)nn1	O=C([O-])c1nnc(C(=O)O)nn1	mol9143	O=C(O)c1nnc(C(=O)O)nn1