4-Chloro-3-sulfamoylbenzoyl chloride is an organic intermediate for the synthesis of sulfonamides. It is harmful to water. Do not let undiluted or large amount of products contact groundwater, watercourses or sewage system. Do not discharge this reagent into the surrounding environment without government permission. In the field of medicine, 4-chloro-3-sulfamoylbenzoyl chloride is the intermediate of indapamide, which is a long-acting and effective antihypertensive drug.