Organic arsenic compounds are chemical compounds that contain arsenic-carbon bonds. Some organic arsenic compounds, also known as "organoarsenicals ", are used industrially as insecticides, herbicides and fungicides. Despite the toxicity, arsenic compounds are well known. Organoarsenic chemistry has played a prominent role in the history of chemistry. The oldest known organic arsenic compound, cacodyl, is sometimes classified as the first synthetic organometallic compound. Salvarsan is one of the earliest drugs and earn a Nobel Prize for Paul Ehrlich. Various other arsenic compounds have also formerly been used
as antibotics or have other medical uses.
Applications
Medical chemistry: Arsphenamine, also known as Salvarsan, which was introduced in the early 1910s, is the first effective treatment for syphilis because it is toxic to the bacterium Treponema pallidum. It is also used to treat trypanosomiasis. This arsenic compound is the first modern chemotherapeutic agent. The project about Arsphenamine is the first organized team effort to optimize the bioactivity of lead compounds through systematic chemical modifications, which is the basis of modern pharmaceutical research. Neosalvarsan is a synthetic chemotherapeutic agent and an organic arsenic compound. It was launched in 1912 and replaced the more toxic and less water-soluble Arsphenamine as an effective treatment for syphilis. Arsenicin A is a naturally occurring organoarsenic compound that isolated from the marine sponge Echinochalina bargibanti. The compound possesses a cage-like structure similar to adamantane in which the four methanetriyl carbon bridgeheads and three of the six methylene bridges are replaced by arsenic atoms and oxygen atoms, respectively. Arsenicin A is active against promelocytic leukemia cells at lower concentrations than the drug Trisenox.
Agricultural chemistry: Arsanilic acid, also known as aminophenyl arsenate, is an organic arsenic compound which is an amino derivative of phenylarsonic acid with an amine group at the 4-position. It is a crystalline powder that was introduced medically as Atoxyl in the late 19th century and its sodium salt was used by injection at the beginning of the 20th century. Arsanilic acid has been used as a veterinary feed additive to promote growth and prevent or treat dysentery in poultry and swine for a long time. Methylarsonic acid is an organic arsenic compound of the formula CH3AsO3H2. It is a colorless, water-soluble solid. The salts of such compounds, such as disodium cacodylate, have been widely used as herbicides and fungicides in the cultivation of cotton and rice.
Fig.1. Treponema pallidum