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Abstract: A novel Keggin unit supported transition metal complex [Cu(4,4′-bipy)]2[SiW12O40{Cu(4,4′-bipy)}4]·(OH)2 ·H2O (1) (4,4′-bipy=4,4′-bipydine) has been hydrothermally synthesized and structurally characterized by IR spectroscopy, TG analyses and single-crystal X-ray diffraction. The result of the X-ray crystallography analysis exhibits that four chains simultaneously connect with the [SiW12O40]4− units via W–Ot–Cu bridges constructing an infinitely one-dimensional fourfold-chain structure. [Copyright &y& Elsevier]

An organic–inorganic hybrid compound constructed from a Keggin-type molybdophosphate polyoxoanion, a CuI coordination cation and a protonated 1,10-phenanthroline subunit, namely 1,10-phenanthrolinium bis­(1,10-phenanthroline)­copper(I) dodeca­molybdophosphate, (C12H10N2)[Cu(C12H8N2)2][PMo12O40] or (H2phen)[Cu(phen)2][PMo12O40], has been prepared under hydro­thermal conditions and structurally characterized by single-crystal X-ray diffraction. The polyoxoanion is constructed from a central PO4 tetra­hedron which shares its O atoms with four {Mo3O16} trinuclear groups, each of which is made up of three edge-sharing {MoO6} octa­hedra. In the [Cu(phen)2]+ counter-cation, the Cu atom is coordinated by four N atoms from two 1,10-phenanthroline ligands. [ABSTRACT FROM AUTHOR]

The asymmetric unit of the title compound, C7H10N+·C7H4NO3S−, is composed of one saccharinate anion and one 2,6-dimethyl­pyridinium cation. They are linked by an N—H⋯O hydrogen bond. Furthermore, π–π inter­actions are observed between saccharinate anions and 2,6-dimethyl­pyridinium cations. [ABSTRACT FROM AUTHOR]

Abstract: Up to now, bismuth(III) complexes with thiosemicarbazones have been comparatively rare. Here, a main group seven-coordinated bismuth(III) complex [Bi(L)(NO3)2(CH3CH2OH)] (1) (HL=2-acetylpyridine N(4)-phenylthiosemicarbazone) has been synthesized and characterized by elemental analysis, IR, 1H NMR and single-crystal X-ray diffraction studies. The cytotoxicity data suggest that 1 exhibits higher in vitro antiproliferative activity in four human cancer cells tested. Its possible apoptotic mechanism has been evaluated in HepG2 cells. Compound 1 promotes a dose-dependent apoptosis in HepG2 cells and the apoptosis is associated with an increase in intracellular reactive oxygen species (ROS) production and reduction of mitochondrial membrane potential (MMP). [Copyright &y& Elsevier]

We investigate the molecular structure, vibrational and electronic absorption spectra, and electronic hyperpolarizabilities of trans and cis isomers of 4-hydroxyazobenzene (HOAB) via density functional theory. Results show that the azo dye exhibits a high third-order nonlinear optical response and good optical transparency. Both the basis set and the functional are important influences on the results obtained when calculating the absorption spectrum and NLO response. We also study the effect of the solvent on the electronic absorption spectrum to assess the ability of the functional to reproduce the experimental spectrum in combination with a suitable solvent model. Our calculations show that the SMD model of Truhlar et al. handles the electrostatic and the non-electrostatic effects of hydrogen-bonding solvents on the absorption spectrum better than the traditional polarizable continuum model does. In addition, our results indicate that the dye trans-HOAB exhibits a high second hyperpolarizability and excellent optical transparency. Also, although the second hyperpolarizability of cis-HOAB is much lower than that of trans-HOAB, it is non-negligible when calculating the optical nonlinearity of HOAB under an optical pump. We also examine the effect of frequency dispersion on second harmonic generation. This study provides the basis for further research on the spectroscopic and nonlinear optical properties of novel azo dyes and other π-conjugated compounds. [ABSTRACT FROM AUTHOR]

Two metal complexes [Cd(L) 2 ]·0.275H 2 O( 1 ) and [In(L) 2 ]NO 3 ( 2 ) (HL = 2-benzoylpyridine N (4)-cyclohexylthiosemicarbazone) have been synthesized and structurally characterized by elemental analysis, a number of spectroscopic methods (IR, UV-vis, NMR), mass spectrometry, and X-ray crystallography. The Schiff’s base ligand forms hexacoordinated complexes having octahedral geometry for Cd(II) and In(III) complexes, respectively. The synthesized compounds were tested for antiproliferative activity and showed the ability to kill HepG2 cells (human hepato cellular carcinoma) significantly, especially 2 with IC 50 = 2.02 ± 0.14 μM. Of particular note is the fact that complex 1 has ca 12-fold lower toxicity in the normal hepatocyte QSG7701 cells than in the hepatocellular carcinoma HepG2 cells. In addition, complex 2 also exhibited excellent luminescent property. Upon the addition of 1 equiv of In 3+ ion, 200-fold fluorescence enhancement of HL at λ em = 504 nm has been observed. Moreover, the fluorescent color change (from transparent to light-green) could be observed by naked eyes under the light of 365 nm. These findings can expand the applications of thiosemicarbazone derivatives in the fields of colorimetric and fluorescent probes. [ABSTRACT FROM AUTHOR]

Abstract: Main group metal complex [Bi(HL)(NO3)3] (1), where HL=2-acetylpyrazine N(4)-pyridylthiosemicarbazone, has been synthesized and characterized by elemental analysis, IR, MS and single-crystal X-ray diffraction studies. The interesting monomeric 8-coordinate bismuth(III) complex 1 is depicted with one electron pair (6s2) of the bismuth(III) atom, one N2S tridentate neutral thiosemicarbazone, two monodentate and one bidentate nitrate ions, respectively. In vitro biological studies have indicated that the bismuth complex 1 has shown effective antibacterial and anticancer activities especially with MIC=15.6μg/mL against Gram positive bacteria Bacillus cereus and IC50 =1.6 μM against K562 leukemia cell lines, respectively, comparable to positive control. [Copyright &y& Elsevier]

Two nickle complexes of 2-acetylpyrazine thiosemicarbazones have been synthesized, Growth inhibition assays indicated complex 2 has the highest tumor cells selectivity. • Two nickel complexes of 2-acetylpyrazine thiosemicarbazone have been synthesized and structurally characterized. • The growth inhibition assays suggested that complex 2 has the highest tumor cells selectivity. In this article, two nickel complexes of 2-acetylpyrazine thiosemicarbazone formulated as [Ni(L1) 2 ]·CH 3 OH (1) and [Ni 2 (L2) 3 ]ClO 4 ·C 2 H 5 OH (2) (HL1 = 2-acetylpyrazine N4-methylthiosemicarbazone, HL2 = 2-acetylpyrazine N4-dimethylthiosemicarbazone), have been synthesized and structurally characterized. The antibacterial activities of the two complexes and ligands were studied. It is found that the ligand HL2 and its corresponding complex displayed effective antimicrobial activity against the tested bacterial. Besides, the growth inhibition assays indicated that complex 2 and the two proligands are capable of showing inhibitory activity against the human hepatocellular carcinoma HepG2 cells, and the subsequent toxicity study on normal QSG7701cells showed that complex 2 has the highest tumor cells selectivity, and its IC 50 values is 7.21 times higher than in HepG2 cells. [ABSTRACT FROM AUTHOR]

In the structures of 1 and 2, N-containing thiosemicarbazide ligands, Lewis acid, and oxidation catalyst coexist within a confined space providing a particular environment for the efficient conversion of the aldehyde/ketone with the in situ generated hydroxylamine to form oximes. • Hybrids 1 and 2 were successfully synthesized and characterized. • The coexistence of N-containing thiosemicarbazide ligands, Lewis acid and oxidation catalyst provide a particular environment for the efficient conversion of aldehyde/ketone with the in situ generated hydroxylamine to form the oximes by one-pot procedure. • The hybrids 1 and 2 display high catalytic activity and selectivity for the oximation of ketones and aldehydes. Two inorganic-organic hybrid materials, [Co(L) 2 ] 2 Na 2 [ β -Mo 8 O 26 ]·9H 2 O (1) and [Fe(L) 2 ] 2 Na 2 [ β -Mo 8 O 26 ]·9H 2 O (2) (HL = 2-acetylpyrazine N4-methyl thiosemicarbazone) have been synthesized and characterized by elemental analyses, infrared (IR) spectroscopy, thermal gravimetric analysis (TGA), powder X-ray diffraction (PXRD) and single-crystal X-ray diffraction. The hybrids 1 and 2 were explored in the oximation of aldehydes and ketones with in situ generated hydroxylamine by a one-pot procedure. In the crystal structures of 1 and 2 , N-containing thiosemicarbazide ligands, Lewis acid, and oxidation catalyst octamolybdate coexist within a confined space providing a promising synergistic catalytic way. Hybrids 1 and 2 displayed high catalytic activity and selectivity for the oximation of aldehydes and ketones. [ABSTRACT FROM AUTHOR]

The rising in situ chemical oxidation (ISCO) technologies based on polymerization reactions have advanced the removal of emerging contaminants in the aquatic environment. However, despite their promise, uncertainties persist regarding their effectiveness in eliminating structurally complex contaminants, such as sulfonamide antibiotics (SAs). This study elucidated that oligomerization, rather than mineralization, predominantly governs the removal of SAs in the carbon materials/periodate system. The amine groups in SAs played a crucial role in forming organic radicals and subsequent coupling reactions due to their high f - index and low bond orders. Moreover, the study highlighted the robust adhesion of oligomers to the catalyst surface, facilitated by enhanced van der Waals forces and hydrophobic interactions. Importantly, plant and animal toxicity assessments confirmed the nontoxic nature of oligomers deposited on the carbon material surface, affirming the efficacy of carbon material-based ISCO in treating contaminated surface water and groundwater. Additionally, a novel classification approach, Δlog  k , was proposed to differentiate SAs based on their kinetic control steps, providing deeper insights into the quantitative structure-activity relationship (QSAR) and facilitating the selection of optimal descriptors during the oligomerization processes. Overall, these insights significantly enhance our understanding of SAs removal via oligomerization and demonstrate the superiority of C-ISCO based on polymerization in water decontamination.

Surface-enhanced Raman spectroscopy (SERS) has been widely applied in the identification and characterization of DNA structures with high efficiency. Especially, the SERS signals of the adenine group have exhibited high detection sensitivity in several biomolecular systems. However, there is still no unanimous conclusion regarding the interpretation of some special kinds of SERS signals of adenine and its derivatives on silver colloids and electrodes. This Letter presents a new photochemical azo coupling reaction for adenyl residues, in which the adenine is selectively oxidized to ( E )-1,2-di(7 H -purin-6-yl) diazene (azopurine) in the presence of silver ions, silver colloids, and electrodes of nanostructures under visible light irradiation. The product, azopurine, is first found to be responsible for the SERS signals. This photoelectrochemical oxidative coupling reaction of adenine and its derivatives is promoted by plasmon-mediated hot holes and is regulated by positive potentials and pH of solutions, which opens up new avenues for studying azo coupling in the photoelectrochemistry of adenine-containing biomolecules on electrode surfaces of plasmonic metal nanostructures.

Seven undescribed withanolides (1-7) and six artificial withanolides (8-13), along with 20 known compounds (14-33) were isolated from the aerial parts of Tubocapsicum anomalum. Their structures were confirmed by comprehensive spectroscopic analyses. The absolute configuration of compound 1 was defined by single-crystal X-ray crystallography. All isolates were evaluated for their antiproliferative effects against five human tumor cell lines (Hep3B, MDA-MB-231, SW480, HCT116 and A549), among which compound 24 (tubocapsanolide A) exhibited the highest activities against the MDA-MB-231 cells with an IC 50 value of 1.89 ± 1.03 μM. Further studies showed that 24 exhibited significant damage to mitochondria in MDA-MB-231 cells, including excess reactive oxygen species, decreased mitochondrial membrane potential, and apoptosis initiation. In addition, compound 24 also inhibited cell migration. These findings show that tubocapsanolide A may be a promising molecule for triple-negative breast cancer treatment and merit further evaluation., (Copyright © 2021 Elsevier Inc. All rights reserved.)

The gene PSEN2 encodes presenilin-2, a subunit of γ-secretase. Mutations in PSEN2 are not only related to Alzheimer's disease but are also involved in other diseases. The Chinese tree shrew ( Tupaia belangeri chinensis ) is a potential animal model for Alzheimer's disease, although little is known about its cDNA sequence, protein structure, and PSEN2 expression. To better understand PSEN2 in the tree shrew, we cloned this gene by rapid amplification of cDNA ends technology. Hence, we analyzed the sequence and molecular characteristics of PSEN2 mRNA, predicted its spatial structure, and analyzed its expression profiles. We found that tree shrew PSEN2 is 1539 base pairs in length and encodes 330 amino acids. It is homologous and genetically similar to humans (97.64% identity). The protein structure of tree shrew PSEN2 indicated similarities to human PSEN2, both being comprised of numerous transmembrane helices. However, tree shrew PSEN2 possesses seven α-helices, and thus lacks three compared with human PSEN2. Tree shrew PSEN2 mRNAs were ubiquitously detected in all tissues, with a tissue- and temporal-specific pattern. These results pave the way towards the function of tree shrew PSEN2, which will give insights into the mechanisms leading to neurodegenerative and other diseases in humans., Competing Interests: The authors declare no conflict of interest., (© 2020 Li et al. Published by IMR press.)

In the 1920s, Dr Otto Warburg first suggested the significant difference in energy metabolism between malignant cancer cells and adjacent normal cells. Tumor cells mainly adopt the glycolysis as energy source to maintain tumor cell growth and biosynthesis under aerobic conditions. Investigation on energy metabolism pathway in cancer cells has aroused the interest of cancer researchers all around the world. In recent years, plentiful studies suggest that targeting the peculiar cancer energy metabolic pathways, including glycolysis, mitochondrial respiration, amino acid metabolism, and fatty acid oxidation may be an effective strategy to starve cancer cells by blocking essential nutrients. Natural products (NPs) are considered as the "treasure trove of small molecules drugs" and have played an extremely remarkable role in the discovery and development of anticancer drugs. And numerous NPs have been reported to act on cancer energy metabolism targets. Herein, a comprehensive overview about cancer energy metabolism targets and their natural-occurring inhibitors is prepared.

Four metal complexes based on 2-benzoylpyridine N , N -dimethylthiosemicarbazone (Bp44mT) were designed. Free ligand and zinc(ii), diorganotin(iv), gallium(iii) and cadmium(ii) complexes all demonstrated pronounced activity, which was indicated using the growth inhibition test in vitro . Interestingly, most of the compounds were found to be selective against hepatocellular carcinoma (HepG2) cells but had little effect on normal hepatocyte (QSG7701) cells. In particular, Zn(Bp44mT) 2 ( 1 ) exhibited toxicity on QSG7701 cells which approximately 12-fold lower than that on HepG2 cells. The studies of mechanisms of action indicated that 1 induced reactive oxygen species (ROS) generation in a dose-dependent manner via the mitochondria transduction pathway. Protein analyses showed that 1 significantly promoted p21 and p53 gene expression, causing caspase-3 activation.

In this paper, synthesis and characterization of metal complexes [Cu 2 (L) 3 ]ClO 4 ( 1 ), [Ga(L) 2 ]NO 3 ·2H 2 O ( 2 ) and [In(L) 2 ]NO 3 ·H 2 O ( 3 ) (HL = 2-acetylpyridine N (4)-phenylthiosemicarbazone) was carried out, including elemental analysis, spectral analysis (IR, UV-vis, NMR), and X-ray crystallography. Complex 1 contains one S-bridged binuclear [Cu 2 (L) 3 ] + unit, where two Cu atoms display diverse coordination geometries: one being square planar geometry and the other octahedral geometry. Both 2 and 3 are mononuclear complexes, and the metal centers in 2 and 3 are chelated by two NNS tridentate ligands possessing a distorted octahedral geometry. Biological studies show that all the complexes possess a wide spectrum of modest to effective antibacterial activities and remarkable cytotoxicities against HepG2 cells, and 1 , in particular, with an IC 50 value of 0.19 ± 0.06 μM, is 113-fold and 28-fold more cytotoxic than HL and the antitumor drug mitoxantrone, respectively. In addition, 3 exhibits excellent photoluminescence properties. Upon the addition of 1 equiv of In 3+ ions, a remarkable fluorescence intensity of HL and fluorescent color change (from transparent to light-green) could be observed with 365 nm light, indicating that this ligand may be used as a promising colorimetric and fluorescent probe for In 3+ detection.

Objective: To explore the expression of gut-enriched Kruppel-like factor 4(KLF4) in gastric cancer, and its association with prognosis., Methods: Surgical specimens were collected from 264 patients undergoing radical surgery between 2004 and 2009 in the Affiliated Qianfoshan Hospital, Shandong University. KLF4 mRNA level of specimens was detected by real-time PCR. KLF4 protein expression was measured by immunohistochemistry on tissue microarray, which contained primary gastric cancer, corresponding para-cancerous tissue, and paired lymph node metastases., Results: Real-time PCR revealed that mRNA level of KLF4 was down-regulated in gastric cancer compared with paired normal gastric mucosa. Immunohistochemistry on tissue microarray showed gastric cancer tissues had significantly lower KLF4 levels compared with paired normal gastric tissues. By univariate and multivariate analysis, KLF4 was a significant predictor of survival and recurrence., Conclusion: KLF4 expression is significantly down-regulated in gastric cancer, and is an independent predictor of survival and recurrence.

Two NNS tridentate Schiff base ligands of 2-benzoylpyridine S-methyldithiocarbazate (HL(1)) and 2-benzoylpyridine S-phenyldithiocarbazate (HL(2)) and their transition metal complexes [Cu(2)(L(1))(2)(CH(3)COO)](ClO(4)) (1), [Zn(2)(L(1))(2)(ClO(4))(2)] (2), [Zn(L(2))(2)](3) have been prepared and characterized by elemental analysis, IR, MS, NMR and single-crystal X-ray diffraction studies. In the solid state, each of two Schiff bases remains in its thione tautomeric form with the thione sulfur atom trans to the azomethine nitrogen atom. Under similar prepared conditions, three new complexes showed distinctly different coordination modes depending on their coordinating preferences. Each copper atom in S-bridged dinuclear complex [Cu(2)(L(1))(2)(CH(3)COO)](ClO(4)) (1) is surrounded by five donor atoms in a square-pyramidal fashion (4+1). [Zn(2)(L(1))(2)(ClO(4))(2)] (2) is a dimer in which each zinc atom adopts a seven-coordinate distorted pentagonal bipyramidal geometry, while mononuclear [Zn(L(2))(2)] (3) has octahedral coordination geometry. Biological studies, carried out in vitro against selected bacteria, fungi, and K562 leukaemia cell line, respectively, have shown that different substituted groups attached at the dithiocarbazate moieties and metals showed distinctive differences in the biological property. Zinc(II) complexes 2 and 3 could distinguish K562 leukaemia cell line from normal hepatocyte QSG7701 cell line. Effect of the title compounds on Mitochondria membrane potential (MMP) and PI-associated fluorescence intensity in K562 leukaemia cell line are also studied. The title compounds may exert their cytotoxicity activity via induced loss of MMP., (Copyright © 2011 Elsevier Inc. All rights reserved.)

4-Cyclohexyl-1-(1-(pyrazin-2-yl)ethylidene)thiosemicarbazide (HL) and its transition metal complexes formulated as [Mn(L)(2)] (1) and [Ni(L)(2)] (2) have been prepared in 55-75% yield and characterized by elemental analysis, IR, MS, NMR and single-crystal X-ray diffraction studies. Biological activities of the synthesized compounds have been evaluated against selected Gram positive bacteria Bacillus subtilis, Gram negative bacteria Pseudomonas aeruginosa and the K562 leukemia cell line, respectively. The cytotoxicity data suggest that these compounds may be endowed with important biological properties, especially the nickel complex 2 with MIC = 31.2 μg/mL and IC(50) = 0.53 μM, respectively. Effect of the free ligand and its two complexes on Mitochondria membrane potential (MMP) and PI-associated fluorescence intensity as well as their effect on cell apoptosis in K562 leukemia cell line was also studied. The tested compounds may exert their cytotoxicity activity via induced loss of MMP., (Copyright © 2011 Elsevier Masson SAS. All rights reserved.)

Transition metal complexes Mn(L(1))(2) (1), Mn(L(2))(2) (2), Co(L(3))(2)Cl 4H(2)O (3), Zn(L(3))(2) DMF (4), Co(HL(4))(2)(ClO(4))(2) 3H(2)O (5) and Zn(L(5))(2) DMF (6) where HL(1)=2-acetylpyridine thiosemicarbazone, HL(2)=2-acetylpyridine N(4)-methylthiosemicarbazone, HL(3)=2-benzoylpyridine thiosemicarbazone, HL(4)=2-benzoylpyridine N(4)-methylthiosemicarbazone and HL(5)=2-benzoylpyridine N(4)-phenylthiosemicarbazone, have been synthesized. The complexes 1, 2, 5 and 6 were characterized by elemental analysis, IR spectra and single-crystal X-ray diffraction studies. Preliminary in vitro screening indicated that all the tested compounds showed significant antitumor activity against K562 leucocythemia cancer cell line., (Copyright (c) 2010 Elsevier Masson SAS. All rights reserved.)