General synthetic methods have been devised to prep. derivatized mixed-​ring heterocyclic and antenna carotene ligands with nitrogen donor atoms. Synthetic methods involve prepn. of intermediate compds. in route to arom. heterocyclic products with bidentate and monodentate coordination sites. Coupling reactions resulted in formation of the mixed-​ring heterocycles whereas condensation reactions of carotene aldehydes with org. mols. lacking beta hydrogen atoms formed ligands with either pyridine and​/or cyanide linkages. Further, condensation reactions have been used to prep. uracil​/multidentate ligand motifs. The ligands were characterized by elemental analyses, NMR and single x-​ray diffraction methods. These ligands are being used to prep. organometallic complexes for solar energy and therapeutic purposes.