CC1=C(C=C)C2=CC3=[N+]4C(=CC5=C(C)C(CCC(O)=O)=C6N5[Fe]44N2C1=CC1=[N+]4C(C(CCC(O)=O)=C1C)=C6C1=CC=CC=C1)C(C=C)=C3C