Sodium aurothiosulfate, or sanocrysin, is the inorganic compound with the formula Na3[Au(S2O3)2]·2H2O.

[1][2][3] The salt is typically prepared by reduction of gold(III) chloride with thiosulfate:[3] The compound was first synthesized in 1845 by Mathurin-Joseph Fordos and A. Gélis who were researching chemicals used in the Daguerrotype photographic process.

[4][5] It went out of interest until 1924 when it was noted as a chemotherapeutic agent for tuberculosis by Holger Møllgaard in Copenhagen.

[8] The first placebo-controlled trial was probably conducted in 1931, when sanocrysin was compared with distilled water for the treatment of tuberculosis.

The general approach would employ sodium or ammonium thiosulfate in place of cyanide salts as lixiviants.