
Trichloroisocyanuric acid, or more formally 1,3,5-trichloro-1,3,5-triazinane-2,4,6-trione, is a disinfectant, chlorinating agent, and industrial deodorant. It’s the active ingredient in “chlorine” tablets used to keep swimming pools safe. Its preparation was first reported by C. H. G. Hands and F. Whitt in 1948.
More about this molecule from CAS.