Ein Verfahren zur Herstellung von Mehrfach mit Tritium Markiertem Thymin BZW. Thymidin

After a survey about the preparation of tritium labelled thymine and thymidine a new synthesis for the preparation of manifold labelled thymine respectively thymidine is given. 5‐Formyluracil was reduced to 5‐hydroxymethyluracil (5‐HMU) in a phosphate buffer at pH 7,0 with tritium gas using Pd0/BaSO 4 as catalyst. The tritium labelled 5‐HMU was hydrogenated to [ 4 methyl‐ 3 H] thymine with tritium gas using a mixture of Palladium black and Palladiumchloride in dry dioxane. The specific activity was 2550 GBq/mmol. [methyl‐ 3 H] Thymidine was obtained in a usual enzymatic synthesis.