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1.
Preparation and crystal structure of spiro(5,7-dimethoxy-1(1H)oxo-2-benzopyran-3(4H),1′-cyclohexane)
V. K. Gupta D. I. Brahmbhatt U. R. Pandya S. Goswami 《Journal of chemical crystallography》2005,35(4):275-279
Spiro(5,7-dimethoxy-1(1H)oxo-2-benzopyran-3(4H),1-cyclohexane) (C16H20O4) was prepared by alkylation of o-lithio 3,5-dimethoxy-N-methyl benzamide with methylene cyclohexane oxide followed by alkaline hydrolysis and its crystal structure was determined by X-ray crystallographic techniques. The compound crystallizes into monoclinic space group P21/c with unit cell parameters: a = 11.914(3) Å, b = 9.861(3) Å, c = 12.508(7) Å, = 91.34(3), Z = 4. The structure has been solved by direct methods and refined to R = 0.039 for 1870 observed reflections. The heterocyclic ring adopts distorted sofa conformation while cyclohexane ring assumes a highly symmetric
chair conformation. The dihedral angle between the mean planes of isocoumarin nucleus and cyclohexane ring is 105.51(5). Molecules are held together in the crystal by C=H ... O hydrogen bonds. 相似文献
2.
M. Soriano-Garcia A. Rodriguez-Romero F. Walls R. Toscano R. Villena Iribe 《Journal of chemical crystallography》1991,21(6):681-685
C22H28N2O3 is monoclinic,P21. Unit-cell dimensions at 293 K area=10.023(5),b=6.615(3),c=14.749(6) Å,=91.41(4)°,V=978(1) Å3,D
c
=1.25 g cm–3, andZ=2. The structure has been determined from single-crystal data collected with a four-circle diffractometer and refined from 1421 reflections toR=0.057. The structural features determined from chemical and spectroscopic studies are confirmed and extended. The stereochemistry at C(4) and C(18) is 4S and 18S. The indole ring is not planar and the seven-membered nitrogen-containing ring adopts a distorted-chair conformation. The angle between the normals to the planes of the indole and sevenmembered rings is 15.2(1)°, while the C(5)-N(6)-C(19)-C(2) atoms of the central axis of the iso-quinuclidine tricyclic structure is 69.1(1)°. The molecules in the crystal are held together by a hydrogen bond, a C-HO contact, and van der Waals interactions. 相似文献
3.
Simon G. Bott Kaiyuan Yang Michael G. Richmond 《Journal of chemical crystallography》2003,33(7):585-588
The structure of (5S)-3,4-dichloro-5-menthoxy-2(5H)-furanone is reported. The title compound crystallizes in the monoclinic space group P21: a = 6.650(2) Å, b = 8.038(3) Å, c = 14.858(8) Å, = 97.01(3), V = 788.3(6) Å3, Z = 2, R = 0.0718, R
w = 0.0795 for 735 observed reflections with I > 3 (I), and the absolute configuration at C-5 of the furanone ring is shown to be (S). 相似文献
4.
The crystal structure and the absolute configuration of the title compound has been determined from single-crystal X-ray diffraction data. The monoclinic unit cell (space group P21) witha=11.514(2),b=8.288(1),c=13.749(2) Å, =99.69(1)° andZ=4 contains two crystallographically independent molecules. The configuration at the sulfur atom in both molecules is S. A large lability of the methoxysulfinylacetic group conformation and configuration is observed. The conformations and S–Csp
3–Csp
2
(phen) bond angles of this group in two independent molecules are distinctly different. The comparison of the investigated compound with the literature data of related molecules is given. 相似文献
5.
M. Soriano-García R. A. Toscano A. Sánchez L. Rodríguez-Hahn 《Journal of chemical crystallography》1986,16(4):507-517
C34H43O16N·CH3OH·H2O is monoclinic,C
2
2
-P21. Unit cell dimensions at 293 K area=9.159(3),b=17.017(5),c=13.675(5) Å,=109.49(2)°,V=2009(1) Å3,D
c
=1.28 g cm–3, andZ=2. The structure has been determined from single-crystal data collected with a four-circle diffractometer and refined from 2367 reflections down toR=0.064 andR=0.082. The structural features determined from chemical and spectroscopic studies are confirmed and extended. The absolute configuration was determined by comparison with known absolute stereochemistry of the bromoacetylneoevonine monohydrate. The acanthothamine molecule is an evonine and neoevonine analogue showing an epimeric configuration at C(17) of the evoninic acid residue. The A and B rings adopt chair conformations. The C ring has a half-chair conformation. The crystal structure is stabilized by a three-dimensional network of hydrogen bonds and a number of intramolecular C-HO and C-HN interactions. 相似文献
6.
J. N. Lisgarten B. S. Potter C. Bantuzeko R. A. Palmer 《Journal of chemical crystallography》1998,28(7):539-543
The crystal and molecular structure of the antimalarial compound Artemisinin (formerly known as Qinghaosu), C15H22O5 has been determined by direct methods. Crystals are orthorhombic colorless needles, space group P212121, Z = 4. D
c = 1.299 g cm –3, with unit cell parameters a = 6.3543(9), b = 9.439(3), c= 24.066(4) Å. The molecule incorporates a fused ring system containing a six-membered ring C which includes an oxygen bridge and a peroxy-bridge. The ring C has a distorted boat conformation and the C - O - O - C torsion angle is 47.8(2)°. Rings A and D have symmetrical chair and distorted chair conformations, repectively. Ring junctions A/B, A/D, and C/D are cis, junction B/D is trans. All inter-molecular contacts are van der Waals. The absolute configuration of Artemisinin was determined from the refined value of the Flack x parameter. [The atomic coordinates given in a previous structure analysis, Crystal Structure and Absolute Configuration of Qinghaosu, Qinghaosu Research Group, Institute of Biophysics, Academica Sinica, Scientia Sinica, Vol. XXIII No. 3, 380 (1980), do not display the molecule in its absolute configuration.] 相似文献
7.
Balawant S. Joshi Haridutt K. Desai Sudhakarrao Bhandaru S. William Pelletier M. Gary Newton Andrew J. Kay 《Journal of chemical crystallography》1993,23(11):877-883
The crystal and molecular structure of the norditerpenoid alkaloid 1-epi-delphisine (5), C28H43NO8, M
r
521.66, has been confirmed by as X-ray diffraction study using the SIR 88 analysis program. The alkaloid crystallizes in the space groupP21 with cell parameters:a=11.853(1)Å,b=10.511(1)Å,c=11.854(1)Å,=112.58(1),V=1363.61(0)Å3,Z=2,D
calc=1.27 g/cm3, (CuK)=1.54184 Å, (CuK=7.2 cm–1,F(000)=564, temperature 23°C,R=0.052, for 2907 reflections. Ring A of 1-epi-delphisine exists in a chair conformation. By comparison, delphisine which bears a C-1 hydroxyl group, has ring A in a boat conformation stabilized by an intramolecular N----H-O hydrogen bond. Ring D of both of these alkaloids exists in a boat form. Unambiguous proton and carbon-13 nmr assignments for delphisine, 1-epi-delphisine and delphinine have been made by a detailed analysis of the DEPT, COSY, HETCOR, COLOC, DIFNOE, and selective INEPT nmr techniques.Dedicated to the memory of Dr. K. Krishna Bhandary (1946–1992). 相似文献
8.
1,4-Di-[2-phenyl-1-diazenyl]perhydro-1,4-diazepine (1) has been synthesized by reaction of benzenediazonium chloride with homopiperazine (perhydro-1,4-diazepine). The crystal structure of 1 has been determined by single crystal X-ray diffraction analysis. The bis-triazene (1) adopts an extended conformation which precludes any close intramolecular interaction of the phenyl rings. The heterocyclic seven-membered ring adopts a chair conformation, with the triazene side chains occupying alternate axial and equatorial positions consistent with cis-geometry. Internal torsion angles of the seven-membered ring have been measured. The crystal packing is determined by short contacts between C=H groups of phenyl rings and nitrogens of triazene moieties and by van der Waals interactions, with no evidence for intermolecular – interactions. This work establishes the structure of the product of diazonium coupling with homopiperazine as 1,4-di[(E)-2-phenyl-1-diazenyl]perhydro-1,4-diazepine. Crystal data: 1 C17H20N6, monoclinic, space group P21/n, a = 9.1838(5) Å, b = 12.1095(6) Å, c = 15.0081(8) Å, = 101.320(2), V = 1636.6(2) Å,3 for Z = 4. 相似文献
9.
The crystal structure of 6,13-bis-(N,N-dimethylcarbamoyl)thioquinanthrene 3 has been determined as monoclinic, with space group P2(1)/c with lattice parameters a = 10.044(2) Å, b = 21.385(4) Å, c = 10.889(3) Å, = 102.92(3)°, Z = 4 and Dcalc = 1.342 Mg/m3. The middle 1,4-dithiin ring in the title compound 3, C24H20N4O2S2 is in a boat conformation with the dihedral angle between the planes of the aromatic rings 132.45(8)°. 相似文献
10.
M. Soriano-García F. Walls A. Rodríguez I. López Celis 《Journal of chemical crystallography》1988,18(2):197-206
C19H24N2 is orthorhombic,D
2
4
-P212121. Unit cell dimensions at 293 K area=10.346(7),b=10.464(3),c=29.083(10)Å,V=3149(4) Å3,D
c
=1.18 g cm–3, andZ=8. The structure has been determined from single-crystal data collected with a four-circle diffractometer and refined from 1968 reflections down toR=0.045 and
R=0.047. The structural features determined from chemical and spectroscopic studies are confirmed and extended. There are two crystallographically independent molecules (A and B). In both A and B molecules the indole ring system is planar and attached to a seven-membered nitrogen-containing ring with a distorted-chair conformation. The indole and seven-membered rings lie close to the same plane [dihedral angles are 6.6(5) and 4.1(5)° for the A and B molecules, respectively], while the C(5)-N(6)-C(19)-C(2) atoms of the central axis of theiso-quinuclidine tricyclic structure are almost perpendicular to seven-membered ring [dihedral angles are 84.7(5) and 87.9(5)° for the A and B molecules, respectively]. The A and B molecules in the crystal are packed at normal van der Waals distances. 相似文献
11.
José Castañeda-Acosta Howard G. Pentes Frank R. Fronczek Nikolaus H. Fischer 《Journal of chemical crystallography》1999,29(9):1057-1059
The sesquiterpene lactone isoconfertiflorin, C17H22O5, 1, crystallizes in trigonal space group P31 with a = 10.4498(5), c = 12.7516(8) Å, V = 1205.9(2) Å3, and Z = 3. It differs from confertiflorin in having an endocyclic C=C bond in the lactone ring, which carries an exocyclic methyl group. The seven-membered ring adopts an approximate twist-chair conformation with C10 lying in the local two-fold axis, and asymmetry parameter C2 = 5.8°. The cyclopentanone ring has the half-chair conformation with C4 on the local two-fold axis, and C2 = 0.9°. The lactone ring is almost planar with maximum deviation 0.014(2) Å. Both methyl groups on the 7-membered ring are –oriented. The acetyl group at C8 has an orientation. 相似文献
12.
G. Admiraal J. M. M. Smits Paul T. Beurskens F. M. C. Leemhuis L. Thijs B. Zwanenburg 《Journal of chemical crystallography》1996,26(4):305-308
The stereogeometry and absolute configuration of the title compound has been proved by an X-ray diffraction analysis. Crystal data: monoclinic, P21,a=7.7976(2),b=7.8288(2),c=8.9791(4) Å, =90.331(4)o, Z=2. The crystal structure has been solved by vector search methods and refined toR=0.042 for 1798 observed reflections. 相似文献
13.
Xiangshan Wang Daqing Shi Shujiang Tu Changsheng Yao 《Journal of chemical crystallography》2004,34(2):159-165
The title compounds 2-amino-3-cyano-4-(2-chlorophenyl)-1,4-dihydro-2H-pyrano[3, 2-h]quinoline 1 (C19H12ClN3O, M
r = 333.77) and 2-amino-3-cyano-4-(2-chlorophenyl)-8-(2-chlorobenzylidene)-1,4,5,6,7,8-hexahydrobenzo[b]pyran 2 were synthesized and crystallized. The crystals of compound 1 are triclinic, space group P-1, a = 7.488(2), b = 9.127(3), c = 12.252(3) Å, = 73.58(2), = 78.38(2)°, = 75.39(2), Z = 2, V = 769.5(4) Å3; The compound 2 crystallizes in space group P21/n, with cell parameters a = 13.582(2), b = 8.974(1), c = 16.960(2) Å, = 103.34(1)° and D
calc = 1.352 g/cm–3 for Z = 4. X-ray analysis reveals that atoms C(1)—C(5) and O form a pyran ring in compound 1, which adopts half-chair conformation. In compound 2 the atoms C(12)—C(16) and O form a pyran ring which adopts boat conformation, another six-membered ring (C(8)—C(13)) adopts a half-chair conformation. In addition, there are intermolecular hydrogen bonds in the crystal structures 1 and 2. 相似文献
14.
Crystal and molecular structure of delsoline 总被引:4,自引:0,他引:4
Balawant S. Joshi Haridutt K. Desai S. William Pelletier M. Gary Newton 《Journal of chemical crystallography》1992,22(4):477-483
The crystal and molecular structure of the diterpenoid alkaloid delsoline (1) C25H41NO7, Mr 467.61, has been determined by an X-ray analysis. The X-ray crystal structure which could not be solved earlier withMultan, has now been solved using the SIR 88 analysis program. The compound crystallizes in the space groupP212121 with cell parameters:a=12.529(2),b=13.118(1),c=14.231(6)Å,V=2339(1)Å3,Z=4,D
calc=1.33 g/cm–3, (CuK)=1.54184 Å,(CuK
)=7.4 cm–1,R/R
w
=0.068/0.040 for 2539 reflections. The A ring of delsoline exists in the boat conformation stabilized by an intramolecular N---H-O hydrogen bond. Ring D also is in a boat form. Unambiguous proton and carbon-13 nmr assignments have been made by a detailed analysis of the DEPT, COSY, NOESY, and HETCOR nmr spectra. 相似文献
15.
Linomide [N-methyl-N-phenyl-1,2-dihydro-4-hydroxy-1-methyl-2-oxo-quinoline-3-carboxamide] is a new immunomodulator from Phamacia Laboratories, Helsingborg, Sweden. Linomide (LS-2616) has delayed hypersensitivity in rat skin, potentiates mouse natural killer cell activity, and stimulates polyclonal T-cell activation. It has been shown that LS-2616 abolishes the effects of continuous cyclosporine treatment in experimental models. Crystal structure of LS-2616 has been undertaken as a first step in the establishment of a possible structure–function relationship for the drug. Crystals of LS-2616 (C18H16N2O3) obtained from methylene chloride are monoclinic, of space group P21/a with the following crystallographic parameters: a = 8.793(1) Å, b = 22.349(3) Å, c = 7.808(1) Å, = 92.96(1)°, V = 1532.3(6) Å3, obs = 1.34 Mg/m3, calc = 1.337 Mg/m3, and Z = 4. The structure was solved with CAD-4 data using MULTAN programs and refined to a final R value of 0.041. The N-methyl carboxamide is in the cis configuration and is turned away from the quinoline ring by 87°. FK506 is a novel 23-membered macrolide lactone which is currently used for bone marrow and organ transplantations. The crystal structure of FK506 has been published. The absolute configuration of FK506 was established as a cis-amide which contains a L-pipecolic acid moiety. Preliminary modeling studies of FK506 with LS-2616 revealed that this cis conformation for the N-methyl carboxamide leads to a lower binding energy than the corresponding trans conformation. The plane of the phenyl group is inclined by 95° to the carboxamide plane. The molecule has the familiar herring-bone type of packing, characteristic of the polyphenyl molecules, stabilized by O–H O and C–H O hydrogen bonds involving the hydroxyl group and the ketone substituents on the quinoline ring and the N-methyl group of the carboxamide. 相似文献
16.
Norman S. Bhacca Frank R. Fronczek Andrzej Sygula 《Journal of chemical crystallography》1996,26(7):483-487
The crystal structure of an orthorhombic polymorph of the title compound, crystallized by sublimation, has been determined. Dehydroepiandrosterone, C19H28O2, space groupP212121 witha=6.6408(4)b=11.4423(11)c=22.085(2)Å,V=1678.2(4)Å3,Z=4. The structure was refined toR=0.051 for 2645 observed reflections. The conformation of the molecule is similar to that found in other polymorphs and solvates, with a chair A ring, an 8, 9 half-chair B ring, a chair C ring, and a 14 envelope D ring. Molecules are linked in chains by OH...O hydrogen bonds involving the carbonyl oxygen atom. The O...O distance is 2.855(3) Å, and the angle about H is 171(2)o. 相似文献
17.
Yohimbine (C21H26N2O3) is an important indole alkaloid found in the Indian snake rootrauwolfia serpentina, and is very closely related to reserpine. Yohimbine hydrochloride (C21H27ClN2O3) is orthorhombic:P212121,a = 11·54,b = 24·88,c = 7·00 Å,Z = 4. X-ray diffraction data to a Bragg angle of 80 ° were collected on a G.E. diffractometer using CuK radiation. The structure was solved by direct methods, and refined to a reliability index of 9·9 % by the block-diagonal least-squares method. Yohimbine has a ring system very similar to that of reserpine, though the conformations of the ringsC andD about the C—N bond are different in the two molecules. The absolute configuration of the molecule, determined by X-ray anomalous scattering, confirms the 3, 15, 20 configuration assigned earlier by conformational analysis. 相似文献
18.
Judith H. Everett Colin D. Reynolds Catherine A. Sparks Walter Pangborn Patrick D. Bailey Zbigniew Dauter Madeleine Helliwell Sean P. Hollinshead 《Journal of chemical crystallography》1990,20(2):109-115
(1R,3S)-2-Benzyl-3-methoxycarbonyl-1-methylcarboxymethyl-1,2,3,4-tetrahydro-9H-pyrido [3,4-b] indole, C23H24N2O4, was synthesized by a modified Pictet-Spengler reaction, and its crystal and molecular structure determined by single crystal X-ray diffraction methods. The crystals are monoclinic:P21 (No. 4),a=11.336(1),b=8.919(1),c=10.314(1)Å,=100.81(1)°,Z=2. The structure has been solved by direct methods, and refined toR=0.041 for 2203 observed reflections. The six-membered heterocyclic ring is in a half-chair conformation, and the substituents at C(3) and C(5) occupy axial and equatorial positions respectively. The CH2Ph group attached to N(4) is in the generally less favoured axial position. The nitrogen atom of the indole system forms an intermolecular hydrogen bond with the carbonyl oxygen of the CH2CO2 Me group, the NO distance being 2.995(3)Å. 相似文献
19.
Ian R. Pottie C. V. Krishnamohan Sharma Keith Vaughan Michael J. Zaworotko 《Journal of chemical crystallography》1998,28(1):5-10
The crystal and molecular structure of 1,2-bis-{1-(2-cyanophenyl)-3-methyltriazen-3-yl-}ethane (1) and 1,2-bis-{1-(2-methoxyphenyl)-3-methyltriazen-3-yl-}ethane (2) have been determined by single crystal X-ray diffraction analysis. Bis-triazene (1) exists as the staggered conformation in the solid state, with an anti-anti configuration around the N2–N3 bond of the triazene units, whereas 2 assumes a gauche conformation with the syn-syn configuration in the triazene units. Crystal data: 1 C18H18N8, triclinic, space group P –1, a = 6.108(2), b = 8.118(3), c = 9.600(4)Å, = 101.37(7)°, = 96.47(7)°, = 102.71(5)°, V = 449.1(3)Å3, Z = 2; 2 C18H24N6O2, monoclinic, space group P 21/n, a = 13.119(5), b = 7.745(2), c = 19.201(2)Å, = 96.47(7)°, V = 1910.3(9)Å3, Z = 4. 相似文献
20.
Ilia A. Guzei 《Journal of chemical crystallography》2004,34(3):181-184
Synchrotron data allowed the crystal structure determination of 4,4,6,6-tetraphenylcyclohex-2-en-1-one (1). The cyclohexenone ring is in a half-chair conformation 3H2violating the planarity of a conjugated -system. The geometry of 1 optimized with semiempirical and density functional theory calculations is in good agreement with the experimental data. Compound 1 crystallizes in triclinic space group
with unit cell parameters a = 9.7995(19) Å, b = 10.5263(32) Å, c = 12.2001(37) Å, = 96.916(10)°, = 112.971(10)°, = 102.589(10)°, V = 1100.86(17) Å3, and Z = 2. 相似文献