Related Experiment Video
Updated: Jul 4, 2026

A Direct, Early Stage Guanidinylation Protocol for the Synthesis of Complex Aminoguanidine-containing Natural Products
Published on: September 9, 2016
Aurocyanide, dicyano-aurate (I), a pharmacologically active metabolite of medicinal gold complexes
G G Graham1, M W Whitehouse, G R Bushell
1School of Medical Sciences, University of New South Wales, Darlinghurst, Sydney, NSW, 2010, Australia. g.graham@unsw.edu.au
Abstract:
The aurocyanide anion, Au(CN) (2) (-) , is a human metabolite of several anti-rheumatic gold complexes containing monovalent gold (I) bound to a sulphur ligand. This article reviews some of the chemical and pharmacological properties of this intriguing metabolite, and reports its anti-arthritic and anti-inflammatory activity in rats. Au(CN) (2) (-) is generated from the therapeutic gold complexes by small amounts of hydrogen cyanide, HCN, produced from thiocyanate, SCN(-), by myeloperoxidase (MPO) an enzyme in neutrophils which normally produces hypochlorite, OCl(-). Thus, Au(CN) (2) (-) is formed at sites of inflammation where activated neutrophils are present. This includes atherosclerotic lesions as well as inflamed joints. MPO also oxidises Au(CN) (2) (-) to Au(III) complexes such as Au(CN) (4) (-) .Au(CN) (2) (-) is normally a very stable monovalent gold complex. In a biological context, only low concentrations are ever present at both extracellular and intracellular sites. However, Au(CN) (2) (-) produced locally may facilitate the cellular uptake and hence the therapeutic and toxic effects of gold drugs. Au(CN) (2) (-) may also be involved in a redox cycle where Au(CN) (2) (-) is oxidised to Au(CN) (4) (-) which is, in turn, reduced back to Au(CN) (2) (-) by endogenous thiols. There are still many questions to be resolved concerning Au(CN) (2) (-) including its intrinsic toxicity and the extent to which it may contribute to the overall anti-arthritic activities of the gold-thiolates from which it is formed in vivo.
Related Concept Videos
Aryldiazonium Salts to Azo Dyes: Diazo Coupling
Physical Properties of Amines
Phase II Reactions: Miscellaneous Conjugation Reactions
A key example involves the conjugation of cyanide ions, which impair cellular respiration and alter hemoglobin into non-oxygen-carrying cyanmethemoglobin. To neutralize this threat, a sulfur atom from thiosulphate is transferred to the cyanide ion, catalyzed by the enzyme rhodanese, resulting in an inactive compound called thiocyanate. The production of...
Formation of Complex Ions
Aldehydes and Ketones with HCN: Cyanohydrin Formation Overview
EDTA: Chemistry and Properties

