| 摘要 |
<p>5,7-Dihydroxy-N-(aryl)-1,2,4-triazolo[1,5-a]pyrimidine-2-sulfonamides of formula <CHEM> wherein X represents H, F, Cl, Br, alkyl or alkoxy, Y represents H, F, Cl or Br, R represents H, alkyl or alkyoxy, Z represents H, Cl or Br, are prepared by cyclization of N-(3-(((aryl)amino)sulfonyl)-1H-1,2,4-triazol-5-yl)amines with malonyl halides under acidic conditions. With the addition of a phosphorus oxyhalide, malonic acid can be used in place of the malonyl halides and the 5-7-dihydroxy-1,2,4-triazolo[1,5-a]pyrimidine can be directly converted to the corresponding 5,7-dihalo derivative.</p> |
