Preparation of 6‐azauracil‐5‐ 3 H and 6‐azauridine‐5‐ 3 H of high molar activity

Catalytic reductive dehalogenation of 5‐bromo‐6‐azauracil with carrier‐free tritium led to 6‐azauracil‐5‐ 3 H of a molar activity of 19.0 Ci/mmole. The reaction conditions for the catalytic reductive dehalogenation were examined in tracer experiments. Microbial transformation was used for the preparation of 6‐azauridine‐5‐ 3 H from 6‐azauracil‐5‐ 3 H. 6‐Azauridine‐5‐ 3 ‐ H was prepared at a molar activity of 18.8 Ci/mmole. In both compounds the stability of tritium was investigated in an aqueous medium at 100°C.