Ligand scrambling reactions of gold(I) complexes and their implications for chrysotherapy

296

ABSTRACTS

~A~OFIlEVUJCGou)ANDs#vER D.F. Williams, Institute of Medical and Dental Bioengineering, This presentation

is concerned

gold with tissues. implantable

with some aspects of the interaction

This is primarily

of interest in those applications

devices or for other sustained contact with tissues.

all of the interactions

Although

‘biocompatible’ concept.

Biocompatibility

is concerned

with

will deal with some of the

of gold, and especially silver, in context of the new concepts of

In particular,

it is important

to stress that biocompatibility

as ‘the ability of a material to perform with an appropriate application’.

between metals such as silver and where these metals are used in

between materials and tissues and this presentation

aspects of the biocompatibility these interactions.

University of Liverpool, Leg 3f3X.

has been defined

host response, in a specific

for a long time it was assumed that in order for a material to be

it had to be inert and provoke little or no response, this is no longer an acceptable

It is the nature and appropriateness

of them and this is of considerable

of the interactions

significance

which are important,

Silver is known to be reactive with tissues and certain tissue components demonstrate

useful properties

interactions.

The paper will cover certain components

tissues, including

in a variety of applications,

protein adsorption

not the lack

in the case of metals such as gold and silver.

and desorption

local tissue response and systemic distributions,

but it is abie to

perhaps on the basis of these

of the interactions phenomena,

between these metals and

corrosion, metal-protein

binding, the

These effects will be discussed in the context of

the general theories of biocompatibility.

LJGANDscFiAMt3LlNG ~OFGOU)(I)alM~ANDlHElRIMPUCATK)NS R)R cHRysoTHwlw Department

of Chemistry,

Gold(l) complexes

C. F. Shaw Ill, A. Hormann-Arendt,

University of Wisconsin-Milwaukee,

are liabile to ligand exchange.

chemists, pharmacologists

and physicians

53201, USA.

This property

studying

and M. Stanch,

has been long recognized

their physiochemical,

biological

properties.

One possible consequence

of these scrambling

Complexes

which contain two different

ligands may undergo ligand scrambling

by

and medicinal

reactions has often escaped attention. to form the symmetrically

ligated complexes: K 2LAux.

eq

‘L AuL_

Since the scrambling

+

+

react&s

AuX_”

are rapid, n&ear

average signal due to rapid site exchange tertiaryphosphine

complexes

magnetic

of the ligands.

resonance techniques

may observe only an

Recently our group has used the

of gold(l) cyanides as model systems for studying this reaction.

synthetic routes were employed

and will be discussed.

The effects on the equilibrium

Several

constant

(Keq)

of the reaction due to the variation of the alkyl and aryl groups and of the solvent, ionic strength and complex

concentration

were examined.

Related sytems;eported

by other groups, including

cases where the solid state form is an ionic

complex

-}, will also be discussed.

The triethylphosphinegold(I)

(AuL2

}{AuX

of the new anti-arthritic auranofin undergoes triethylphosphinegold(I) also been measured

3 rug auranofin.

a similar scrambling thioglucose,

cyanide is an analogue

Although we have not been able to demonstrate reaction, we have documented

does scramble.

and will be reported.

Supported

The equilibrium

that

that its probable

metabolite,

constant for this reaction has

by the US NIH (AR399021.