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1.
The natural compound dendocarbin A, C15H22O3, is a sesquiterpene lactone isolated for the first time from Drimys winteri for var chilensis. The compound crystallizes in the orthorhombic space group P212121 and its X‐ray crystal structure confirmed the S/R character of the chiral centres at C‐5/C‐10 and C‐9/C‐11, respectively. The α‐OH group at C‐11 was found to be involved in intermolecular hydrogen bonding, defining chains along the <100> 21 screw axis.  相似文献   

2.
A cocrystal, C15H22O3·C15H22O3, (I), obtained from Drimys winteri, is composed of two isomeric drimane sesquiterpene lactones, namely valdiviolide, (Ia), and 11‐epivaldiviolide, (Ib), neither of which has been reported in the crystal form. Both diastereoisomers present three chiral centres at sites 5, 10 and 11, with an SSR sequence in (Ia) and an SSS sequence in (Ib). O—H...O hydrogen bonds bind molecules into chains running along [20] and the chains are in turn linked by π–π stacking interactions to define planar weakly interacting arrays parallel to (001).  相似文献   

3.
The terpenoid (?)‐Istanbulin A is a natural product isolated from Senecio filaginoides DC, one of the 270 species of Senecio (Asteraceae) which occurs in Argentina. The structure and absolute configuration of this compound [9a‐hydroxy‐3,4a,5‐trimethyl‐4a,6,7,8a,9,9a‐hexahydro‐4H,5H‐naphtho[2,3‐b]‐furan‐2,8‐dione or (4S,5R,8R,10S)‐1‐oxo‐8β‐hydroxy‐10βH‐eremophil‐7(11)‐en‐12,8β‐olide, C15H20O4] were determined by single‐crystal X‐ray diffraction studies. It proved to be a sesquiterpene lactone showing an eremophilanolide skeleton whose chirality is described as 4S,5R,8R,10S. Structural results were also in agreement with the one‐ and two‐dimensional (1D and 2D) NMR and HR–ESI–MS data, and other complementary spectroscopic information. In addition, (?)‐Istanbulin A is a polymorph of the previously reported form of (?)‐Istanbulin A, form I; thus, the title compound is denoted form II or polymorph II. Structural data and a literature search allowed the chirality of Istanbulin A to be revisited. The antimicrobial and antifungal activities of (?)‐Istanbulin A, form II, were evaluated in order to establish a reference for future comparisons and applications related to specific crystal forms of Istanbulins.  相似文献   

4.
The title compound, catena‐poly[[[diaqua(methanol‐κO)copper(II)]‐μ‐N‐(4‐methylpyrimidin‐2‐yl‐κN1)pyrazin‐2‐amine‐κ2N1:N4] [[aqua(aqua/methanol‐κO)(perchlorato‐κO)copper(II)]‐μ‐N‐(4‐methylpyrimidin‐2‐yl‐κN1)pyrazin‐2‐amine‐κ2N1:N4] tris(perchlorate) methanol monosolvate 1.419‐hydrate], {[Cu(C9H9N5)(CH3OH)(H2O)2][Cu(C9H9N5)(ClO4)(CH3OH)0.581(H2O)1.419](ClO4)3·CH3OH·1.419H2O}n, is a one‐dimensional straight‐chain polymer of N‐(4‐methylpyrimidin‐2‐yl)pyrazin‐2‐amine (L) with Cu(ClO4)2. The complex consists of two crystallographically independent one‐dimensional chains in which the CuII atoms exhibit two different octahedral coordination geometries. The L ligand coordinates to two CuII centres in a tridentate manner, with the pyrazine ring acting as a bridge linking the CuII coordination units and building an infinite one‐dimensional chain. Extensive hydrogen bonding among perchlorate anions, water molecules and L ligands results in three‐dimensional networks.  相似文献   

5.
The zinc(II) atom in the crystal structure of the title coordination polymer, [Zn(p‐BDOA)·2H2O]n (p‐BDOA2? = benzene‐1,4‐dioxyacetate), exists in a distorted trigonal prismatic geometry. Adjacent zinc(II) ions are linked by the p‐BDOA2? ligands to furnish a one‐dimensional (1‐D) zigzag chain. A three‐dimensional (3‐D) network structure is stabilized by extended hydrogen bonds. Copyright © 2004 John Wiley & Sons, Ltd.  相似文献   

6.
The structure of the title compound, catena‐poly[[cadmium(II)‐di‐μ‐chlorido‐μ‐(1,4‐diazoniabicyclo[2.2.2]octane‐1‐carboxylato)] [[aquachloridocadmium(II)]‐di‐μ‐chlorido] dihydrate], {[Cd(C8H15N2O2)Cl2][CdCl3(H2O)]·2H2O}n, contains two kinds of independent one‐dimensional chain, viz. {[Cd(C8H15N2O2)Cl2]+}n and {[CdCl3(H2O)]}n, and uncoordinated water molecules. Each CdII cation in the {[Cd(C8H15N2O2)Cl2]+}n chain is octahedrally coordinated by two pairs of bridging chloride ligands and two O atoms from different bridging carboxylate groups. CdII cations in the {[CdCl3(H2O)]}n chain are also octahedrally surrounded by four bridging chloride ligands, one terminal chloride ligand and one coordinated water molecule. Hydrogen bonds between solvent water molecules and these two independent chains generate a three‐dimensional framework containing two‐dimensional zigzag layers.<!?tpb=18pt>  相似文献   

7.
The natural compound (1S ,4S ,5S ,6R ,7R ,8R ,9R ,10S )‐6‐acetoxy‐4,9,10‐trihydroxy‐2,2,5a,9‐tetramethyloctahydro‐2H‐3,9a‐methanobenzo[b ]oxepin‐5‐yl furan‐3‐carboxylate, C22H30O9, (I), is a β‐agarofuran sesquiterpene isolated from the seeds of Maytenus boaria as part of a study of the secondary metabolites from Chilean flora. The compound presents a central structure formed by a decalin system esterified with acetate at site 1 and furan‐3‐carboxylate at site 9. The chirality of the skeleton can be described as 1S ,4S ,5S ,6R ,7R ,8R ,9R ,10S , which is consistent with that suggested by NMR studies. Unlike previously reported structures of sesquiterpenes containing a pure dihydro‐β‐agarofuran skeleton, (I) exhibits a three‐dimensional hydrogen‐bonded network.  相似文献   

8.
The synthesis of coordination polymers or metal–organic frameworks (MOFs) has attracted considerable interest owing to the interesting structures and potential applications of these compounds. It is still a challenge to predict the exact structures and compositions of the final products. A new one‐dimensional coordination polymer, catena‐poly[[[bis{1‐[(1H‐benzimidazol‐2‐yl)methyl]‐1H‐tetrazole‐κN3}zinc(II)]‐μ‐hexane‐1,6‐dicarboxylato‐κ4O1,O1′:O6,O6′] monohydrate], {[Zn(C6H8O4)(C9H8N6)2]·H2O}n, has been synthesized by the reaction of Zn(Ac)2 (Ac is acetate) with 1‐[(1H‐benzimidazol‐2‐yl)methyl]‐1H‐tetrazole (bimt) and adipic acid (H2adi) at room temperature. In the polymer, each ZnII ion exhibits an irregular octahedral ZnN2O4 coordination geometry and is coordinated by two N atoms from two symmetry‐related bimt ligands and four O atoms from two symmetry‐related dianionic adipate ligands. ZnII ions are connected by adipate ligands into a one‐dimensional chain which runs parallel to the c axis. The bimt ligands coordinate to the ZnII ions in a monodentate mode on both sides of the main chain. In the crystal, the one‐dimensional chains are further connected through N—H…O hydrogen bonds, leading to a three‐dimensional supramolecular architecture. In addition, the title polymer exhibits fluorescence, with emissions at 334 and 350 nm in the solid state at room temperature.  相似文献   

9.
Among the potential applications of coordination polymers, electrical conductivity ranks high in technological interest. We report the synthesis, crystal structure and spectroscopic analysis of an AgI–thiosaccharinate one‐dimensional coordination polymer {systematic name: catena‐poly[[[aquatetrakis(μ3‐1,1‐dioxo‐1,2‐benzisothiazole‐3‐thiolato‐κ3N:S3:S3)tetrasilver(I)]‐μ2‐4,4′‐(propane‐1,3‐diyl)dipyridine‐κ2N:N′] dimethyl sulfoxide hemisolvate]}, {[Ag4(C7H4NO2S2)4(C13H14N2)(H2O)]·0.5C2H6OS}n, with the 4,4′‐(propane‐1,3‐diyl)dipyridine ligand acting as a spacer. A relevant feature of the structure is the presence of an unusually short Ag…Ag distance of 2.8306 (9) Å, well within the range of argentophilic interactions, confirmed experimentally as such by a Raman study on the low‐frequency spectrum, and corroborated theoretically by an Atoms in Molecules (AIM) analysis of the calculated electron density. Electrical conductivity measurements show that this complex can act as a semiconductor with moderate conductivity.  相似文献   

10.
The identification of the antibacterial action of nalidixic acid (nx) was central to the development of the quinolone antibacterial compounds. The ability of the nx naphthyridyl ring to interact with and inhibit some proteins has encouraged the investigation of similar structures in the search for more active compounds with less adverse effects. The possibility of structural modification by attachment of other biologically active moieties to the naphthyridyl ring of nx allowed the development of new active antimicrobial molecules. Hydrazone derivatives of nx can be synthesized easily based on the condensation of the hydrazide derivative of nx with the desired aldehyde or ketone. Only a few complexes with nx hydrazone derivatives have been described but for none were the crystal structures elucidated. The synthesis of a new one‐dimensional CuII coordination polymer, namely catena‐poly[[copper(II)‐di‐μ‐chlorido‐copper(II)‐{μ‐1‐ethyl‐N′‐[(1H‐imidazol‐4‐yl)methylidene]‐7‐methyl‐4‐oxo‐1,4‐dihydro‐1,8‐naphthyridine‐3‐carbohydrazidato}‐[dimethanolcopper(II)]‐{μ‐1‐ethyl‐N′‐[(1H‐imidazol‐3‐yl)methylidene]‐7‐methyl‐4‐oxo‐1,4‐dihydro‐1,8‐naphthyridine‐3‐carbohydrazidato}] dichloride methanol tetrasolvate], {[Cu3(C16H15N6O2)2Cl2(CH3OH)2]Cl2·4CH3OH}n, with the (1H‐imidazol‐4‐yl)methylidene carbohydrazide derivative of nalidixic acid (denoted h4imi), is presented and its structure is compared to the density functional theory (DFT) optimized structure of free h4imi. The title structure presents an octahedral CuII ion on an inversion centre alternating along a polymer chain with a square‐pyramidal CuII ion, with the two CuII centres bridged by two chloride ligands. Hydrogen bonds involving chloride counter‐ions and methanol solvent molecules mediate the three‐dimensional packing of the polymer. Comparison of the geometrical results from the structure analysis with those derived from a DFT study of the free ligand reveal the differences that arise upon coordination.  相似文献   

11.
A one‐dimensional zinc(II) coordination polymer has been constructed from zinc(II), 4,4′‐biphenyldicarboxylate and pyridine in which each zinc(II) atom is coordinated by two pyridine ligands and two monodentate 4,4′‐biphenyldicarboxylate ligands that define a distorted tetrahedral geometry. Copyright © 2003 John Wiley & Sons, Ltd.  相似文献   

12.
A novel manganese(III)–porphyrin complex, namely, catena‐poly[[chloridomanganese(III)]‐μ2‐5,10,15,20‐tetrakis(pyridin‐3‐yl)‐21H,23H‐porphinato(2?)‐κ5N21,N22,N23,N24:N5], [MnCl(C40H24N8)]n, 1 , was prepared by the hydrothermal reaction of manganese chloride with 5,10,15,20‐tetrakis(pyridin‐3‐yl)‐21H,23H‐porphine. The crystal structure was determined by single‐crystal X‐ray diffraction. The porphyrin macrocycle exhibits a saddle‐like distortion geometry. The MnIII atom has a six‐coordination geometry. Each porphyrin unit links to two neighbouring units to yield a one‐dimensional coordination polymer. These chains are further interlinked by hydrogen bonds to form a two‐dimensional network. The complex shows red photoluminescence emission bands in ethanol solution, which can be attributed to ligand‐to‐ligand charge transfer (LLCT) accompanied by partial metal‐to‐ligand charge transfer (MLCT), as revealed by TDDFT calculations.  相似文献   

13.
Pyrazolidine‐3,5‐diones and their derivatives exhibit a wide range of biological activities. Seeking to explore the effect of combining a hydrocarbyl ring substituent, as present in sulfinpyrazone (used to treat gout), with a chlorinated aryl ring, as present in muzolimine (a diuretic), we explored the reaction between 1‐phenylpyrazolidine‐3,5‐dione and 4‐chlorobenzaldehyde under mildly basic conditions in the expectation of producing the simple condensation product 4‐(4‐chlorobenzylidene)‐1‐phenylpyrazolidine‐3,5‐dione. However, the reaction product proved to be meso‐(E,E)‐1,1′‐[1,2‐bis(4‐chlorophenyl)ethane‐1,2‐diyl]bis(phenyldiazene), C26H20Cl2N4, and a tentative mechanism is proposed. Crystallization from ethanol produces two concomitant polymorphs, i.e. a triclinic form, (I), in the space group P, and a monoclinic form, (II), in the space group C2/c. In both polymorphs, the molecules lie across centres of inversion, but in (II), the molecules are subject to whole‐molecule disorder equivalent to configurational disorder with occupancies of 0.6021 (19) and 0.3979 (19). There are no hydrogen bonds in the crystal structure of polymorph (I), but the molecules of polymorph (II) are linked by C—H...π(arene) hydrogen bonds into complex chains, which are further linked into sheets by C—H...N interactions.  相似文献   

14.
4‐Hydroxypyridine‐2,6‐dicarboxylic acid (chelidamic acid, hypydc[H]H2) reacts with MnCl2·2H2O in the presence of piperazine in water to afford the title complex, {[Mn3(C7H2NO5)2(H2O)8]·3H2O}n or {[Mn3(hypydc)2(H2O)8]·3H2O}n. This compound is a one‐dimensional coordination polymer, with the twofold symmetric repeat unit containing three metal centres. Two different coordination geometries are observed for the two independent MnII metal centres, viz. a distorted pentagonal bipyramid and a distorted octahedron. The 4‐oxidopyridine‐2,6‐dicarboxylate anions and two of the water molecules act as bridging ligands. The zigzag‐like geometry of the coordination polymer is stabilized by hydrogen bonds. O—H...O and C—H...O hydrogen bonds and water clusters consolidate the three‐dimensional network structure.  相似文献   

15.
A new cyanide‐bridged FeIII–MnII heterobimetallic coordination polymer (CP), namely catena‐poly[[[N,N′‐(1,2‐phenylene)bis(pyridine‐2‐carboxamidato)‐κ4N,N′,N′′,N′′′]iron(III)]‐μ‐cyanido‐κ2C:N‐[bis(4,4′‐bipyridine‐κN)bis(methanol‐κO)manganese(II)]‐μ‐cyanido‐κ2N:C], {[FeMn(C18H12N4O2)(CN)2(C10H8N2)2(CH3OH)2]ClO4}n, ( 1 ), was prepared by the self‐assembly of the trans‐dicyanidoiron(III)‐containing building block [Fe(bpb)(CN)2]? [bpb2? = N,N′‐(1,2‐phenylene)bis(pyridine‐2‐carboxamidate)], [Mn(ClO4)2]·6H2O and 4,4′‐bipyridine, and was structurally characterized by elemental analysis, IR spectroscopy, single‐crystal X‐ray crystallography and powder X‐ray diffraction (PXRD). Single‐crystal X‐ray diffraction analysis shows that CP 1 possesses a cationic linear chain structure consisting of alternating cyanide‐bridged Fe–Mn units, with free perchlorate as the charge‐balancing anion, which can be further extended into a two‐dimensional supramolecular sheet structure via inter‐chain π–π interactions between the 4,4′‐bipyridine ligands. Within the chain, each MnII ion is six‐coordinated by an N6 unit and is involved in a slightly distorted octahedral coordination geometry. Investigation of the magnetic properties of 1 reveals an antiferromagnetic coupling between the cyanide‐bridged FeIII and MnII ions. A best fit of the magnetic susceptibility based on the one‐dimensional alternating chain model leads to the magnetic coupling constants J1 = ?1.35 and J2 = ?1.05 cm?1, and the antiferromagnetic coupling was further confirmed by spin Hamiltonian‐based density functional theoretical (DFT) calculations.  相似文献   

16.
The title compound, catena‐poly[[[bis(ethylenediamine‐κ2N,N′)platinum(II)]‐ μ‐chlorido‐[bis(ethylenediamine)platinum(IV)]‐μ‐chlorido] tetrakis{4‐[(4‐hydroxyphenyl)diazenyl]benzenesulfonate} dihydrate], {[PtIIPtIVCl2(C2H8N2)4](HOC6H4N=NC6H4SO3)4·2H2O}n, has a linear chain structure composed of square‐planar [Pt(en)2]2+ (en is ethylenediamine) and elongated octahedral trans‐[PtCl2(en)2]2+ cations stacked alternately, bridged by Cl atoms, along the b axis. The Pt atoms are located on an inversion centre, while the Cl atoms are disordered over two sites and form a zigzag ...Cl—PtIV—Cl...PtII... chain, with a PtIV—Cl bond length of 2.3140 (14) Å, an interatomic PtII...Cl distance of 3.5969 (15) Å and a PtIV—Cl...PtII angle of 170.66 (6)°. The structural parameter indicating the mixed‐valence state of the Pt atom, expressed by δ = (PtIV—Cl)/(PtII...Cl), is 0.643.  相似文献   

17.
The asymmetric unit of the title salt, C12H24N+·C2H2BrO2, contains a dicyclohexylammonium cation connected to a bromoacetate anion by means of an N—H...O hydrogen bond. In the crystal, the ion pairs assemble via N—H...O interactions, forming zigzag infinite chains parallel to the c axis with the (...H—N—H...O—C—O...)n motif that is considered to be a prerequisite for ensuring gelation properties of secondary ammonium monocarboxylate salts. The title salt was characterized by FT–IR, X‐ray powder diffraction (XRPD), TG–DTA and 1H NMR spectroscopy in solution. Gelation experiments revealed that dicyclohexylammonium bromoacetate forms molecular gels with dimethylformamide and dimethyl sulfoxide. Scanning electron microscopy (SEM) was used to reveal morphological features of dried gels.  相似文献   

18.
An infinite one‐dimensional cadmium metal–organic chain, namely catena‐poly[aquabis(μ3‐2,2′‐{[1,2‐phenylenebis(methylene)]bis(sulfanediyl)}dibenzoato)dicadmium(II)], [Cd2(C22H16O4S2)2(H2O)]n, was synthesized by solvothermal reaction of Cd(NO3)2·4H2O and 2,2′‐{[1,2‐phenylenebis(methylene)]bis(sulfanediyl)}dibenzoic acid (H2L). The CdII centres have six‐coordinate CdS2O4 and CdSO5 geometries. Due to the flexible –CH2–S– arms, the L2− ligand adopts both syn and anti conformations. Four CdII cations are linked by two syn L2− ligands to form a centrosymmetric planar tetranuclear CdII core, which is further extended through bonding to the anti L2− ligands to form a one‐dimensional metal–organic chain. Adjacent one‐dimensional chains are connected by C—H...π interactions and nonclassical C—H...O hydrogen bonds to form the resultant three‐dimensional supramolecular framework.  相似文献   

19.
The coordination polymer catena‐poly[[(dimethylformamide‐κO)[μ3‐5‐(1,3‐dioxo‐4,5,6,7‐tetraphenylisoindolin‐2‐yl)isophthalato‐κ4O1,O1′:O3:O3′](methanol‐κO)manganese(III)] dimethylformamide monosolvate], {[Mn(C40H23NO6)(CH3OH)(C3H7NO)]·C3H7NO}n, has been synthesized from the reaction of 5‐(1,3‐dioxo‐4,5,6,7‐tetraphenylisoindolin‐2‐yl)isophthalic acid and manganese(II) acetate tetrahydrate in a glass tube at room temperature by solvent diffusion. The MnII centre is hexacoordinated by two O atoms from one chelating carboxylate group, by two O atoms from two monodentate carboxylate groups and by one O atom each from a methanol and a dimethylformamide (DMF) ligand. The single‐crystal structure crystallizes in the triclinic space group P. Moreover, the coordination polymer shows one‐dimensional 2‐connected {0} uninodal chain networks, and free DMF molecules are connected to the chains by O—H...O hydrogen bonds. The thermogravimetric and photoluminescent properties of the compound have also been investigated.  相似文献   

20.
Subtle modifications of N‐donor ligands can result in complexes with very different compositions and architectures. In the complex catena‐poly[[bis{1‐[(1H‐benzotriazol‐1‐yl)methyl]‐1H‐imidazole‐κN 3}copper(II)]‐μ‐benzene‐1,3‐dicarboxylato‐κ3O 1,O 1′:O 3], {[Cu(C8H4O4)(C10H9N5)2(H2O)]·2H2O}n , each CuII ion is six‐coordinated by two N atoms from two crystallographically independent 1‐[(1H‐benzotriazol‐1‐yl)methyl]‐1H‐imidazole (bmi) ligands, by three O atoms from two symmetry‐related benzene‐1,3‐dicarboxylate (bdic2−) ligands and by one water molecule, leading to a distorted CuN2O4 octahedral coordination environment. The CuII ions are connected by bridging bdic2− anions to generate a one‐dimensional chain. The bmi ligands coordinate to the CuII ions in monodentate modes and are pendant on opposite sides of the main chain. In the crystal, the chains are linked by O—H…O and O—H…N hydrogen bonds, as well as by π–π interactions, into a three‐dimensional network. A thermogravimetric analysis was carried out and the fluorescence behaviour of the complex was also investigated.  相似文献   

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