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《结构化学》1990,(3)
<正> 2 - acetyldiferrocenylmethane, C5H5FeC5H4CH2C5H3 (COCH3) FeC5H5 ( I ),Mr=426. 1,violet-red prism-like crystal,m. p. 163. 7~166. 3℃,obtained from benzene-ligroin solution (benzene : ligroin=1 : 3). A crystal of approximate dimensions 0. 20×0. 40×0. 45 mm was selected for data collection from a CAD4 diffractometer with graphite monochromated MoKa radiation (λ=0. 71069A). Compound Ⅰ crystallized in the triclinic space group P1 with unit cell dimensions;a = 9. 597(2),b=9. 768 (2),c=11.540(1) A ,α= 111-93(1),β=111. 42(1),γ= 92. 46(2)°,V = 913. 9 A3, Z= 2, and Dc= 1. 548 g/cm3. 3' - Acetyldiferrocenylmethane, C5H5FeC5H4CH2C5H4FeC5 H4-COCH3(Ⅱ) ,is an isomer of compound Ⅰ ,yellow needle-like crystal,m. p. 110. 5~ 111. 0℃ ,obtained by the same method. A crystal of approximate dimensions 0. 025×0. 01×0. 45 mm was selected for data collection. Compound Ⅱ crystallized in monoclinic space group P21/c with a = 10. 930 (2), b= 5. 907(6) ,c= 27. 729(5) A ,β= 92. 64 (1)°,V=1788. 4A3,Z=4,Dc=1. 583 g/cm3. 相似文献
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《结构化学》1986,(1)
<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
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《结构化学》1988,(1)
<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
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《结构化学》1986,(3)
<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
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<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
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《结构化学》1986,(1)
<正> INTRODUCTION. 7-hydroxy-8-methoxy-4(1H) quinolone(Q), C_(10)H_9NO_3, is a new compound isolated from the Chinese soft coral, Sinularia Polydacryla. This compound has a marked effect on increasing the circulation of blood in a white mouse brain system or heart system and on alleviating the hypoxia suffeting. It could mitigate the arrhythmia caused by aconitine. Up to now, only a few structures of quinoline derivatives have been determinated by X-ray diffraction. 相似文献
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《结构化学》1992,(4)
<正> 3-Benzoylcoumarine C16H10O3, Mr = 250. 26, monpclinic, space group P21/n, a =11. 744(1), 6 = 16.837(2), c=12. 525(2)A , β= 100. 00(1)°, Z = 8, Dc =1. 363g/cm3, Do = 1. 382g/cm3, F( 000) = 1040, μ(MoKa) = 0. 880cm-1. R and Rw were 0. 048 and 0. 049, respectively, for 2490 observed reflections. X-ray structural analysis reveals that the title compound contains 3 planes intersecting each other with different dihedral angles and thus the whole molecule displays non-planar configuration. This result is consistant with the previous conclusion from photochemical study. 相似文献
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《结构化学》1985,(1)
<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
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《结构化学》1992,(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
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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
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《结构化学》1989,(1)
<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