PROCESS FOR THE PREPARATION OF NOVEL N-SUBSTITUTED HALOGENOMETHYLENEINDOXYLS

摘要

Process for the Preparation of Novel N-Substituted Halogenomethyleneindoxyls Novel N-substituted halogenomethyleneindoxyls ¢N-sub-stituted halogeno-(3-oxa¢2H!indol-2-ylidene)acetic acids! can be prepared according to a new process by reacting N-substituted anilides with dihalogenomaleic anhydrides or derivatives thereof. The novel N-substituted halogenomethyleneindoxyls are valuable intermediates for the preparation of pharmaceutically active compounds having an antiallergic action.