mono-adducts of the parent carbonohydrazide with aroyl isothiocyanates cyclise spontaneously to 2-aroylamido-5-hydroxy-1,3,4-thiadiazoles under the conditions of their synthesis, but a symmetrical di-adduct from carbonohydrazide and benzoyl isothiocyanate is stable and isolable.
芳
硫基异
硫氰酸酯在二甲基甲酰胺中与亚苄基或1-苯基碳酰
肼加成反应,得到单加合物的近定量产率。4-芳基-1-(亚苄基
氨基)
氨基甲酰基-或4-芳基-1-
苯胺基
氨基甲酰基-3-
硫代
氨基
脲。它们被碱环化成3-芳基-5-巯基-
1,2,4-三唑,并被酸环化成2-芳基酰胺基-5-羟基-1,3,4-
噻二唑。母体碳酰
肼与芳基异
硫氰酸酯的单加合物在其合成条件下自发环化成2-芳基酰
氨基-5-羟基-1,3,4-
噻二唑,但由碳酰
肼与
苯甲酰基异硫氰酸酯对称的二加合物稳定且稳定。可隔离的。