6447. Neoarsphenamine

Nomenclature

CAS number: 457-60-3
Sulfoxylic acid mono[[[5-[(3-amino-4-hydroxyphenyl)diarsenyl]-2-hydroxyphenyl]amino]methyl] ester monosodium salt; [5-[(3-amino-4-hydroxyphenyl)arseno]-2-hydroxyanilino]methanol sulfoxylate sodium; arsphenamine methylenesulfoxylic acid sodium salt; 3,3′-diamino-4,4′-dihydroxyarsenobenzenemethylenesulfoxylate sodium; Neosalvarsan (Hoechst); Collunovar; N.A.B.; Neo-Arsoluin; Vetarsenobillon; Novarsenobillon; Arsevan; Novarsan; Novarsenobenzol; Miarsenol.
C13H13As2N2NaO4S; mol wt 466.15.
C 33.50%, H 2.81%, As 32.14%, N 6.01%, Na 4.93%, O 13.73%, S 6.88%.

Description and references

Medicinal grade contains a small amount of inert inorganic salts and some solvent. The National Formulary requires 19+% As. Prepn from arsphenamine + sodium formaldehydesulfoxylate: Krumwiede, J. Am. Pharm. Assoc. 8, 795 (1919); Heyl, Miller, ibid. 11, 432 (1922); Dohr, US 1549465 (1925); Kober, US 1564859 (1926); Kraft et al., SU 158388 (1962). Physicochemical properties and toxicity: H. N. Wright et al., J. Pharmacol. Exp. Ther. 73, 12 (1941).

Chemical structure

Properties

Yellow powder; odorless or slight odor. Oxidizes in air, becoming darker and more toxic; higher temps accelerate the oxidation; hence marketed in air-evacuated ampuls or filled with a nonoxidizing gas. Very sol in water; sol in glycerol. Slightly sol in alcohol or acetone. Practically insol in chloroform, ether. Its aq soln is practically neutral, unlike arsphenamine, which is acid.

Therapeutic Category (Veterinary)

Has been used in contagious pleuropneumonia, babesiasis, equine petechial fever, eperythrozoonosis.