Seleno‐Nucleobases and Their Water‐Soluble Ruthenium–Arene Half‐Sandwich Complexes: Chemistry and Biological Activity

Abstract

AbstractHalf‐sandwich organometallic ruthenium complexes of seleno‐nucleobases, 3 and 4, were synthesized and characterized. The structures of both complexes were determined by X‐ray crystallography and are the first crystal structures of ruthenium complexes with seleno‐nucleobases. Interestingly, 3 self‐assembles aided by adventitious water in DMF to give a tetranuclear square 3a·6H2O. Complex 4 is active against Jurkat and Molt‐4 cell lines but inactive against the K562 cell line, whereas 3 is completely inactive against all three cell lines. The free ligand 6‐selenopurine (1) and 6‐selenoguanine (2) are highly active against these cell lines. Compound 2, like its thio analogue, is unstable under UVA light, whereas 4 is stable under similar conditions, which suggests that the ruthenium complex could reduce problems associated with the instability of the free ligand, 2, under irradiation.