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1.
R. Hema V. Parthasarathi S. Thamotharan S. Dubey D. P. Jindal 《Acta Crystallographica. Section C, Structural Chemistry》2003,59(4):o213-o215
In the title compound, 4‐(3β‐hydroxy‐17‐oxoandrost‐5‐en‐16‐ylidenemethyl)benzonitrile, C27H31NO2, rings A and C of the steroid nucleus are in chair conformations. The central six‐membered ring B is in an 8β,9α‐half‐chair conformation, while the five‐membered ring D adopts a 13β,14α‐half‐chair conformation. The cyanobenzylidene moiety has an E configuration with respect to the carbonyl group at position C17. The dihedral angle between the planes of the steroid nucleus and the cyanobenzylidene moiety is 22.61 (15)°. Intermolecular O—H⃛N hydrogen bonds formed between the hydroxyl group of the steroid and the N atom of the cyanobenzylidene moiety of symmetry‐related molecules link the steroid molecules into chains which run parallel to the b axis. 相似文献
2.
Daniel Vega Daniel Fernndez Javier A. Ellena 《Acta Crystallographica. Section C, Structural Chemistry》2001,57(9):1092-1094
The title compound, raloxifene hydrochloride, C28H28NO4S+·Cl?, belongs to the benzothiophene class of antiosteoporotic drugs. In the molecular cation, the 2‐phenol ring sustains a dihedral angle of 45.3 (1)° relative to the benzo[b]thiophene system. The benzo[b]thiophene and phenyl ring planes are twisted with respect to the carbonyl plane, with the smallest twist component occurring between the phenyl and carbonyl planes. The N atom bears the positive charge in the molecular cation and the piperidine ring adopts an almost perfect chair conformation. The Cl? anion is involved in the formation of N—H?Cl and O—H?Cl intermolecular hydrogen bonds, which lead to the formation of a layer of molecular cations. 相似文献
3.
Abdurrahman engül Nevzat Karaday Orhan Büyükgüngr 《Acta Crystallographica. Section C, Structural Chemistry》2004,60(7):o507-o508
Molecules of the title compound, C12H12N6, contain both a diimine linkage and an N—N bond, and assume a planar structure. The compound lies about an inversion centre and there are three intramolecular C—H⋯N hydrogen bonds. 相似文献
4.
L. C. R. Andrade J. A. Paixo M. J. M. de Almeida R. M. L. M. Martins H. I. M. Soares G. J. R. Morais M. J. S. M. Moreno M. L. S e Melo A. S. Campos Neves 《Acta Crystallographica. Section C, Structural Chemistry》2001,57(5):587-589
The title compound, C23H32O4, has a 3β configuration, with the epoxy O atom at 16α,17α. Rings A and C have slightly distorted chair conformations. Because of the presence of the C5=C6 double bond, ring B assumes an 8β,9α‐half‐chair conformation slightly distorted towards an 8β‐sofa. Ring D has a conformation close to a 14α‐envelope. The acetoxy and acetyl substituents are twisted with respect to the average molecular plane of the steroid. The conformation of the molecule is compared with that given by a quantum chemistry calculation using the RHF–AM1 (RHF = Roothaan Hartree–Fock) Hamiltonian model. Cohesion of the crystal can be attributed to van der Waals interactions and weak intermolecular C—H?O interactions, which link the molecules head‐to‐tail along [101]. 相似文献
5.
R. Hema V. Parthasarathi S. Thamotharan S. Dubey D. P. Jindal 《Acta Crystallographica. Section C, Structural Chemistry》2002,58(7):o421-o422
In the title compound, C31H40N2O·H2O, the outer two six‐membered rings are in chair conformations, while the central ring is in an 8β,9α‐half‐chair conformation. The five‐membered ring adopts a 13β‐envelope conformation and the cyanobenzylidene moiety has an E configuration with respect to the hydroxyl group at position 17. The steroid nuclei are linked by intermolecular O—H?O and O—H?N hydrogen bonds to form a molecular network. The molecular packing has an interesting feature, with the steroids aligned parallel to the b axis, forming a closed loop through hydrogen bonds linked via water molecules. 相似文献
6.
G. Vasuki V. Parthasarathi K. Ramamurthi D. P. Jindal S. Dubey 《Acta Crystallographica. Section C, Structural Chemistry》2001,57(9):1062-1063
The title compound, C25H31NO2·H2O, has the outer two six‐membered rings in chair conformations, while the central ring is in an 8β,9α‐half‐chair conformation. The five‐membered ring adopts a 13,14‐half‐chair conformation. The pyridylmethylene moiety has an E configuration with respect to the carbonyl group at position 17. The structure is stabilized by intermolecular O—H?N and O—H?O hydrogen bonds. 相似文献
7.
J. I. F. Paixo J. A. R. Salvador J. A. Paixo A. Matos Beja M. Ramos Silva A. M. d'A. Rocha Gonsalves 《Acta Crystallographica. Section C, Structural Chemistry》2004,60(1):o72-o74
In the title compound, C21H30O3, a potential inhibitor of aromatase, all rings are fused trans. Rings A and C have chair conformations which are slightly flattened, whereas the conformation of ring B is close to a half‐chair. Ring D has a 14α‐envelope conformation. The steroid nucleus has a small twist, as shown by the C19—C10⋯C13—C18 (steroid numbering) torsion angle of −6.9 (3)°. Ab initio calculations of the equilibrium geometry of the molecule reproduce this small twist, which appears to be due to the conformation of ring B rather than to packing effects. 相似文献
8.
S. Thamotharan V. Parthasarathi Ranju Gupta D. P. Jindal Anthony Linden 《Acta Crystallographica. Section C, Structural Chemistry》2004,60(6):o405-o407
The asymmetric unit of the title compound, C25H30FN3O·0.5CH3OH, contains four symmetry‐independent steroid and two methanol molecules. The conformations of the independent steroid molecules are very similar. Intermolecular O—H⋯O hydrogen bonds create two independent chains, each of which links two of the independent steroid molecules plus one methanol molecule via a co‐operative O—H⋯O—H⋯O—H pattern. Intermolecular C—H⋯O and C—H⋯F interactions are also observed. 相似文献
9.
Mohamed El Kodadi Abdelkrim Ramdani Malek Fouad Driss Eddike Monique Tillard Claude Belin 《Acta Crystallographica. Section C, Structural Chemistry》2005,61(12):o735-o737
The crystal structure of the title compound, C18H23N5O·H2O, shows molecules containing a phenol group linked perpendicularly to a roughly planar fragment comprising two pyrazole rings. Molecules are stacked perpendicular to the [101] direction, with their phenol groups disposed alternately. The molecular packing in the crystal is stabilized by hydrogen bonding involving water molecules. 相似文献
10.
Tuncay TuncÛ Musa Sar Rahmi Yagbasan Habibe Tezcan Ertan SÛahin 《Acta Crystallographica. Section C, Structural Chemistry》2003,59(4):o192-o193
Molecules of the title compound (alternative name p‐methoxybenzaldehyde 2‐pyridylhydrazone), C13H13N3O, adopt an E configuration about the azomethine C=N double bond. Molecules are almost planar, the dihedral angle between the pyridine and methoxyphenyl rings being only 6.19 (12)°. Pairwise N—H⃛N hydrogen bonds [R(8) in graph‐set notation] link centrosymmetrically related molecules into discrete pairs. 相似文献
11.
Jrg Saßmannshausen Jrg Rust Richard Goddard 《Acta Crystallographica. Section C, Structural Chemistry》2000,56(6):e236-e237
The title compound, [Zr(C7H7)3(C15H17)], (I), crystallizes from light petroleum with two independent molecules in the asymmetric unit. Whereas in the parent molecule, Zr(η5‐C5H5)(CH2Ph)3, all three Zr—CH2Ph angles are equal, in (I), they differ significantly. In spite of their different environments, both independent molecules in (I) exhibit a small, an expected, and a large Zr—CH2Ph angle. The angles are similar to those of the closely related tribenzyl[η5‐(benzyldimethylsilyl)cyclopentadienyl]zirconium complex. The smallest Zr—CH2Ph angle and the consequently relatively short Zr?Cipso distance are indicative of η2‐bonding of the benzyl group. 相似文献
12.
S. Thamotharan V. Parthasarathi S. Dubey D. P. Jindal Anthony Linden 《Acta Crystallographica. Section C, Structural Chemistry》2004,60(2):o110-o112
In the title compound, C29H36O2, the outer cyclohexene ring of the steroid nucleus has a conformation that lies about half‐way between a half‐chair and an envelope, while the central and outer cyclohexane rings of the steroid nucleus have slightly distorted chair conformations. The steroidal cyclopentane ring adopts a 13β,14α‐half‐chair conformation. The benzylidene moiety has an E configuration with respect to the carbonyl group on the cyclopentane ring. The dihedral angle between the mean planes of the steroid nucleus and the benzylidene moiety is 35.54 (9)°. The packing of the molecules is assumed to be dictated mainly by weak intermolecular C—H⋯O interactions. 相似文献
13.
Simon J. Coles David Douheret Michael B. Hursthouse Jeremy D. Kilburn Sara Rossi 《Acta Crystallographica. Section C, Structural Chemistry》2000,56(5):e224-e226
Compounds (I), C14H20N2O4S, and (II), C12H14N2O3S2, are two minor products of the same reaction. Both structures contain identical ester functionalities in similar orientations. Both independent molecules of (I) contain an ethoxycarbothioylamine moiety, whilst (II) possesses a novel exocyclic thione system fused with a pyridine ring. 相似文献
14.
Alexander J. Blake Peter Hubberstey Alexander D. Mackrell Claire Wilson 《Acta Crystallographica. Section C, Structural Chemistry》2003,59(6):o293-o297
The trans–trans conformations adopted by the derivatized bis(bidentate) chelating N4‐donor ligand 3,6‐bis(pyrazol‐1‐yl)‐4‐[2‐(4‐thiamorpholino)ethanesulfanyl]pyridazine, C16H19N7S2, and an intermediate in its formation, 3,6‐dichloro‐4‐[2‐(4‐thiamorpholino)ethanesulfanyl]pyridazine, C10H13Cl2N3S2, contrast with the cis–cis conformation found previously for 3,6‐bis(thiophen‐2‐yl)pyridazine [Ackers, Blake, Hill & Hubberstey (2002). Acta Cryst. C 58 , o640–o641], which places all four heteroatoms on the same side of the molecule. 相似文献
15.
Huub Kooijman Anthony L. Spek Marcel Hoogenraad Elisabeth Bouwman Jaap G. Haasnoot Jan Reedijk 《Acta Crystallographica. Section C, Structural Chemistry》2002,58(7):m390-m392
The title compound, tris[2‐(4,5‐dihydrooxazol‐2‐yl‐κN)phenolato‐κO]iron(III), [Fe(C9H8NO2)3], is disordered over a non‐crystallographic twofold rotation axis perpendicular to the crystallographic threefold rotation axis. The disorder can be a pure rotational disorder of an iron complex in the facial configuration, or the consequence of a mixture of facial and meridional configurations. In the latter case, at least 25% of the iron complexes must adopt the facial configuration in order to obtain the disorder ratio observed in the crystal. 相似文献
16.
Yavuz Kysal amil Ik Meri Kksal Hakk Erdgan Nesrin Gokhan 《Acta Crystallographica. Section C, Structural Chemistry》2004,60(4):o232-o234
The title compounds, both C19H20FN3O2, contain essentially planar benzoxazolinone ring systems, within which the C—N bond distances and angles do not differ significantly between the two compounds. In both cases, the piperazine ring adopts an almost perfect chair conformation and the benzoxazolinone ring system lies nearly perpendicular to it. The structures contain intermolecular C—H⋯O contacts, and the interactions between the benzoxazolinone and fluorophenylpiperazine portions of the molecules are segregated. 相似文献
17.
S. Thamotharan V. Parthasarathi Ranju Gupta D. P. Jindal Anthony Linden 《Acta Crystallographica. Section C, Structural Chemistry》2004,60(2):o161-o162
In the title compound, C23H31N3O3, the outer cyclohexane rings have chair conformations, while the central cyclohexene ring adopts a half‐chair conformation. In the solid state, intra‐ and intermolecular C—H⋯N interactions are observed. 相似文献
18.
Vladimir N. Nesterov Tatiana V. Timofeeva Sergey S. Sarkisov Alexander Leyderman Charles Y.‐C. Lee Mikhail Yu. Antipin 《Acta Crystallographica. Section C, Structural Chemistry》2003,59(11):o605-o608
The structures of 3,5‐bis[4‐(diethylamino)benzylidene]‐1‐methyl‐4‐piperidone, C28H37N3O, (I), and 3,5‐bis[4‐(diethylamino)cinnamylidene]‐1‐methyl‐4‐piperidone, C32H41N3O, (II), have been characterized. Because of conjugation between donor and acceptor parts, the central heterocycles (including the carbonyl group) in (I) and (II) are flattened and exhibit a `sofa' conformation, with a deviation of the N atom from the planar fragment. The dihedral angles between the planar part of the heterocycle and the two almost flat fragments that include a phenyl ring and bridging atoms are 23.2 (1) and 11.2 (1)° in (I), and 11.8 (1) and 8.7 (2)° in (II). One‐ and two‐photon absorption of light and the fluorescence of (I) and (II) have also been characterized. 相似文献
19.
Lee J. Higham P. Gabriel Kelly Helge Müller‐Bunz Declan G. Gilheany 《Acta Crystallographica. Section C, Structural Chemistry》2004,60(5):o308-o311
The Ramirez ylide undergoes electrophilic substitution with dialkyl acetylenedicarboxylates, yielding a mixture of the Z and E adducts. The crystal structure analyses of the two adducts formed using dimethylacetylene, viz. dimethyl (E)‐ and (Z)‐1‐[2‐(triphenylphosphoranylidene)cyclopentadien‐1‐yl]ethylenedicarboxylate, both C29H25O4P, explain an unusual chemical shift observed for the vinyl H atom of the Z adduct, which had previously precluded a definitive assignment of the isomers. In addition, the structures explain why only one of the isomers reacts further with acetylene esters to produce azulenes with a rare substitution pattern. 相似文献
20.
S. Shanmuga Sundara Raj Hoong‐Kun Fun Xu‐Hui Zhu Yan Xu Xiao‐Feng Chen Xiao‐Zeng You 《Acta Crystallographica. Section C, Structural Chemistry》2000,56(1):e6-e7
The Schiff base ligand in the title complex, [Pt(C9H8BrN2S2)2], is deprotonated from its tautomeric thiol form and coordinated to PtIIvia the mercapto S and β–N atoms. The configuration about PtII is a perfect square‐planar, with two equivalent Pt—N [2.023 (3) Å] and Pt—S [2.293 (1) Å] bonds. The phenyl ring is twisted against the coordination moiety Pt1/N1/N1′/S2′/S2 by 31.8 (2)°, due to the steric hindrance induced by ortho‐substituted bulky Br atom. 相似文献