COC(=O)C1C(=O)C2=C3N4C(C=C5C(C=C)=C(C)C6=[N]5[Mg]44N5C(=CC7=[N]4C(C(CCC(O)=O)=C7C)=C13)C(C)=C(C=C)C5=C6)=C2C