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The structure of the title compound, C19H26O2·H2O, was determined by X-rays.M r=304.4, space groupP21,a=10.3113(6),b=10.3978(21),c=7.8710(9) Å, =89.527(9)°,V c=844(1) Å3,Z=2,D x=1.194 Mg m–3. CuK radiation ,(CuK)=5.9 cm,F(000)=332. FinalR factor=0.046 (R w=0.047) for 1002 unique reflections. The structure was solved usingMultan. The water molecule is the hydrogen donor to O(3) and a hydrogen acceptor from the O(17) hydroxyl group. RingA is rather flat relative to the rest of the steroid backbone and the O(3)-plane distance is 1.99 Å.  相似文献   

3.
The structure of the title compound was determined by X-rays:M r =319.4,P212121,a=7.753(3),b=10.566(8),c=20.997(10) Å,Z=4 andD x =1.171 M gm–3. FinalR=0.042 (R w =0.041) for 1814 unique reflections. The water molecule is the hydrogen donor to O3 and O17 and an hydrogen acceptor from the O17 hydroxyl group.  相似文献   

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The crystal structure of progesterone hydroquinone monohydrate was determined by means of X-ray diffraction methods:M r=442.6, orthorhombic,P212121,a=14.680(2),b=22.725(3),c=7.334(1) Å,V a=2446.6(6) Å3,Z=4,D x=1.190 M gm–3, MoK radiation ,(MoK)=0.75 cm–1,F(000)=948. The structure was solved usingMultan;R=0.059,R w=0.059 for 2736 reflections. This progesterone molecule has the most flattenedA ring, relative to the rest of the skeleton, of all progesterone molecules studied so far. Steroid, hydroquinone, and water molecules form, by means of hydrogen bonds, two parallel chains connected with each other by hydrogen bonds.The authors thank Dr. A. Szyczewski for supplying crystals. This research was supported by the project RP.II.10 from the Polish Ministry of National Education and by PHS Grant No. DK26546.  相似文献   

6.
[(H3O)(C14H20O5)2][Me2NH2]2 [PMo12O40] · 2C14H20O5 1 was synthesized from benzo-15-crown-5 and H3PMo12O40·24H2O in N,N-dimethylformamide for the first time. 1 crystallizes in the monoclinic space group C2/c with a = 18.583(4), b = 25.510(5), c = 19.904(4) Å, = 94.66(3)° D c = 2.124 mg/m3 for Z = 4. Refinement based on 7358 observed reflections led to a R1(wR2) = 0.0378(0.0761). The complex cation, [(H3O)(C14H20O5)2]+, exhibits a sandwich structure by hydrogen-bonding in the mean distance of 2.955 Å. The anion, PMo12O40 3–, is a -Keggin structure.  相似文献   

7.

Abstract  

The imidazolyl derived complex N,N′-butylenebis(imidazole):(oxalic acid)0.5 was prepared and structurally characterized by X-ray crystallography. The title compound crystallizes in the triclinic, space group P-1, with a = 4.4373(9) ?, b = 12.882(3) ?, c = 15.319(3) ?, α = 99.91(3)°, β = 94.53(3)°, γ = 98.72(3)°, V = 847.7(3) ?3, Z = 2. Two N,N′-butylenebis(imidazole) and two oxalic acid molecules form an annulus via intermolecular hydrogen bonds, with internal dimensions of about 7.1 × 11.1 ?. Neighboring annuluses were connected by N–H···O and C–H···O interactions to form 1D double chain structure. Adjacent double chains stacked just above each other along the a-axis direction, this arrangement of the double chains leads the extended supramolecular architecture to show a three-dimensional porous network.  相似文献   

8.
Crystals of the hemihydrate of this bile acid are hexagonal, space groupP6522, a=b=13.736(8)Å,c=85.06(6)Å,V=13,899Å3. The asymmetric unit contains two independent steroid molecules and one water molecule, the latter disordered over two nonequivalent positions.Z=12[2(C24H40O5)·1(H2O)],F(000)=5496. Structure solution by direct methods; refinement by least-squares, toR=0.072. The complex hydrogen-bond system comprises: (a) three standard ordered O-HO hydrogen-bonds; (b) what is probably a symmetrically hydrogen-bonded carboxylic acid dimer, with a twofold rotation axisin the plane of the two carboxyl groups; (c) helical hydrogen-bonding chains about each 65 axis, disordered over four possible arrangements. In these helical chains, the six independent hydrogen-bonds can as a group be in either of two systems of nearly equivalent flip-flop arrangements: O-HO OH-O. Each helical system includes water, which can occupy either of two sites; thus, there is further disorder involving two sets of nonequivalent hydrogen-bonds with water as donor and acceptor. Many aggregation features here differ markedly from those in the crystal structures of either anhydrous cholic acid or cholic acid monohydrate.  相似文献   

9.
The X-ray crystal structure of 6-acetoxyprogesterone, C23H32O4, has been determined. This compound crystallizes in space groupP212121 witha=13.195(3),b=15.035(4),c=10.705(3) Å,V=2139.8(9) Å3,M r=372.5,Z=4,D x=1.156g cm–3; MoK radiation (=0.7107 Å),=0.72 cm–1,F(000)=808;R=0.069, andR w=0.052 for 1292 reflections. RingA adopts a normal 1,2-half-chair conformation. The side chain is typical for a 20-ketosteroid conformation.  相似文献   

10.
Abstract A new pyrazine compound, has been synthesised and characterised by single-crystal X-ray diffraction: monoclinic, P21/c with a = 11.0707(3) ?, b = 5.23700(10) ?, c = 16.6997(5) ?, β = 103.5385(16)°, Mr = 376.40, V = 941.30(4) ?3, Z = 2. Each molecule possesses C i symmetry with the two halves of the molecule related by an inversion centre. C–H···π and C=O···π interactions held the molecules together. Index Abstract C–H···π and C=O···π intermolecular interactions in dibenzyl-3,6-dimethylpyrazine-2,5-dicarboxylate Joana A. Silva, Ana C. Santos, Ana T. Marques, Manuela Ramos Silva, Ana Matos Beja, Abílio J. F. N. Sobrala In dibenzyl-3,6-dimethylpyrazine-2,5-dicarboxylate, each molecule possesses C i symmetry. The molecules are assembled in chains via carbonyl···π interactions. Electronic supplementary material The online version of this article (doi: ) contains supplementary material, which is available to authorized users.  相似文献   

11.
Abstract  4-Androstene-3,17-dione was synthesized for its crystallographic analysis and to investigate the role of intra- and intermolecular interactions in steroids. It crystallizes in the orthorhombic space group P212121 with unit cell parameters, a = 7.330(2) ?, b = 13.095(11) ?, c = 16.856(17) ?, V = 1,618(5) ?3 and Z = 4. The structure has been solved by direct methods using X-ray diffraction techniques and the refined final reliability index for the computed structure is 0.033 for 1,655 observed reflections. Two six-membered rings B and C exist in chair conformation while ring A occupies a sofa conformation. The five-membered ring D depicts envelope conformation. The C–H···O intermolecular hydrogen interaction results into a ring like configuration which makes the dimers. Index Abstract   Androgen is the generic term for any natural or synthetic compound, usually a steroid hormone, that stimulates or controls the development and maintenance of masculine characteristics in vertebrates by binding to androgen receptors [1]. Androgens have been used in breast cancer when excision or radiotherapy have failed to control the progress of local recurrent disease. They are also used in case where the primary tumour is inoperable or is unsuited for, or resistant to, radiotherapy. Androgens are also believed to be responsible for linear bone growth in both males and females, probably in conjunction with somatotrophin [2]. In continuation to our work on the single crystal growth of X-ray diffraction quality crystals and crystallographic analysis of steroidal molecules, [3-7] synthesis and crystallographic study 4-androstene-3,17-dione is reported in this paper.  相似文献   

12.
The crystal structure of a unidecahydrated co-complex between two Inosine 5-monophosphate (IMP) and one L-glutamine has been determined at atomic resolution by X-ray crystallographic methods. The crystal belongs to the monoclinic space group P21 with cell dimensions a = 8.690(2), b = 21.900(3), c = 12.370(1) Å, and = 110.59(3)°. This structure reveals the recognition mechanism of glutamine to the nucleotide through direct and water-mediated hydrogen bonds. The phosphate oxygen (O23) seems to prefer the nonspecific interaction with the functional sites of glutamine (NA···O23 = 2.672, OH···O23 = 3.063, OE···O23 = 3.104 Å), whereas the bases prefer specific (N23···O = 2.874 Å) bindings. But here no specific interaction has been observed at N17 and N27, which were observed in serine—IMP complex. However, the solvent mediated N17···OW3···N27 hydrogen bonds for stabilization of the stacked purine bases have been observed as in other aminoacid-nucleotide cocrystals. The striking habit of glutamine to occupy the nearly same region of the nucleotide cocrystal as was found in the serine—IMP complex through substantial replacement of free and bound water molecules, shows certainly the cooperative hydrogen bonding economy of water molecules.  相似文献   

13.
3-Hydroxyandrost-5-en-17-one (C19H28O2.CH3OH) has been prepared for undertaking its crystallographic analysis and to investigate the role of intra- and intermolecular interactions in steroids. The title compound crystallizes in the orthorhombic space group C2221 with unit cell parameters a = 6.7892(17), b = 12.624(2), and c = 41.136(5) Å; V = 3525.7(12) Å3 and Z = 8. The three-dimensional structure has been solved by direct methods. The final reliability index for the computed structure is 0.050 for 1088 observed reflections. Ring A exist in chair conformation, Ring B in half-chair conformation, and the Ring C assumes a distorted chair conformation. The five-membered Ring D adopts half-chair conformation. The A/B ring junction is quasi-trans while as B/C and C/D are trans-fused. The oxygen atom of the solvent molecule (CH3OH) is involved in O–H···O intermolecular interaction.  相似文献   

14.
The X-ray crystal structure of 7-hydroxyflavone monohydrate, C14H10O3 · H2O, is determined. The compound crystallizes in the monoclinic space group, P21/n with a = 3.801(3), b = 19.665(4), c = 16. 039(6), = 93.69(3)°, and = 0.68 mm–1 for Z = 4. The phenyl ring of the flavone moiety is rotated 18.6(1)° out of the penzopyran plane, which is a typical value for flavones. In the crystal lattice, there are wide channels which are lined mainly by C–H groups. The water molecules enclosed in these channels are severely disordered.  相似文献   

15.
The crystal structure of 17-methyltestosterone hemihydrate, C20H30O2·1/2H2O, has been determined:M r =312.5, space groupP21212121,a=6.374(2),b=12.807(2),c=43.398(5)Å,V c =3543(2)Å3,Z=8,D x =1.172 mg–3, CuK radiation ( = 1.54184 Å),(CuK)=5.5 cm–1,F(000)=1376. The structure was solved usingMultan. The final conventionalR=0.053 (R w =0.052) for 3634 reflections. The structure contains two crystallographically independent molecules in the asymmetric part of the unit cell that have almost identical geometry.  相似文献   

16.
利用脒基硫脲和3,5-二羟基苯甲酸制备出了一种新型的加合物(C2H7N4S)+·(C7H5O4)-,用X射线单晶衍射试验方法测定其晶体结构.结果表明,晶体属单斜晶系,P21/n空间群,其中a=0.72303(1)nm,b=1.42970(3) nm,c=1.07991(2)nm,β=91.591(2)°,Z=4,R1=0.0303, wR=0.0823(I>2σ(I)).在标题化合物的晶体结构中,3,5-二羟基苯甲酸通过羧基和羟基的O-H…O氢键头尾相连形成了沿b轴无限延伸的"Z"型链,脒基硫脲通过氢键的缔合和静电相互作用连接3,5-二羟基苯甲酸的"Z"型链构成了3D超分子氢键网络结构.  相似文献   

17.
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   

18.
The crystal and molecular structure of 3,12-dihydroxy-2-morpholino-5-pregnan-20-one, C25H41O4N, has been determined:M r =419.6,P21,a=13.5778(8),b=14.4340(8),c=5.8943(5) Å,=94.32(1)°,V c =1151.9(3) Å3,Z=2,D x =1.21 g cm–3, (CuK) = 1.5418 Å, =5.6 cm–1,F(000)=460,R=0.039,R w =0.040 for 2421 unique observed reflections. All six-membered rings have chair conformations, and theD ring has a 13-envelope conformation. The progesterone side chain has an unusual conformation, and the C16-C17-C20-O20 torsion angle, which defines the conformation, is –152.6(3)°. The unusual conformation seems to be forced by the intramolecular hydrogen bond between the hydroxyl group at C12 and the O20 atom from the side-chain.  相似文献   

19.
The crystal and molecular structures of the alkaloid Royline {(1α,6β,14α, 16β)-20-ethyl-4-hydroxymethyl)-1,6,14,16-tetramethoxyaconitane-7,8-diol} with a water molecule has been determined by X-ray diffraction analysis. The compound crystallizes in the space group P21 with the unit cell parameters a = 10.985(1) Å, b = 7.898(1) Å, c = 14.956(1) Å, β = 102.96(1)°, V = 1264.52 Å3, Z = 2, λMoK α = 0.71073 Å, and R = 0.033 for 2067 observed reflections. Rings A, B, and C adopt a chair conformation, ring D is a half-boat, ring E is a half-chair, and ring F is in an envelope conformation with C(14) at the flap. Molecules are linked together in the crystal by hydrogen bonds.  相似文献   

20.
顾梅  钟国清 《人工晶体学报》2013,42(6):1241-1246
以Bi(NO3)3·5H2O、2-吡啶甲酸和2,2'-联吡啶为原料,合成了配合物[Bi(C10H8N2)(C5H4NCOO)(NO3)2]·0.5H2O,并采用元素分析、红外光谱(FT-IR)、热重分析(TG-DSC)、X射线粉末衍射(XRD)和荧光光谱对其组成和结构进行了表征.结果表明,该配合物具有荧光性质,且Bi3+与2-吡啶甲酸中的两个羧基O原子、2,2'-联吡啶的2个N原子及两个NO3-形成六配位螯合物.在空气中其热分解包括失去结晶水、配体的逐步挥发与氧化分解过程,550℃后完全形成Bi2O3.对其X射线粉末衍射数据进行指标化计算证实该配合物晶体结构属于单斜晶系,晶胞参数为:a=1.810 nm,b=1.285 nm,c =1.214 nm,β=88.83°.  相似文献   

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