Aurothioglucose

Overview
Aurothioglucose, also known as gold thioglucose, is a chemical compound with the formula AuSC6H11O5. This derivative of the sugar glucose is used to treat rheumatoid arthritis.

History
Throughout history, gold was used to cure diseases, although the efficacy was not established. In 1935, gold drugs were reported to be effective for the treatment rheumatoid arthritis. Although many patients reacted positively to the drug, gold thioglucose was not uniformly effective.

Two gold drugs remain in active clinical use for this purpose in the United States: sodium aurothiomalate (gold sodium thiomalate) and Aurothioglucose, sold under the trade names Myochrysine and Solgonal, respectively. In the United Kingdom, only sodium aurothiomalate and auranofin are used.

Medicinal chemistry
Gold thioglucose features gold in the oxidation state of +I, like other gold thiolates. It is a water-soluble, non-ionic species that is assumed to exist as a polymer. Under physiological conditions, an oxidation-reduction reaction leads to the formation of metallic gold and sulfinic acid derivative of thioglucose.
 * 2 AuSTg →  2 Au  +  TgSSTg
 * TgSSTg +  H2O  →  TgSOH  +  TgSH
 * 2 TgSOH →  TgSO2H  +  TgSH
 * Overall: 2 H2O +  4 AuSTg  →  4 Au  +  TgSO2H  +  3 TgSH

(where AuSTg = gold thioglucose, TgSSTg = thioglucose disulfide, TgSO2H = sulfinic acid derivative of thioglucose)

Preparation
Gold thioglucose can be prepared by treating gold bromide with thioglucose solution saturated with sulfur dioxide. Gold thioglucose is precipitated with methanol and recrystallized with water and methanol.

Miscellaneous observations
In recent research, it has found that injection of gold thioglucose in the mouse induces obesity. Aurothioglucose has an interaction with the antimalarial medication Hydroxychloroquine.