DIORGANOTIN(IV) ANTITUMOUR AGENTS. AQUEOUS AND SOLID-STATE COORDINATION CHEMISTRY OF NUCLEOTIDES WITH R2SnCl2

Abstract This paper reports a solution and solid-state study of the aqueous nucleotide coordination chemistry of the diorganotin(IV) antitumor agents, R2SnCl2 (R[dbnd]C2H5, η-C4H9). Interaction between (C2H5)2SnCl2 with 2′-deoxyguanosine-5′-monophosphate in neutral aqueous solution was investigated using trans-[Osen2 (η-H2] (CF3SO3)2 as a 1H NMR recognition probe; the diorganotin(IV) complexes were formulated as [R2Sn (Nu)H2O]n (Nu = adenosine-5′-monophosphate, cytidine-5′-monophosphate (GMP) and guanosine-5′-monophosphate (GMP), respectively). These were prepared by the reaction of R2SnCl2 with nucleotides under near physiological conditions. The complexes were characterized by analysis, FT-IR and 500 MHz 1H, and 31P NMR. The nucleotides gave polymeric species in which Sn(IV) is directly coordinated to the phosphate group. No evidence was found for coordination through donor atoms of the nucleosides.