A series of organotin complexes with Sn–S bonds of formulae Me₂Sn(SR)₂ (1); Et₂Sn(SR)₂ (2); (n-Bu)₂Sn(SR)₂ (3); Ph₂Sn(SR)₂ (4); R₂Sn(SR)₂ (5); Me₃SnSR (6); Ph₃SnSR (7) (R = 3,5-di-tert-butyl-4-hydroxyphenyl) were synthesized and characterized by elemental analysis, ¹H, ¹³C NMR, and IR. The crystal structures of compounds 1, 4, 5, and 7 were determined by X-ray diffraction analysis. The tetrahedral geometry around the Sn center in the monocrystals of 1, 4, 5, and 7 was confirmed by X-ray crystallography. The high radical scavenging activity of the complexes was confirmed spectrophotometrically in a DPPH-test. The binding affinity of 1–7 and the starting R₂SnCl₂ (8) towards tubulin through their interaction with SH groups of proteins was studied. It was found that the hindered organotin complexes could interact with the colchicine site of tubulin, which makes them promising antimitotic drugs. Compounds 1–8 were tested for their in vitro cytotoxicity against human breast (MCF-7) and human cervix (HeLa) adenocarcinoma cells. Complexes 1–8 were also tested against normal human fetal lung fibroblast cells (MRC-5). Complexes 2–4 and 8 exhibit significantly lower cytostatic activity against the normal MRC-5 cell line compared to the tumor cell lines MCF-7 and HeLa used. A high activity against both cell lines 250 nM (MCF-7) and 160 nM (HeLa) was determined for the triphenyltin complex 7 while the introduction of hindered phenol groups decreases the cytotoxicity of the complexes against normal cells.

Development of efficient extractants for the separation of actinides and lanthanides in the technologies of nuclear fuel cycle is one of the most urgent and complex tasks in modern nuclear energetics. New family of 4,7-dichloro-1,10-phenanthroline-2,9-dicarboxylic acid diamides based on cyclic amines was synthesized and shown to exhibit high selectivity in the La/Am pair separation (SF (Am/La ≈ 10)) and in the Am/Eu pair separation (SF (Am/Eu ≈ 12)). It was shown that pyrrolidine derived diamide is more efficient extractant for americium, curium and lanthanides from highly acidic HNO₃ solution than its non-cyclic N,N,N′,N′-tetraalkyl analogues. The structures of synthesized compounds were studied in details by IR, NMR spectroscopy, and single crystal X-ray diffraction. According to spectroscopy data, incorporation of aromatic rings to the amide fragment of ligand leads to complex dynamic behavior in solutions what is believed to strongly affect the extraction ability of synthesized ligands.