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.
View Article and Find Full Text PDFSeven 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.
View Article and Find Full Text PDFThe gene encodes presenilin-2, a subunit of γ-secretase. Mutations in are not only related to Alzheimer's disease but are also involved in other diseases. The Chinese tree shrew () is a potential animal model for Alzheimer's disease, although little is known about its cDNA sequence, protein structure, and expression.
View Article and Find Full Text PDFIn 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.
View Article and Find Full Text PDFToxicol Res (Camb)
November 2019
In this article, three organotin complexes formulated as [(Me)Sn(HL)] (), [(Ph)Sn(HL)]·MeOH () and [(Me)Sn(HL)(OAc)](Me)O () (HL = bis(2-hydroxybenzaldehyde) thiocarbohydrazone and HL = bis(2-acetylpyrazine) thiocarbonohydrazone) have been synthesized and structurally characterized. Growth inhibition assays indicated that both the proligands and the three complexes are capable of showing anticancer activity against the human hepatocellular carcinoma HepG2 cells with HL and complex showing much higher cytotoxic potential. Subsequent toxicity studies on normal QSG7701cells showed that complex has the highest tumor cell selectivity, and its IC value on QSG7701 cells is 8.
View Article and Find Full Text PDFSix new triterpenoids (1-6) and 22 known analogues (7-28), were separated from the aerial parts of Anchusa italica Retz., a traditional Uygur medicine for treating cardiovascular and cerebrovascular diseases in the Xinjiang region, China. The possible effects of compounds 1-28 on hypoxia/reoxygenation (H/R) induced cardiomyocytes injury were assayed, and compounds 4, 6-17, 21-22 and 26-28 showed significant protective effects.
View Article and Find Full Text PDFFour metal complexes based on 2-benzoylpyridine ,-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 . Interestingly, most of the compounds were found to be selective against hepatocellular carcinoma (HepG2) cells but had little effect on normal hepatocyte (QSG7701) cells.
View Article and Find Full Text PDFIn this paper, synthesis and characterization of metal complexes [Cu(L)]ClO (), [Ga(L)]NO·2HO () and [In(L)]NO·HO () (HL = 2-acetylpyridine (4)-phenylthiosemicarbazone) was carried out, including elemental analysis, spectral analysis (IR, UV-vis, NMR), and X-ray crystallography. Complex contains one S-bridged binuclear [Cu(L)] unit, where two Cu atoms display diverse coordination geometries: one being square planar geometry and the other octahedral geometry. Both and are mononuclear complexes, and the metal centers in and are chelated by two NNS tridentate ligands possessing a distorted octahedral geometry.
View Article and Find Full Text PDFWe 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.
View Article and Find Full Text PDFCip1-interacting zinc-finger protein1 (Ciz1) is a nuclear matrix protein associated DNA replication factor which has been implicated in breast and lung cancer progression. However, the clinical significance of Ciz1 expression in colon cancer has not been determined. This study aimed to examine Ciz1 expression pattern and its potential as a biomarker of prognosis in colon cancer.
View Article and Find Full Text PDFUp 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, (1)H 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.
View Article and Find Full Text PDFUp to now, bismuth(III) complexes with thiosemicarbazones have been comparatively rare. Few in vivo biological studies have been carried out in comparison to the plentiful in vitro data. Here, an interesting nine-coordinated bismuth(III) complex, [Bi(H2L)(NO3)2]NO3 [1; H2L = 2,6-diacetylpyridine bis((4)N-methylthiosemicarbazone)], has been synthesized and structurally characterized.
View Article and Find Full Text PDFZhonghua Wei Chang Wai Ke Za Zhi
July 2012
Purpose: Downregulation of metallothionein (MT) genes has been reported in several tumors with discrepant results. This study is to investigate molecular mechanism of MT gene regulation in colon cancer which is characterized by tumor suppressor gene alterations.
Experimental Design: Integral analysis of microarray data with loss of heterozygosity (LOH) information was employed.
Two metal complexes formulated as [Zn(L)(2)](2)·H(2)O (1) and [Bi(L)(NO(3))(2)(CH(3)OH)] (2), where HL=2-acetylpyrazine N(4)-phenylthiosemicarbazone, have been synthesized and characterized by elemental analysis, IR, MS, NMR and single-crystal X-ray diffraction studies. Biological studies, carried out in vitro against selected bacteria and the K562 leukemia cell lines, respectively, have shown that the free ligand and its two complexes may be endowed with important biological properties, especially HL with MIC=3.90 μg/mL against Pseudomonas aeruginosa, the zinc(II) complex 1 with IC(50)=1.
View Article and Find Full Text PDFTwo 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.
View Article and Find Full Text PDF4-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.
View Article and Find Full Text PDFIn the title salt, (C(6)H(8)N(4))[Mn(C(14)H(8)O(4))(2)(C(6)H(6)N(4))(2)]·6H(2)O, the Mn(II) atom lies on an inversion centre and is coordinated by four N atoms from two 2,2'-biimidazole (biim) ligands and two O atoms from two biphenyl-2,4'-dicarboxylate (bpdc) anions to give a slightly distorted octahedral coordination, while the cation lies about another inversion centre. Adjacent [Mn(bpdc)(2)(biim)(2)](2-) anions are linked via two pairs of N-H..
View Article and Find Full Text PDFActa Crystallogr C
October 2010
The asymmetric unit of the title two-dimensional coordination polymer, [Co(2)(C(16)H(6)O(8))(C(14)H(14)N(4))(2)](n), contains one Co(2+) ion, half of a biphenyl-3,3',4,4'-tetracarboxylate (bptc) anion lying about an inversion centre and one 1,4-bis(imidazol-1-ylmethyl)benzene (bix) ligand. The Co(II) atom is coordinated by three carboxylate O atoms from two different bptc ligands and two N atoms from two bix ligands constructing a distorted square pyramid. Each Co(2+) ion is interlinked by two bptc anions, while each bptc anion coordinates to four Co atoms as a hexadentate ligand so that four Co(II) atoms and four bptc anions afford a larger 38-membered ring.
View Article and Find Full Text PDFTransition 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.
View Article and Find Full Text PDFA series of thiosemicarbazone ligands, HL(1) (2-acetylpyrazine thiosemicarbazone), HL(2) (2-acetylpyrazine N(4)-methylthiosemicarbazone), HL(3) (2-benzoylpyridine thiosemicarbazone) and HL(4) (2-benzoylpyridine N(4)-methylthiosemicarbazone), have been synthesized. The crystal structure of HL(1) has been determined by single-crystal X-ray diffraction. Hydrogen bonds link the different components to stabilize the crystal structure.
View Article and Find Full Text PDFActa Crystallogr Sect E Struct Rep Online
December 2007
The title compound, C(8)H(11)N(5)S, has been prepared by the reaction of 2-acetyl-pyrazine with 4-methyl-3-thio-semi-carbazide. It exists in the thione form and adopts the E configuration. The mol-ecules are connected by the inter-molecular N-H⋯N and N-H⋯S inter-actions.
View Article and Find Full Text PDFThe title complex, [Fe(C(5)H(5))(C(13)H(11)N(2)O(3))], was prepared via self-assembly using ferrocenyl hydrazide and ethyl salicylate. The compound is potentially a tridentate ferrocene-based ligand. The conformation of the mol-ecule allows the formation of an intra-molecular N-H⋯O hydrogen bond involving the hydroxyl group.
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