Yanli Lu

Synthesis, crystal structures, and cytotoxicity of 2-benzoylpyridine N(4)-cyclohexylthiosemicarbazone and its zinc(II) and diorganotin(IV) complexes

[Zn(L)2] (1) and [(Ph)2Sn(L)(CH3COO)] (2), where HL = 2-benzoylpyridine N(4)-cyclohexylthiosemicarbazone, have been synthesized and characterized. The complexes show different coordination depending on their coordinating preferences. Biological studies carried out in vitro against human leukemia K562 cells show that the diorgantin(IV) complex, 2, has significant cytotoxicity with IC50 = 3.3 ± 0.5 μM.

Synthesis, Crystal Structures, and Cytotoxicity of Thiophene-2-carbaldehyde N(4)-Cyclohexylthiosemicarbazone and Its Diorganotin(IV) Complex

Thiophene-2-carbaldehyde N(4)-cyclohexylthiosemicarbazone C12H17N3S2 (HL) and diorganotin(IV) complex [Ph2Sn(L)Cl] (1) have been synthesized and characterized by elemental analysis, IR, and single-crystal X-ray diffraction. Complex 1 contains mononuclear neutral molecule composed of one five-coordinated diorganotin(IV) ion, one NS bidentate anionic thiosemicarbazone ligand, one chloridion, and two phenyl group, respectively. In vitro biological studies have indicated that coupling of HL with Ph2Sn(IV) leads to an enhancement of the cytotoxicity of the free ligand. Importantly, complex 1 could distinguish the human liver hepatocellular carcinoma HepG-2 cells from normal hepatocyte QSG7701 cells.

Synthesis, Characterization, Crystal Structure, and Cytotoxicity of a Diorganotin(IV) Complex with 2-Acetylpyridine N 4-Phenylthiosemicarbazone

A new diorganotin(IV) complex formulated as [(Me)2Sn(L) (CH3COO)] (1), where HL = 2-acetylpyridine N(4)-phenylthiose micarbazone, has been synthesized and characterized by elemental analysis, IR spectra, and single-crystal X-ray diffraction studies. Schiff base in its deprotonated form coordinates to tin(IV) via pyridine nitrogen atom and the nitrogen atom and sulfur atoms of the thiosemicarbazone moiety. The tin(IV) ion is seven-coordinated and adopts a distorted pentagonal bipyramidal geometry. Biological studies, carried out in vitro against the K562 leukemia cells, have shown that the coupling of HL to Me2Sn(IV) leads to an enhancement of the cytotoxicity of the free ligand.

A Main Group Gallium(III) Complex Derived from 2-Acetylpyrazine N4-phenylthiosemicarbazone: Synthesis, Crystal Structure and Biological Evaluation

Up to now, main group gallium(III) complexes with thiosemicarbazones have been comparatively rare. Here, a main group six-coordinated gallium(III) complex [Ga(L)2]NO3·H2O (1) (HL = 2-acetylpyrazine N4-phenylthiosemicarbazone) has been synthesized and characterized by elemental analysis, IR and UV/Vis spectroscopy, mass spectrometry, and single-crystal X-ray diffraction. The cytotoxicity data suggest that 1 exhibits significant antiproliferative activity in vitro against three human cancer cells. Its possible apoptotic mechanism has been evaluated in HepG2 cells. 1 induces a dose-dependent apoptosis in HepG2 cells and the apoptosis is associated with reduction of mitochondrial membrane potential.

Synthesis, Crystal Structure, and Biological Activity of an Mn(II) Complex Derived from 2,6-diacetylpyridine bis(N 4-methylthiosemicarbazone)

Transition metal complex [Mn(H2L)(H2O)2](CH3COO)2 (1), where H2L = 2,6-diacetylpyridine bis(N 4-methylthiosemicarba- zone), has been synthesized and characterized by elemental analysis, IR, mass spectrometry, and single-crystal X-ray diffraction. Complex 1 is depicted as a monomeric, seven-coordinated complex formed with one Mn(II) ion, one pentadentate N3S2 thiosemicarbazone ligand, and two oxygen atoms from two water molecules. Biological studies, carried out in vitro against K562 leukemia cells, have shown that the thiosemicarbazone moiety and its manganese(II) complex show distinctive differences in the biological property.

Palladium(II) and Antimony(III) Complexes Derived From 2-Benzoylpyridine N4-Phenylthiosemicarbazone: Synthesis, Crystal Structure, Antiproliferative Activity, and Low Toxicity on Normal Hepatocyte QSG7701 Cells

Two metal complexes [Pd(L)Cl] (1) and [Sb(L)Cl2] (2), where HL = 2-benzoylpyridine N4-phenylthiosemicarbazone, have been synthesized. Complex 1 was characterized by elemental analysis, IR, UV-Vis, NMR spectroscopy, and single-crystal X-ray diffraction studies. Complex 1 contains mononuclear neutral molecules composed of one N2S tridentate anionic thiosemicarbazone ligand and one ancillary chloride ion with a four-coordinated palladium ion. Both the two complexes exhibited enhanced cytotoxicity compared to the thiosemicarbazone and complex 2 could distinguish hepatocellular carcinoma HepG2 cells from normal hepatocyte QSG7701 cells.

A Diorganotin(IV) Complex of 2,6-Diacetylpyridine Bis(N4- Cyclohexylthiosemicarbazone): Synthesis, Crystal Structure, and Cytotoxicity

A diorganotin(IV) complex formulated as [(Me)2Sn(L)] (1) (H2L = 2,6-diacetylpyridine bis(N4-cyclohexylthiosemicarbazone) has been synthesized and structurally characterized by elemental analysis, IR, UV, and NMR spectroscopy, and single-crystal X-ray diffraction. Complex 1 contains mononuclear neutral molecules composed of one N3S2 pentadentate anionic thiosemicarbazone ligand and one (Me)2Sn(IV) group with a seven-coordinated tin ion. In vitro biological studies have indicated that complex 1 exhibited enhanced cytotoxicity compared to the thiosemicarbazone alone against human hepatocellular carcinoma HepG2 cells and could slightly distinguish HepG2 cells from normal hepatocyte QSG7701 cells.