二甲基-2'-乙酰基双二茂铁甲烷的晶体和分子结构

二甲基-2′-乙酰基双二茂铁甲烷C_5H_5FeC_5H_4C(CH_3)_2C_5H_4FeC_5H_4COCH_3为深紫色菱形晶体,m.p.115.5～116.5℃。它属单斜晶系,P2_1/c空间群。晶胞参数为:a=11.626(1),b=13.219(1),c=13.078(2)A,β=90.67(1),V=2009.8A~3,Z=4,Dc=1.501g/cm~3。用MULTAN-78直接法程序求解晶体结构,最后偏离因子R=0.040。中心C原子周围的四个基团以变形四面体取向,分子本身不具有任何对称性。     

2-乙酰基雌酚酮和2-乙酰基雌二醇-17β-乙酸酯的晶体和分子结构

雌甾化合物的晶体结构已有较多的研究,本文用X射线衍射法对2-乙酰基雌酚酮(Ⅰ)和2-乙酰基雌二醇-17β-乙酸酯(Ⅱ)二化合物的晶体和分子结构进行了研究。 1 实验 1.1 晶体培养 样品(Ⅰ)和(Ⅱ)按文献所述方法合成。在室温下将(Ⅰ)的吡啶溶液置于充满甲醇蒸气的密闭容器中,使溶液保持过饱和状态而逐渐长成浅黄色的透明晶体。将(Ⅱ)溶于乙酸乙酯中,经重结晶得无色的透明晶体。     

N-二茂铁甲酰基-N'-对乙酰基苯基硫脲的晶体及分子结构

合成的标题化合物晶体属单斜晶系, 空间群为P2~1/α, 晶胞参数为:α=0.9771(2), b=1.6752(6), c=1.1552(3)nm; β=109.23(2)°, 体积V=1.785(2)nm^3, Z=4, D~x=1.42g/cm^3, 最终偏差因子R=0.047, R~ω=0.051。结构分析表明, 在N'H-C(S)-NH-C(O)中的羰基氧和N'上的氢之间生成分子内氢键, 其为包括氢原子在内的平面六元环, 并且在二茂铁中的两个茂环平行。结合^1HNMR, IR谱矛以确证, 指出N原子上的氢应在高场(～8.0)N'上的氢原子化学位移应在低场(～12,0)。     

β-氰乙基-α-二茂铁邻氟代苄基醚的晶体和分子结构

二茂铁衍生物的氰乙基化反应,对于探求新的二茂铁衍生物合成途径及用途具有一定意义。本文用X射线衍射方法测定了标题化合物的分子和晶体结构,为探索氰乙基化反应提供必要的结构佐证。     

N-苄基-N-(2-氰乙基)-二茂铁磺酰胺的晶体和分子结构

N-等基-N-(2-氰乙基)-二茂铁磺酰胺[C₅H₅FeC₅H₄SO₂N(C₂H₄CN)CH₂C₆H₅]为黄色柱状晶体,属单斜晶系,空间群P2₁/n,晶胞参数为:α=8.750(1),b=12.876(5),c=16.744(2)Å,β=94.75(1)°,V=1880.0ų,Z=4,计算密度D_calc=1.442g/cm³。在CAD-4四园衍射仪上,用MoK_α射线收集衍射数据,用Patterson函数法和差值Fourior合成求解晶体结构。经以2226个独立衍射点用全矩阵最小二乘修正,最后使偏离因子R=0.0466.分子中S原子、N原子以不等性sp³杂化与周围原子健合。     

β-氰乙基-α-二茂铁邻氟代苄基醚的晶体和分子结构

This paper reports the crystal and molecular structure of β-cyanoethyl-α-ferro cenylfluorobenzyl ether (C_5H_5FeC_5H_4CH(OCH_2CH_2CN)C_6H_4F). The title crystal belongs to the triclinic system and the space group is P1 with crystal parameters: a=0.7849(8) nm, b=1.1744(3) nm, c=1.9337(4) nm, α=74.99(1)°, β=87.28(5)°, γ=86.61(5)°, V=1.7176(2) nm, Z=4, D_c=1.405 g cm~(-3). The crystal was solved with direct method and fourier synthesis, refined with full matrix least-squares. The refinement eonveraged to R=0.043.There are two molecules in an asymmetry unit. The geometrical features of the molecules and the characteristics of the molecular packing are discussed.     

溪黄草甲素的晶体和分子结构

溪黄草甲素,C_(20)H_(26)O_5,M_r=346.43,是从中草药溪黄草(Radosia serra [Maxim] Hara)中提取得到的一种具有抗癌活性的化合物,它的结构式已由化学分析和光谱数据确定为1,14-二羟基-7,20;19,20-二桥氧-(1α,4α,7α,14R,20R)-贝壳杉烯-16-烯-15-酮(1),和它的同系物kamebakaurene(2)的结构式大体相似.     

β-氰乙基-α-二茂铁邻卤代苄基醚的晶体和分子结构

本文应用X射线单晶衍射方法测定了系列β-氰乙基-α-=茂铁邻卤(氟、氯、溴、碘)代苄基醚的晶体结构, 描述并讨论了由卤原子变更所引起的分子结构差异。结果表明, 取代卤原子种类不同, 导致了该系列化合物分属于两种分子构型。     

二苯基次膦酸晶体和分子结构

二苯基次膦酸[(C₆H₅)₂P(O)OH]属于单斜晶系,单位晶胞中包含四个分子,晶胞参数为a=11.49Å,b=6.09Å,c=15.78Å;β=100°.空间羣为C_2h⁵=P2₁/c.用Patterson及电子密度函数方法获得原子坐标.键长C……C=1.40Å,P—O=1.49Å,P—C=1.81Å.分子之间尚具较强的氢键,O…H—O—2.74Å.     

N1-乙酰基-N3-邻甲苯甲酰基-5-氟脲嘧啶的晶体和分子结构

5-氟脲嘧啶(5-FU)和N₁(2-四氰呋喃)-5-氟脲嘧啶(FT-207.2)在肿瘤的临床实验上,引起了人们极大的兴趣和得到广泛的应用,但它们具有毒性大和对肿瘤的免疫抑制作用,因此,为提高疗效,降低毒性的5-FU衍生物的开发,引起了人们的关心.     

二茂铁金属有机液晶的合成,结构及介晶性研究

我们曾研究了以季铵盐作为相转移催化剂,通过二茂铁的芳基化反应,合成了一系列带活泼官能团的二茂铁衍生物［１］。这些衍生物可作为合成二茂铁非线性光学材料、液晶材料的良好中间体［２－４］。为了探索分子几何结构与介晶性能之间的关系和制备结构新颖、稳定性能好、...     

鹤草酚的晶体结构和分子结构

鹤草酚晶体属三斜晶系,空间群为PI,晶胞参数为a=9.901(3),b=11.195(4),c=11.752(4)Å,α=80.74(3),α=75.66(3),γ=76.46(3)°,晶胞内分子数Z=2.用SyntexP3/R3型四圆衍射仪收集到2891个独立衍射强度.以直接法SHELXTL解出晶体结构.结构参数的修正采用了块对角矩阵最小二乘法,最后得偏离因子R=5.7%.晶胞中含有d-,l-两种对映体分子,它们彼此以I连系组成外消旋体.每分子中的两个六环分别同相邻的氧共面,其双面角为14.2°.两个六环通过碳(sp³)桥相连,并由于形成分子内氢键O-H…O(分别为2.705Å和2.745Å)而限制了自由转动.     

THE CRYSTAL AND MOLECULAR STRUCTURE OF TRIPTONIDE

<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.     

秃毛冬青甲素分子结构及晶体结构的测定

秃毛冬青甲素为一种新木脂类化合物,在氯仿中重结晶得无色透明的六边形晶体,它的分子式为C₁₄H₁₆O₆,分子量280.09,计算密度1.443g/cm³,m.p.195～197℃.     

THE CRYSTAL AND MOLECULAR STRUCTURE OF p-NITROPHENACETURIC ACID

Abstract

The crystal and molecular structure of p-NO₂C₆H₅CH₂CONHCH₂COOH or C₁₀ H₁₁ N₂O₅ has been determined by single crystal x-ray diffraction techniques. The compound crystallizes in the space-group P₂₁. /c with four molecules in a unit cell of dimensions: a = 11.8748(5)Å, b = 11.2732(4)Å, c = 8.8073(5)Å and β = 112.966(4)°. The structure was solved by direct methods and refined to a final value of R = 0.042. The molecule assumes a conformation similar to that found for the analogous side-chain in the penicillin G molecule and hence should be a convenient model system in studying copper catalyzed degradations of penicillin. The hydrogen bonding between the amide oxygen of one molecule to the carboxylic acid proton, 2.67(1)Å, and the amide nitrogen, 2.91(1)A, of another molecule creates a three-dimensional network identical to that found for hippuric acid.     

DETERMINATION AND REFINEMENT OF THE CRYSTAL STRUCTURE OF CHAIDAMUITE

Chaidamuite (ZnFe(SO_4)_2(OH). 4H_2O), which is a new sulphate mineral, belongs to the triclinic system, space group P1, with the cell parameters corrected by the least-squares method: a=7.309(2), b=7.202(2), c=9.691(3), α=89.64(3), β=105.89(3), γ=91.11(2)°, Z=2. The crystal structure has been determined by the Patterson method and Fourier syntheses and refined by the full-matrix least-squares method to an R factor of 0.032, using 2833 independent reflections. In the structure, a zigzag chain consists of [Fe(1)O_5(OH)] and [Fe(2)O_5(OH)] octahedra sharing the OH corners, and an octahedral-tetrahedral chain running parallel to the b axis consists of the zigzag chain of Fe octahedra and (SO_4) tetrahedra sharing four pairs of octahedral corners on either side of the zigzag chains. These chains are cross-linked by the isolated [Zn(1)O_2(H_2O)_4] and [Zn(2)O_2(H_2O)_4] octahedra into corrugated sheets parallel to the (100) plane. Adjacent sheets are hydrogenbonded through water molecules.     

THE PHOTOCHEMISTRY AND CRYSTAL STRUCTURE OF SOLID 1-CHLOROANTHRACENE

Abstract— Although the blue-fluorescent (type A) crystalline modification of lthloro-anthracene is photochemically stable, the green-fluorescent modification (type B) undergoes photodimerisation on exposure to the Hg line at 365 mμ, to produce a different solid modification of the dimer from that precipitated from an exposed soIution.     

黄草灵的晶体结构

黄草灵,H₂NSO₂NHCOOCH₃,是氨基甲酸酯系列除草剂中的一种,商品名为Asulam.其杀草谱广,特别是对防除多年生的深根杂草效果良好.同时它还具有对哺乳动物低毒、在土壤中残效期短以及易被非防除对象的生物体降解等特点.氨基甲酸酯类化合物为内吸传导性除草剂.据文献报道^[1],黄草灵被植物吸收后输送至顶部和芽中。它的主要杀草机理是抑制RNA和蛋白质的合成.有人证明^[2],诱导效应、立体效应、共振效应以及分子的大小等因素都影响氨基甲酸酯类化合物在植物体内被酶水解的速度.我们测定了黄草灵的晶体结构,可为研究其除草机理提供一些资料.     

对—乙酰苯基二茂铁的晶体结构

单取代二茂铁化合物,尤其是单取代芳基二茂铁化合物,当芳基为带有各种不同取代基苯时,中心铁原子的氧化还原电势会产生相应的变化,茂环上屹化学位移也明显地与Hammett常数相关。在对-乙酰苯基二茂铁的电化学研究中已经证明,它的氧化势