6- Benzylidenehydrazino-3-methyluracil

A second synthetic route involves the ring contraction of certain 7-azapteridinones. Treatment of 6-benzylidenehydrazino-3-methyluracils, for example (602a), with sodium... 

Nitrozation of 6-benzylidenehydrazino-3-methyluracil 4 took place with concurrent cyclization to 5. The latter was also obtained from the nitroso and the nitro derivatives 6 and 7 upon treatment with a mixture of sodium or potassium nitrate and acetic and sulfuric acids (75CPB1885) (Scheme 6). 

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