CXV.—Aromatic arsonic and arsinic acids

Frank Lee Pyman, William Colebrook Reynolds
1908 Journal of the Chemical Society Transactions  
FOR some time past we have been engaged in the preparation of aryl derivatives of arsenic, and, a s two recent publications (0. and R. Adler, Ber., 1908, 41, 931; Benda and Kahn, Ber., 1908, 41, 1672) show t h a t there are other chemists covering somewhat the same ground, we have deemed i t advisable to publish our results so far as they have proceeded. We had prepared 2-aminotolyl-5-arsonic acid and its acetyl derivative some months ago, and these substances together with sodium
more » ... odium p-aminophenylarsonate have been tested physiologically and clinically. Ehrlich had shown that the toxicity of sodium p-acetylaminophenylarsonate is considerably less than that of sodium y-aminophenylarsonate, and the same relationship has now been found between the corresponding toluidine derivatives ; sodium 2-aminotolyl-5-arsonate has about the same toxicity as sodium p-aminophenylarsonate, whilst t h a t of sodium 2-acetylaminotolyl-5-arsonate is very considerably less. These substances have been speciaIly intended for use i n t r y panosominsis (sleeping sickness), and experiments on their effect on diff went strains of trypanosomes have shown that, whilst certain strains were destroyed by the treatment, others were more resistant. I n the treatment of syphilis, however, these substances have proved especially eficacious, and the results obtained in this connexion are exceedingly promihing. Since 0. and R. Adler and Benda and Kahn (Zoc. cit.) have already published the method of preparation and physical properties of these substances, we need only state t h a t we confirm their results, and supplement them by recording the state of hydration of the sodium salts, this latter being important from the point of view of their use in medicine. I n the preparation of p-aminophenylarsonic acid and 2-aminotolyl-5-arsonic acid, we have obtained as by-products the corresponding bisaminoarylarsinic acids, which have been briefly alluded to by Benda and Kahn (Zoc. cit.), but, as these have been i n our hands for some time past, we give in this communicatiori a full description of their preparation and properties. The constitution of these substances has been proved by replacing the arsenic acid residue by iodine according to the method used by Ehrlich arid Bertheim ( B e y . , 1907, 40, 3292) for y-aminophenylarsonic acid. The arsinic acids are now being investigated clinically with a view to their possible use in trypanosomiasis and syphilis, but the results are as yet not sufficiently conclusive,
doi:10.1039/ct9089301180 fatcat:2qyyqqprrjesjfor3ysnkzqvzu