119Sn, 15N, 13C, and 1H NMR spectra were studied for [2-(dimethylaminomethyl)phenyl]stannanes, R1R2R3R4Sn or R1R2R24Sn, where R1, R2, and R3 are 1-butyl, Cl or Br, the same or different, and R4 is 2-(dimethylaminomethyl)phenyl. The occurrence of intramolecular interaction between the nitrogen and tin atoms was demonstrated based on changes in the characteristic values of the NMR parameters of these nuclides (δ(15N), δ(119Sn), J(119Sn,15N), and their interrelations, as well as on the relatively high values of the coupling constants 3J(119Sn,13C(CH2)).

The 13C and 119Sn NMR spectra of some mono-n-butyltin(IV) compounds in solution of non-coordinating (CDCl3 and CD3NO2) and coordinating ((CD3)2SO and C5D5N) solvents have been studied. From the values of delta(119Sn), 1J(119Sn,13C) and additional 13C NMR parameters an evaluation of the coordination numbers of the central tin atom and the shapes of coordination polyhedra around the tin atom has been carried out.

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A series of novel and highly active acetylcholinesterase and butyrylcholinesterase inhibitors derived from substituted benzothiazoles containing an imidazolidine-2,4,5-trione moiety were synthesized and characterized. The molecular structure of 1-(2,6-diisopropyl-phenyl)-3-[(1R)-1-(6-fluoro-1,3-benzothiazol-2-yl)ethyl]-imidazolidine-2,4,5-trione (3g) was determined by single-crystal X-ray diffraction. Both optical isomers are present as two independent molecules in the triclinic crystal system. The lipophilicity of the compounds was determined as the partition coefficient log Kow using the traditional shake-flask method. The in vitro inhibitory activity on acetylcholinesterase from electric eel and butyrylcholinesterase isolated from equine serum was determined. The inhibitory activity on acetylcholinesterase was significantly higher than that of the standard drug rivastigmine. The discussed compounds are also promising inhibitors of butyrylcholinesterase, as some of the prepared compounds inhibit butyrylcholinesterase better than the internal standards rivastigmine and galanthamine. The highest inhibitory activity (IC50 = 1.66 μmol/L) corresponds to the compound 1-(4-isopropylphenyl)-3-[(R)-1-(6-fluorobenzo[d]thiazol-2-yl)ethyl]imidazolidine-2,4,5-trione (3d). For all the studied compounds, the relationships between the lipophilicity and the chemical structure as well as their structure-activity relationships are discussed.

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The reactivity of (L(CN))(2)Sn (1) (where L(CN) is 2-(N,N-dimethylaminomethyl)phenyl-) towards various substrates containing E–Cl bond(s) has been studied (E = C, Si, Ge and Sn). Alkyl chlorides like chloroform or dichloromethane reacts with 1 to form (L(CN))(2)SnCl(2) and unidentified by-products in poor yields. The reaction of benzoyl chloride with 1 at low temperature yielded a thermally unstable product (L(CN))(2)Sn(Cl)C(O)Ph (2) which was isolated and characterized by both multinuclear NMR spectroscopy and X-ray diffraction techniques. The vicinity of the central tin atom in 2 reveals trigonal bipyramidal geometry. Attempts to oxidize 2 by dioxygen to give the corresponding organotin(IV) benzoate failed. On the other hand, the reaction of the in situ prepared (L(CN))(2)Sn=O (synthesized by the reaction of 1 with dioxygen) with PhCOCl resulted in the formation of the desired organotin(IV) benzoate (L(CN))(2)Sn(Cl)C(=O)OPh (3). The reaction of 1 with Ph3GeCl yielded triphenylgermyl-substituted diorganotin(IV) chloride (L(CN))(2)Sn(Cl)GePh(3) (4) which subsequently gave mixed diorganotin(IV) chloride-oxide [(L(CN))(2)SnCl](2)O (5) upon loss of the GePh(3) moiety in the air. When the same reaction was carried out in benzene instead of chloroform a unique [Ph(3)Ge](4)[Sn(6)O(8)] cluster (6) was obtained. Similarly, the reaction of 1 with Ph3SiCl provided triphenylsilyl-substituted diorganotin(IV) chloride (L(CN))(2)Sn(Cl)SiPh(3) (7) which was then oxidized to (L(CN))(2)Sn(Cl)OSiPh(3) (8). The unprecedented reaction of 1 with (n-Bu)(3)SnCl provided the distannane (L(CN))(2)Sn(Cl)SnBu(3) (9) which could be oxidized by dioxygen to a distannoxane (L(CN))(2)Sn(Cl)OSnBu(3) (10). In addition, the solid-state structures of 3, 5, 6 and 8 were determined by the X-ray diffraction techniques.