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利用Mn^2+,Ba^2+及Sr^2+作为模板离子,合成了一类新型的含呋喃环系 Schiff碱型大环化合物,如L^1和配合物L^2Ba(ClO4)2,L^3Ba(ClO4)2和L^4Ba (ClO4)2.L^2-L^4的Ba^2+配合物经与NaSO4水溶液反应解络,得到自由配体L^2, L^3和L^4,配体L^2和L^3分别与Sr^2+作用,得到配合物L^2Sr(ClO4)2和L^3Sr (ClO4)2。上述大环配体和各种配合物均经元素分析,IR,^1H NMR,MS等证实了它 们的结构和组成。 相似文献
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1I7NTRODUCT1ONAsequenceofnovelhydroxylmesocyclicdiaminesLl-3Jweresynthesizedinourlaboratoryandemployedtobindtransitionmetalions.Wehavepreviouslyreported[']thatoneofthesemesocycles,3-hydroxyL1,5-diazacycloheptane,adoptstranschair-chairconformationinthecomplexes,whereasitlookslikeacrownintheabsenceofguests.Here,wereportthemolecularstructureofthetitlemesocyclicdiaminewhichbearsdoublehydroxylgroups.2EXPERIMENTALThetitlecompound['Jwasheatedtobedissolvedinalittlewater,followedbyad-ditiono… 相似文献
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In this paper, perhydroxyl-cucurbit[6]uril ((HO)12CB[6]) was, for the first time, grafted to silica gel as a hydrophilic-interaction chromatographic stationary phase. Several alkaloids were used as probes to investigate the retention mechanism on the new stationary phase. The effect of mobile phase variables such as acetonitrile content, ionic strength and pH on their chromatographic behavior was investigated. The results indicate that the stationary phase behaves as a hydrophilic-interaction chromatographic packing. Finally, several alkaloids were separated on the stationary phase. 相似文献
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This paper describes a matrix-free method for performing desorption/ionization directly from mesoporous nanocrystalline titania sol-gel thin films, which have good absorption capacity in the ultraviolet (UV) range and can act as assisting materials during UV matrix-assisted laser desorption/ionization mass spectrometric (MALDI-MS) analysis. A high concentration of citrate buffer was added into this system to provide the proton source and to reduce the presence of alkali cation adducts of the analytes. The analyte signals appear uniformly over the whole sample deposition area. Protonated molecules (MH(+) ions) of analytes dominate the titania MALDI mass spectra. Surfactants, peptides, tryptic digest products, and small proteins with molecular weights below ca. 24 000 Da, are observed in the titania MALDI mass spectra. Detection limits for insulin are as low as ca. 2 fmol with mass resolution of ca. 660. 相似文献
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The crystal structure of a. Ni(II) complex with 1,7-diaminoethyl-4,10-dimethyl-1,4,7,10-tetraazacyclododecane has been determined by X-ray diffraction method. Crystal data for NiC14H38Br2N6O: monoclinic, space group P21/n, a=0.8848(3), b=1.4656(3), c=1.5828(3) nm, β=90.47(3)°, V=2.0525 nm3, Z=4. The two pendant primary amino groups are located in cis positions in the complex, "their nitrogen atoms and the four nitrogen donors of the foled tetraaza-macrocycle coordinate Ni(II) ion, forming a distorted octahedral geometry. 相似文献
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This paper deals with the synthesis of a new lateral macrobicyclic cryptand 10. Condensation of 2.6-di(bromomethyl)pyridine with 3-(n-tosylamino) methyl propionate in the presence of anhydrous K2CO3 at room temperature gave 5 which was hydrolyzed to 6. Reaction of the latter with excess sulfonyl chloride afforded 2,6-di(4′-chloroformyl-2′-tosyl-2′-azabutyl)pyridine (7). Pentaaza-1,5,13,17,28-dithia-20,25-tricyclo [15,5,5,17,11]-octacosa-7,9,11 (28)-triene(10) has been synthesized by the following sequence of reactions: Condensation of 7 with 1,7-diaza-4,10-dithia-dodecane (3) by high dilution technique in toluene-THF at room temperature afforded 8 which was reduced by diborane in THF solution to give 9. Treatment of 9 with sodium anthracene in monoglyme produced 10. 相似文献
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吲跺啉螺吡喃是一类重要的有机光致变色化合物,当被紫外光和可见光照射时可逆地异构化.一系列的研究表明它在非银材料、非线性光学器件以及高分辨率的信息存贮和再现等诸方面的应用价值[1].90年代以来,Inouye[2,3],Kimura[4-6]和吴成泰等[7-9]曾将冠醚结构单元引入螺吡喃,研究了对碱金属离子的识别作用及其由此诱导含冠醚螺吡喃化合物的异构化现象.由于冠醚化合物对金属离子具有特定的络合作用,当在含冠醚螺吡喃化合物中加入某些金属离子时,能诱发螺吡喃结构的异构化,从而强烈地影响异构化平衡,… 相似文献