SMILES: C[C@@]1(C2=C(C(=O)C3=C1C=CC=C3O)C(=O)[C@]4([C@@H](C2)[C@@H](C(=O)C(=C4[O-])C(=O)N)[NH+](C)C)O)O
Description: The molecule is zwitterionic form of 12-dehydrotetracycline arising from transfer of a proton from the 2-hydroxy group to the adjacent tertiary amino group. It is a tautomer of a 12-dehydrotetracycline.