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1.
<正> Triptonide, C20H22O6, was extracted from tripterygium wilfordii Hook F. of Fujian province and its structure was determined by X-ray crystallo-graphic analysis, Mr = 358. 39, monoclinic, P21,a = 11. 144(5), 6 = 6. 467(2), c= 12. 681(6)(?), β=103.54(4)°, V= 888. 4(?)3. Z = 2, F(000) = 380, Dc= 1. 34g/ cm3. The structure was solved by direct methods and refined by full matrix least-squares method to a final R value of 0. 042 for 1934 reflections with I> 3σ(I). Crystals of triptonide are isostructural with those of triptolide.  相似文献   

2.
The crystal structure of [Ni(TAAB)(py)_2](BF_4)_2,where TAAB is thetetradentate macrocyclic ligand tetrabenzo[b,f,j,n] [1,5,9,13]tetraazacyclohexadecine,has been determined from X-ray diffraction analysis.The crys.tai beiongs to monoclinic,space group P2_1/n with cell parameters  相似文献   

3.
<正> The title complex crystallizes in the triclinic system, space group P1, a =11. 912(4), b = 13. 626(2), c=10. 040(3)(?), a=95. 03(2) ,β= 114. 8 (3), γ = 73. 58(3)°, V = 1418.0(?)3, Z = 1, D,= 1. 37g/cm3, F(000) = 612, R = 0. 064 for 4860 independent reflections [I>3σ(I)]. Each Cu atom is coordinated by the oxygen atoms from the C10H7CH2COO groups and DMF in a square pyramid geometry.  相似文献   

4.
<正> C14H10N2,Mr =206.24, space group P21/n, a =5.861(3), b =10.230 (5), c =17.440(11) A,β=92.07(5)°,V= 1045(1) A3,Z=4, Dx=1.31 g.cm-3, MoKa radiation,u=0.73 cm-1,F(000)=432,R=0.063 for 1054 observed reflections. 2-Phenylquinoxaline molecule is approximately planar. The dihedral angle between the quinoxaline ring and the substituted phenyl ring is 7.0°. The C-C bond distance connecting these two rings is 1.495(4) A. The whole molecule is a conjugation system.  相似文献   

5.
<正> The title compound, C24H20As2(Mr=458.24), crystallizes in mono-clinic with space group P21/n and a=6.268(2), b=7.494(2), c=21.340(7)A, β= 91.027(3)°, V=1002.6 A3, Z=2, D.x=1.518gcm-3. The final value of R is 0.059 for 1619 observed reflections. The four phenyls arrange in a staggered trans-conformation around the As-As' bond.  相似文献   

6.
<正> INTRODUCTION. Four compounds of diterpenoids that have in vitro cytotoxity against cultured Hala cells have been obtained by means of extraction from Rabdosia serra(Maxim) Hara, a chinese medical herb. They are Rabdoserrin A (Rab A), Rabdoserrin B (Rab B), Excisanin A and Kamebakaurin (Kam). Among them, Rab A and Rab B are new compounds. Crystal structures of Rab A and Kam have been solved. The chemical structure of Rab B has been  相似文献   

7.
8.
<正> C18H25NO5, Mr = 335.40, tetragonal, P41212, a = 15.578(4), c =14.723(3) A, V =3573(2) A3, Z = 8, D = 1.247 g cm-3, MoKα,λ= 0.71069 A, μ = 0.;85 cm-1, T = 293K, final R .= 0.100 and RW (on F2) = 0.080 for 1095 observed data [|FO| > 2σ(|FO|)]. The structure confirms the spectrbscopic assignment of a pentacyclic skeleton containing two α-methyl-γ-lactone rings, one ether and one tertiary amine.  相似文献   

9.
<正> Introduction. Rabdoserrin-D C_(20)H_(30)O_5 is extracted from Rabdosia serra (Maxim) Hara, a Chinese medical herb with antitumourous activities. Tests show that this compound has a high inhibitory effect on the Hela cell cultured outside the body and thus it is worth further studying, The investigation on the  相似文献   

10.
11.
<正> To elucidate structural relations between benzo-13-crown-4 and its similar crown compound. We determined the crystal structure of the title compound, which is a pure crown. The results of our investigation show that the dihedral angle between the planes of benzo-ring and of the O-atoms in the crown ring is 43.5°. The related distances between O atoms in benzo-13-crown-4 are 2.651 to 4.906, respectively.  相似文献   

12.
<正> Au [SC(NH2)2]2C1O4, Mr,= 448. 66, orthorhombic, Pcca, α= 17. 873 (2),b = 8. 2933(7), c = 7. 196(2) A V=1066. 6A3,Z=4,DC = 2. 794g·cm-3,R= 0. 049,Rw=0. 068 for 807 observed reflections. The structure consists of complex cation Au[SC(NH2)2]2+ and perchlorate ion ClO4-. The gold atom( I ) in the cation has a slightly bent linear coordination geometry.  相似文献   

13.
<正> Cluster compound [Mo4(μ3-O)2O4Cl2(o-CH3C6H4COO)6] has been prepared by the reaction of molybdenum pentachloride and o-methylbenzoic acid. It crystllizes in the orthorhombic space group Praia with cell parameters:Mr= 1361. 6,a=13. 792(4), b=17. 957(3),c= 20. 974(9) A ,V=5194(2) A3,Z= 4,Dc= 1. 74g/cm3,F(000) = 2704,μ(MoKa) = 11. 0/cm. The final R=0. 061 and Rw=0. 064 for 1441(I>3oooooooooo(I)) observed unique reflections. The tetranuclear complex molecule, where the molybdenum atoms are bridged by two μ3-O atoms and six bidentate o-methylbenzoato ligands,is located at crystallographic two-fold axis(x,-1/4,1/4) with one Mo-Mo bond of 2. 610A  相似文献   

14.
<正> The crystal structure of (Cyanoethyloxy-ferrocenyl)-p-fluoro-phenyl methane (Fc-C(H)OCH2CH2CN, Mr=363.23) belongs to the monoclinic spacegroup P21/c with unit cell parameters: a =9.751(3), b =18.448(4), c =9.891(4)A,β= 105.71(3)°,V= 1712.7A3,Z=4,Dc=1.409g/cm3,μ=8.930cm-1,λ=0.71073A (MoKα),R=0.05. The structure and reactivities of the title compound are compared with those of its isomer.  相似文献   

15.
The crystals of alkaloid Dehydrocrydaline chloride (C_(22)H_(24)NO_4·HCl) belong to the orthorhombic system. The space group is D_(2k)~(14)-Pbcn with the unit cell parameters of a=8.528,b=23.317 and c=24.798, and eight molecules per unit cell. The coordinates for all the non-hydrogen atoms were found by using direct methods and Fourier syntheses. During the course of refinement of this structure (using least squares and difference Fouriers), it was discovered that there are 4.5 water molecules with different occupancies in one asymmetric volume of the unit cell. The anisotropic refinement of non-hydrogen atoms and the isotropic refinement of non-aqueous hydrogen atoms led to a final R-factor of 0.053. Water molecules formed a relatively complex network around chloride ion.In this paper the small molecule structure and the network of water molecules are described.  相似文献   

16.
<正> The structure of humosine A, C20H19NO5, which represents a new kind of phthalide isoquinoline alkaloid,has been determined by X-ray diffraction analysis. The compound crystallized in the space group P212121 with a=7.654(2), b=12.926(2), c= 17.018(8) A, Z=4, V=1681.7A3, Dx=1.459g.cm-3, μ(Moke(?))=1.014 cm-1, F(000)=776. The structure was solved by direct methods, and refined by full-matrix least-squares with final R = 0.032 for 1517 observed reflections (I≥3σ).  相似文献   

17.
<正> INTRODUCTION. By mixing aqueous solutions of AgNO_3-Tu(mol ratio 1:1, Tu==SC(NH_2)2) with CuCI-Tu(mol ratio 1:3) we obtained a colourless crystalcompound. Its crystal and molecular structure was determined by X-raydiffraction and shortly reported in this paper.  相似文献   

18.
<正> The crystal and molecular structure of the title compound was determined by single crystal X-ray diffraction method. The complex crystallizes in the mono-clinic space group P21/n with a = 10. 306 ( 3) , b = 10. 161 (2), c = 14. 798 ( 4) A . β= 108. 52(2)°, V= 1469. 4(6)A3,Z= 4. The structure was solved by direct methods. Least-squares refinement converged to a final value of R = 0. 043 and Rw= 0. 040 for 1237 reflections. The molybdenum (Ⅵ) ion is bonded to two chlorine atoms, two oxo atoms and two oxygen atoms from two monodentately and weakly coordinated carboxyl groups of molecules C4H3OCOOH, forming a octahedron. The Mo-O distances are in the range 1. 66 - 2. 39A ,the Mo-Cl distances fall in the range 2. 33-2. 34A.  相似文献   

19.
<正> MoO2(C9H5NOH)2, Mr = 396,monoclinic,space group Cc,a = 13.369 (6), b = 9.408(4), c = 13.560(3)A,°=109.65°,V=1605A3,Z= 4,Dc= 1.639 g/cm3.R=0.027 for 1372 observed reflections [I>3o(I)]. X-ray analysis showed that the coordination sphere around molybdenum atom has a distorted octahedral geometry with two terminal oxygen atoms arranged in cis-form and two oxines act as bidentate ligands connected to the molybdenum through O and N atoms.Therefore, the molecule is not as Atovmyan described that the molybdenum atom is located on two-fold axis with space group C2/c but only approxiaately C2 synmetry.  相似文献   

20.
The title compound has been prepared by reaction of VOSO_4 with hydroxyacetic acid in aqueous solution, adding KOH to a suitable pH value. The crystals are monoclinic, space group P2_1/b with cell parameters: α=10.075(2), b=9.857(3), c=14.314(3), γ=115.29(2)°, Z=4. Intensities of 1714 independent reflexions having I≥3σ(I) were collected on a CAD4 diffractometer with MoKα radiation. The structure was solved by Patterson and direct methods and refined by full matrix least-squares method to R=0.060. In the complex the ratio of centric V atom to hydroxyacetate ligands is M:L=1:3, two hydroxyacetate ligands are chelated to V atom in a cis arrangement, the other is monodentate ligand with a carboxyl O atom to grasp the cation VO~(2+).  相似文献   

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