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Organotin(IV) chemistry is nowadays in a continuous expansion due to the biological and medicinal potential found for some of these species. Within this study, the cytotoxic activity of several organotin(IV) compounds was investigated on two lung cancer cell lines (H522 and SK‐MES‐1) and on a normal lung cell line in order to have an overview of the toxicity and the selectivity of these derivatives. Moreover, the synthetic protocols, as well as the structural particularities of the novel organotin(IV) species, are also discussed. Hydrolysis of [2‐{(CH2O)2CR}C6H4]2SnPh2 [R = H (1), Me (2)] with p‐toluenesulfonic acid as a proton source afford the expected derivatives [2‐(O═CR)C6H4]2SnPh2 [R = H (3), Me (4)]. When hydrochloric acid is used in these reactions, a chlorine‐phenyl exchange took place in addition to the removal of the acetal fragments and the following products [2‐(O═CR)C6H4]2SnPhCl [R = H (5), Me (6)] were isolated. Treatment of 5 with 2 equiv of 3‐aminomethylpyridine in neat affords the imino(aryl)tin compound 2‐(3′‐PyCH2N═CH)C6H4]2SnPhCl (7). The reaction between 6 and potassium nicotinate allows the isolation of the organotin(IV) carboxylate [2‐{O═C (CH3)}C6H4]2SnPh[O(O)CC5H4N‐3] (8). Compounds 1–8 were characterized by multinuclear NMR spectroscopy in solution, mass spectrometry, and IR spectroscopy, and their molecular structures were confirmed by X‐ray diffraction analysis. Compounds 1–8 were investigated for their antitumoral effects on Homo sapiens lung cancer cell lines (H522 and SK‐MES‐1) and on a normal bronchial epithelial cell line, BEAS‐2B. [ABSTRACT FROM AUTHOR]

The reaction of 4‐[(CH2O)2CH]C6H4Br (1) with n‐BuLi, followed by addition of HgCl2 to the in situ formed organolithium derivative, affords [4‐{(CH2O)2CH}C6H4]2Hg (2). Deprotection of the formyl groups of 2 in presence of p‐TsOH (p‐Ts = 4‐MeC6H4SO3) leads to [4‐(O=CH)C6H4]2Hg (3). Condensation reactions of 3 with 2‐aminopyridine (2‐pyNH2), 4‐aminopyridine (4‐pyNH2), 2‐aminomethylpyridine (2‐pyCH2NH2), and 4‐aminomethylpyridine (4‐pyCH2NH2), in CH2Cl2, affords the novel diorganomercury(II) compounds of type [(E)‐4‐(RN=C)C6H4]2Hg [R = 2′‐py (4), 4′‐py (5), 2'‐pyCH2‐ (6), 4′‐pyCH2 (7)]. Compounds 2 and 3 were useful precursors for the preparation of the corresponding homocoupling products [4‐{(CH2O)2CH}C6H4]2 (8) and [4‐(O=CH)C6H4]2 (9) in presence of catalytic amounts of palladium(II) acetate. Compounds 2–9 were characterized by multinuclear magnetic resonance (NMR) (1H, 13C{1H}, and 199Hg{1H}, when appropriate) and infrared (IR) spectroscopy and by mass spectrometry. The molecular structures of 3, 5, 6, 8, and 9 were determined by single‐crystal X‐ray diffraction. Highlights: A quick, easy, and economic synthesis was optimized for bis(4‐formylphenyl)mercury(II).Syntheses of novel homoleptic diorganomercury(II) compounds with imine functional groups were optimized to give good to excellent yields in mild conditions with easy workup.All diorganomercury(II) compounds were characterized by multinuclear (1H, 13C{1H}, and 199Hg{1H} NMR) and IR spectroscopy as well as mass spectrometry and, for three compounds with imine functional groups, the molecular structure was determined by single‐crystal X‐ray diffraction.The use of diorganomercury(II) compounds as starting materials for homocoupling reactions, in presence of catalytic amounts of palladium(II) acetate, was investigated. [ABSTRACT FROM AUTHOR]

The reaction of 4‐[(CH2O)2CH]C6H4Br (1) with n‐BuLi, followed by addition of HgCl2 to the in situ formed organolithium derivative, affords [4‐{(CH2O)2CH}C6H4]2Hg (2). Deprotection of the formyl groups of 2 in presence of p‐TsOH (p‐Ts = 4‐MeC6H4SO3) leads to [4‐(O=CH)C6H4]2Hg (3). Condensation reactions of 3 with 2‐aminopyridine (2‐pyNH2), 4‐aminopyridine (4‐pyNH2), 2‐aminomethylpyridine (2‐pyCH2NH2), and 4‐aminomethylpyridine (4‐pyCH2NH2), in CH2Cl2, affords the novel diorganomercury(II) compounds of type [(E)‐4‐(RN=C)C6H4]2Hg [R = 2′‐py (4), 4′‐py (5), 2'‐pyCH2‐ (6), 4′‐pyCH2 (7)]. Compounds 2 and 3 were useful precursors for the preparation of the corresponding homocoupling products [4‐{(CH2O)2CH}C6H4]2 (8) and [4‐(O=CH)C6H4]2 (9) in presence of catalytic amounts of palladium(II) acetate. Compounds 2–9 were characterized by multinuclear magnetic resonance (NMR) (1H, 13C{1H}, and 199Hg{1H}, when appropriate) and infrared (IR) spectroscopy and by mass spectrometry. The molecular structures of 3, 5, 6, 8, and 9 were determined by single‐crystal X‐ray diffraction. Highlights: A quick, easy, and economic synthesis was optimized for bis(4‐formylphenyl)mercury(II).Syntheses of novel homoleptic diorganomercury(II) compounds with imine functional groups were optimized to give good to excellent yields in mild conditions with easy workup.All diorganomercury(II) compounds were characterized by multinuclear (1H, 13C{1H}, and 199Hg{1H} NMR) and IR spectroscopy as well as mass spectrometry and, for three compounds with imine functional groups, the molecular structure was determined by single‐crystal X‐ray diffraction.The use of diorganomercury(II) compounds as starting materials for homocoupling reactions, in presence of catalytic amounts of palladium(II) acetate, was investigated. [ABSTRACT FROM AUTHOR]

Four novel Cu(II) chelates were synthesized by reacting hydrated CuCl2 and Cu(CH3COO)2 with two derivatives of 1,3,4‐thiadiazolethiosemicarbazone. The structures and geometries of the synthesized complexes were deduced applying the alternative analytical and spectral tools confirming the complexes to have the formulae [(LH)Cu(Cl)]•0.5H2O, [(LH)Cu(OAc)(H2O)2]•0.5H2O, [(LCl)Cu(Cl)(H2O)2]•H2O and [(LCl)Cu(OAc)]; where LH and LCl are phenyl and p‐chlorophenyl derivatives of 1,3,4‐thiadiazolethiosemicarbazone ligands, respectively (deprotonated form). IR spectral data confirmed the coordination of the ligands to the copper center as monobasic tridentate in the thiol form. Thermal analysis, UV–Vis spectra and magnetic moment assured the geometry around the copper center to be square planar, trigonal bipyramid and octahedral which have been confirmed by the computational studies. The two ligand derivatives and their copper complexes were applied to evaluate their binding modes with SS‐DNA via UV–Vis spectral titration and viscosity measurements. The DNA‐binding constant (kb) values of the investigated derivatives were calculated and compared with ethidium bromide in order to assess their mode of binding with DNA. Moreover, docking study of these complexes was carried out to recognize the drug–DNA interactions and to calculate their binding energies. [ABSTRACT FROM AUTHOR]

The compounds [2‐(Me2NCH2)C6H4]2SbL (L = ONO2 (2), OSO2CF3 (3)) and [PhCH2N(CH2C6H4)2]SbL (L = ONO2 (5), OSO2CF3 (6)) were prepared by reacting [2‐(Me2NCH2)C6H4]2SbCl (1) and [PhCH2N(CH2C6H4)2]SbCl (4), respectively, with the appropriate silver(I) salt in a 1:1 molar ratio. The new species 2–6 were structurally characterized in solution using multinuclear NMR and in the solid state using infrared spectroscopy. The solid‐state structures for compounds 2, 4 and 6, as well as for the hydrolysis ionic product [{2‐(Me2N+HCH2)C6H4}{2‐(Me2NCH2)C6H4}SbOH][CF3SO3]− (3h) were determined using single‐crystal X‐ray diffraction. Medium to strong intramolecular N→ Sb interactions were observed in all these four compounds, thus resulting in hypercoordinated organoantimony(III) species 14‐Sb‐6 in 2 and 10‐Sb‐4 in the cation of 3h and in 4 and 6. Compounds 1–6 and the starting amines PhCH2NMe2 and PhCH2N(CH2C6H4Br‐2)2 were investigated as catalysts in the Henry (nitroaldol) addition of nitromethane to benzaldehyde. The activity of compounds 1–6 resulted as an effect of the cooperation of the positively charged antimony with the negatively charged nitrogen. [ABSTRACT FROM AUTHOR]

The diorganodiselenides (pzCH2CH2)2Se2 (1) and (PhtzCH2)2Se2 (2) were prepared by reacting Na2Se2 with 1‐(2‐bromoethyl)‐1H‐pyrazole and 4‐(chloromethyl)‐2‐phenylthiazole, respectively, while the reactions between 1‐(2‐bromoethyl)‐1H‐pyrazole or 4‐(chloromethyl)‐2‐phenylthiazole and the lithium organoselenolates [2‐(Et2NCH2)C6H4]SeLi and [2‐{O(CH2CH2)2NCH2}C6H4]SeLi in a 1:1 molar ratio resulted in the heteroleptic diorganoselenium(II) compounds [2‐(Et2NCH2)C6H4](R)Se (R = pzCH2CH2 (3) or PhtzCH2 (5)) and [2‐{O(CH2CH2)2NCH2}C6H4](R)Se (R = pzCH2CH2 (4) or PhtzCH2 (6)). The diorganotin(IV) bis(organoselenolato) derivatives of type R2Sn(SeCH2CH2pz)2 (R = 2‐(Me2NCH2)C6H4 (7) or Me (8)) were obtained by reacting (pzCH2CH2)SeNa with the appropriate diorganotin(IV)dichloride in a 2:1 molar ratio. All compounds were investigated using NMR spectroscopy (1H, 13C, 77Se, 119Sn as appropriate) and ESI+ mass spectrometry. The molecular structures of 2 and 6 were determined using single‐crystal X‐ray diffraction. The formation of a 10–Se–3 hypercoordinated species was evidenced for 6 in the solid state, as a consequence of the C,N coordination behaviour of the 2‐{O(CH2CH2)2NCH2}C6H4 group. Compounds 1, 7 and 8 were investigated for their antiproliferative activity towards the mouse colon carcinoma C26 cell line with the preliminary results showing a better activity than 5‐fluorouracil. [ABSTRACT FROM AUTHOR]