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1.
1INTRODUCTIONThepyrazolo[3,4-b]pyridineclassofcompoundspossessmanybiologicalandpharmacologicalactivi-ties[1],suchasactiveanti-concretionmedicaments[2]aswellasactiveanti-gramnegativeandpositivebacteriaagents[3].Thereforethesynthesesofsuchcompoundshavearousedgreatattentionofalargenumberofchemists.Themostimportantsyntheticrouteisthecondensationreaction[4~11]ofamino-pyrazoleandα,β-unsaturatedcompounds.Theorganicreactionundermicrowaveirradia-tionhastheadvantagesoffastreactionspeed,shorttime…  相似文献   

2.
β,β-二烷硫基-α,β-不饱和酮类化合物作为一类具多反应中心的活泼中间体在有机合成中的应用,近20年来已引人注目并进行了深入广泛的研究~[1,2].以往的研究大多是针对β,β-二甲硫基-α,β-不饱和酮类化合物1进行的,而对结构相近的β,β-1,3-亚丙二硫基-α,β-不饱和酮类化合物2的研究较少.对于1类的合成,所用碱的选择至关重要~[1].实验证明叔丁醇钠和叔丁醇钾~[3~5]在1类的合成中效果较好.前文~[6]曾以六甲基二硅氨基锂(LHMDS)为碱高  相似文献   

3.
1INTRODUCTIONPolarizedketenedithioacetalshavebeenex-tensivelyusedasbuildingblocksinorganicsyn-thesis,especiallyinthesynthesisofheterocycliccompounds[1~6].Pyrazoleanditsderivativesrepre-sentoneofthemostactiveclassesofcompoundspossessingwidespectraofbiologicalactivities.Overthepastfewyears,considerableevidenceshavebeenaccumulatedtodemonstratetheefficacyofpyrazolederivatives,suchasantibacterial[7],fun-gicidal[8],herbicidal[9],insecticidal[10]andotherbiologicalactivities[11,12].Uptonow,alarg…  相似文献   

4.
1 INTRODUCTIONInourinvestigationofhemithioacetals,wediscoveredthatα-benzoylhemithioac-etalisquitestableandhastwoelectrophilicsitesthatcanreactwithalkylureastoformahydantoinring[1].Althoughthehydantoinringitselfdoesnotpresentanymedicinalactivity,somedisubstitutedhydantoinshavebeenwidelyusedasmedicineforitsregulareffectonthebioelectricactivityofthenervoussystem.Inordertoim-proveandexpandtheactivityaswellastopreventsideeffects,variouskindsofhy-dantoinderivativeshavebeenpreparedandtested[2].…  相似文献   

5.
二氢嘧啶酮(DHPMs)及其衍生物具有广泛的生物活性,如抗病毒、抗肿瘤、抗癌、抗高血压及消炎等作用[1].此外,DHPMs及其衍生物作为钙通道阻滞剂、α1a-对抗剂和神经肽Y的对抗剂,显示出良好的药理活性[2].更重要的是,最近几种含二氢嘧啶酮-5-羧酸盐的海洋生物碱被成功分离出来,并表现出重要的生物学性质[3],某些可以阻止HIVgp-120-CD4键的形成,是一种潜在的HIV抑制剂[4].因此,对DHPMs及其衍生物的研究成为生物活性有机杂环化合物的研究热点之一.  相似文献   

6.
1 INTRODUCTION The design, development and marketing of new chiral drugs are now a major theme in the drug chirality research and industry[1]. In 1996, the FDA announced it would consider further incentives for developing single isomer drugs because of their bet- ter pharmacokinetics prosperity, safety, and tolera- bility. Our recent drug candidate, 9α-(3-azabicyclo- [3,3,1]nonanyl)-2?-cyclopentyl-2?-hydroxyl-2?-thien- ylacetate I, is a potential selective M1 antagonist. It is composed…  相似文献   

7.
《结构化学》2004,23(4):358-360
1INTRODUCTION4H-Chromeneisaconstructionunitofsomenaturalproducts.4H-Chromeneswithaminoandcyanogroupsarealsosynthonofsomespecialnaturalproducts[1,2].Thesubstituted4H-chromenespossessawiderangeofpharmacologicalactivi-ties[3~5].Inordertoinvestigatetheactivi…  相似文献   

8.
1INTRODUCTIONResorcin[4]arenesarecavity-shapedmacro-cycleswhichcanbeeasilysynthesizedfromresor-cinolandaldehydesinthepresenceofacidiccataly-sis[1].Theyareattachedmuchinterestinthefieldofsupramolecularchemistryasartificialreceptorsandstartingmaterialsforthepreparationofmoresophis-ticatedmolecules[2].Duetotheirstructuralfeaturestheyplayanimportantroleashostmoleculesforavarietyofneutralandchargedguestcompounds[3].Theresorcin[4]arenesusuallyadoptfourdifferentcon-formers,crown(rccc,C4),boat(rc…  相似文献   

9.
在水热条件下,以Na10[A-α-SiW9O34].18H2O、氯化铜、四氮唑乙酸和1,2-丙二胺为原料合成了一种三维有机-无机杂化单铜取代Keggin型硅钨酸盐[Cu(dap)2(H2O)][Cu(dap)2][Na(H2O)5]H[α-SiW11CuO39].H2O(1),并借助元素分析、红外光谱和单晶X射线衍射对其进行了表征.结果表明,化合物1的分子结构片段由1个单铜取代Keggin型多金属氧酸盐单元[α-SiW11CuO39]6-,1个支撑的[Cu(dap)2(H2O)]2+配离子,1个[Cu(dap)2(H2O)]2+桥配离子,1个[Na(H2O)5]+离子和1个结晶水分子组成.在[α-SiW11CuO39]6-单元中,缺位位点完全被一个铜原子占据,而不是被半个铜原子和半个钨原子所占据.值得注意的是,每个分子结构片段与4个邻近相同片段相连构筑有机-无机杂化三维框架.  相似文献   

10.
三唑类衍生物是重要的化工和药物合成中间体,而稠合三唑类衍生物因其独特的生理活性更是得到了广泛关注[1-2],其中3-三氟甲基-5,6,7,8-四氢[1,2,4]三唑并[4,3-α]哌嗪与β-氨基酸缩合得到的化合物是一类重要的二肽基肽酶-Ⅳ抑制剂 [3-4],可作为2型糖尿病的治疗药物,如2006年经美国FDA批准在美国上市的西他列汀(sitagliptin),此外二肽基肽酶-Ⅳ抑制剂还可用于肥胖症和高血压等疾病的预防和治疗[5].  相似文献   

11.
A new dysprosium-zinc coordination polymer {[Dy2Zn(dinic)4(H2O)8]·H2O}n 1(H2dinic = 2,5-pyridinedicaboxylic acid) has been synthesized and structurally characterized by X-ray analysis. The complex (C28H30Dy2N4O25Zn, Mr = 1212.94) crystallizes in triclinic, space group P-1 with a = 7.8911(16), b = 9.3177(19), c = 13.029(3)(A), α = 75.29(3), β = 75.04(3), γ =79.00(3)°, V = 887.1(3)(A)3, Z = 1, Dc=2.236 g/cm3,μ(MoKα) = 4.947 mm-1, F(000) = 570, the final R = 0.0345 and wR = 0.0903 for 3644 observed reflections with I> 2σ(I). A two-dimensional supramolecular structure is formed in 1, which was characterized by elemental analysis, IR, TG analysis, and single-crystal X-ray diffraction.  相似文献   

12.
1INTRODUCTION Studies on the syntheses,structures,and proper-ties of lanthanide-transition metal complexes are currently of great interest not only due to their beha-viors as good models to investigate the nature of magnetic exchange interactions between3d and4f metal ions in magnetic materials but also to the fascinating coordination properties of Ln(III)[1~6].Although some infinite lanthanide(III)-transition metal compounds have been obtained by the con-ventional self-assembly reacti…  相似文献   

13.
The title compounds 4a~c were synthesized and characterized by IR,NMR and MS.The crystal structure of C16H13ClN4O2·HBr·H2O(I),the quaternary ammonium salt of 4c,was determined by X-ray diffraction analysis.I crystallizes in triclinic,space group P1 with a = 8.3121(8),b = 9.3885(8),c = 13.2903(12),α = 106.788(2),β = 95.204(3),γ = 110.871(2)o,V = 905.81(14)3,Z = 2,C16H16BrClN4O3,Mr = 427.68,Dc = 1.568 g/cm3,F(000) = 432.00,μ = 2.446 mm-1,R = 0.0496 and wR = 0.127.X-ray analysis reveals that C(15) in the BrCH2COOH molecule binds to the N(1) of pyrimidine ring to form the quaternary ammonium salt.Two adjacent I molecules are connected by hydrogen bonds through carboxylate oxygen,water molecule and hydrobromic acid.  相似文献   

14.
4-Hydroxypyridine-2,6-dicarboxylic acid (chelidamic acid, cdaH2) reacts with Mn(OAc)2 x 4H2O to form a 1D staircase structure with dimeric Mn(II) units connected by water clusters to form a 3D framework, {[Mn2(cda)2 x 4H2O] x 4H2O}n, 1, in aqueous pyridine at room temperature. The compound crystallizes in the triclinic space group P1 with a = 9.495(3), b =10.733(5), c = 11.065(4) A, alpha = 87.42(5), beta = 74.14(5), gamma = 80.07(2) degrees, U = 1068.5(9) A3, Z = 2, rho(calcd) = 1.915 g cm(-3), T = 100 K, mu = 1.28 mm(-1), R1 = 0.0453 (I > 2sigma(I)), wR2 = 0.1046, GOOF = 1.282. Upon removal of the water molecules by heating, the 3D structure breaks down. Thermogravimetric analysis, infrared, X-ray powder diffraction studies, and X-ray crystallography were performed to characterize this compound. Since the coordination polymer has diaqua-bridged Mn(II) centers, it was subjected to variable-temperature magnetic studies.  相似文献   

15.
The hydrothermal reaction of copper chloride dihydrate and 5,5-dimethyl-imidazolidine,-2,4-dione with a mole ratio of 1:1 in acetonitrile resulted in the formation of a new acetate-bridged dinuclear copper complex, [C2H6ON]2[Cu2Cl2(μ-CH3COO)4]. Protonated acetamide in eaolie form and acetic acid were yielded by the hydrolysis of acetonitrile under hydrothennal condition. The rifle complex (C12H24Cl2Cu2N2O10) was characterized by X-ray single-crystal diffraction, IR spectrum, elemental and electrochemical analysis. It crystallizes in the monoclinic system, space group P21/c with a = 8.298004), b = 14.358(2), c = 12.0010(2) A^°, β= 130.620(3)°, V = 1085.3(2) A^°^3, Dc = 1.696 g/cm^3, 34, = 554.31, Z = 2, F(000) = 564 and μ = 2.254 mm^-1. The crystal structure consists of a tetraacetate-bridging dinulcear copper complex anion [Cu2Cl2(μ-CH3COO)4]^2-, with the chlorine anions in the axial positions, and two protonated acetamide cations [C2H6ON]^+, which were connected through hydrogen bonds to form a three-dimensional infinite network.  相似文献   

16.
孔春燕 《结构化学》2011,30(3):336-339
A novel manganese(Ⅱ) coordination polymer with 2-(4-carboxyphenoxy) benzoic acid (2,4'-H2oba) and 1,10-phenanthroline (1,10-phen) has been prepared by hydrothermal synthesis and characterized by single-crystal X-ray diffraction, IR and elemental analysis. Compound [Mn(2,4'-oba)(1,10-phen)] is of monoclinic system, space group P21/n with a = 7.960(1), b = 15.464(2), c = 18.703(3) , β = 99.976(2)°, V = 2267.5(6) 3, Z = 4, Mr = 491.35, Dc = 1.439 g/cm3, F(000) = 1004 and μ = 0.623 cm·1. The final R = 0.0419 and wR = 0.0978 for 3444 observed reflections with I > 2σ(I). X-ray diffraction analysis reveals that the oba2-ligands adopt a bis(chelating bidentate) mode to link two Mn(Ⅱ) centers to form an infinite 1D helical chain. Furthermore, a 3D supramolecular structure was formed by π-π stacking interactions and hydrogen bonds.  相似文献   

17.
A new complex [Zn(OH2)(HDPA)2]·3H2O 1 (H2DPA = 2,6-pyridine-dicarboxylic acid) has been prepared at room temperature from the reaction of zinc(II) chloride and 2,6-pyri- dine-dicarboxylic acid in mixed solvent of H2O and EtOH with pyridine, and characterized by X-ray analysis and thermal analysis, exhibiting that the coordination geometry of Zn(II) ion is an octa- hedron. Crystal data: ZnC14H16N2O12, Mr = 469.66, monoclinic, P21/n, a = 7.0067(3), b = 23.8215 (12), c = 10.7404(3)(A), β = 99.823(2)°,V = 1766.40(13)(A)3, Z = 4, Dc = 1.766 g/cm3, F(000) = 960, μ = 1.463 mm-1, R1 = 0.0462 and wR2 = 0.0884 (I > 2σ(I)).  相似文献   

18.
A novel cobalt(II) coordination polymer,[Co(BTEC)1/2]n 1,has been synthesized with Co(NO3)2·6H2O and 1,2,4,5-benzenetetracarboxylic acid (H4BTEC) by the hydrothermal method,and characterized by elemental analysis,IR and single-crystal X-ray diffraction. Crystallographic data for 1: C5HO4Co,Mr = 183.99,monoclinic,space group C2/c,a = 16.619(6),b = 7.416(3),c = 8.040(3)A,β = 90.612(4)°,V = 990.8(6) A^3,Z = 8,Dc = 2.467 g/cm^3,μ = 3.390 mm^-1,F(000) = 720,R = 0.0307 and wR = 0.0847 for 912 observed reflections (I 〉 2σ(I)). X-ray crystal structural analysis revealed that each Co(II) adopts a tetrahedral coordination mode to link four separate BTEC ligands via uniform monodentate carboxylate groups and each BTEC ligand possesses an 8-connected geometry to connect eight Co(II) ions. Complex 1 exhibits a rare (4,8)-connected net with (45.6)2(410.614.84) topology.  相似文献   

19.
朱志博  路新卫 《结构化学》2010,29(3):465-470
A new 1D coordination polymer,{[Mn2(4',4-hbc)4(4',4-Hhbc)2(H2O)]·H2O}n(4',4-Hhbc=4'-hydroxyl-biphenyl-4-carboxylic acid),has been hydrothermally synthesized and struc-turally characterized by elemental analysis,IR spectroscopy and single-crystal X-ray diffraction.The crystal belongs to the monoclinic system,space group C2/c with a=52.421(10),b=7.5388(15),c=16.478(3),β=106.12(3)°,V=6256(2)3,Z=4,C78H62Mn2O21,Mr=1445.16,Dc=1.534g/cm3,μ(MoKα)=0.490mm-1,F(000)=2992,R=0.0764 and wR=0.2006 for 2984 observed reflections with I2σ(I).X-ray diffraction analyses reveal that the title compound is a one-dimensional infinite chain,in which the MnⅡ atom adopts a distorted octahedral geometry coordinated by four 4',4-hbc ligands,one 4',4-Hhbc ligand and one water molecule.Furthermore,the luminescent property of title compound was investigated.  相似文献   

20.
The title compound glycin·3,5-dihydroxybenzoic acid (GDB) has been synthesized and characterized by single-crystal X-ray analysis. It crystallizes in orthorhombic, space group Pca21 with a = 25.513(10), b = 4.668(2), c = 9.150(4)(A), Z = 4, V = 1089.8(8)(A)3, C9H13NO7, Mr = 247.20, Dc = 1.507 g/m3, μ(MoKα) = 0.132 mm-1, F(000) = 520, R1 = 0.0322 and wR2 = 0.0611 for 885 observed reflections (I > 2σ(I)). The title compound is a 1:1 molecular complex of glycin and 3,5-dihydroxybenzoic acid, which is linked by O-H…O and N-H…O hydrogen bonds to form a three-dimensional framework. Test of SHG (second harmonic generation) indicates that NLO generation of the crystal is higher than that of KDP.  相似文献   

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