The title compound, [Cu6I6(C2H6N2S)6], was obtained from the reaction of copper(I) iodide with N-methylthiourea (Metu) in equimolar amounts in acetonitile. The complex consists of two six-membered trinuclear Cu3S3I3 cores that combine through triply bridging Metu, forming a hexanuclear core which has -3 symmetry. The CuII atom is coordinated by three S atoms of Metu and one iodide ion in a distorted tetrahedral geometry. The crystal structure is stabilized by N—H⋯I hydrogen bonds and cuprophilic interactions [Cu⋯Cu = 3.0264 (9) Å].
In the crystal structure of the title organic salt, C3H10NO+·IO4
−·C12H24O6, the protonated 2-methoxyethanaminium (CH3OC2H4—NH3
+) cation forms a 1:1 supramolecular rotator–stator complex with the 18-crown-6 molecule via N—H⋯O hydrogen bonds. The (CH3OC2H4—NH3
+) group is attached from the convex side of the bowl-shaped crown, in contrast to similar ammonium cations that nest in the curvature of the bowl. The cations are associated via N—H⋯O interactions, while the cations and anions are linked by weak C—H⋯O hydrogen bonds, forming cation–crown–anion chains parallel to .
The asymmetric unit of the title complex, [Co(DMF)6](ClO4)2 (DMF = N,N-dimethylformamide, C3H7NO), consists of two half complex cations with the Co2+ metal ions located on centers of inversion and two perchlorate anions. In the crystal packing, each Co2+ ion is coordinated by six molecules of DMF in a slightly distorted octahedral geometry. The crystal structure is mainly stabilized by coordinative, ionic and C—H⋯O hydrogen-bonding interactions.
The biodegradation of lignin, one of the most abundant carbon compounds on Earth, has important biotechnological applications in the derivation of useful products from lignocellulosic wastes. The purple photosynthetic bacterium Rhodopseudomonas palustris is able to grow photoheterotrophically under anaerobic conditions on a range of phenylpropeneoid lignin monomers, including coumarate, ferulate, caffeate, and cinnamate. RPA1789 (CouP) is the periplasmic binding-protein component of an ABC system (CouPSTU; RPA1789, RPA1791–1793), which has previously been implicated in the active transport of this class of aromatic substrate. Here, we show using both intrinsic tryptophan fluorescence and isothermal titration calorimetry that CouP binds a range of phenylpropeneoid ligands with Kd values in the nanomolar range. The crystal structure of CouP with ferulate as the bound ligand shows H-bond interactions between the 4-OH group of the aromatic ring with His309 and Gln305. H-bonds are also made between the carboxyl group on the ferulate side chain and Arg197, Ser222, and Thr102. An additional transport system (TarPQM; RPA1782–1784), a member of the tripartite ATP-independent periplasmic (TRAP) transporter family, is encoded at the same locus as rpa1789 and several other genes involved in coumarate metabolism. We show that the periplasmic binding-protein of this system (TarP; RPA1782) also binds coumarate, ferulate, caffeate, and cinnamate with nanomolar Kd values. Thus, we conclude that R. palustris uses two redundant but energetically distinct primary and secondary transporters that both employ high-affinity periplasmic binding-proteins to maximise the uptake of lignin-derived aromatic substrates from the environment. Our data provide a detailed thermodynamic and structural basis for understanding the interaction of lignin-derived aromatic substrates with proteins and will be of use in the further exploitation of the flexible metabolism of R. palustris for anaerobic aromatic biotransformations.
The title complex salt, [Ni(C3H8N2S)6](NO3)2, consists of an [Ni(Dmtu)6]2+ (Dmtu is N,N′-dimethylthiourea) dication and two nitrate counter-anions. The NiII atom (site symmetry ) is coordinated by the S atoms of six Dmtu ligands within a slightly distorted octahedral environment. The crystal structure is characterized by weak intramolecular N—H⋯S interactions and by intermolecular N—H⋯O hydrogen bonds involving the nitrate anion (site symmetry 3.). These intermolecular interactions lead to the formation of two-dimensional networks lying parallel to the ab plane. The networks are linked via non-classical intermolecular C—H⋯O hydrogen bonds, forming a three-dimensional arrangement.
A preliminary X-ray study of the title molecular salt, [Ni(CH4N2S)6](NO3)2, has been reported twice previously, by Maďar [Acta Cryst. (1961), 14, 894] and Rodriguez, Cubero, Vega, Morente & Vazquez [Acta Cryst. (1961), 14, 1101], using film methods. We confirm the previous studies, but to modern standards of precision and with all H atoms located. The central Ni atom (site symmetry ) of the dication is octahedrally coordinated by six S-bound thiourea molecules. The crystal structure is stabilized by intra- and intermolecular N—H⋯S and N—H⋯O hydrogen bonds.
In the cation of the title compound, [Ni(C3H4N2)6](C7H3Br2O2)2·2C3H7NO, the NiII ion lies on an inversion center and is coordinated in a slightly distorted octahedral environment by six N atoms from six imidazole ligands. In the crystal structure, cations, anions and solvent molecules are linked by intermolecular N—H⋯O hydrogen bonds into one-dimensional chains along . In addition, the crystal structure is stabilized by weak C—H⋯O and C—H⋯N hydrogen bonds.
In the title compound, CH3NH3
−·C12H24O6, the methylammonium cation makes three N—H⋯O hydrogen bonds to the 18-crown-6 molecule. The –NH3
+ and –CH3 groups of the cation adopt a staggered conformation. The F atoms of the tetrafluoridoborate anion are disordered over two sets of sites in a 0.519 (11):0.481 (11) ratio. Weak C—H⋯F interactions occur in the crystal, which possibly correlate with the anion disorder.
In the crystal structure of the title compound, [Mn(C3H4N2)6][Mn(C3H4N2)3(H2O)3](C12H6O4)2, there are uncoordinated naphthalenedicarboxylate dianions and two kinds of MnII complex cations, both assuming a distorted octahedral geometry. One MnII cation is located on an inversion center and is coordinated by six imidazole molecules, while the other MnII cation is located on a twofold rotation axis and is coordinated by three water molecules and three imidazole units. The naphthalenedicarboxylate dianions are linked to both MnII complex cations via O—H⋯O and N—H⋯O hydrogen bonding, but no π–π stacking is observed between aromatic rings in the crystal structure.
The asymmetric unit of the title compound, [Fe(C3H4N2)6]SO4·2C3H4N2, contains two complex cations, two sulfate anions and four imidazole molecules. In both cations, the FeII atom is coordinated by six monodentate imidazole ligands and exhibits a slightly distorted octahedral coordination geometry. The Fe—N distances [2.184 (4)–2.218 (4) Å] point to a high-spin state of the Fe2+ ions. N—H⋯O hydrogen bonds between the ionic components generate a three-dimensional framework containing corrugated channels along , which are filled by N—H⋯N hydrogen-bonded imidazole chains.
In the crystal structure of the title compound, [Co(C3H4N2)6](PF6)3·6H2O, the CoIII atom lies on a special position with site-symmetry and the P atom is located on a special position with site symmetry . The CoIII atom has an almost ideal octahedral coordination formed by the N atoms of six imidazole ligands. The water molecules form hydrogen-bonded helical chains propagating in  by O—H⋯O interactions with a distance of 2.913 (2) Å. They simultaneously interact as hydrogen-bond acceptors and donors with the cations and anions, respectively, resulting in the formation of a three-dimensional assembly. Weak C—H⋯F interactions further stabilize the crystal structure.
The asymmetric unit of the title compound, [Co(C4H6N2)6]Br2·2H2O, contains one-half of the centrosymmetric cation, one Br atom and one water molecule. The CoII atom, lying on an inversion center, has a distorted octahedral geometry, defined by six N atoms from six 1-methylimidazole ligands. In the crystal structure, intra- and intermolecular O—H⋯Br hydrogen bonds link pairs of uncoordinated water molecules and bromide anions.
The crystal structure of the title compound, [Ni(C3H4N2)6][Ni(C3H4N2)3(H2O)3](C12H6O4)2, contains uncoordinated naphthalenedicarboxylate dianions and two kinds of NiII complex cations, both assuming distorted octahedral geometries. One NiII ion is located on an inversion center and is coordinated by six imidazole molecules, while the other NiII ion is located on a twofold rotation axis and is coordinated by three water molecules and three imidazole molecules in a mer-NiN3O3 arrangement. The naphthalenedicarboxylate dianion links both NiII complex cations via O—H⋯O and N—H⋯O hydrogen bonding, but no π–π stacking is observed between aromatic rings in the crystal structure. One imidazole ligand is equally disordered over two sites about a twofold rotation axis; one N atom and one water O atom have site symmetry 2.
The reaction of dimethylamine, 18-crown-6, and perchloric acid in methanol yields the title compound, C2H8N+·ClO4
−·C12H24O6·H2O. The dimethylammonium cation and the water molecule interact with the 18-crown-6 unit: N—H⋯O hydrogen bonds are formed between the ammonium NH2
+ group and four O atoms of the crown ether, while the water molecule on the other side of 18-crown-6 ring forms O—H⋯O hydrogen bonds with two other O atoms of the crown ether. All conventional donors and acceptors in the cations are thus engaged in hydrogen bonding. The ClO4
− anion is disordered over two sites, and occupancies for the disordered O atoms were fixed at 0.5. In the crystal, the cations and anions are arranged in alternating layers.
3,6,9,16,19,22-Hexaazatricyclo-[220.127.116.11, 14]triaconta-1(27),11 (30),-12,14(29),24(28),25-hexaene hexakis(p-toluenesulfonate) dihydrate
In the title compound, C24H44N66+·6C7H7O3S−·2H2O, the macrocycle crystallizes in its hexaprotonated form, accompanied by six p-toluenesulfonate ions and two water molecules, and lies on an inversion center. The three independent p-toluenesulfonate anions and their inversion equivalents at (1 − x, 1 − y, 1 − z) are linked to the macrocyclic cation through N–H⋯O hydrogen bonds. Of these, two p-toluenesulfonate ions are located on opposite sides of the macrocyclic plane and are linked to bridgehead N atoms via N–H⋯O hydrogen bonds. The remaining four p-toluenesulfonate ions bridge two adjacent macrocyclic cationic units through N–H⋯O hydrogen bonding involving other N atoms, forming a chain along the a axis. The water molecules, which could not be located and may be disordered, do not interact with the macrocycle; however, they form hydrogen bonds with anions.
single-crystal X-ray study; T = 90 K; mean σ(C–C) = 0.008 Å; H-atom completeness 96%; R factor = 0.072; wR factor = 0.156; data-to-parameter ratio = 16.2
In the title hydrated salt, C36H66N8O6+·6ClO4
−·1.5H2O, the asymmetric unit consists of a hexaprotonated [H6
L]6+ cation, five perchlorate anions in general positions, two on twofold rotation axes (one of which is disordered), and two water molecules of crystallization in general positions, one of them disordered around a twofold crystallographic axis. In the [H6
L]6+ cation, two strong intramolecular N—H⋯N hydrogen bonds occur, involving the N atoms of the oxadiazole ring as acceptors and the closest NH+ groups of each dipropylenetriamine unit. In the crystal, the [H6
L]6+ cations form channels along the a-axis direction, in which the perchlorate counter-ions and the water molecules are lodged. The crystal packing features a network of N—H⋯O and O—H⋯O hydrogen bonds involving the NH+ groups of the [H6
L]6+ cation, the perchlorate anions and the water molecules.
In the title compound, C7H10N+·ClO4
−·C12H24O6, the 4-methylanilinium cation interacts with an 18-crown-6 molecule forming a rotator–stator-like structure through bifurcated N—H⋯(O,O) hydrogen bonds between the ammonium group of the cation and the O atoms of the crown ether molecule. All three components of the structure possess mirror symmetry. The benzene ring is inclined to the mean plane of the crown ether molecule by 86.84 (8)°.
3,6,9,16,19,22-Hexaazatricyclo[18.104.22.168,14]triaconta-1(27),11 (30),12,14(29),24(28),25-hexaene hexakis(p-toluenesulfonate) dihydrate
In the title compound, C24H44N6
6+·6C7H7O3S−·2H2O, the macrocycle crystallizes in its hexaprotonated form, accompanied by six p-toluenesulfonate ions and two water molecules, and lies on an inversion center. The three independent p-toluenesulfonate anions and their inversion equivalents at (1 − x, 1 − y, 1 − z) are linked to the macrocyclic cation through N—H⋯O hydrogen bonds. Of these, two p-toluenesulfonate ions are located on opposite sides of the macrocyclic plane and are linked to bridgehead N atoms via N—H⋯O hydrogen bonds. The remaining four p-toluenesulfonate ions bridge two adjacent macrocyclic cationic units through N—H⋯O hydrogen bonding involving other N atoms, forming a chain along the a axis. The water molecules, which could not be located and may be disordered, do not interact with the macrocycle; however, they form hydrogen bonds with anions.
In the title compound, C7H10N+·BF4
−·C12H24O6, the protonated 4-methylanilinium cation interacts with 18-crown-6 forming a rotator–stator structure, (C6H4CH3NH3
+)(18-crown-6), through three bifurcated N—H⋯(O,O) hydrogen bonds between the ammonium groups of the cations (–NH3) and the O atoms of the crown ether molecule. The BF4
− anions, the methyl group and the protonated –NH3 groups of the 4-methylanilinium lie on a dual axis of rotation. The 18-crown-6 unit is perpendicular to the dual axis of rotation and the mirror plane which contains the dual axis of rotation. The benzene ring of 4-methylanilinium is perpendicular to the mirror plane and parallel to the dual axis.
In the title compound, C6H7IN+·ClO4
−·C12H24O6, the protonated 4-iodoanilinium cation interacts with the 18-crown-6 through three N—H⋯O hydrogen bonds, forming a rotator–stator-like structure. The cation, anion and 18-crown-6 molecule all have crystallographically imposed mirror symmetry.
The reaction of dimethylamine hydrochloride, 18-crown-6 and ferric chloride in ethanol yields the title compound, (C2H8N)[FeCl4]·C12H24O6, which exhibits an unusual supramolecular structure. The protonated dimethylamine contains one NH2
+ group, resulting in a 1:1 supramolecular rotator–stator structure (CH3—NH2
+—CH3)(18-crown-6), through N—H⋯O hydrogen-bonding interactions between the ammonium group of the cation and the O atoms of the crown ether. In the crystal, all three components lie on a common crystallographic mirror plane normal to .
The reaction of 4-fluoroaniline hydrochloride, 18-crown-6 and ferric chloride in methanolic solution yields the title compound, (C6H7FN)[FeCl4]·C12H24O6, which has an unusual supramolecular structure. N—H⋯O hydrogen-bonding interactions between the NH3
+ substituents of the 4-fluoroanilinium cations and the O atoms of the crown ether molecules result in a rotator–stator-like structure.
The reaction of 4-bromo-3-methylanilinium perchlorate and 18-crown-6 in methanol solution yielded the title compound, C7H9BrN+·ClO4
−·C12H24O6. The protonated 4-bromo-3-methylamine unit contains one –NH3
+ substituent, resulting in a 1:1 supramolecular rotator–stator structure, (C7H9Br—NH3
+)(18-crown-6), through three bifurcated N—H⋯(O,O) hydrogen bonds between the ammonium group of the cation and the O atoms of the crown ether molecule.
In the title compound, [Mn(C10H10N2)6](ClO4)2, the MnII ion, located on an inversion center, is coordinated by six N atoms from three pairs of symmetry-related 1-benzyl-1H-imidazole ligands in a distorted octahedral geometry. In the crystal, weak intermolecular C—H⋯O hydrogen bonds link the complex cations and perchlorate anions.
In the title compound, C6H5Cl3N+·ClO4
−·C12H24O6, the perchlorate anion is disordered over two orientations in a 0.666 (17):0.334 (17) ratio. The ammonium group of the organic cation inserts into the crown ether ring and forms three bifurcated N—H⋯(O,O) hydrogen bonds to generate a supramolecular complex. The macrocycle has approximate D
3d local symmetry.