sulfonamides

https://doi.org/10.1351/goldbook.S06114
amides of sulfonic acids RS(=O)2NR'2, e.g. PhS(=O)2NHCH3N-methylbenzenesulfonamide.
Source:
PAC, 1995, 67, 1307. 'Glossary of class names of organic compounds and reactivity intermediates based on structure (IUPAC Recommendations 1995)' on page 1369 (https://doi.org/10.1351/pac199567081307)