反应详情

1.2 g N-(4-[2-(4-methyl-2-oxo-piperidine-1-carboxamido)-ethyl]-benzenesulfonyl)-N'-cyclohexyl-thio-urea (m.p. 179°-181° C., prepared from 4-[2-(4-methyl-2-oxo-piperidine-1-carboxamido)-ethyl]-benzenesulfonamide and cyclohexyl-isocyanate in acetone in the presence of potassium carbonate) are dissolved in 75 ml of acetone and 10 ml of water. At 0° C., a solution of 0.1 g of sodium nitrite in 5 ml of water is added to this solution, subsequently 0.8 ml of 5 N acetic acid is added dropwise, and agitation is continued for 2 hours at 0° C. Subsequently, the acetone is evaporated under reduced pressure, the product is suction-filtered and reprecipitated from dilute ammonia. After recrystallization from dilute acetone, N-(4-[2-(4-methyl-2-oxo-piperidine-1-carboxamido)-ethyl]-benzenesulfonyl)-N'-cyclohexyl urea has a melting point of 176°-178° C., and with the product prepared according to Example 8, shows no depression.

1. additionis added dropwise
2. customSubsequently, the acetone is evaporated under reduced pressure
3. filtrationthe product is suction-filtered
4. customreprecipitated from dilute ammonia
5. customAfter recrystallization from dilute acetone, N-(4-[2-(4-methyl-2-oxo-piperidine-1-carboxamido)-ethyl]-benzenesulfonyl)-N'-cyclohexyl urea
6. customwith the product prepared