作者:Frederick Kurzer、Jane L. Secker
DOI:10.1016/0040-4020(77)80391-8
日期:1977.1
The interaction of ethoxycarbonyl isothiocyanate with semicarbazides or thiosemicarbazides produces 1-ethoxycarbonyl-2-thiobiureas or bithioureas, respectively. The former are cyclisable to 2-ethoxycarbonamido-5-hydroxy-l,3,4-thiadiazole in acid, or to 2(H)-carbamoyl-3-hydroxy-5-alkylthio-1,2,4-triazoles, and thence to 3-hydroxy-5-mercapto-1,2,4-triazole in alkaline media. The ring-closure of the
乙氧基羰基异硫氰酸酯与氨基脲或硫代氨基脲的相互作用分别产生1-乙氧基羰基-2-硫代双脲或联硫脲。前者可与酸中的2-乙氧基碳酰胺基-5-羟基-1,3,4-噻二唑或2(H)-氨基甲酰基-3-羟基-5-烷硫基1,2,4-三唑环化,因此在碱性介质中生成3-羟基-5-巯基-1,2,4-三唑 1-乙氧基羰基联硫脲的闭环类似地进行,在酸的影响下提供5-氨基(或巯基)-2-乙氧基碳酰胺基-1,3,4-噻二唑。碱的作用产生了衍生自3-羟基-5-巯基-1,2,4-三唑的化合物;在选定的实例中,对2(H)-苯基硫代氨基甲酰基衍生物的分离阐明了该反应的过程。1-乙氧基羰基联硫脲的水合肼解产生4-氨基-3-肼基-5-巯基-1,2,4-三唑。