A new complex C(18)H(24)CoF6N(12)Si has been synthesized by the reaction of cobalt(II) fluoride tetrahydrate with imidazole in a glass vessel. SiF62-was generated by in situ reaction of fluoride on silica. Thi...A new complex C(18)H(24)CoF6N(12)Si has been synthesized by the reaction of cobalt(II) fluoride tetrahydrate with imidazole in a glass vessel. SiF62-was generated by in situ reaction of fluoride on silica. This complex has been characterized by different techniques such as elemental analysis, IR studies, magnetic measurements, electronic absorption measurements and single-crystal X-ray structure determination. The crystals are hexagonal in the R-3 space group, with a = 13.225(6), b = 13.225(6), c = 12.517(11) A, and g = 120°. In complex [Co(im)6]SiF6, the cobalt atom is six-coordinated to adopt a regular octahedral geometry and the SiF62-ion acts as the counter anion. The crystal displays a network structure and SiF62- bridging hexagram formation by N-(39)···F-Si interactions between imdazole and SiF62-. SiF62-plays an important role in assembling the supramolecular aggregates.展开更多
Objective To explore the protective effects of N Acetylcysteine (NAC) on exogenous hydrogen peroxide and endogenous superoxide anion induced DNA strand breakage in human spermatozoa by using the single cell gel el...Objective To explore the protective effects of N Acetylcysteine (NAC) on exogenous hydrogen peroxide and endogenous superoxide anion induced DNA strand breakage in human spermatozoa by using the single cell gel electropherosis (SCGE) Methods Sperm cells were exposed to 0.5 mmol/L of H 2O 2 or 5.0 mmol/L of β NADPH with or without 0.1, 0.5, 1.0 mmol/L of NAC. The percentage of sperm comet cells and the comet tail lengths were measured in the treated sperm cells by using SCGE. Results Both percentage of comet sperm nuclei and mean tail length in sperm cells exposed to 0.5 mmol/L hydrogen peroxide with different concentrations of NAC decrease significantly in a dose dependent manner as compared with sperm cells exposed to H 2O 2 without NAC or catalase. Although mean tail length in sperm cells exposed to 5.0 mmol/L of β NADPH with different concentrations of NAC decreases significantly compared with sperm cells exposed to β NADPH without NAC or SOD, there were no significant differences on the percentage of sperm comet cells between sperm cells exposed to 5.0 mmol/L of β NADPH with different concentrations of NAC and sperm cells exposed to 5.0 mmol/L of β NADPH without NAC. Conclusion NAC has a protective effect on exogenous hydrogen peroxide induced DNA damage, while protective effect of NAC against O - 2 induced DNA strand breakage is significant but very weak.展开更多
Fifteen novel 2-(3-oxobenzo[d]isothiazol-2(3H)-yl)ethyl benzoates were synthesi- zed by the condensation of 2-(2-hydroxyethyl)benzo[d]isothiazol-3(2H)-one with substituted benzoic acids in dichloromethane. All...Fifteen novel 2-(3-oxobenzo[d]isothiazol-2(3H)-yl)ethyl benzoates were synthesi- zed by the condensation of 2-(2-hydroxyethyl)benzo[d]isothiazol-3(2H)-one with substituted benzoic acids in dichloromethane. All the compounds were characterized by elemental analysis, IR, ESI-MS and 1H NMR. The crystal structures for 2-(2-hydroxyethyl)benzo[d]isothiazol-3(2H)-one (2) and 2-(3-oxobenzo[d]isothiazol-2(3H)-yl)ethyl 2-methoxybenzoate (30) have been determined by X-ray crystal structure analysis. Compound 2 (C9H9NO2S) crystallizes in the monoclinic system, space group Pn with a = 10.552(3), b = 7.849(2), c = 10.765(4) A, β = 103.128(4)°, V= 868.3(5) A3, Mr = 195.24, Dc = 1.493 Mg.m-3, μ = 0.33 mm-1, F(000) = 408, Z = 4, R= 0.0314 and wR= 0.0628. Compound 30 (C17H15NO4S) crystallizes in the triclinic system, space group P1 with a = 8.028(2), b = 9.300(2), c = 10.430(3)A, V= 752.1(3)A3, Mr = 329.36, D,= 1.454 Mg.m-3, p = 0.24 mm-1, F(000) = 344, Z = 2, R = 0.0377 and wR = 0.0904. The preliminary biological test indicated that the title compounds show better growth inhibitory activity against the gram-positive bacteria than the gram-negative bacteria.展开更多
The reaction of anhydrous cobalt(II) dichloride with 1-methylimidazoline-2(3H)- thione in dichloromethane solution gave the title complex, [Co(C4H6N2S)2Cl2]. X-ray single-crystal analysis revealed that the complex c...The reaction of anhydrous cobalt(II) dichloride with 1-methylimidazoline-2(3H)- thione in dichloromethane solution gave the title complex, [Co(C4H6N2S)2Cl2]. X-ray single-crystal analysis revealed that the complex crystallizes in a monoclinic system, space group P21/c, a = 13.9707(10), b = 10.0435(7), c = 10.3910(6) ?, β = 91.181(3)o, V = 1457.70(17) ?3, Z = 4, C8H12Cl2N4S2Co, Mr = 358.17, Dc = 1.632 g/cm3, μ = 1.813 mm–1, F(000) = 724, the final R = 0.0710 and wR = 0.1224 for 1549 observed reflections with I > 2σ(I). The Co atom is coordinated by two S atoms from two 1-methylimidazoline-2(3H)-thione ligands and two chloride ions in a slightly distorted tetrahedral geometry. The intramolecular classical hydrogen-bonding interactions involving chloride ions and N–H groups of the heterocyclic thione ligands are observed. The offset π-π stacking interactions between the imidazole rings of adjacent molecules with a face-to-face dis- tance of 3.604 ? are found in the packing diagram.展开更多
2-Ureido-4[1H]-pyrimidinone quadruple hydrogen-bonded assembly 1,1 containing N,N-dimethylaminophenyl moiety exhibits a sensitive response to fluoride anion and lead cation. Spectroscopic studies reveal that the prese...2-Ureido-4[1H]-pyrimidinone quadruple hydrogen-bonded assembly 1,1 containing N,N-dimethylaminophenyl moiety exhibits a sensitive response to fluoride anion and lead cation. Spectroscopic studies reveal that the presence of small amount of fluoride anions and lead cations can easily disassemble and intercalate 2-ureido- 4[ 1H]-pyri mi di none hydrogen-bonded supramolecular architectures.展开更多
To evaluate the effect of neutral C–H bond or electron pair of nitrogen atom with sp2hybridization(N(sp2)) involving into the same chemical environment for anion binding, two analogous tetracationic imidazolium m...To evaluate the effect of neutral C–H bond or electron pair of nitrogen atom with sp2hybridization(N(sp2)) involving into the same chemical environment for anion binding, two analogous tetracationic imidazolium macrocycles, namely cyclo[2](2,6-bis-(1H-imidazol-1-yl)pyridine) [2](1,3-dimethylenebenzene)(14+), and cyclo[2](2,6-bis-(1H-imidazol-1-yl)pyridine)[2](2,6-di methylenepyridine)(24+)were studied in detail as small inorganic anion receptors. The guest anions with different shapes are Cl,N3, NO3, and H2PO4. The host–guest interactions were characterized via1 H NMR spectroscopy,electrospray ionization mass spectrometry(ESI-MS) and single crystal X-ray crystallography. The results implied that macrocyclic hosts with similar backbone but two distinct binding sites(14+with neutral C–H vs. 24+with N(sp2)) vary markedly in their response to anions, including the binding modes and association constants. The finding will serve to the construction of new anion receptors, even improve insights into the anion binding process in biology.展开更多
基金financially supported by Higher Education Commission of Pakistan under Indigenous PhD 5000 Fellowship Program and International Research Support Initiative Program(IRSIP)
文摘A new complex C(18)H(24)CoF6N(12)Si has been synthesized by the reaction of cobalt(II) fluoride tetrahydrate with imidazole in a glass vessel. SiF62-was generated by in situ reaction of fluoride on silica. This complex has been characterized by different techniques such as elemental analysis, IR studies, magnetic measurements, electronic absorption measurements and single-crystal X-ray structure determination. The crystals are hexagonal in the R-3 space group, with a = 13.225(6), b = 13.225(6), c = 12.517(11) A, and g = 120°. In complex [Co(im)6]SiF6, the cobalt atom is six-coordinated to adopt a regular octahedral geometry and the SiF62-ion acts as the counter anion. The crystal displays a network structure and SiF62- bridging hexagram formation by N-(39)···F-Si interactions between imdazole and SiF62-. SiF62-plays an important role in assembling the supramolecular aggregates.
基金China Medical Board ( 980 0 1 ) and Natural Science Foundation ofAnhui Province( 99j1 0 0 95)
文摘Objective To explore the protective effects of N Acetylcysteine (NAC) on exogenous hydrogen peroxide and endogenous superoxide anion induced DNA strand breakage in human spermatozoa by using the single cell gel electropherosis (SCGE) Methods Sperm cells were exposed to 0.5 mmol/L of H 2O 2 or 5.0 mmol/L of β NADPH with or without 0.1, 0.5, 1.0 mmol/L of NAC. The percentage of sperm comet cells and the comet tail lengths were measured in the treated sperm cells by using SCGE. Results Both percentage of comet sperm nuclei and mean tail length in sperm cells exposed to 0.5 mmol/L hydrogen peroxide with different concentrations of NAC decrease significantly in a dose dependent manner as compared with sperm cells exposed to H 2O 2 without NAC or catalase. Although mean tail length in sperm cells exposed to 5.0 mmol/L of β NADPH with different concentrations of NAC decreases significantly compared with sperm cells exposed to β NADPH without NAC or SOD, there were no significant differences on the percentage of sperm comet cells between sperm cells exposed to 5.0 mmol/L of β NADPH with different concentrations of NAC and sperm cells exposed to 5.0 mmol/L of β NADPH without NAC. Conclusion NAC has a protective effect on exogenous hydrogen peroxide induced DNA damage, while protective effect of NAC against O - 2 induced DNA strand breakage is significant but very weak.
基金Supported by the National Natural Science Foundation of China (No. 20962007)
文摘Fifteen novel 2-(3-oxobenzo[d]isothiazol-2(3H)-yl)ethyl benzoates were synthesi- zed by the condensation of 2-(2-hydroxyethyl)benzo[d]isothiazol-3(2H)-one with substituted benzoic acids in dichloromethane. All the compounds were characterized by elemental analysis, IR, ESI-MS and 1H NMR. The crystal structures for 2-(2-hydroxyethyl)benzo[d]isothiazol-3(2H)-one (2) and 2-(3-oxobenzo[d]isothiazol-2(3H)-yl)ethyl 2-methoxybenzoate (30) have been determined by X-ray crystal structure analysis. Compound 2 (C9H9NO2S) crystallizes in the monoclinic system, space group Pn with a = 10.552(3), b = 7.849(2), c = 10.765(4) A, β = 103.128(4)°, V= 868.3(5) A3, Mr = 195.24, Dc = 1.493 Mg.m-3, μ = 0.33 mm-1, F(000) = 408, Z = 4, R= 0.0314 and wR= 0.0628. Compound 30 (C17H15NO4S) crystallizes in the triclinic system, space group P1 with a = 8.028(2), b = 9.300(2), c = 10.430(3)A, V= 752.1(3)A3, Mr = 329.36, D,= 1.454 Mg.m-3, p = 0.24 mm-1, F(000) = 344, Z = 2, R = 0.0377 and wR = 0.0904. The preliminary biological test indicated that the title compounds show better growth inhibitory activity against the gram-positive bacteria than the gram-negative bacteria.
基金Supported by the National Natural Science Foundation of China (20325106 20333070)and the "One-hundred Talent" Project from the Chinese Academy of Sciences
文摘The reaction of anhydrous cobalt(II) dichloride with 1-methylimidazoline-2(3H)- thione in dichloromethane solution gave the title complex, [Co(C4H6N2S)2Cl2]. X-ray single-crystal analysis revealed that the complex crystallizes in a monoclinic system, space group P21/c, a = 13.9707(10), b = 10.0435(7), c = 10.3910(6) ?, β = 91.181(3)o, V = 1457.70(17) ?3, Z = 4, C8H12Cl2N4S2Co, Mr = 358.17, Dc = 1.632 g/cm3, μ = 1.813 mm–1, F(000) = 724, the final R = 0.0710 and wR = 0.1224 for 1549 observed reflections with I > 2σ(I). The Co atom is coordinated by two S atoms from two 1-methylimidazoline-2(3H)-thione ligands and two chloride ions in a slightly distorted tetrahedral geometry. The intramolecular classical hydrogen-bonding interactions involving chloride ions and N–H groups of the heterocyclic thione ligands are observed. The offset π-π stacking interactions between the imidazole rings of adjacent molecules with a face-to-face dis- tance of 3.604 ? are found in the packing diagram.
基金Project supported by the National Natural Science Foundation of China (Nos. 20732007, 21002108 and 91024041), the Ministry of Science and Technology of China (Nos. 2007CB808004, 2007CB936001). and the Bureau for Basic Research of the Chinese Academy of Sciences.
文摘2-Ureido-4[1H]-pyrimidinone quadruple hydrogen-bonded assembly 1,1 containing N,N-dimethylaminophenyl moiety exhibits a sensitive response to fluoride anion and lead cation. Spectroscopic studies reveal that the presence of small amount of fluoride anions and lead cations can easily disassemble and intercalate 2-ureido- 4[ 1H]-pyri mi di none hydrogen-bonded supramolecular architectures.
基金financially supported by the National Natural Science Foundation of China (No. 21202199 to Han-Yuan Gong, and No. 21372258 to Li-Jin Xu)
文摘To evaluate the effect of neutral C–H bond or electron pair of nitrogen atom with sp2hybridization(N(sp2)) involving into the same chemical environment for anion binding, two analogous tetracationic imidazolium macrocycles, namely cyclo[2](2,6-bis-(1H-imidazol-1-yl)pyridine) [2](1,3-dimethylenebenzene)(14+), and cyclo[2](2,6-bis-(1H-imidazol-1-yl)pyridine)[2](2,6-di methylenepyridine)(24+)were studied in detail as small inorganic anion receptors. The guest anions with different shapes are Cl,N3, NO3, and H2PO4. The host–guest interactions were characterized via1 H NMR spectroscopy,electrospray ionization mass spectrometry(ESI-MS) and single crystal X-ray crystallography. The results implied that macrocyclic hosts with similar backbone but two distinct binding sites(14+with neutral C–H vs. 24+with N(sp2)) vary markedly in their response to anions, including the binding modes and association constants. The finding will serve to the construction of new anion receptors, even improve insights into the anion binding process in biology.