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1.
A salt of vandetanib, namely, 4-({4-[(4-bromo-2-fluorophenyl)amino]-6-methoxyquinazolin-7-yl}methoxy)-1-methylpiperazin-1-ium 2-(butylamino)-4-phenoxy-6-sulfamoylbenzoate acetonitrile monosolvate, C22H25BrFN4O2+·C17H19N2O5S·C2H3N, composed of kinase inhibitor vandetanib and sulfamyl diuretic bumetanide in a 1:1 molar ratio, is reported. There is proton transfer between the piperidine ring of vandetanib and the carboxyl group of bumetanide to form the salt. In the vandetanib cation, the arene and pyrimidine rings are not coplanar, their planes subtending a dihedral angle of 60.47 (14)°. The roles of the intermolecular interactions in the crystal packing were clarified using Hirshfeld surface analysis, and two-dimensional fingerprint plots indicate that the most important contributions to the crystal packing are from H…H (40.5%), O…H/H…C (20.7%), C…H/ H…C (18.8%) and N…C/C…N (9.0%) contacts.  相似文献   

2.
Crown ethers and their supramolecular derivatives are well‐known chelators and scavengers for a variety of cations, most notably heavier alkali and alkaline‐earth ions. Although they are widely used in synthetic chemistry, available crystal structures of uncoordinated and solvent‐free crown ethers regularly suffer from disorder. In this study, we present the X‐ray crystal structure analysis of well‐ordered solvent‐free crystals of dibenzo‐21‐crown‐7 (systematic name: dibenzo[b ,k ]‐1,4,7,10,13,16,19‐heptaoxacycloheneicosa‐2,11‐diene, C22H28O7). Because of the quality of the crystal and diffraction data, we have chosen invarioms, in addition to standard independent spherical atoms, for modelling and briefly discuss the different refinement results. The electrostatic potential, which is directly deducible from the invariom model, and the Hirshfeld surface are analysed and complemented with interaction‐energy computations to characterize intermolecular contacts. The boat‐like molecules stack along the a axis and are arranged as dimers of chains, which assemble as rows to form a three‐dimensional structure. Dispersive C—H…H—C and C—H…π interactions dominate, but nonclassical hydrogen bonds are present and reflect the overall rather weak electrostatic influence. A fingerprint plot of the Hirshfeld surface summarizes and visualizes the intermolecular interactions. The insight gained into the crystal structure of dibenzo‐21‐crown‐7 not only demonstrates the power of invariom refinement, Hirshfeld surface analysis and interaction‐energy computation, but also hints at favourable conditions for crystallizing solvent‐free crown ethers.  相似文献   

3.
The crystal structures of five new transition‐metal complexes synthesized using thiazole‐2‐carboxylic acid (2‐Htza), imidazole‐2‐carboxylic acid (2‐H2ima) or 1,3‐oxazole‐4‐carboxylic acid (4‐Hoxa), namely diaquabis(thiazole‐2‐carboxylato‐κ2N,O)cobalt(II), [Co(C4H2NO2S)2(H2O)2], 1 , diaquabis(thiazole‐2‐carboxylato‐κ2N,O)nickel(II), [Ni(C4H2NO2S)2(H2O)2], 2 , diaquabis(thiazole‐2‐carboxylato‐κ2N,O)cadmium(II), [Cd(C4H2NO2S)2(H2O)2], 3 , diaquabis(1H‐imidazole‐2‐carboxylato‐κ2N3,O)cobalt(II), [Co(C4H2N2O2)2(H2O)2], 4 , and diaquabis(1,3‐oxazole‐4‐carboxylato‐κ2N,O4)cobalt(II), [Co(C4H2NO3)2(H2O)2], 5 , are reported. The influence of the nature of the heteroatom and the position of the carboxyl group in relation to the heteroatom on the self‐assembly process are discussed based upon Hirshfeld surface analysis and used to explain the observed differences in the single‐crystal structures and the supramolecular frameworks and topologies of complexes 1 – 5 .  相似文献   

4.
5.
The crystal structures of the antimicrobial drug tinidazole [ TNZ ; systematic name: 1‐(2‐ethylsulfonylethyl)‐2‐methyl‐5‐nitroimidazole, C8H13N3O4S] and the 1:1 cocrystal of TNZ with the naturally occurring compound vanillic acid ( VA ; systematic name: 4‐hydroxy‐3‐methoxybenzoic acid, C8H8O4), namely, the TNZ – VA cocrystal, were determined by single‐crystal X‐ray analysis at 100 K. The supramolecular structure of the TNZ – VA cocrystal is composed of a carboxylic acid dimer and an O—H…N(heterocycle) synthon in the form of layers made up of O—H…N and O—H…O hydrogen bonds. The layers are joined via C—H…O hydrogen bonds, π–π stacking and C—H…π interactions. The energy framework analysis, together with interaction energy calculations using the DLPNO‐CCSD(T) method, indicates that the TNZ – VA cocrystal inherits strong interactions from the TNZ and VA crystals, which accounts for the enhanced thermal stability and reduced dissolution rate. To the best of our knowledge, this is the first example of a cocrystal containing TNZ .  相似文献   

6.
Two chalcones were synthesized by the aldolic condensation of enolizable aromatic ketones with substituted benzaldehydes under Claisen–Schmidt reaction conditions and then treated with 2,4‐dinitrophenylhydrazine to yield their corresponding hydrazones. The two (E,Z)‐2,4‐dinitrophenylhydrazone structures, namely (Z)‐1‐(2,4‐dinitrophenyl)‐2‐[(E)‐3‐(4‐methylphenyl)‐1‐phenylallylidene]hydrazine, C22H18N4O4, ( H1 ), and (Z)‐1‐[(E)‐3‐(4‐chlorophenyl)‐1‐(naphthalen‐1‐yl)allylidene]‐2‐(2,4‐dinitrophenyl)hydrazine, C25H17ClN4O4, ( H2 ), were isolated by recrystallization and characterized by FT–IR, UV–Vis, single‐crystal and powder X‐ray diffraction methods. The UV–Vis spectra of the hydrazones have been studied in two organic solvents of different polarity. It was found that ( H2 ) has a molar extinction coefficient larger than 40000. Single‐crystal X‐ray diffraction analysis reveals that the molecular zigzag chains of ( H1 ) and ( H2 ) are interconnected through noncovalent contacts. A quantitative analysis of the intermolecular interactions in the crystal structures has been performed using Hirshfeld surface analysis. All the synthesized chalcones and hydrazones were evaluated for their antibacterial and antioxidant activities. Results indicate that the studied compounds show significant activity against Gram negative Escherichia coli strain and the chalcone 3‐(4‐methylphenyl)‐1‐phenylprop‐2‐en‐1‐one, ( C1 ), was the most effective. In addition, only hydrazone ( H1 ) displayed a moderate DPPH (2,2‐diphenyl‐1‐picryl hydrazyl) scavenging efficiency.  相似文献   

7.
Two novel trinuclear cluster-based coordination polymers {[M3(dip)(AcO)6]·(X)}n (1, M = Cu, X = CH3OH; 2, M = Co, X = 2H2O) (dip is 2,6-Di-imidazol-1-yl-pyridine), have been synthesised and structurally determined by single crystal X-ray diffraction, element analysis. Crystallographic unit of 1 consists of three Cu(II), six acetic ions, one dip ligand and one methanol molecule, which formed 1D chain through acetic bridges. The 1D chain further constructed 2-D network through dip ligand bridge which formed 3-D network through π···π interaction. Crystallographic unit of 2 consists of three Co(II), six acetic ions, one dip ligand and two water molecules. The trinuclear unit further formed a dimmer through dip ligand bridge which constructed 1-D through dip ligand bridge. The 1D chain further constructed 2-D network through π···π interaction. IR and UV–vis spectrum properties of 1 and 2 were studied. In addition, Hirshfeld surface analysis was also studied for 1.  相似文献   

8.
There are few examples of single‐crystal structure determinations of gelators, as gel formation requires that the dissolved gelator self‐assemble into a three‐dimensional network structure incorporating solvent via noncovalent interactions rather than self‐assembly followed by crystallization. In the solid‐state structures of the isostructural compounds 4,4′‐bis[5‐(methoxycarbonyl)pentyloxy]biphenyl (BBO6‐Me), C26H34O6, and 4,4′‐bis[5‐(ethoxycarbonyl)pentyloxy]biphenyl (BBO6‐Et), C28H38O6, the molecules sit on a crystallographically imposed center of symmetry, resulting in strictly coplanar phenyl rings. BBO6‐Me behaves as an organogelator in various alcohol solvents, whereas BBO6‐Et does not. The extended structure reveals bundles of molecules that form a columnar superstructure. Framework‐energy calculations reveal much stronger interaction energies within the columns (−52 to −78 kJ mol−1) than between columns (−2 to −16 kJ mol−1). The intracolumnar interactions are dominated by a dispersion component, whereas the intercolumnar interactions have a substantial electrostatic component.  相似文献   

9.
READY (REActive DYnamics) is a program for studying reactive dynamic systems using a global potential energy surface (PES) built from previously existing PESs corresponding to each of the most important elementary reactions present in the system. We present an application to the combustion dynamics of a mixture of hydrogen and oxygen using accurate PESs for all the systems involving up to four oxygen and hydrogen atoms. Results at the temperature of 4000 K and pressure of 2 atm are presented and compared with model based on rate constants. Drawbacks and advantages of this approach are discussed and future directions of research are pointed out. © 2014 Wiley Periodicals, Inc.  相似文献   

10.
Diorganotin (IV) complexes SnR2X2 (R = Me, Ph; X = Cl, NCS) form a series of versatile complexes when react with bidentate substituted pyridyl ligands. The reaction of dimethyltin dichloride with 5,5′‐dimethyl‐2,2′‐bipyridine (5,5′‐Me2bpy) resulted in the formation of [SnMe2Cl2(5,5′‐Me2bpy)] ( 1 ). Moreover, the reaction of SnMe2(NSC)2 with 4,4′‐di‐tert‐butyl‐2,2′‐bipyridine (bu2bpy), 1,10‐phenanthroline (phen) and 4,7‐diphenyl‐1,10‐phenanthroline (bphen) affords the hexa‐coordinated complexes [SnMe2(NCS)2(bu2bpy)] ( 2 ), [SnMe2(NCS)2(phen)] ( 3 ) and [SnMe2(NCS)2(bphen)] ( 4 ), respectively. The resulting complexes have been characterized using elemental analysis, IR, multinuclear NMR (1H, 13C, 119Sn) and DEPT‐135° NMR spectroscopy. On the other hand, the reaction of diphenyltin dichloride with 2,2′‐biquinoline (biq) and 4,7‐phenantroline (4,7‐phen) led to the formation of polymeric complexes of [SnPh2Cl2(4,7‐phen)]n ( 5 ) and [SnPh2Cl2(biq)]n ( 6 ). The NMR spectra, however, reveal the ligand lability in solution and suggest a coordination number of 5 . The X‐ray crystal structures of complexes [SnMe2Cl2(5,5′‐Me2bpy)] ( 1 ), [SnMe2(NCS)2(bu2bpy)] ( 2 ) and [SnMe2(NCS)2(bphen)] ( 4 ) have been determined which reveal that the geometry around the tin atom is distorted octahedral with trans‐[SnMe2] configuration. Interestingly, the crystal structure of (H2biq)2[SnPh2Cl4]?2CHCl3 ( 7 ) was characterized by X‐ray crystallography from a chloroform solution of [SnPh2Cl2(biq)]n ( 6 ) indicating the formation of doubly protonated [H2biq]+ and [Ph2SnCl4]2? which are stabilized by a network of hydrogen bonds with a feature of trans‐[SnPh2]. The 3D Hirshfeld surface analysis and 2D fingerprint maps were used for quantitative mapping out of the intermolecular interactions for 1 , 2 , 4 and 7 which show the presence of π‐π and hydrogen bonding interactions which are associated between donor and acceptor atoms (N, S, Cl) in the solid state.  相似文献   

11.
以二-吡嗪-(2, 3-f: 2′3′-h)-喹喔啉(Dpq)和吡啶-2,5-二羧酸(2,5-H2pda)两种混合配体与不同金属硝酸盐为原料,通过水热反应得到了两个新奇的金属有机骨架[Zn2(Dpq)2(2,5-pda)2(H2O)2]·2H2O(1)和[Cd2(Dpq)2(2,5-pda)2]·2H2O(2),并经元素分析、TG、IR、X-射线单晶衍射分析进行了表征。结构分析表明,2,5-pda采取不同的配位方式桥连金属离子分别形成了二聚物1和2D菱形网络2。在化合物1中,相邻的二聚物通过氢键和π-π堆积作用形成扭曲的a-Po超分子结构。在化合物2中,相邻的配位聚合物层通过氢键拓展成扭曲的a-Po超分子骨架,而π-π堆积起到巩固骨架的作用。化合物1和2的结构差异表明了金属离子和配体在配位聚合物自组装过程中对结构的影响。此外固态标题化合物在室温下表现出蓝色的发光性质。  相似文献   

12.
The existence of intermolecular interactions and the conformational geometry adopted by molecules are related to biological activity. Xanthenedione molecules are promising and emerging antioxidants and acetylcholinesterase inhibitors. To examine the role of different functional groups involved in the intermolecular interactions and conformational geometries adopted in xanthenediones, a series of three substituted xanthenediones have been crystallized [9‐(3‐hydroxyphenyl)‐3,3,6,6‐tetramethyl‐3,4,5,6,7,9‐hexahydro‐1H‐xanthene‐1,8(2H)‐dione, C23H26O4, 9‐(5‐bromo‐2‐methoxyphenyl)‐3,3,6,6‐tetramethyl‐3,4,6,7‐tetrahydro‐2H‐xanthene‐1,8(5H,9H)‐dione, C24H27BrO4, and 3,3,6,6‐tetramethyl‐9‐(pyridin‐2‐yl)‐3,4,6,7‐tetrahydro‐2H‐xanthene‐1,8(5H,9H)‐dione, C22H25NO3] and their intermolecular interactions analyzed via Hirshfeld analysis. The results show that all the derivatives adopt the same structural conformation, where the central ring has a shallow boat conformation and the outer rings have a twisted boat conformation. The intermolecular interactions in the molecules are predominantly O—H…O, C—H…O and π–π interactions. The optimized structures of the derivatives from theoretical B3LYP/6‐311G** calculations show a good correlation with the experimental structures. The lattice energy involved in the intermolecular interactions has been explored using PIXELC.  相似文献   

13.
A series of cadmium (II) complexes with the general formula of CdLX2, where X = Cl, Br, I, SCN and N3 and L is a tetradentate N4-donor Schiff base ligand; were synthesized by a sonochemical process as a simple, cost effective and environmentally friendly method. The organic ligand was obtained by condensation reaction of triethylenetetraamine (trien) and cinnamaldehyde. The characterization of coordination compounds was carried out by FT-IR, 1HNMR, 13CNMR, UV–visible spectroscopies and then conductivity measurements. The crystal structure of the cadmium azide complex was determined by single crystal X-ray diffraction. This complex crystallizes in the monoclinic space group of C2/c. The cadmium ion is hexa-coordinated by four nitrogen atoms from the tetradendate Schiff base ligand and two terminal azide nitrogen atoms. The crystal packing and Hirshfeld surface analysis of the CdL(N3)2 complex indicates the essential role of intermolecular interactions related to azido groups in the formation of supramolecular structure. The thermal behavior of complexes was studied by TG/DTG analysis. Moreover, an antibacterial bioassay of the cadmium complexes has been performed in vitro against two gram-positive (Staphylococcus aureus and Bacillus subtilis) and two gram-negative (Escherichia coli and Pseudomonas aeruginosa) bacterial strains. Furthermore antifungal activities of the compounds against two fungal strains of Aspergilus niger and Candida albicans were also investigated.  相似文献   

14.
A protein energy surface is constructed. Validation is through applications of global energy minimization to surface loops of protein crystal structures. For 9 of 10 predictions, the native backbone conformation is identified correctly. Electrostatic energy is modeled as a pairwise sum of interactions between anisotropic atomic charge densities. Model repulsion energy has a softness similar to that seen in ab initio data. Intrinsic torsional energy is modeled as a sum over pairs of adjacent torsion angles of 2-dimensional Fourier series. Hydrophobic energy is that of a hydration shell model. The remainder of hydration free energy is obtained as the energetic effect of a continuous dielectric medium. Parameters are adjusted to reproduce the following data: a complete set of ab initio energy surfaces, meaning one for each pair of adjacent torsion angles of each blocked amino acid; experimental crystal structures and sublimation energies for nine model compounds; ab initio energies over 1014 conformations of 15 small-molecule dimers; and experimental hydration free energies for 48 model compounds. All ab initio data is at the Hartree–Fock/6–31G* level. © 1998 John Wiley & Sons, Inc. J Comput Chem 19: 548–573, 1998  相似文献   

15.
The ability of the antibacterial agent sulfameter (SMT) to form solvates is investigated. The X‐ray crystal structures of sulfameter solvates have been determined to be conformational polymorphs. Both 1,4‐dioxane and tetrahydrofuran form solvates with sulfameter in a 1:1 molar ratio. 4‐Amino‐N‐(5‐methoxypyrimidin‐2‐yl)benzenesulfonamide (polymorph III), C11H12N4O3S, (1), has two molecules of sulfameter in the asymmetric unit cell. 4‐Amino‐N‐(5‐methoxypyrimidin‐2‐yl)benzenesulfonamide 1,4‐dioxane monosolvate, C11H12N4O3S·C4H8O2, (2), and 4‐amino‐N‐(5‐methoxypyrimidin‐2‐yl)benzenesulfonamide tetrahydrofuran monosolvate, C11H12N4O3S·C4H8O, (3), crystallize in the imide form. Hirshfeld surface analyses and fingerprint analyses were performed to study the nature of the interactions and their quantitative contributions towards the crystal packing. Finally, Hirshfeld surfaces, fingerprint plots and structural overlays were employed for a comparison of the two independent molecules in the asymmetric unit of (1), and also for a comparison of (2) and (3) in the monoclinic crystal system. A three‐dimensional hydrogen‐bonding network exists in all three structures, involving one of the sulfone O atoms and the aniline N atom. All three structures are stabilized by strong intermolecular N—H...N interactions. The tetrahydrofuran solvent molecule also takes part in forming significant intermolecular C—H...O interactions in the crystal structure of (3), contributing to the stability of the crystal packing.  相似文献   

16.
Poly[oxy[[2-(perfluorooctyl)ethyl]thiomethyl]ethylene]s (H2F8TP-Xs, where X is mole% of perfluorooctyl groups in the side chain) with different levels of conversion were synthesized using polymer analogous reactions from poly[oxy(chloromethyl)ethylene] and 2-perfluorooctyl ethane thioacetate. H2F8TP-20, 41, 64, and 85 were obtained by changing the poly[oxy(chloromethyl)ethylene] to 2-perfluorooctyl ethane thioacetate mole ratio in the reaction from 0.35 to 1.50. H2F8TP-85 (85% conversion) was found to have an extremely low surface energy of 6.2 mN/m at room temperature, which was attributed to the highly ordered perfluorinated alkyl groups on the surface as a result of phase separation between the perfluorinated side chain part and the hydrogenated flexible backbone. The films of the polymers were characterized by electron spectroscopy for chemical analysis (ESCA) and near edge X-ray absorption fine structure (NEXAFS).  相似文献   

17.
Three newly designed containing‐PMBP N2O2‐donors complexes, [Co(L1)(CH3OH)2] ( 1 ), [{Zn(L2)(CH3OH)(H2O)}3] ( 2 ) and [Cu4(L2)4]?2CHCl3 ( 3 ), have been synthesized and structurally characterized using elemental analyses, infrared and UV–visible spectroscopies and single‐crystal X‐ray diffraction. X‐ray crystal structure determinations revealed that 1 consists of one Co(II) atom, one completely deprotonated (L1)2? unit and two coordinated methanol molecules. Complex 2 consists of three Zn(II) atoms, three completely deprotonated (L2)2? units, three coordinated methanol molecules and three coordinated water molecules. However, 3 includes four Cu(II) atoms, four completely deprotonated (L2)2? units and two crystallization chloroform molecules. The Co(II) and Zn(II) atoms in the structures of 1 and 2 adopt slightly distorted octahedral geometries. While, Cu(II) atoms in 3 can be best described as adopting slightly distorted square planar geometries. Complex 2 is a novel structure, and the ratio of H2L2 to Zn(II) atom is 3:3. In addition, two‐, three‐ and three‐dimensional supramolecular structures were constructed for 1 , 2 and 3 . Most importantly, Hirshfeld surface analysis of 1 , 2 and 3 was conducted and fluorescence properties were investigated.  相似文献   

18.
19.
20.
A series of related acetylacetonate–carbonyl–rhodium compounds substituted by functionalized phosphines has been prepared in good to excellent yields by the reaction of [Rh(acac)(CO)2] (acac is acetylacetonate) with the corresponding allyl‐, cyanomethyl‐ or cyanoethyl‐substituted phosphines. All compounds were fully characterized by 31P, 1H, 13C NMR and IR spectroscopy. The X‐ray structures of (acetylacetonato‐κ2O,O′)(tert‐butylphosphanedicarbonitrile‐κP)carbonylrhodium(I), [Rh(C5H7O2)(CO)(C8H13N2)] or [Rh(acac)(CO)(tBuP(CH2CN)2}] ( 2b ), (acetylacetonato‐κ2O,O′)carbonyl[3‐(diphenylphosphanyl)propanenitrile‐κP]rhodium(I), [Rh(C5H7O2)(C15H14N)(CO)] or [Rh(acac)(CO){Ph2P(CH2CH2CN)}] ( 2h ), and (acetylacetonato‐κ2O,O′)carbonyl[3‐(di‐tert‐butylphosphanyl)propanenitrile‐κP]rhodium(I), [Rh(C5H7O2)(C11H22N)(CO)] or [Rh(acac)(CO){tBu2P(CH2CH2CN)}] ( 2i ), showed a square‐planar geometry around the Rh atom with a significant trans influence over the acetylacetonate moiety, evidenced by long Rh—O bond lengths as expected for poor π‐acceptor phosphines. The Rh—P distances displayed an inverse linear dependence with the coupling constants JP‐Rh and the IR ν(C[triple‐bond]O) bands, which accounts for the Rh—P electronic bonding feature (poor π‐acceptors) of these complexes. A combined study from density functional theory (DFT) calculations and an evaluation of the intramolecular H…Rh contacts from X‐ray diffraction data allowed a comparison of the conformational preferences of these complexes in the solid state versus the isolated compounds in the gas phase. For 2b , 2h and 2i , an energy‐framework study evidenced that the crystal structures are mainly governed by dispersive energy. In fact, strong pairwise molecular dispersive interactions are responsible for the columnar arrangement observed in these complexes. A Hirshfeld surface analysis employing three‐dimensional molecular surface contours and two‐dimensional fingerprint plots indicated that the structures are stabilized by H…H, C…H, H…O, H…N and H…Rh intermolecular interactions.  相似文献   

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