Substituted benzimidazolecarboxylic acids of formula (I), wherein R1 and R2 independently are hydrogen, C1-6 alkyl or C3-6 cycloalkyl, are prepared in a four-step synthesis starting from N-acyl-4-haloanilines of formula (II), wherein R1 is as defined above, R3 is C1-4 alkyl and X is chlorine or bromine.
公式(I)中的取代
苯并咪唑羧酸,其中R1和R2独立地为氢、C1-6烷基或C3-6环烷基,可以从公式(II)中的N-酰基-4-卤代
苯胺开始进行四步合成,其中R1如上定义,R3为C1-4烷基,X为
氯或
溴。