AMPHIPHILIC BIS(THIOLATO)-NICKEL(II), BIS(THIOLATO)-PALLADIUM(II) ANDBIS(THIOLATO)-PLATINUM(II) COMPLEXES WITH DIPHOSPHINE OR PHOSPHINOARSINE LIGANDS

The novel complexes (M(L-L)(H-2dmsucc-S,S')] [M=Ni, Pd or Pt; L-L=1,2- bis(diphenylphosphino)ethane, dppe; M = Pd or Pt, L-L = 1 -diphenylars ino-2-diphenylphosphinoethane, dadpe; H-4dmsucc = dimercaptosuccinic a cid) and [Ni(dppe) (H-3msucc)] (H-3msucc = mercaptosuccinic acid) have been prepared and characterised. The reactions of sodium 2,3-dimercap topropanesulfonate, sodium 1-thio-beta-D-glucopyranosate and dithiothr eitol with [M(L-L)X2] (M = Ni, Pd or Pt; X = Cl or Br) were investigat ed by (P-{H})-P-31-H-1 NMR spectroscopy. The P-31 NMR chemical shifts, P-31-P-31 and Pt-195-P-31 coupling constants, and the conformations o f chelate rings (derived from H-1-H-1 coupling constants) in mixed-lig and products from these reactions are discussed. The use of these thio late ligands has enabled solubilisation of several complexes containin g dppe or dadpe ligands in aqueous media. The cytotoxicities of dppe a nd dadpe complexes of Pd and Pt with dimercaptosuccinic acid were inve stigated.