| Solganol, Myochrysine and Auranofin are gold drugs used in the treatment of Rheumatoid Arthritis, a degenerative disease of the joints. [Au(CN) 2]− is the biotransformation product of these drugs, which has been found in the urine of patients who have been treated with these drugs. Concerns over the expected toxicity of [Au(CN)2] − have led us to seek a less toxic analogue which may have a similar therapeutic profile. The thiocyanate complex seems to be a logical choice if cyanide is playing a role in the toxicity. The syntheses, and characterization of the salts of [Au(SCN)2]− are presented. The salts have some unusual, unexpected characteristics, namely, as the counter ion decreases in size the anion forms an oligomeric chain of gold atoms with varying interaction distances. The crystallography has shown that the [Au(SCN) 2]− is an intact anionic species. For the Ph 4P+ salt, the anion is a monomer whereas for the (n-Bu) 4N+ salt is a dieter, and as the cation decreases in size an oligomer forms. The oligomerization is observed only in the solid state of the salts. The oligomeric complexes have an unusual emission, which is not present in the monomeric complexes. The Na+, K +, Rb+, Cs+, NH4+ , (n-Bu)4N+, and Me4N + salts emit at various wavelengths, and are due entirely on the Au-Au interaction. |
