Disodium aurothiomalate is a

chemical compound A chemical compound is a chemical substance composed of many identical molecules (or molecular entities) containing atoms from more than one chemical element held together by chemical bonds. A molecule consisting of atoms of only one element ...

with the formula AuSCH(CO₂Na)CH₂CO₂Na. In conjunction with its mono protonated derivative, this

coordination complex A coordination complex consists of a central atom or ion, which is usually metallic and is called the ''coordination centre'', and a surrounding array of bound molecules or ions, that are in turn known as '' ligands'' or complexing agents. M ...

or closely related species are used to treat

rheumatoid arthritis Rheumatoid arthritis (RA) is a long-term autoimmune disorder that primarily affects joints. It typically results in warm, swollen, and painful joints. Pain and stiffness often worsen following rest. Most commonly, the wrist and hands are inv ...

, under the tradename Myochrysine. The thiomalate is

racemic In chemistry, a racemic mixture, or racemate (), is one that has equal amounts of left- and right-handed enantiomers of a chiral molecule or salt. Racemic mixtures are rare in nature, but many compounds are produced industrially as racemates. ...

in most formulation.

Structure

Disodium aurothiomalate is a

coordination polymer A coordination polymer is an inorganic or organometallic polymer structure containing metal cation centers linked by ligands. More formally a coordination polymer is a coordination compound with repeating coordination entities extending in 1, 2 ...

. The salt CsNa₂Au₂T(TH) salt (T = thiomalate³⁻, TH = monoprotonated thiomalate²⁻) is related to disodium aurothiomalate but is easier to crystallise and characterise by

X-ray crystallography X-ray crystallography is the experimental science determining the atomic and molecular structure of a crystal, in which the crystalline structure causes a beam of incident X-rays to diffract into many specific directions. By measuring the angles ...

. The compound is polymeric with Au-S-Au-S^... chains with succinoyl groups attached to the sulfur atoms. The structure of the related drug Aurothioglucose is also polymeric with two-coordinate gold(I) centers. In such compounds, the efficacy results from the compound in solution, the structures of such solution species are often poorly understood. Medical texts sometimes suggest that free Au⁺ ions exist in this and related gold(I) compounds, but the Au- thiolate bonding is highly

covalent A covalent bond is a chemical bond that involves the sharing of electrons to form electron pairs between atoms. These electron pairs are known as shared pairs or bonding pairs. The stable balance of attractive and repulsive forces between atom ...

and free gold ions do not exist in solution. Whereas simple gold thiolates are lipophilic, the

carboxylate In organic chemistry, a carboxylate is the conjugate base of a carboxylic acid, (or ). It is an ion with negative charge. Carboxylate salts are salts that have the general formula , where M is a metal and ''n'' is 1, 2,...; ''carboxylat ...

substituents render disodium aurothiomalate soluble in water. Disodium aurothiomalate contains no Au-C bonds, so it is not an

organometallic compound Organometallic chemistry is the study of organometallic compounds, chemical compounds containing at least one chemical bond between a carbon atom of an organic molecule and a metal, including alkali, alkaline earth, and transition metals, and s ...

in the formal sense.

Mechanism of action

The mechanism of action of disodium aurothimalate is unknown.

Side effects

Disodium aurothiomalate can cause photosensitive rashes, gastrointestinal disturbance, and kidney damage.

References

{{Gold compounds Gold(I) compounds Immunosuppressants Coordination polymers Gold–sulfur compounds

Structure

Mechanism of action

Side effects

See also

References