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1.
Abstract Crystallization by slow evaporation of methanol solution of 5-(4-nitrophenyl)-3,4,4a5,6,10b-hexahydro-2H-pyrano[3,2-c] quinoline, yields two polymorphs. Rectangle plate-like crystals have a triclinic (P ) structure, with one molecule in the asymmetric unit, a = 8.2299(5) ?, b = 9.7774(6) ?, c = 11.0047(7) ?, α = 65.718(1)°, β = 75.699(1)° and γ = 71.617(1)°, while, long needle-like crystals exhibit a monoclinic (C2/c) crystal structure in which two independent molecules comprise the asymmetric unit, a = 32.285(3) ?, b = 9.4045(7) ?, c = 22.804(2) ? and β = 114.965(1)°. The crystal structures reveal the molecule in both the polymorphs as an endo-Imino-Diels-Alder cycloadduct isomer. The stereochemistry of the pyran ring in both the polymorphs is exo to the quinoline ring formed in the cycloaddition step. The molecules are linked by N–H···O hydrogen bonds into centrosymmetric dimers forming R2 2(18) rings in the triclinic form, while they are arranged to form a helical chain in the monoclinic form. Index abstract Crystallization by slow evaporation of methanol solution of 5-(4-nitrophenyl)-3,4,4a5,6,10b-hexahydro-2H-pyrano[3,2-c] quinoline, yields two polymorphs. The crystal structures reveal the molecule in both the polymorphs as an endo-Imino-Diels-Alder cycloadduct isomer. The stereochemistry of the pyran ring in both the polymorphs is exo to the quinoline ring formed in the cycloaddition step. The molecules are linked by N–H···O hydrogen bonds into centrosymmetric dimers forming R2 2(18) rings in the triclinic form, while they are arranged to form a helical chain in the monoclinic form. In the present study, we have determined the crystal structures of two polymorphs of pyranoquinoline, I and II.  相似文献   

2.
The reaction of bis(hydroxymethyl)phenylphosphane withtert-butyldichlorophosphane leads to the formation ofcis-2-tert-butyl-5-phenyl-1,3,2,5-dioxadiphosphorinane (1). Thecis configuration was definitively proven by the X-ray diffraction study of the 2, 5-dithioxo derivative (2), which was obtained from (1) by a stereoselective reaction. The diselenoxo compound (3) was also prepared. These three new compounds were subjected to a complete NMR study (1H,13C,31P, and77Se).  相似文献   

3.
The title compound crystallizes in the monoclinic space groupP21/a witha=13.092(2) Å,b=15.853(2) Å,c=15.406(3) Å,=103.00(1)°,V=3116(1) Å3, andD calc=1.237 g cm–3 forZ=4. The structure was solved by direct methods, and refined to a finalR value of 0.057. The phosphetane ligands adopt a nonlinear trans relationship. The four-membered rings are non-planar and have different flap angles of 6.1 and 20.3°. Virtual coupling is evident in the13C NMR spectrum of the title compound. Comparison of the13C NMR spectral data of this molecule with the parent phosphine ligand, the ligand oxide, and the mono-phosphine iron complex is provided.  相似文献   

4.

Abstract  

A secnidazole derivative, 1-(2-chloropropyl)-2-methyl-5-nitro-1H-imidazole (1), was synthesized and its single crystals were successfully grown in the mixture of ethanol/chloroform (3:1) by slow evaporation at room temperature. Its structure was confirmed by 1H NMR, 13C NMR, mass spectra, elemental analyses and X-ray single crystal diffraction. Crystal structure analysis revealed that 1 crystallized in the triclinic, space group P [`1] \overline{1} with the following unit cell parameters: a = 6.5339(7) Ǻ, b = 7.5487(8) Ǻ, c = 9.7238(10) Ǻ, α = 92.894°(2), β = 96.165(2)°, γ = 102.710°(2), V = 463.78(8) ?3, Z = 2. Furthermore, this compound exhibited better anti-urease activity than secnidazole and acetyl-hydroxy acid when evaluated for antimicrobial activity against Helicobacter pylori.  相似文献   

5.

Abstract  

The binuclear zinc complex bis(2-bromobenzoato-O)-bis(μ 2 -2-bromobenzoato-O,O′)-bis(phenazone-O)-dizinc(II) (I) and the mononuclear dihydrate bis(2-bromobenzoato-O)-bis(thiourea-S)-zinc(II) (II) have been synthesized and characterized by means of elemental analysis and spectroscopic methods (IR, 1H and 13C NMR, EDS). The solid state structures of both compounds were determined by single-crystal X-ray diffractometry. Compound [Zn(2-BrC6H4COO)2(phen)]2 (phen—phenazone) (I) crystallized as a dimeric compound with a triclinic lattice (space group P − 1), where both zinc atoms, interconnected by two carboxylate groups, possess a distorted tetrahedral coordination environment. The crystallographic data of complex I: a = 9.9410(3) ?, b = 10.7309(3) ?, c = 12.9237(4) ?, α = 93.6004(17)°, β = 92.5898(11)°, γ = 116.2192(16)°, V = 1230.26(6) ?3, Z = 1. Complex [Zn(2-BrC6H4COO)2(tu)2]·2H2O (tu—thiourea) (II) crystallized with an orthorhombic lattice (space group Aba2) as a monomeric compound, where the coordination environment of the central zinc atom is a distorted tetrahedron. The crystallographic data of complex II are: a = 9.8595(3) ?, b = 19.7052(5) ?, c = 12.5908(3) ?, V = 2446.18(11) ?3, Z = 4. The modes of the carboxylate binding were assigned from the IR spectra using the magnitude of the separation between the carboxylate stretches (Δ), which correlated well with the crystal structures. The computed theoretical IR spectrum agreed well with the experimental data.  相似文献   

6.

Abstract  

The title compound (3), C17H14BrN3O4S, is a Schiff base compound of 5-bromosalicylaldehyde (1) and sulfamethoxazole (2). The structure of (3) was determined by spectral (IR, 1H and 13C NMR), elemental analyses and X-ray diffraction data. Compound (3) crystallizes in the monoclinic space group C2/c, with a = 31.936(3), b = 6.2571(5), c = 16.903(1) ?, β = 94.867(8), V = 3365.5(5) ?3, Z = 8. In the molecule of compound (3), the molecule is bent at the S atom with a C–SO2–NH–C torsion angle of −86.3(3)°. Pairs of molecules, related by inversion centres, form intermolecular N–H···N hydrogen bonds to produce a dimer. An intramolecular phenolic O–H···N hydrogen bond is also formed. Intermolecular hydrogen bonding and π–π stacking hold the molecules together. The average distance between stacked benzene ring planes is 3.625(2) ?.  相似文献   

7.
A new benzimidazole based N-heterocyclic carbene (NHC) salt (1) was synthesized by the reaction of benzimidazole precursor with alkyl halide. The structure of 1 was determined by elemental analysis, FT-IR, 1H NMR and 13C NMR spectroscopy tecniques and X-ray crystallography. The compound crystallized in the triclinic space group P-1 with two molecules in the unit cell. The optimization of 1 was firstly performed at B3LYP/6-311G++(d,p) level, then the theoretical spectral studies performed and compared with the experimental values. Besides the frontier molecular orbital energies and chemical reactivity analysis of 1, together with the electrostatic potential and molecular electrostatic potential analyses were performed at the same level of theory.  相似文献   

8.
The leaf tissue ofAspidosperma cruenta was studied for alkaloid content. Two alkaloids were isolated and shown by a combination of MS, X-ray, and high field NMR analysis to be obscurinervine and obscurinervidine. X-ray analysis of obscurinervine provided the first quantitative structural information on this compound. Obscurinervine (C25H30N2O5) crystallized in the monoclinic space groupP21 with unit cell parametersa=12.863(3)Å,b=9.646(2)Å,c=18.484(3)Å,=105.14(5)°,V=2213.8(8)Å3,D c =1.316 Mg/m3, andZ=4. The structure was solved by direct methods and refined toR=0.054 for 3468 observed reflections. The 2D INADEQUATE NMR experiment provided the first13C chemical shift assignments for obscurinervine. Nineteen of the 2313C-13C connections present were detected. Corresponding13C assignments for obscurinervidine were made by comparison to the spectrum of obscurinervine. The average natural concentrations of the alkaloids were determined to be 0.780% (obscurinervine) and 0.737% (obscurinervidine) by HPLC analysis. Obscurinervine was tested for antiviral and cytotoxic effects. Noin vitro activity was observed.  相似文献   

9.
[Zn(SO2)2][AsF6]2 (1) has been prepared from zinc metal and AsF5 in liquid sulfur dioxide, and crystallized from sulfur dioxide giving crystals of [Zn(SO2)4(AsF6)2] (1a). The compound 1 forms the homoleptic complexes [Zn(NCR)6](AsF6)2 (R: CH3 (2a), C6H5 (3a), C6F5 (3b)) with the corresponding nitriles. In these complexes, the metal center is octahedrally surrounded by six ligands (average Zn–N 2.13 ?). Reaction of 1 with the weaker ligand F3CCN results in dicoordination at the metal center complemented by a two-dimensional polymeric network (2b) containing bridging AsF6 anions. [Zn(SO2)4(AsF6)2] (1a): monoclinic, P21/c, a=8.5176(8) ?, b=13.5787(14) ?, c=14.7661(15) ?, β=99.296(2)°; [Zn(NCCH3)6][AsF6]2 (2a): rhombohedral, R-3, a=11.2225(8) ?, b=11.2225(8) ?, c=16.9393(14) ?; [Zn (NCCF3)2][μ-FAsF5)2( (2b): monoclinic, P21/c, a=11.226(3) ?, b=6.6147(19) ?, c=10.460(3) ?, β=104.028(5)°; [Zn(NCC6H5)6][AsF6]2 (3a): monoclinic, P21/n, a=13.7968(10) ?, b=19.8861(15) ?, c=16.1692(12) ?, β=91.563(2)°; [Zn(NCC6F5)6][AsF6]2·2SO2 (3b): monoclinic, P21/n, a=10.8448(9) ?, b=154456(13) ?, c=17.5206(15) ?, β=104.158(1)°.  相似文献   

10.

Abstract  

Two polymorphs of trilanthanum iridium septaoxide, La3IrO7, were prepared as single crystals using a molten cesium hydroxide flux and were structurally characterized using single-crystal X-ray diffraction. Polymorph A crystallizes in the orthorhombic space group Cmcm with unit cell dimensions of a = 11.2103(3) ?, b = 7.4982(2) ?, and c = 7.6110(2) ?. Polymorph B crystallizes into the monoclinic space group P21/n with the unit cell dimensions of a = 8.8512(5) ?, b = 5.7167(3) ?, c = 24.4454(13) ?, and β = 95.542(2)°. The crystal structure of polymorph A is isostructural to the family of compounds with formula Ln3MO7 (M = Nb5+, Mo5+, Ru5+, Ta5+, Re5+, Os5+, and Ir5+) while the crystal structure of polymorph B has no known corollaries.  相似文献   

11.
Two chalcone compounds, namely (E)-1-phenyl-3-[(2,4,6-trimethylphenyl)]prop-2-en-1-one (1) and (E)-1-phenyl-3-[(4-trifluoromethylphenyl)]prop-2-en-1-one (2), have been synthesized and structurally characterized by elemental analysis, 1H NMR spectrum, and single-crystal X-ray diffraction analysis. The chalcone molecules in (1) and (2) have the common skeleton of 1,3-diaryl-2-propen-1-one and adopt an (E)-configuration about the C = C double bonds. In addition, X-ray analysis reveals that the π···π stacking interactions are well observed in the crystal structure of (1) and (2).  相似文献   

12.

Abstract  

4-Ureidophthalimide or ureido isoindolin-1-one based ligands were shown by NMR spectroscopy and theoretical studies to bind the CG base pairs in the major groove. To examine this hydrogen-bonded complex, we cocrystallized 5-fluorocytosine, 9-methylguanine and 1-(2-methyl-3-oxoisoindolin-5-yl)urea. Two polymorphs of the latter compound were obtained during the cocrystallization attempts. Both crystallized in monoclinic space groups: form Ia in P21/c with cell parameters of a = 11.382(2), b = 6.042(1), c = 14.102(2) ? and β = 96.51(1)°, and form Ib in P21/n with cell parameters of a = 7.092(1), b = 11.643(2), c = 11.580(2) ? and β = 93.48(1)°. An identical molecular conformation of the two polymorphs is observed. Both polymorphs have an R 22(8) N–H···O interaction linking the urea fragments of two molecules to a centrosymmetric dimer. Nevertheless, the crystal packing for both forms is completely different. In Ia, two dimers are connected by two R 21(6) N–H···O bonds simultaneously to a shifted ribbon motif, whereas in Ib the two R 21(6) interactions link two molecules from two different dimers.  相似文献   

13.
The title compounds 3,3,6,6-tetramethyl-9-(2,4-dichlorophenyl)-3,4,6,7,9,10-hexahydro-2H,5H-acridine-1,8-dione 1 (C23H25Cl2NO2, Mr = 418.34) and 3,3,6,6-tetramethyl-9,10-di(4-methoxy-phenyl)-3,4,6,7,9,10-hexahydro-2H,5H-acridine-1,8-dione 2 (C31H35NO4, Mr = 485.60) were synthesized and crystallized. The crystals of compound 1 are monoclinic, space group P21/c, a = 9.826(3), b = 19.866(5), c = 11.471(3) ?, β = 111.929(4)°, Z = 4, V = 2077(1) ?3; The compound 2 crystallizes in space group P21/c, with cell parameters a = 12.089(2), b = 11.447(2), c = 19.742(3) ?, β = 101.00(1)°, V = 2681.8(8) ?3 and D calc = 1.203 g/cm3 for Z = 4. X-ray analysis reveals that atoms C(1), C(6), C(7), C(8), C(13) and N(1) form a 1,4-dihydropyridine ring in compound 1, which adopts half-chair conformation. In compound 2 the atoms C(1), C(6), C(7), C(8), C(13) and N form a 1,4-dihydropyridine ring which adopts boat conformation. In addition, the two outer six-membered rings display half-chair conformations in the crystal structures 1 and 2.  相似文献   

14.
Abstract  Two new peptide compounds, 2(s)-(5-fluorouracil-1-aceto)amino-2-isopropyl acetate hemihydrate (1:1/2H 2 O) and 2(s)-(5-fluorouracil-1-aceto)amino-2-isopropyl acetic acid (2), have been synthesized and characterized by elemental analysis, IR, 1H- and 13C NMR spectroscopy. Two new compounds were structurally characterized by single-crystal X-ray diffraction. The thermal stabilities of compounds 1:1/2H 2 O and 2 were studied by DSC-TGA techniques. The result of the biological test showed that the compounds 1:1/2H 2 O and 2 have certain antitumor activities. Index Abstract  Two new peptide compounds, 2(s)-(5-fluorouracil-1-aceto)amino-2-isopropyl acetate hemihydrate (1:1/2H2O) and 2(s)-(5-fluorouracil-1-aceto)amino-2-isopropyl acetic acid (2), have been synthesized and characterized by elemental analysis, IR, 1H-, and 13C NMR spectroscopy. Two new compounds were structurally characterized by single-crystal X-ray diffraction. The thermal stabilities of compounds 1:1/2H2O and 2 were studied by DSC-TGA techniques. The result of the biological test showed that the compounds 1:1/2H2O and 2 have certain antitumor activities.   相似文献   

15.
Abstract

Solid state NMR measurements are carried out for polymorphs and inclusion complexes of 4,5-bis(4-methoxyphenyl)-2-(3-nitrophenyl)-1H-imidazole. Observed 13C and 15N chemical shifts are characteristic of each polymorph A, B, C and D. In addition, 15N chemical shift was a good index for understanding hydrogen bond. VT measurements revealed that B transforms to C between 93 and 113°C. From PSTMAS and 1H solid echo measurements for AcOET inclusion complex, host molecules have almost same structure as B and guest molecules have the highest mobility of all inclusion complexes.  相似文献   

16.
The crystal structures of isoxazole, 3-[[dihydro-2-[(Z)-2-oxohyrazono]-1H-imidazol-1-(3H)-yl]methyl-5-phenyl-,N-oxide] (C13H13N5O3) (I), isoxazole,3-[[dihydro-2-[(Z)-2-oxohyrazono]-1H-imidazol-1-(3H)-yl]-methyl-5-(4-methylphenyl)-,N-oxide] (C14H15N5O3) (II) and isoxazole, 3-[[dihydro-2-[(Z)-2-oxohyrazono]-1H-imidazol-1-(3H)-yl]-methyl-5-(2-methoxyphenyl)-,N-oxide] (C14H15N5O4) (III) have been determined by X-ray diffraction studies. The compound I, crystallized in triclinic space group with unit cell dimensions a = 7.2405(7) ?, b = 7.9936(8) ?, c = 11.6573(11) ?, α = 97.801(2)°, β = 90.884(2)°, γ = 96.250(2)° and Z = 2. Compound II crystallized in orthorhombic space group Pna21 with unit cell dimensions a = 10.1778(10) ?, b = 28.228(3) ?, c = 5.1206(5) ?, and Z = 4. Compound III crystallized in monoclinic space group P21/n with unit cell dimensions a = 7.8439(9) ?, b = 7.8544(9) ?, c = 23.534(3) ?, β = 99.464(2)° and Z = 4. For all three compounds, the five-membered imidazolidine ring adopts an envelope conformation. The crystal structures are stabilized by both the intramolecular N–H···O and intermolecular N–H···N hydrogen bonding.  相似文献   

17.
2D NMR,1H and13C as well as single crystal X-ray studies were performed in order to establish the correct configuration of all assymetrical centers in the zaluzanines A and B. This work enabled us to correct the previously proposed absolute configuration at the C-5 and C-6 centers, obtained by chemical correlations. Crystals of zaluzanin B (1c) are orthorhombic witha=6.8176(6),b=12.870(2), andc=18.507(5) Å, space groupP212121 and the crystals of the carbodibromo derivative of zaluzanin A diacetate (4) are also orthorhombic witha=14.6123(5),b=15.1218(4), andc=19.9384(4) Å, space groupP21212.  相似文献   

18.
A benzo-phenanthro-fused planar cyclooctatetraene derivative, namely, 5,6,15,16-tetradehydrobenzo[a]phenanthro[9, 10-e]cyclooctene (5) was synthesized in two steps from the known benzo[a]phenanthro[9, 10-e]cyclooctene (6). Compound5 crystallizes in space groupPbam witha=9.828(2),b=19.466(4),c=15.901(3) Å, and Z=8. X-Ray analysis (MoK radiation,R=0.060 for 1233 observed data) has shown that both independent molecules have the same planarC 2v configuration with averaged bond lengths of 1.381(7) and 1.208(7) Å for the phenanthrene C6a–C14b bond and the acetylenic CC bond, respectively.1H and13C NMR spectral results of 5 and 5,6,15,16-tetrabromo-5,6,15,16-tetrahydrobenzo[a]phenanthro[9, 10-e]cyclooctene (7) are also presented.  相似文献   

19.
Abstract The reaction of the potentially tetradentate ligand 1,9-bis(3,5-dimethyl-1-pyrazolyl)-3,7-dithianonane (bddn) with [PtCl2(CH3CN)2] yields a mixture of complexes, where the ligand acts as bidentate SS, or tetradentate 2NS or NSSN. This mixture of complexes SS, 2NS, and NSSN was crystallized with dichloromethane/n-pentane (1:1) and crystals of [Pt(bddn)]Cl2 (isomer NSSN) were obtained. The complex has been characterized by elemental analyses, mass spectrometry, conductivity, IR, 1H, 13C{1H}, 1H{195Pt}, 195Pt{1H}NMR, HSQC and NOESY spectroscopies, and X-ray diffraction. Compound [PtCl2(bddn)] · 3.5H2O crystallizes in the monoclinic space group C2/c with unit cell dimensions a = 15.430(7) ?, b = 17.405(4) ?, c = 18.887(7) ?, β = 91.24(2)°, V = 5071(3) ?3, Z = 4, R 1 = 0.0354, wR2 = 0.1034. This compound consist of discrete cations [Pt(bddn)]2+, Cl anions and water molecules of crystallization. The platinum(II) is tetracoordinated by two azine nitrogen atoms and two sulfur atoms of the thioether-pyrazole ligand, in a distorted square planar geometry. Graphical Abstract Synthesis, Structural Characterization and Spectroscopic Properties of [Pt(bddn)]Cl 2 · 3.5H 2 O (bddn = 1,9-bis(3,5-dimethyl-1-pyrazolyl)-3,7-dithianonane) Antonio de Leon, Josefina Pons*, Jordi García-Antón, Xavier Solans, Mercè Font-Bardia, Josep Ros* Reaction of the ligand 1,9-bis(3,5-dimethyl-1-pyrazolyl)-3,7-dithianonane (bddn) with [PtCl2(CH3CN)2], yields a mixture of complexes. The mixture was crystallized with dichloromethane/pentane (1:1) and crystals of [Pt(bddn)]Cl2 · 3.5 H2O was obtained. Electronic supplementary material The online version of this article contains supplementary material, which is available to authorized users.  相似文献   

20.
Single crystals of Ca(HO3PC6H5)2 (1) and Sr(HO3PC6H5)2 (2) have been obtained via the crystallization of their respective amorphous powders. The amorphous compounds were synthesized by traditional solution routes and were subsequently crystallized at 160°C in a Teflon-lined autoclave containing 1–3 mL distilled water. The resultant single crystals were physically isolated and their structures determined by single crystal X-ray diffraction. The two compounds are isostructural and crystallize in space group C2/c with lattice parameters of a = 31.267(3) ?, b = 5.6185(6) ?, c = 7.7202(8) ?, β = 101.924(2)°; and a = 31.514(4) ?, b = 5.8098(8) ?, c = 7.8218(10) ?, β = 102.063(3)° for the calcium and strontium phenylphosphonate, respectively.  相似文献   

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