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1.
Fourteen new derivatives of avermectin B1a, and ivermectin B1a were synthesized from C5-O-triphenyl silylavermectin B1a and ivermectin B1a (yield from 40% to 83%). Their chemical structures were characterized by means of IR. ^1H NMR, ^13C NMR and FAB-MS spectrometries. Some of them show excellent insecticidal activity.  相似文献   

2.
Recently, the increasing demand for effective treatment of cardiovascular diseases (CD), such as hypertension, heart failure, hypercholesterolemia, atherosclerosis, is becoming urgent task. The researches in therapeutics for CD focus on the modification o…  相似文献   

3.
The compound Ba4Fe2I5S4 has been prepared at 1223-1123 K by the "U-assisted" reaction of FeS, BaS, S, and U with BaI2 as a flux. A more rational synthesis was also found; however, the presence of U appears to be essential for the formation of single crystals suitable for X-ray diffraction studies. Ba4Fe2I5S4 crystallizes in a new structure type with two formula units in space group I4/m of the tetragonal system. The structure consists of a Ba-I network penetrated by (1)infinity[Fe2S4] chains. Each Fe atom, which is located on a site with 4 symmetry, is tetrahedrally coordinated to four S atoms. The FeS4 tetrahedra edge-share to form linear (1)infinity[Fe2S4] chains in the [001] direction. The Fe-Fe interatomic distance in these chains is 2.5630(4) A, only about 3% longer than the shortest Fe-Fe distance in -Fe metal. Charge balance dictates that the average formal oxidation state of Fe in these chains is +2.5. The M?ssbauer spectra obtained at 85 and 270 K comprise a single quadrupole doublet that has hyperfine parameters consistent with an average Fe oxidation state of +2.5. The M?ssbauer spectrum obtained at 4.2 K consists of a single magnetic sextet with a small hyperfine field of -15.5 T. This spectrum is also consistent with rapid electron delocalization and an average Fe oxidation state of +2.5. The molar magnetic susceptibility of Ba4Fe2I5S4, obtained between 3.4 and 300 K, qualitatively indicates the presence of weak pseudo-one-dimensional ferromagnetic exchange within a linear chain above 100 K and weak three-dimensional ordering between the chains at lower temperatures.  相似文献   

4.
1-Substituted- 4-trimethylsilylcyclohex- 3-enol and 1-substituted- 4-trimetnylsilyl-cyclohexanol, 4-trimethylsilylcyclohex-3-enol and 4-trimethylsilylcyclohexanol, and some of their esters and carbon counterparts were synthesized. Structures of the nineteen new compounds were determined by 1H NMR, IR and MS. Their odors are evaluated.  相似文献   

5.
The medium was modified in the synthesis of the isochroman-4-one.Twenty-one of isochroman-4-one derivatives were synthesized.Among those there were five o-acyl oximes,six mannich bases,four 3-methylene substituted compounds and six pyrimidino and pyrazolo derivatives of isochroman-4-one.Part of the Mannich bases of isochromanone in animal indication was tested  相似文献   

6.
Three lanthanide(III) complexes [Ln(4-NCP)(1,4-BDC)]n·xn H2O(Ln = Pr(1), Sm(2), Nd(3). 4-HNCP = 2-(4-carboxyphenyl)imidazo(4,5-f)(1,10)phenanthroline, 1,4-H2 BDC = benzene-1,4-dicarboxylic acid) have been hydrothermally synthesized and characterized via elemental analysis, infrared spectrometry and single-crystal X-ray diffraction. Structural analyses revealed that complexes 1~3 possess similar porous three-dimensional frameworks with the point symbol {4~(12)·6~3}. Meanwhile, complexes 1~3 exhibit excellent thermal stabilities and complex 2 exhibits characteristic luminescent property.  相似文献   

7.
Chromium (Ⅲ) has been implicated as glucose tolerance factor (GTF) in the maintenance of normal lipid and carbohydrate metabolism[1]. Several organic chromium (Ⅲ) complexes containing nicotinate, amino acids ligand which have much higher biological activity than chromic chloride have been synthesized and extensively studied[2]. Tripicolinatechromium (Ⅲ) as a new human chromium(Ⅲ) nutritional supplement was shown to reduce the symptoms of diabetes, hyperglycemia and cholesterol significantly[3]. Although the crystal structure and NMR spectrum of tripicolinatechromium (Ⅲ) was studied previously[4,5], Its properties have only received little attention. In this paper, we report the studies of syntheses and properties of tripicolinatechromium(Ⅲ).  相似文献   

8.
Constellation Technology Corporation has developed a spectroscopic nuclear detector called the Xe-110 that is well suited for downhole use in oil and gas well logging. The advantages possessed by this detector over traditional technologies such as NaI(Tl) scintillators are summarized. We discuss an analysis of gamma-ray spectra taken by the Xe-110, which suggests that the superior energy resolution and low background level of this detector enables identification of important features in neutron activation spectra of hydrocarbons that might not be identifiable using an NaI(Tl) crystal.  相似文献   

9.
Russian Journal of Organic Chemistry - One-pot three-component synthesis of 1H-imidazol-5(4H)-one derivatives from (Z)-4-(aryl­methylidene)-2-methyl-1,3-oxazol-5(4H)-one, methylamine, and...  相似文献   

10.
Acylthiourea derivatives are useful as pesticides, herbicides, fungicides and regulator for plant growth, and also as important intermediates in the organic synthesis. In recent years, phase transfer catalysis reaction technique has been widely recognized as an efficient synthetic tool and attracted much attention. In view of these observations, a series of 5-aryl-2-furoyl thioureas containing substituted pyrimidine ring were synthesized using PEG-400 as solid-liquid phase transfer catalyst under ultrasonic irradiation. All of the new compounds have been exactly determined by IR, 1H NMRand elemental analysis.  相似文献   

11.
A new Sr(Ⅱ) complex, [Sr(Hsip)(H2O)](1, NaH2sip = 5-sulfoisophthalic acid monosodium), has been synthesized by solvothermal reaction of Sr CO3 and NaH2sip at 120 ℃, and characterized by single-crystal X-ray diffraction studies, elemental analysis and FT-IR. Singlecrystal X-ray diffraction reveals that compound 1 has a 3D architecture, and there is only one crystallographically independent Sr(Ⅱ) ion in 1. The coordination geometry of Sr(Ⅱ) is a distorted tetragonal anti-prism. The whole Hsip2- ligand performs a μ6-coordination model. In the solid state, complex 1 shows luminescence with the maximum emission intensity at 417 nm upon excitation at 320 nm. Thermal stability of complex 1 was also investigated.  相似文献   

12.
Introduction Metal thiolato complexes have been extensively investigated because of their ability to adopt various nuclearities and their relevance in biological science, since they form the inorganic part of the biologically active centers of some metalloproteins and enzymes.1-3 Recently, attention has been paid to the coordination chemistry of heterocyclic thiol/thione donors, which can give potential access to new compounds with unusual structures and reactivities,4 such as 2-mercaptobenzo-…  相似文献   

13.
The title compound, C15H22N3O9P·2H2O, Mr=455.36, crystallizes in orthorhombic, space group P212121, with a =9.193(2), b =14.681(3), c =15.201(3)A, V =2501(1)A3, Z =4, Dx=1.474g/cm3, λ(MoKα)=0.71073A, μ=0.1894mm-1, T=299±1K, F(000)=960, R=0.061 and Rw=0.068 for 1899 observed reflections with I≥3σ(I). The analysis results indicate that the title compound is of lyxo-configuration and the configuration at C4″ is S. In the crystal state the molecule has anti conformation about glycosidic bond with the torsion angle-151.7°, the sugar ring is puckered with C3′-endo-C2′-exo, and the conformation of the C4′-C5′ bond is-sc.  相似文献   

14.
The Diels-Alder adduct (±)-5 of furan to 1-cyanovinyl acetate was converted to (1RS,2RS,6RS,7SR,8SR,10RS)-10-{[(tert-butyl)dimethylsilyl]-oxy}-4-ethoxy (1) and -4-phenyl-3,9,11-trioxa-5-azatetracyclo[5.3.1.02,6.08,10]-undec-4-ene (2). These compounds reacted with TiCl4 to afford stable (1RS,2RS,6RS,7SR,8SR,9SR)-9-{[(tert-butyl)dimethylsilyl]oxy}-9-chloro-4-ethoxy-3,10-dioxa-5-azatricyclo[5.2.1.02,6]decan-8-ol (3) and (1RS,2RS,6RS,7SR,8SR,9SR)-9-{[(tert-butyl)dimethylsilyl]oxy}-9-chloro-4-phenyl-3,10-dioxa-5-azatricyclo[5.2.1.02,6]decan-8-ol (4), respectively.  相似文献   

15.
Complexes[Zn(pbm)(5-hip)3](1),[Zn(pbm)(5-nip)3](2),[Mn(pbm)(H3btc)2(H2O)](3)and[Mn(pbm)(5-nip)3](4),where H2HIPA=5-hydroxyisophthalic acid,H2nip=5-nitroisophtha...  相似文献   

16.
Reaction of [(η 5-C5Me5)M(μ-Cl)Cl]2 {M?=?Rh (1), Ir (2)} and [(η 5-C5Me5)MCl2(DBT)] (DBT?=?dibenzothiophene) {M?=?Rh (3), Ir (4)} with polypyridyl ligands 2,3-bis(2-pyridyl)pyrazine (bpp), 2,3-bis(2-pyridyl)quinoxaline (bpq), 1,3,5-tris(2-pyridyl)-2,4,6-triazine (tptz), 2,3,5,6-tetrakis(2-pyridyl)pyrazine (tppz) and 4′-pyridyl-2,2′:6′,2′′-terpyridine (py-terpy) results in the formation of mononuclear cationic complexes, [(η 5-C5Me5)MCl(poly-py)]+ (poly-py?=?polypyridyl ligand). The complexes were isolated as hexafluorophosphate salts and characterized by IR and NMR spectroscopy.  相似文献   

17.
The Zr-H bond of zirconocene hydridochloride was heterolyzed at room temperature by five compounds containing nitrogen and hydroxyl group to give Cp(Q)2ZrCl(1) (Cp = cyclopentadienyl and Q = 8-quinolinoyl ) , Cp (Q-Me )2ZrCl (2) , Cp(5,7-Br2Q)2ZrCl(3), Cp2(2-pyridoyl)ZrCl(4) , and Cp(2-aminoethanoyl)2ZrCl(5), which were characterized by elemental analysis, IR, and 1H NMR spectroscopy. The molecular structure of 1 was confirmed by X-ray diffraction determination. The crystal of 1 crystallized monoclinically, space group P21/n a= 0.9004(2), b=1.3961(2), c = 1. 6056(2) nm, β=99. 48(1)°? V=1. 9906 nm3, Z = 4, and Dc=1. 582 g/cm3. The coordination polyhedron around the Zr atom can be described as a distorted octahedron. The Zr-N bonds of 0. 2364(3) and 0. 2377(4) nm suggest that they are coordination bonds. The two planar 8-quinolinoyl groups as bidentate ligands chelate with Zr atom, forming a dihedral angle of 108. 4(1)°?  相似文献   

18.
Zn(Ⅱ), Ni(Ⅱ) and Co(Ⅱ) compounds(1~3) based on 2-(2-pyridyl)benzothiazole(bpt) and terephthalic acid(PTA) were synthesized. The crystal structures of [Zn(bpt)(PTA)2](1), [Ni(bpt)(PTA)2](2), and [Co(bpt)(PTA)2](3) have been determined by single-crystal X-ray diffraction analysis, which shows that all the three complexes belong to monoclinic system with space group P21/c. Time-dependent density functional theory(TD-DFT) calculation is performed on a reference structure of compound 3. The excited electrons mainly localized at the π* of ligand 2-(2-pyridyl)benzothiazole, which will be convenient for them to bind with the DNA reacting sites. Fluorescence spectroscopy, ultraviolet(UV) spectroscopy and viscosity were used to characterize the interaction of the compounds with Calf thymus DNA(CT-DNA). The results indicate that compounds 1~3 bind to CT-DNA and have a strong interaction with DNA. The compounds can probably bind to CT-DNA via a non-intercalative mode as concluded by studying the viscosity of a DNA solution in the presence of the compounds. This combination can effectively break DNA, which speculates that these three compounds may interact with the cancer cell DNA in this binding mode, thereby damaging the cancer cells.  相似文献   

19.
IntroductionThestudyofmagneticexchangeinteractionbetweenparamagneticcenterspropagatedbymulti-atombridgesisofcurrentinterestduetounderstandingthepathwayofelectrontransferinbio1ogicalsystemandobtainingsomeusefulin-formationaboutdesigningmolecule-basedmagnets.Manypapers['-'Jdealingwithphthalato,isophthalatoandterephthalatoligandsasamulti-atombridgeshavebeenpublished.1thasbeenrevealedbythevariable-temperaturemagneticsusceptibilityinvestigationthatlong-rangemagneticcouplingoccursbetweentwoparamagne…  相似文献   

20.
The title compounds 5-chloro-3-methyl-1-phenyl-1H-pyrazole-4-carboxylic acid(C11H9Cl N2O2, HL)(1) and [Cu(L)2(H2O)](2) were prepared and structurally characterized by elemental analysis, IR and single-crystal X-ray diffraction. Compound 1(C11H9Cl N2O2) crystallizes in the monoclinic system, space group P21/n with a = 7.249(3), b = 20.515(10), c = 7.249(3),β= 96.30°, V = 1071.6(9) ?3, Z = 4, Mr = 236.65, Dc = 1.467 g/cm3, F(000) = 488, GOOF = 1.029, μ= 0.341 mm-1, the final R = 0.0736 and w R = 0.1966 for 1500 observed reflections with I 2σ(I). Compound 2(C22H18Cl2Cu N4O5) crystallizes in the monoclinic system, space group P21/c with a = 7.2931(6), b = 24.548(2), c = 13.2726(11), β= 99.4040(10)°, V = 2344.2(3) ?3, Z = 4, Mr = 552.84, Dc = 1.566 g/cm3, F(000) = 1124, GOOF = 1.050, μ= 1.201 mm-1, the final R = 0.0376 and w R = 0.1000 for 3626 observed reflections with I 2σ(I). 1 and 2 are connected through hydrogen bonding interactions to generate 2D and 3D supramolecular structures, respectively. Moreover, the preliminary antibacterial activities of 1 and 2 against the gram positive bacteria(S. aureus, C. albicans and B. subtilis) and gram negative bacteria(E. coli and P. aeruginosa) have been tested by using the microdilution method, and the results indicate that 2 is more active than 1 against the tested bacteria.  相似文献   

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