反应详情

温度

25 °C

59.6 parts of cyclohexylaminosulfonyl chloride and 26.9 parts of pyridine were introduced through two feed lines, into a stirred solution of 39.6 parts of N-carbomethoxy-O-methylisourea in 300 parts of ethyl acetate, at from 15° to 20° C. After having been stirred for 4 hours at 25° C., the reaction mixture was extracted once with water and once with 0.5 N hydrochloric acid and was then dried and concentrated under reduced pressure. This gave 79 parts of N-carbomethoxy-N'-cyclohexylsulfamyl-O-methylisourea, of nD25 =1.4970. After trituration with a small amount of ether, the compound crystallized, and these crystals melted at 84°-86° C. 15 parts of this product were dissolved in a mixture of 9 parts of 50% strength by weight sodium hydroxide solution and 20 parts of water and the reaction solution was stirred for 4 minutes at from 55° to 60° C. It was then cooled, extracted once with ether, and stirred into a mixture of 9.5 parts of concentrated hydrochloric acid and 10 parts of water. Filtering off the product, washing with water and drying gave 9 parts of 6-cyclohexyl-3-methoxy-5,6-dihydro-1,2,4,6-thiatriazin-5-one-1,1-dioxide, of melting point 173°-177° C. This constitutes active compound No. 3.

1. extractionthe reaction mixture was extracted once with water and once with 0.5 N hydrochloric acid
2. customwas then dried
3. concentrationconcentrated under reduced pressure