SMILES: C[C@]1(C2=C(C(=CC=C2)O)C(=O)C3=C1[C@@H]([C@H]4[C@@H](C(=O)C(=C([C@]4(C3=O)O)[O-])C(=O)N)[NH+](C)C)O)O
Description: The molecule is a zwitterion obtained by transfer of a proton from the 2-hydroxy group to the adjacent tertiary amino group of 5a,11a-dehydrooxytetracycline; major species at pH 7.3. It is a tautomer of a 5a,11a-dehydrooxytetracycline.