Felodipine–diazabicyclo[2.2.2]octane–water (1/1/1)

The title compound, C₁₈H₁₉Cl₂NO₄·C₆H₁₂N₂·H₂O, is a cocrystal hydrate containing the active pharmaceutical ingredient felodipine and diazabicyclo[2.2.2]octane (DABCO). The DABCO and water molecules are linked through O—H...N hydrogen bonds into chains around 2₁ screw axes, while the felodipine molecules form N—H...O hydrogen bonds to the water molecules. The felodipine molecules adopt centrosymmetric back‐to‐back arrangements that are similar to those present in all of its four reported polymorphs. The dichlorophenyl rings also form π‐stacking interactions. The inclusion of water molecules in the cocrystal, rather than formation of N—H...N hydrogen bonds between felodipine and DABCO, may be associated with steric hindrance that would arise between DABCO and the methyl groups of felodipine if they were directly involved in hydrogen bonding.     

Threefold interweaving of (4,4) nets built from R(58) rings in the hydrogen‐bonded adduct 1,4‐diaza­bicyclo[2.2.2]octane–5‐hydroxy­isophthalic acid (1/1)

The 1:1 adduct of 1,4‐di­aza­bi­cyclo­[2.2.2]­octane and 5‐hydroxy­isophthalic acid is a salt, [H(C₆H₁₂N₂)]⁺·­[HOC₆H₃(COOH)COO]^? or C₆H₁₃N₂⁺·C₈H₅O₅^?. The ions are linked by three types of hydrogen bond, i.e. N—H?O, O—H?O and O—H?N, into continuous two‐dimensional (4,4) nets built from a single type of R(58) ring. Six independent sheets of this type make up the structure and these are interwoven in sets of three.     

The 2:1 complex of maleic acid and 1,4‐diazabicyclo[2.2.2]octane: hydrogen‐bonded sheets linked by C–H⋯O hydrogen bonds

In the title complex, 1,4‐diazo­niabi­cyclo­[2.2.2]­octane bis­(hy­drogen maleate), C₆H₁₄N₂²⁺·2C₄H₃O₄^?, the C₄H₃O₄^? and C₆H₁₄N₂²⁺ ions, derived from maleic acid and 1,4‐di­aza­bi­cyclo­[2.2.2]­octane, respectively, are disordered across a mirror plane in space group Cmc2₁, and they are linked by two nearly linear N—H?O hydrogen bonds, with N?O distances of 2.662 (3) and 2.614 (4) Å, and N—H?O angles of 173°. The crystal structure consists of sheets with reticulations of 3.3792 (4) Å in stratum and 7.3892 (8) Å in width. The sheets are linked by C—H?O hydrogen bonds.     

Halogen‐bonded adduct of 1,2‐dibromo‐1,1,2,2‐tetrafluoroethane and 1,4‐diazabicyclo[2.2.2]octane

Halogen bonding is an intermolecular interaction capable of being used to direct extended structures. Typical halogen‐bonding systems involve a noncovalent interaction between a Lewis base, such as an amine, as an acceptor and a halogen atom of a halofluorocarbon as a donor. Vapour‐phase diffusion of 1,4‐diazabicyclo[2.2.2]octane (DABCO) with 1,2‐dibromotetrafluoroethane results in crystals of the 1:1 adduct, C₂Br₂F₄·C₆H₁₂N₂, which crystallizes as an infinite one‐dimensional polymeric structure linked by intermolecular N...Br halogen bonds [2.829 (3) Å], which are 0.57 Å shorter than the sum of the van der Waals radii.     

Mononuclear and dinuclear bromide–nitrite cadmium(II) complexes with related 1,4‐diazabicyclo[2.2.2]octane ligands

The title compounds, di‐μ‐bromido‐bis[bromido(1‐carboxymethyl‐4‐aza‐1‐azoniabicyclo[2.2.2]octane‐κN⁴)(nitrito‐κ²O,O′)cadmium(II)] dihydrate, [Cd₂Br₄(C₈H₁₅N₂O₂)₂(NO₂)₂]·2H₂O, (I), and aquabromido(1‐cyanomethyl‐4‐aza‐1‐azoniabicyclo[2.2.2]octane‐κN⁴)bis(nitrito‐κ²O,O′)cadmium(II) monohydrate, [CdBr(C₈H₁₄N₃)(NO₂)₂(H₂O)]·H₂O, (II), are two‐dimensional hydrogen‐bonded metal–organic hybrid complexes. In (I), the complex is situated on a centre of inversion so that each symmetry‐related Cd^II atom is coordinated by two bridging Br atoms, one monodentate Br atom, one chelating nitrite ligand and one organic ligand, yielding a significantly distorted octahedral geometry. The combination of O—H...O and O—H...Br hydrogen bonds produces centrosymmetric R₆⁶(16) ring motifs, resulting in two‐dimensional layers parallel to the ab plane. In contrast, the complex molecule in (II) is mononuclear, with the Cd^II atom seven‐coordinated by two bidentate nitrite groups, one N atom from the organic ligand, one monodentate Br atom and a water O atom in a distorted pentagonal–bipyramidal environment. The combination of O—H...O and O—H...Br hydrogen bonds produces R₅⁴(14) and R₃³(8) rings which lead to two‐dimensional layers parallel to the ac plane.     

N‐(4‐Nitrobenzoyl)‐N′‐phenylhydrazine: a three‐dimensional hydrogen‐bonded framework

In the title compound (systematic name: N‐anilino‐4‐nitrobenzamide), C₁₃H₁₁N₃O₃, the molecules are linked into a complex three‐dimensional framework structure by a combination of two‐centre N—H...O and C—H...O hydrogen bonds and a three‐centre N—H...(O,N) hydrogen bond.     

1,4‐Di­aza­bi­cyclo­[2.2.2]­octane‐1,4‐diium trichromate

The title compound, (C₆H₁₄N₂)[Cr₃O₁₀], consists of a di­aza­bi­cyclo­[2.2.2]­octane‐1,4‐diium cation and a discrete trichromate anion linked by an N—H⋯O hydrogen bond. Three CrO₄ tetrahedra are joined via shared O atoms to form the trichromate anion. Supramolecular rings, which can be described by the graph‐set motif (26), are built via N—H⋯O hydrogen bonds, and C—H⋯O interactions play lesser roles in forming the structure.     

Benzene‐1,4‐diboronic acid–4,4′‐bipyridine–water (1/2/2)

In the presence of water, benzene‐1,4‐diboronic acid (1,4‐bdba) and 4,4′‐bipyridine (4,4′‐bpy) form a cocrystal of composition (1,4‐bdba)(4,4′‐bpy)₂(H₂O)₂, in which the molecular components are organized in two, so far unknown, cyclophane‐type hydrogen‐bonding patterns. The asymmetric unit of the title compound, C₆H₈B₂O₄·2C₁₀H₈N₂·2H₂O, contains two 4,4′‐bpy, two water molecules and two halves of 1,4‐bdba molecules arranged around crystallographic inversion centers. The occurrence of O—H...O and O—H...N hydrogen bonds involving the water molecules and all O atoms of boronic acid gives rise to a two‐dimensional hydrogen‐bonded layer structure that develops parallel to the (01) plane. This supramolecular organization is reinforced by π–π interactions between symmetry‐related 4,4′‐bpy molecules.     

Di­aza­bi­cyclo­[2.2.2]­octane‐1,4‐diium dichromate

The title compound, (C₆H₁₄N₂)[Cr₂O₇], consists of a di­aza­bi­cyclo­[2.2.2]­octane‐1,4‐diium cation and a discrete dichromate anion, which are linked in the crystal by N—H⋯O hydrogen bonds. The cation is ordered and distorted, owing to the confinement and twist of the hydrogen bonds involved. Two CrO₄ tetrahedra are joined through a shared O atom to form the dichromate anion. Chiral supramolecular chains of the title compound are built up via N—H⋯O hydrogen bonds, and C—H⋯O interactions play subordinate roles in forming the structure.     

rac‐(Z)‐2‐(2‐Thienylmethylene)‐1‐azabicyclo[2.2.2]octan‐3‐ol

The asymmetric unit of the racemic form of the title compound, C₁₂H₁₅NOS, contains four crystallographically independent molecules. The olefinic bond connecting the 2‐thienyl and 1‐azabicyclo[2.2.2]octan‐3‐ol moieties has Z geometry. Strong hydrogen bonding occurs in a directed co‐operative O—H...O—H...O—H...O—H R₄⁴(8) pattern that influences the conformation of the molecules. Co‐operative C—H...π interactions between thienyl rings are also present. The average dihedral angle between adjacent thienyl rings is 87.09 (4)°.     

Rietveld refinement of the cocrystal 2,4‐dihydroxybenzoic acid–N′‐(propan‐2‐ylidene)nicotinohydrazide (1/1)

A further example of using a covalent‐bond‐forming reaction to alter supramolecular assembly by modification of hydrogen‐bonding possibilities is presented. This concept was introduced by Lemmerer, Bernstein & Kahlenberg [CrystEngComm (2011), 13 , 55–59]. The title structure, C₉H₁₁N₃O·C₇H₆O₄, which consists of a reacted niazid molecule, viz.N′‐(propan‐2‐ylidene)nicotinohydrazide, and 2,4‐dihydroxybenzoic acid, was solved from powder diffraction data using simulated annealing. The results further demonstrate the relevance and utility of powder diffraction as an analytical tool in the study of cocrystals and their hydrogen‐bond interactions.     

N‐(3‐tert‐Butyl‐1‐phenyl‐1H‐pyrazol‐5‐yl)‐N‐(4‐methoxybenzyl)acetamide: a hydrogen‐bonded chain of centrosymmetric rings

The molecule of the title compound, C₂₃H₂₇N₃O₂, adopts a conformation having no internal symmetry so that the compound exhibits conformational chirality. The molecules are linked by a combination of C—H...O and C—H...π(arene) hydrogen bonds into a chain of rings in which two types of centrosymmetric ring alternate.     

1,4‐Diazabicyclo[2.2.2]octane‐Catalyzed One‐Pot Synthesis of Pyrazolo[1,2‐a][1,2,4]triazole‐1,3‐diones under Ultrasound Acceleration

1,4‐Diazabicyclo[2.2.2]octane has been explored as an efficient catalyst to effect the three‐component condensation reactions between malononitrile, 4‐arylurazoles, and aromatic aldehydes in ethanol under ultrasound irradiation conditions. The reactions proceeded very rapidly under mild conditions to furnish the corresponding pyrazolo[1,2‐a][1,2,4]triazole‐1,3‐dione derivatives in excellent yields.     

Synthesis and Biological Activity of 4‐[(Substituted Phenoxyacetoxy)methyl]‐2,6,7‐trioxa‐1‐phosphabicyclo[2.2.2]octane‐1‐one

A series of novel 4‐[(substituted phenoxyacetoxy)methyl]‐2,6,7‐trioxa‐1‐phosphabicyclo[2.2.2]octane‐1‐one 4a , 4b , 4c , 4d , 4e , 4f , 4g , 4h , 4i , 4j , 4k , 4l , 4m , 4n , 4o were synthesized. Their structures were confirmed by IR, ¹H NMR, mass spectroscopy, and elemental analyses. The results of preliminary bioassays show that some of the title compounds exhibit moderate to good herbicidal and fungicidal activities. For example, the title compounds 4b , 4c , 4f , 4h , 4i , and 4j possess 90–100% inhibition against the growth of roots of both rape and barnyard grass at 10 mg/L. Moreover, the title compounds 4f , 4g , and 4h possess 75–89% inhibition against Botrytis cinerea at the concentration of 50 mg/L.     

A structural hierarchy in the hydrogen‐bonded adduct N,N′‐di­methyl­piperazine–tartaric acid–water (1/2/2): an N‐component N‐dimensional structure (N = 3) with substructures having N = 1 and 2

In the hydrated adduct N,N′‐di­methyl­piperazine‐1,4‐diium bis(3‐carboxy‐2,3‐di­hydroxy­propanoate) dihydrate, [MeNH(CH₂CH₂)₂NHMe]²⁺·2(C₄H₅O₆)^?·2H₂O or C₆H₁₆N₂²⁺·2C₄H₅O₆^?·2H₂O, formed between racemic tartaric acid and N,N′‐di­methyl­piperazine (triclinic P, Z′ = 0.5), the cations lie across centres of inversion. The anions alone form chains, and anions and water mol­ecules together form sheets; the sheets are linked by the cations to form a pillared‐layer framework. The supramolecular architecture thus takes the form of a family of N‐dimensional N‐component structures having N = 1, 2 or 3.     

The Synthesis of 1,4‐Bis[N‐(4/6‐Substituted Benzothiazole‐2‐yl)‐N′‐Glycosylguanidino]Benzenes

The starting material O‐protected glycosyl isothiocyanate ( 1?3 ) was refluxed with 1,4‐diaminobenzene in CHCl₃ under nitrogen atmosphere to give 1,4‐bis(N‐glycosyl)thioureidobenzene ( 4?6 ). Then 1,4‐bis[N‐(4/6‐substituted benzothiazole‐2‐yl)‐N′‐glycosylguanidino]benzenes ( 8a?8e , 9a?9e , 10a?10e ) were obtained in good yield by reaction of compounds ( 4?6 ) with 2‐amino‐4/6‐benzothizoles ( 7a?7e ) and HgCl₂ in the presence of TEA in DMF. The structures of all 18 new compounds were confirmed by IR, ¹H NMR, LC‐MS and elemental analysis. The bioactivity of anti‐HIV‐1 protease (HIV‐1 PR) and against angiotensin converting enzyme (ACE) have been evaluated.     

Coordinative NB bond formation and hydrogen‐bonded molecular ladders in 2,5‐bis[(N→B)‐(2‐aminoethoxy)phenylboryl]thiophene

The molecular structure of the title compound, C₂₀H₂₄B₂­N₂O₂S, is characterized by a twofold rotation axis passing through the S atom and the midpoint of the C—C single bond in the thio­phene ring. A coordinative NB bond is present in the boroxazolidine ring and a single N—H?O hydrogen bond [H?O 1.93 (3) Å, N?O 2.829 (3) Å and N—H?O 172 (2)°] links the mol­ecules into a molecular ladder.     

The hydrogen‐bonded adduct 7,16‐diazonia‐18‐crown‐6–4‐aminobenzenesulfonate–water (1/2/2)

In the title hydrated adduct, 1,4,10,13‐tetraoxa‐7,16‐diazo­nia­cyclo­octa­decane bis(4‐amino­benzene­sulfonate) dihydrate, C₁₂H₂₈N₂O₄²⁺·2C₆H₆NO₃S⁻·2H₂O, formed between 7,16‐di­aza‐18‐crown‐6 and the dihydrate of 4‐amino­benzene­sulfonic acid, the macrocyclic cations lie across centres of inversion in the orthorhombic space group Pbca. The anions alone form zigzag chains, and the cations and anions together form sheets that are linked via water mol­ecules and anions to form a three‐dimensional grid.     

Two methyl 3‐(1H‐pyrazol‐4‐yl)octahydropyrrolo[3,4‐c]pyrrole‐1‐carboxylates form different hydrogen‐bonded sheets

In the molecules of both methyl (1RS,3SR,3aRS,6aSR)‐1‐methyl‐3‐(3‐methyl‐1‐phenyl‐1H‐pyrazol‐4‐yl)‐4,6‐dioxo‐5‐phenyloctahydropyrrolo[3,4‐c]pyrrole‐1‐carboxylate, C₂₅H₂₄N₄O₄, (I), and methyl (1RS,3SR,3aRS,6aSR)‐5‐(4‐chlorophenyl)‐1‐methyl‐3‐(3‐methyl‐1‐phenyl‐1H‐pyrazol‐4‐yl)‐4,6‐dioxooctahydropyrrolo[3,4‐c]pyrrole‐1‐carboxylate, C₂₅H₂₃ClN₄O₄, (II), the two rings of the pyrrolopyrrole fragment are both nonplanar, with conformations close to half‐chair forms. The overall conformations of the molecules of (I) and (II) are very similar, apart from the orientation of the ester function. The molecules of (I) are linked into sheets by a combination of an N—H...π(pyrrole) hydrogen bond and three independent C—H...O hydrogen bonds. The molecules of (II) are also linked into sheets, which are generated by a combination of an N—H...N hydrogen bond and two independent C—H...O hydrogen bonds, weakly augmented by a C—H...π(arene) hydrogen bond.     

A structural hierarchy in the hydrogen‐bonded adduct ethane‐1,2‐di­phospho­nic acid–4,4′‐bipyridyl–water (1/1/2): an N‐component N‐­dimensional structure (N = 3) with substructures having N = 1 and 2

The title compound, 4,4′‐bipyridinium ethane‐1,2‐diyl‐1,2‐di­phospho­nate dihydrate, is a hydrated salt, C₁₀H₁₀N₂²⁺·­C₂H₆O₆P₂^2?·2H₂O, in which the components are linked by extensive hydrogen bonding. The cations and anions lie on inversion centres and with the water mol­ecules each form separate one‐component one‐dimensional chains along [100]: the anions and the water mol­ecules form a two‐component two‐dimensional substructure, (001) sheets, while the cations and anions form a second two‐component two‐dimensional substructure, (011) sheets. All three components combine to form a three‐dimensional framework.