Synthetic routes of sulfonamide derivatives: A brief review

Sulfonamides (SO₂-NH-) have been the center of drug structures as they are quite stable and well tolerated in human beings. The sulfonamides are very important protected intermediates of amines, with several types of biological activities. Due to the broad applicability of sulfonamides, it is desirable to find general and effective methods for their synthesis. Different methods have been adopted to synthesize sulfonamides. Here is a comprehensive review which provides several of the most common and recent methods of sulfonamide synthesis: via sulfonyl chloride; starting from thiols, sulfonic acids, sulfenamide and sulfonate esters; or using indium, copper, and palladium as catalysts or Grignard reagents and metal oxides.