Water-Soluble Rhenium Phosphine Complexes Incorporating the PhC(X) Motif (X = O, NH): Structural and Cytotoxicity Studies.

Reaction of [ReOCl(PPh)] or [ReOI(PPh)] with 2,2'-diphenylglycine (dpgH) in refluxing ethanol afforded the air-stable complex [ReO(dpgH)(dpg)(PPh)] (). Treatment of [ReO(OEt)I(PPh)] with 1,2,3-triaza-7-phosphaadamantane (PTA) afforded the complex [ReO(OEt)I(PTA)] (). Reaction of [ReOI(PTA)] with dpgH led to the isolation of the complex [Re(NCPh)I(PTA)]·0.5EtOH (·0.5EtOH). A similar reaction but using [ReOX(PTA)] (X = Cl, Br) resulted in the analogous halide complexes [Re(NCPh)Cl(PTA)]·2EtOH (·2EtOH) and [Re(NCPh)(PTA)Br]·1.6EtOH (·1.6EtOH). Using benzilic acid (2,2'-diphenylglycolic acid, benzH) with afforded the complex [ReO(benz)(PTA)][PTAH]·EtOH (·EtOH). The potential for the formation of complexes using radioisotopes with relatively short half-lives suitable for nuclear medicine applications by developing conditions for [Re(NCPh)(dpg)I(PTA)] ()[ReO] in a 4 h time scale was investigated. A procedure for the technetium analog of complex [Re(NCPh)I(PTA)] () from Tc[TcO] was then investigated. The molecular structures of - are reported; complexes - have been studied using in vitro cell assays (HeLa, HCT116, HT-29, and HEK 293) and were found to have IC values in the range of 29-1858 μM.