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1.
2.
Crystal structures of 5-(5-methylthien-2-yl)-2-deoxyuridine (I), 5-(5-thien-2-yl)-2-deoxyuridine (II) and 5-(5-bromothien-2-yl)-2-deoxyuridine (III) have been obtained from data collected on a four-circle Enraf-Nonius diffractometer (CAD-4 system). Space group, unit/cell parameters and finalR indices are:I, monoclinic,P21,a=9.105(2),b=20.819(2),c=7.932(2) Å, =98.79(2)°,R=5.7%;II, monoclinic,P21,a=8.720(4),b=20.793(4),c=7.884(4) Å, =95.06(2)°,R=5.8%;III, monoclinic,P21,a=9.260(2),b=41.655(7),c=7.926(2) Å, =97.996(13)°,R=9.4%. Structural properties of the title compounds are compared with those of 5-(5-chlorothien-2-yl)-2-deoxyuridine (IV) previously reported in order to explain their affinity for HSV-1 thymidine kinase and their eventual interaction with viral DNA polymerase. The main structural features observed are the coplanarity of the uracil and thienyl cycles stabilized by a S–O intramolecular interaction and the formation of dimeric intermolecular H bonds between two uracil moieties.  相似文献   

3.
The crystal and molecular structure of cyclopentadienyl-carbonyl-triphenylphosphine-phenylacetyl-iron (1) has been determined on the basis of X-ray data. The crystals are triclinic, space groupP¯1 (Z=2) with cell dimensions:a=9.546(1),b=10.233(1),c=5.012(2) Å,=93.70(1),=101.12(1), =112.58(1)°. The structure was solved by direct methods and refined anisotropically by a full-matrix, least-squares procedure against 4964 independent reflections, givingR=0.0416. The MM calculations done for a model of1 reproduced satisfactorily the X-ray structure.On leave from the Shanghai Institute of Organic Chemistry, Chinese Academy of Sciences, Shanghai, China.  相似文献   

4.
The crystal structure of [(HOCH2CH2)3NH][Zn(H2O)2(H2.5 L)2] ? 5H2O, where H4 L is 1-hydroxyethane-1,1-diphosphonic acid, was determined by X-ray diffraction. The anionic complex has a cis-octahedral structure. The zinc atom is coordinated by four O atoms of two bidentate chelate H2.5 L 1.5? ligands and two O atoms of water molecules. The Zn-O(L) bond lengths range between 2.050 and 2.175 Å, and the Zn-O(H2O) bond lengths are 2.105 and 2.133 Å. The anionic complexes, triethanolammonium cations, and molecules of crystallization water are interlinked by an extensive network of hydrogen bonds. The crystallographic data for isostructural complexes of cobalt and nickel are given.  相似文献   

5.
在单晶X射线衍射实验的基础上,对孔道结构化合物V9P8-en的类质同象物V9(P,B)8-en的晶体结构和晶体化学进行了深入研究.结果表明,该化合物的晶体学数据为:P2(1)/n,a=1.43134(9)nm,b=1.01256(6)nm,c=1.83156(12)nm,β=90.280(2)°,V=2.6545(3)nm3,Z=2,R=0.0540,wR2=0.1551.结构中,沿着三个结晶轴方向发育复杂而规整的三维孔道,最大孔径达1.83nm(∥b轴),质子化乙二胺和水分子居于孔道中.硼部分替代四面体配位的磷,替代率为B8:P8=0.1838:7.8162;其中B与{P-OH}位P的替代量大于与[P-O]位P的替代量.相对于V9P8-en来说,V9(P,B)8-en的晶胞参数发生了变化,导致b轴增长(1.0150→1.0256nm)和c轴缩短(1.8374→1.8316nm),同时β角变小(90.39→90.278(2)°).二者的化学计量比也不同,体现在结构与孔容的关系、电荷平衡、满足亲水-疏水作用的结晶水的数量及有机模板分子的赋存状态等方面都有差异.  相似文献   

6.
Treatment of (μ-SCH2CH2CH2S-μ)Fe2(CO)6 with equimolar 2-C5H4NPPh2 in the presence of Me3NO·2H2O in CH2Cl2/MeCN solutions gave the title complex (μ-SCH2CH2CH2S-μ)Fe2(CO)5(2-C5H4NPPh2) in 76% yield. The title complex was characterized by spectroscopy as well as by single crystal X-ray diffraction analysis. The molecular structure consists of a butterfly [Fe2S2] cluster with propane, five carbonyls, and 2-C5H4NPPh2. In the crystal packing diagram, intermolecular C–H···O hydrogen bonds between phenyl and carbonyl groups stabilize the solid state.  相似文献   

7.
The crystal structure of the bis-amido complex of Ti(IV) (η5-C5H5)2Ti(NH(2,4-(C CSiMe3)2C6H3))2 is reported. This complex was prepared in 52% yield from the reaction of (η5-C5H5)2TiCl2 with two equivalents of LiNH(2,4-(C CSiMe3)2C6H3) (prepared in situ in THF at −78C). The substituted aniline H2N(2,4-(C CSiMe3)2C6H3) was prepared in 70% yield from the reaction of 2,4-dibromoaniline with Me3SiC CH using conventional Pd/Cu coupling methodology. The molecular structure of (η5-C5H5)2Ti(NH(2,4-(C CSiMe3)2C6H3))2 (monoclinic, space group C2/c, Z = 4, a = 29.7523(5) Å, b = 9.5339(2) Å, c = 15.8864(3) Å, β = 93.022(1) features a titanium (IV) center with a distorted tetrahedral geometry which lies on a crystallographic twofold axis. The amido units are arranged so that steric interactions are minimized. The Ti– N distance is 2.016(2) Å.  相似文献   

8.
Crystallography Reports - The structure and thermal properties of azobenzene derivatives R1–C6H4–N=N–C6H4–R2, where R1/R2 = CH3COO/C2H5O (I), CH2=C(CH3)COO/C2H5 (II), or...  相似文献   

9.
为了探讨化学成份对VPO体系孔道结构化合物结构稳定性的影响,根据酸碱平衡原理进行了合成实验设计;利用V2O5、H3PO4、H3BO3等简单的无机前驱物、乙二胺作结构导向剂,水热法合成了孔道结构钒硼磷酸盐化合物(H3NCH2CH2NH3)2(H3NCH2CH2NH2)[VⅢ(H2O)2(VⅣO)8(OH)4(H(P,B)O4)4((P,B)O4)4(H2O)2]·3H2O(简称V9(P,B)8-en).典型的反应起始物摩尔比为n(V2O5):n(H3BO3):n(H3PO4):n(en):n(H2O)=0.89:3.50:3.50:3.60:265(pH值为6.5),在175℃、自生压力条件下恒温晶化6.5d(最终pH值为5.9).通过电子探针、粉末X射线衍射、红外吸收光谱、原子占位度修正等方法,对产物的化学成份、物相及其结构等进行了实验研究.证实V9(P,B)8-en为V9P8-en的类质同象化合物,不同晶粒中B与P的含量有差别,B与P之比为O.1:7.9~2.54:5.46(原子比),但恒有V:(P+B)≈9:8.表明通过合理设计和控制合成条件,可在保持V9P8-en基本结构不变的前提下通过同晶取代引入新的化学成份,并由此探讨成份与结构稳定性的关系.  相似文献   

10.
以乙醇为溶剂,在低温条件下合成出了两种手性硼磷酸盐化合物BaBPO5(1)(T=120℃,t=5d)和(H3O)Zn(H2O)2BP2O8·H2O (2)(T=80℃,t=5d).XRD单晶衍射仪测定了化合物的结构,结果表明:(1)属三方晶系,P3221空间群,a=b=7.1162(3)(A),c=6.9979(6),(A)=3,该晶体含有一维线性链状阴离子结构;(2)属六方晶系,P6122空间群,a=b =9.513(2)(A),c=15.906(8),(A)=6.该晶体具有三维骨架结构.实验结果表明使用乙醇作溶剂可以极大降低硼磷酸盐的合成温度,进而有助于获得手性硼磷酸盐化合物,这为手性硼磷酸盐的合成提供了一种新思路.  相似文献   

11.
Protonation of Fe( 5-C5H5)[( 5-C5H4)(2-C5H4N)]1 in 98% H2SO4 followed by dilution with water and addition of NaBF4 yields Fe( 5-C5H5)[( 5-C5H4)(2-C5H4NH+)](BF 4 )2 instead of a ferrocinium derivative. Complex2 crystallizes in the monoclinic system, P21 /a:a=7.984(1),b=9.981(2),c=18.220(4) Å,=102.31 (1)°,V=1418.5 Å3,Z=4. The pyridinium ring makes a dihedral angle of 21.0(2)° with the cyclopentadienyl ring to which it is bound. One F atom of BF 4 is involved in short van der Walls contacts with the N (2.764(5) Å) and the H (2.08(6) Å) atoms of the NH+ moiety.  相似文献   

12.
The structure of the Cu(II) complex of gly-l-tyr [Cu(C11N2O4H13) (H2O)2]·2H2O has been solved by X-ray diffraction methods. The compound crystallizes in the orthorhombic space groupP212121 witha=11.970(2) Å,b=12.485(2) Å andc=10.418(3) Å, respectively, (MoK)=0.710 Å,D c =1.59 Mgm–3,D m =1.59 Mgm–3, finalR=0.04. The structure was solved by heavy atom (Cu) phased Fourier and refined by full-matrix least squares methods. The coordination geometry of the ligand around the Cu(II) ion has been established as a distorted tetragonal pyramid. The peptide molecule behaves as a tridentate ligand via its amino (N2), amido (N1) nitrogens and carboxyl (O2) oxygens. The peptide nitrogen is found to be deprotonated.  相似文献   

13.
Three new cyclohexaphosphates with general formula M0.5((C6H5CH2)2NH2)5P6O18·H2O (M=Co, Cu, Cd) are reported. They crystallize with monoclinic unit-cells and are isotropic. We have determined their structure from the salt M=Co. This later exhibits the following unit-cell parameters: a = 22.739(5), b = 17.682(3), c = 18.342(3) Å, = 91.22(1)°, Z = 4,P21/n, V = 7373 Å3, and Dx = 1.373 g cm–3. The atomic arrangement can be described as layers containing P6O18 ring anions and CoO6 octahedra spreading in the (101) planes and intercalated by the dibenzylammonium groups and the water molecules. Synthesis and characterization by X-ray diffraction, IR absorption, and TA are described.  相似文献   

14.
The crystal structure of 1,4-dihydro-6-methyl-5-N,N-diethylcarbamoyl-4-phenyl-2(3H)-pyrimidinethione, C16 H 21 N 3OS (1), is monoclinic, space group P21/n, a = 6.818(1), b = 13.211(2), c = 18.807(3) Å, = 99.53(1)°, V = 1670.6(4) Å3, Z = 4 and d cal = 1.206 Mg/m3, R = 0.042 (wR = 0.119) for 190 parameters and 2560 observations with I 2(I) and 1,4-dihydro-6-methyl-5-N-methyl carbamoyl-4-(2-nitrophenyl)-2(3H)-pyrimidinethione hemihydrate, C13 H 14N4O3S 0.5H2O, (2), is triclinic, space group P1, a = 7.513(1), b = 14.381(2), c = 15.506(2)Å, = 114.95(2), = 98.11(1), = 93.55(1)°, V = 1490.0(3) Å3, Z = 4 and d cal = 1.406 Mg/m3, R = 0.062 (wR = 0.165) for 388 parameters and 3094 observations with I 2(I).The compound 2 crystallized having two molecules in the asymmetric unit, which can be regarded as monohydrated dimers, and forming a hydrate. The conformation of the central heterocyclic ring (1,4-dihydropyrimidine) in both compounds was found to be close to a half-chair conformation. The 2-nitrophenyl substituent in 2 is in the axial synperiplanar orientation. In both compounds, the conformation of the 3-substituted carbamoyl group appears to be influenced by hydrogen bonding with anticlinal orientation observed for carbonyl groups serving as hydrogen bonding acceptors.  相似文献   

15.
The title compound has been synthesized, and characterized by means of X-ray, magnetic, and IR-spectroscopic measurements.The crystals of Cu(DPhP)2(H2O)2(DPhP=diphenylphosphate) are monoclinic, space groupI2/c witha=24.126(6),b=8.510(2),c=12.333(3) Å,=90.73(5)° andZ=4. The structure was solved by the heavy-atom technique, and refined by full-matrix least-squares calculations to a finalR of 0.040 for 1494 reflections.The complex is centrosymmetric, and the Cu atom at a center of symmetry is four-fold coordinated with two oxygen atoms from two phosphate groups and two water molecules. The coordination about the Cu atom is square-planar, with Cu-O and Cu-O(W) distances 1.926(3) and 1.912(3) Å, respectively.The O(2) phosphate oxygen is an acceptor of two H bonds; one of them is an intramolecular O(W)-H(2)O(2) of 2.714(4) Å, and the other is an intermolecularO(W)-H(1)O(2i) of 2.667(4) Å. Their presence is also deduced from the IR spectrum of this compound at 3250 and 3000 cm–1, respectively.The calculated magnetic moment value of 1.92 B.M. corresponds to that of the monomeric copper(II) complexes including those of some alkyl phosphates.  相似文献   

16.
本文采用水溶液中生长晶体的方法合成了KLnN的单晶,研究了KPrN的单晶结构及KLnN的非线性光学性质。KLnN均属正交晶系,Fdd2空间群。KPrN的晶胞参数为:a=2.1411(3)nm,b=1.2210(10)nm,c=1.2208(2)nm,Z=6,R=0.0240,KLnN(Ln=Pr,Nd)的二次谐波光强与KLnN处于同样的数量级。  相似文献   

17.
The crystal structure of octacalcium bis(hydrogenphosphate) tetrakis(phosphate)pentahydrate, Ca8(HPO4)2(PO4)4·5H2O, has been refined toR=0.051 for 4502 reflections. The crystals are triclinic:P¯1,a=19.692(4),b=9.523(2),c=6.835(2) Å,=90.15(2),=92.54(2), and =108.65(1)°,Z=2. The structure can be considered to consist of two layers parallel to (100), an apatitic layer which corresponds very closely to that of hydroxyapatite and a hydrated layer which contains all the water molecules. Several atoms in the hydrated layer are probably disordered. Possibilities for the hydrogen-bonding arrangement are discussed.  相似文献   

18.
The complex [Ni(H2O)3(phen)(C4H2O4)] H2O (1), which was obtained by reaction of phenanthroline, Ni(NO3)2 6H2O, and maleic acid in CH3OH/H2O at pH = 7.05, crystallized in the monoclinic space group P21 (no. 4) with cell dimensions: a = 9.350(1) Å, b = 7.631(1) Å, c = 12.821(1) Å, = 106.25(1), and D calc = 1.607 g/cm3 for Z = 2. The Ni atoms are each octahe drally coordinated by one chelating phen ligand, three H2O molecules and one monodentate maleato ligand to form [Ni(H2O)3(phen)(C4H2O4)] complex molecules with d(Ni–O) = 2.038–2.090 Å, d(Ni–N) = 2.066, 2.089 Å. The formed complex molecules are, via the intermolecular hydrogen bonds, assembled into columnar 1D chains. Interdigitation of the chelating phen ligands of the neighboring chains leads to 2D layers and the crystal H2O molecules are hydrogen bonded to the oxygen atoms of the maleate not coordinated to the Ni atom. However, reaction of NiCO3, phen, and maleic acid in CH3OH/H2O at pH = 6.33 afforded [Ni(H2O)2(phen)(C4H2O4)] 2H2O (2), which crystallized in the triclinic space group (no. 2) with cell dimensions: a = 7.971(1) Å, b = 8.237(1) Å, c = 13.304(1) Å, = 81.005(6)°, = 87.877(8)°, = 78.322(8)°, and D calc = 1.671 g/cm3 for Z = 2. The Ni atoms are each octahedrally coordinated by two N atoms of one phen ligand and four O atoms of two H2O molecules and two bis–monodentate maleato ligands with d(Ni–O) = 2.041–2.120 Å and d(Ni–N) = 2.095 Å. The Ni atoms are bridged by the maleato ligands to generate 1D 1 [Ni(H2O)2(phen)(C4H2O4)2/2] chains along [100]. The supramolecular assemblies of the 1D chains via – stacking inter- actions result in thick 2D layers parallel to (001), between which the noncoordinating H2O molecules are sandwiched. The paramagnetic [Ni(H2O)2(phen)(C4H2O4)2/2] 2H2O (2) obeys the Curie–Weiss law m(T-) = 1.139cm3 mol–1 K with the Weiss constant = –0.95 K.  相似文献   

19.
Crystallography Reports - The conditions for synthesis of [Ni(H2NCH2CH2NH2)3]Cl2 ⋅ 2H2O ([Ni(en)3]Cl2 ⋅ 2H2O) crystals from aqueous solutions have been considered. The synthesized...  相似文献   

20.
Synthesis and X-ray diffraction study of {NH2C(NHC6H5)2}3[UO2(C2O4)2(NCS)] · 1.25H2O single crystals have been performed. This compound is crystallized in the orthorhombic system, with the unit-cell parameters a = 45.2646(8) Å, b = 57.7359(11) Å, c = 7.9244(3) Å, sp. gr. Fdd2, Z = 16, V = 20 709.6(10) Å3, and R = 0.0477. The uranium-containing structural units of the crystals are one-core groups of the [UO2(C2O4)2(NCS)]3? composition, belonging to the crystallochemical group AB 2 01 M 1 (A = UO 2 +2 , B 01 = C2O 4 2? , M 1 = NCS?) of uranyl complexes. The uranium-containing complexes are connected into a three-dimensional framework owing to the electrostatic interactions with the outer-sphere cations and a system of hydrogen bonds.  相似文献   

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