Pyrimidine derivatives XII. A convenient preparation of 6‐formylpyrimidinedione and 2‐ and 3‐formylpyridine derivatives from corresponding nitrooxymethyl derivatives

The convenient preparation of 6‐fomylpyrimidinedione derivatives and 2‐ and 3‐formylpyridine are described. Thus, 5‐bromo‐1,3‐dimethyl‐ ( 1a ), 5‐bromo‐3‐methyl‐1‐(2‐nitrooxyethyl)‐ ( 1b ), and 5‐bromo‐3‐methyl‐1‐(3‐nitrooxypropyl)‐2,4(1 H ,3 H )‐pyrimidine‐dione ( 1c ) were converted to the corresponding 6‐formyl compounds 2a, 2b , and 2c , respectively, in excellent yields by the reaction with triethylamine and 1,4‐diazabicyclo[2.2.2]octane. These 6‐formylpyrimidinedione derivatives are key intermediates for the preparation of 6‐carbon‐carbon substituted compounds, which are expected to be potential antitumor and antiviral agents. Similarly, 2‐(and 3‐)formylpyridine ( 9a (and 9b )) were obtained by the reaction of 2‐(and 3)nitrooxymethylpyridine ( 8a (and 8b )) with 1,4‐diazabicyclo[2.2.2]octane.