Tatum and Cooper1 and Gruhzit and his associates2 showed that mapharsen possesses therapeutic values against experimental syphilis and trypanosomiasis comparable to those of the arsphenamines. Foerster and his associates3 in their paper stated that mapharsen is a potent antisyphilitic agent and "its use in a small group of closely observed patients has been followed by clinical results which at the present time appear as approximately equal to those which we would expect from the use of arsphenamine."
CHEMISTRY AND TOXICOLOGY
Mapharsen, the hemialcoholate of meta-amino-para-hydroxyphenylarsine oxide, generally referred to as "arsenoxide," is a relatively simple, uniform chemical substance2 Ehrlich and Bertheim,4 Voegtlin5 and Rosenthal6 described this substance as the active therapeutic agent in spirochetosis.
Arsenoxide is the precursor substance in the synthesis of arsphenamine, and it is also the main breakdown product of the oxidation of arsphenamine, as illustrated:
AsO As = As