A new industrial process excellent in yield and purity for preparing a compound of the formula:
or a salt thereof in a less number of steps with a synthetic pathway without proceeding via nitroso compounds,
wherein
R1 is lower alkyl, aryl, ar(lower)alkoxy or heterocyclic group, each of which may be substituted with halogen, and
R2 is cyclo(lower)alkyl, aryl or ar(lower)alkyl, each of which may be substituted with halogen.
一种产率和纯度极佳的新工业工艺,用于制备式化合物或其盐,其合成途径无需通过亚
硝基化合物,且步骤较少:
或其盐的新工业工艺,其合成途径无需通过亚
硝基化合物,且步骤较少、
其中
R1 是低级烷基、芳基、芳(低)级烷氧基或杂环基团,其中每个基团均可被卤素取代,以及
R2 为环(低级)烷基、芳基或芳(低级)烷基,其中每个基团均可被卤素取代。