PROCESS FOR PRODUCING CRYSTAL OF BENZENESULFONAMIDE DERIVATIVE, AND NOVEL CRYSTAL OF INTERMEDIATE THEREFOR AND PROCESS FOR PRODUCING THE SAME

摘要

A process for producing high-purity crystals which comprises using a polar solvent as a good solvent (e.g., an alcohol or an alcohol/water mixed solvent) and water as a poor solvent to crystallize the benzenesulfonamide derivative represented by the following formula (1); novel crystals of the nitrobenzenesulfonamide derivative represented by the following formula (2), which is an intermediate for the derivative (1); and a process for producing the novel crystals.