Abstract: Compounds are provided for reducing erythemal response which are photoreactive precursors to para-aminobenzoic acid or its physiologically acceptable esters. Upon exposure to ultraviolet radiation of greater than about 280nm, the compounds of this invention undergo a photoreactive degradation to provide a regulated amount of a sunscreen material which screens out ultraviolet radiation which could lead to erythema.The compounds are benzyl esters of p-carboxycarbanilic acid and the dermatological and physiological acceptable esters of the carboxy group.

Abstract: Compounds are provided for use in assays of organic compounds, where organic compounds of biological interest are determined at extremely low concentrations by combining in a medium, the composition to be determined, hereinafter referred to as ligand, a high molecular weight material of at least 10,000 molecular weight, which has a site spatially characterisitc of the ligand, hereinafter referred to as receptor, and an analog of the ligand having a free radical functionality hereinafter referred to as "ligand analog". The ligand analog and ligand in the medium compete for the receptor site, the amount of ligand analog bound to the receptor, being dependent on the amount of ligand present in the medium. By following the change in electron spin resonance spectrum of the ligand analog and comparing it to the change in spectrum which would be obtained in the absence of any ligand, the amount of ligand can be determined.

Abstract: Heterocyclic diazadioxides, having the two nitrogen atoms as annular atoms, are employed as quenchers for molecules in the excited state. The compounds can be used in combination with polymers and pigments for protection against light and oxidative attack. The products are also found to be efficient free radical inhibitors. Heterocyclic mono- and polycyclic diazadioxides are provided. All of the compounds are found to have relatively low triplet energy values.

Abstract: A novel immunoassay is provided, as well as particular reagents, for determining the presence of a ligand. A Reagent is employed having at least two epitopes, one of the epitopes being common with the ligand, and the other epitopes being foreign to the ligand. The two epitopes are positioned in the Reagent so that antibody bound to one of the epitopes sterically inhibits the binding of antibody to the second epitope.In carrying out the assay, the sample, the Reagent, and antibodies to the two epitopes are combined. Because of the steric inhibition to the simultaneous binding of the two antibodies to the Reagent, the amount of antibody bound to the epitope of the Reagent foreign to the ligand will be related to the amount of ligand present in the assay medium. By analyzing directly or indirectly for the antibody bound to the epitope foreign to the ligand, and comparing the results to known standards, qualitative or quantitative determinations of the amount of ligand may be made.