| 摘要 |
<p>The invention provides a process for the preparation of 1,2,3-thiadiazol-5-yl ureas of the general formula I in which R1 represents hydrogen or a C1-C4 alkyl radical, R2 represents a C1-C4 alkyly, C5-C8-cycloakyl, methyl-C5-C8 cycloalkyl, phenyl, halophenyl, C1-C4-alkylphenyl, C1-C4 alkoxyphenyl, nitrophenyl, trifluoromethylphenyl, pyridyl or a pyrimidyl radical, wherein a 1,2,3-thiadiazole-5-carbohydroxamic acid derivative of the formula II in which R3 represents hydrogen or an alkall metal or the equivalent of a alkali earth metal or a monovalent metal equivalent, is reacted with an acid halide of the general formula R4 - X in which R4 represents a C1-C4 alkylcarbonyl, chloroacetyl, dichloroacetyl, trichloroacetyl, metloxyacetyl, 2-chloro-propionyl, 3-chloropropionyl, 4-chlorobutyryl, bromoacetyl, 2-bromopropionyl or 3-bromopropionyl, C1-C4 alkoxycarbonyl, benzoyl, 4-chlorobenzoyl, 3-chlorobenzoyl, 2-chlorobenzoyl, 4-methoxybenzoyl, 3-methoxybenzoyl, 2-methoxybenzoyl, 4methylbenzoyl, 3-methylbenzoyl, 2-methylbenzoyl, phenylsulphonyl, 4-tolylsulphonyl, 4-bromopilcnylsulphonyl, 4chlorophenylsulphonyl, 2-Ditrophenylsulphonyl, 4-fluoro-phenylsulphonyl, methylsulphonyl, ethylsulphonyl or a benzylsulphonyl radical, and X represents a halogen atom, in an inert organic solvent in the presence of an acid-bind-ing agent to form an acylated 1,2,3-thiadiazole-5-carbohy-droxamic acid derivative of the general formula IV and the compound of the general formula IV so obtained is reacted with an amine of the general formula V in which R1 and R2 have the meanings given above, and the reaction product is isolated. The process of the invention makes it possible to prepare the ureas in a technically simple manner in good yields and without the necessity of isolating any hazardous intermediates.</p> |
