Abstract: Novel symmetrical and asymmetrical 10,10′-substituted-9,9′-biacridines and the synthesis of such symmetrical and asymmetrical 10,10′-substituted-9,9′-biacridine molecules and their derivatives is disclosed. These molecules are shown to produce light by chemiluminescence in the presence of signal solutions. These symmetrical or asymmetrical 10,10′-substituted-9,9′-biacridines are used alone or attached to haptens or macromolecules and are utilized as labels in the preparation of chemiluminescent, homogeneous or heterogeneous assays. They are also used in conjunction with other chemiluminescent label molecules to produce multiple analyte chemiluminescent assays.