2-[[4-(carbamoylamino)phenyl]-(carboxymethylsulfanyl)arsanyl]sulfanyla cetic acid

Thiocarbarsone,Lilly,US,1951

121 g of thioglycolic acid and 100 g of carbarsone oxide are reacted in a solution of 128 g of sodium bicarbonate in 2 liters of water.
The mixture is heated on a steam bath for 20 minutes. The reaction mixture is then cooled and filtered to remove a small amount of insoluble material. The filtrate is diluted with about 600 cc of water and is acidified with concentrated hydrochloric acid.
On treating the reaction mixture with acid, di-(carboxymethylthio)-pcarbamidophenylarsine precipitates, and is separated by filtration and dried.
Di -(carboxymethylthio)-p-carbamidophenylarsine thus prepared was obtained as a white amorphous solid, soluble in dilute alkali. It contained about 19.85% of arsenic as compared with the calculated amount of 19.09%.

Antiamebic

Poison by intraperitoneal and intravenous routes. Moderately toxic by ingestion. See also ARSENIC COMPOUNDS, MERCAPTANS, and ESTERS. When heated to decomposition it emits very toxic fumes of As and SOx