2-Chloropyrimidine-4-carboxylic acid , with CAS number of 149849-92-3, can be called 1-[5-(Trifluoromethyl)-1,3,4-thiadiazol-2-yl]piperazine ; piperazine, 1-[5-(trifluoromethyl)-1,3,4-thiadiazol-2-yl]- .