Luminescence of Tautomeric Forms of Thymine Monoanions

The fluorescence and phosphorescence emission and excitation spectra of monoan‐ions of thymine. I‐methyl‐thymine and 3‐methylthymine (in alkaline solutions, 10‐2N NaOH) at 300° and 77°K were measured. It was shown, that at 300°K only 3‐HT‐ tautomeric thymine monoanion fluoresces; at 77°K emissions of both monoanionic species contribute to the observed luminescence spectrum.