CHED 727

Synthesis of ruthenium antitumor agents

Heather K. Izumi and Wayne L. Smith. Department of Chemistry, Colby College, 5750 Mayflower Hill, Waterville, ME 04901,

Dimethylsulfoxide complexes of Ru(II) exhibit antitumor activity and are relatively nontoxic. Previous studies have shown that trans-[Cl2(Me2SO)4Ru] binds more rapidly to DNA than the cis-isomer and causes greater disruption of the DNA structure due to crosslinking. Efforts in our laboratory with Ru complexes indicate that cis-complexes are more easily obtained than the trans-isomers. Initial attempts have involved preparation of cis-[Cl2(Me2SO)4Ru] and photochemical conversion to the trans-isomer. We are preparing robust Ru complexes which will efficiently bind to DNA. Besides Ru(DMSO)4X2 (where X=Cl, NO2, NO), we will focus on complexes with polypyridyl coligands such as trans-[Ru(bpy)2X2] and mer-[Ru(tpy)X3] (where bpy=2,2-dipyridine and tpy=2,2’:6’,2"-terpyridine). Characterization of the complexes will involve infrared and ultraviolet spectroscopy, conductivity, and magnetic susceptibility.