Enantiomers of a selective gelatinase inhibitor: (R)- and (S)-2-[(4-phen­oxy­phenyl)­sulfonyl­methyl]thiirane

The R and S enantio­mers of 2-[(4-phen­oxy­phenyl)­sulfonyl­meth­yl]thiirane are discussed and compared with the previously reported racemate. The compound is a selective gelatinase inhibitor.

Dendocarbin A: a sesquiterpene lactone from Drimys winteri

Natural dendocarbin A is a sesquiterpene lactone isolated from Drimys winteri. X-ray crystal structure analysis 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.

(2E)-3-(6-Meth­oxy­naphthalen-2-yl)-1-(pyridin-3-yl)prop-2-en-1-one and its cyclo­condensation product with guanidine, (4RS)-2-amino-4-(6-meth­oxy­naphthalen-2-yl)-6-(pyri­din-3-yl)-3,4-di­hydro­pyrimidine monohydrate: two types of hydrogen-bonded sheet

(2E)-3-(6-Meth­oxy­naphthalen-2-yl)-1-(pyridin-3-yl)prop-2-en-1-one forms sheets built from C—H⋯O and C—H⋯π hydrogen bonds, and the product of its cyclo­condensation with guanidine, (4RS)-2-amino-4-(6-meth­oxy­naphthalen-2-yl)-6-(pyridin-3-yl)-3,4-di­hydro­pyrimidine monohydrate, forms sheets built from N—H⋯O, O—H⋯N and N—H⋯N hydrogen bonds.

Poly[(μ-penta­fluoro­benzoato-κ²O:O′)(penta­fluoro­benzoato-κO)(μ-pyrazine-κ²N:N′)copper(II)]: a coordination polymer linked into a three-dimensional network by inter­molecular C—H⋯F—C inter­actions

The title compound has a five-coordinated Cu^II centre, giving a two-dimensional layer structure formed by Cu—O and Cu—N coordination bonds. The layers are stacked to generate a three-dimensional supra­molecular architecture via inter­molecular C—H⋯F—C inter­actions.

Ionothermal synthesis and crystal structure of a new organic–inorganic hybrid compound: catena-poly[bis­(1-ethyl-3-methyl­imidazolium) [hepta-μ-bromido-penta­cuprate(I)]]

The title organic–inorganic hybrid compound crystallizes in the ortho­rhom­bic space group Pnma. The structure is characterized by polymeric inorganic anionic {[Cu₅Br₇]²⁻}_n chains resulting from the edge-sharing of distorted CuBr₄ tetra­hedra. The anions are surrounded by 1-ethyl-3-methyl­imidazolium cations. C—H⋯Br inter­actions connect the organic cations and inorganic anions.

A three-dimensional Cd^II coordination framework: poly[di-μ₂-aqua-{μ₂-1,4-bis­[(1H-1,2,4-triazol-1-yl)methyl]benzene-κ²N⁴:N^4′}di-μ₃-terephthalato-κ³O:O′:O′′-dicadmium(II)]

A cadmium(II) complex, prepared by reaction of Cd(NO₃)₂·6H₂O with terephthalic acid and 1,4-bis(1,2,4-triazol-1-ylmethyl)benzene in H₂O, possesses a three-dimensional framework with 3,8-connected three-dimensional binodal {4.5²}₂{4².5¹⁰.6¹².7.8³} topology. The compound exhibits a strong fluorescence emission in the solid state at room temperature.

A three-dimensional cyanide-bridged heterometallic coordination polymer: poly[[diaceto­nitrile­diaqua­[μ₂-3,6-bis­(pyridin-2-yl)-1,2,4,5-tetra­zine-κ⁴N¹,N⁶:N³,N⁴]tetra-μ-cyanido-tetracyanidodi­manganese(II)­molybdate(IV)] dihydrate]

A metal coordination polymer has been synthesized by the reaction of Mn(ClO₄)₂·6H₂O with 3,6-bis­(pyridin-2-yl)-1,2,4,5-tetra­zine (bptz) and (Bu₃N)₃[Mo(CN)₈] at room temperature. X-ray diffraction analysis reveals that the compound is a new three-dimensional coordination polymer with a PtS-type network. Magnetic investigation shows anti­ferromagnetic coupling between adjacent Mn²⁺ cations.

A one-dimensional Zn^II coordination polymer: poly[di­chlorido­(μ₂-1,4-phenyl­ene­diacetato-κ²O:O′)bis­{μ₂-1,3-bis­[(1H-1,2,4-triazol-1-yl)methyl]benzene-κ²N³:N^3′}di­zinc(II)]

A Zn^II coordination polymer has been prepared by reaction of ZnCl₂·4H₂O with 1,4-phenyl­ene­di­acetic acid and 1,3-bis­[(1H-1,2,4-triazol-1-yl)meth­yl]benzene in H₂O. Single-crystal X-ray diffraction analysis reveals that the compound possesses a novel one-dimensional rotaxane-like structure.

Coordination preferences of the alkali cations sodium and caesium in the mixed-cationic Zintl ammoniate Cs_3.2Na_0.8Ge₉·5.3NH₃

The involvement of two different alkali cations in the nona­germanide ammoniate Cs_3.2Na_0.8Ge₉·5.3NH₃ provides insights into the coordination behaviour of ammonia towards Na and Cs cations within one compound and represents the first mixed-cationic solvate structure of nona­germanide tetra­anions.

Correlation of the solid-state reactivities of racemic 2,4(6)-di-O-benzoyl-myo-inositol 1,3,5-orthoformate and its 4,4′-bi­pyridine cocrystal with their crystal structures

Racemic 2,4(6)-di-O-benzoyl-myo-inositol 1,3,5-orthoformate shows a very efficient inter­molecular benzoyl-group migration reaction in its crystals due to the helical assembly of mol­ecules, which places the reactive electrophile (C=O) and nucleophile (–OH) in proximity with a preorganized El⋯Nu geometry favourable for the acyl transfer reaction. However, the presence of 4,4′-bi­pyridine mol­ecules in its cocrystal perturbs the helical assembly of the dibenzoate mol­ecules and thus restricts its solid-state reactivity.

The achiral tetra­peptide Z-Aib-Aib-Aib-Gly-OtBu

The achiral tetra­peptide Z-Aib-Aib-Aib-Gly-OtBu has two different conformations which together constitute the asymmetric unit. Both mol­ecules form incipient 3₁₀-helices. They differ in the relative orientation of the N-terminal protecting group and at the C-terminus. There are two 4→1 intra­molecular hydrogen bonds.

The anti­oxidant methyl 3-(3,5-di-tert-butyl-4-hy­droxy­phen­yl)propionate

The structure of the anti­oxidant methyl 3-(3,5-di-tert-butyl-4-hy­droxy­phen­yl)propionate indicates significant strain between the ortho tert-butyl substituents and the phenolic OH group. In spite of the steric crowding of the OH group, it participates in inter­molecular hydrogen bonding with the ester carbonyl O atom.

A new three-dimensional anionic cadmium(II) dicyanamide network

In a new cadmium dicyanamide complex, poly[tetra­methyl­phospho­nium [μ-chlorido-di-μ-dicyanamido-cadmium(II)]], each Cd^II atom is octa­hedrally coordinated by four terminal N atoms from four anionic dicyanamide ligands and by two chloride ligands. The dicyanamide ligands play two different roles in the building up of the structure. The anionic framework exhibits a solvent-accessible void of 673.8 ų, which is 47.44% of the total unit-cell volume. The cavities are occupied by pairs of tetra­methyl­phospho­nium cations.

In situ single-crystal to single-crystal (SCSC) transformation of the one-dimensional polymer catena-poly[[di­aqua(sulfato)copper(II)]-μ₂-glycine] into the two-dimensional polymer poly[μ₂-glycine-μ₄-sulfato-copper(II)]

On heating a crystal of the one-dimensional coordination polymer catena-poly[[diaqua(sulfato)copper(II)]-μ₂-glycine] to 435 K in an oven, its aspect changed from blue to a very pale blue. Crystal structure analysis indicated that it had undergone a single-crystal to single-crystal (SCSC) solid-state transformation, losing two water mol­ecules and forming a two-dimensional coordination polymer, viz. poly[μ₂-glycine-μ₄-sulfato-copper(II)].

2-Ethyl-1-[5-(4-methyl­phen­yl)pyrazol-3-yl]-3-(thio­phene-2-carbon­yl)iso­thio­urea: mol­ecular ribbons containing three types of hydrogen-bonded ring

Mol­ecules of 2-ethyl-1-[5-(4-methyl­phen­yl)pyrazol-3-yl]-3-(thio­phene-2-carbon­yl)iso­thio­urea, formed by reaction of S,S-diethyl 2-thenoylimidodi­thio­carbonate with 5-amino-3-(4-methyl­phen­yl)-1H-pyrazole, form hydrogen-bonded ribbons in which centrosymmetric (4) and (6) rings alternate.

One- and two-dimensional Cd^II coordination polymers incorporating organophosphinate ligands

Linear and two-dimensional coordination polymers incorporating di­phenyl­phosphinate ligands with cadmium(II) both exhibit a single type of phosphinate bridging mode. This study shows that additional neutral organic mol­ecules, such as 4,4′-bi­pyridine, can be used to synthesize higher-dimensional structures beyond that of chains. Such findings prompt future studies aimed at isolating porous materials with potentially useful properties in materials applications.

Hobartine: a tetra­cyclic indole alkaloid extracted from Aristotelia chilensis (maqui)

In the crystal structure of the natural compound hobartine, a tetra­cyclic alkaloid isolated from Aristotelia chilensis, the supra­molecular structure in strongly related to the twofold screw axis, around which isolated chains build up, inter­nally linked by an N—H⋯N hydrogen bond which is the only significant inter­molecular inter­action present in the structure.

A novel two-dimensional Cd^II coordination polymer: poly[aqua­[μ₄-2-(4-carboxylato­benzoyl)benzoato]cadmium(II)]

A Cd^II coordination polymer has been prepared by reaction of Cd(NO₃)₂·6H₂O with 2-(4-carboxybenzoyl)benzoic acid in H₂O at 493 K. Single-crystal X-ray diffraction analysis reveals that the compound possesses a novel two-dimensional framework with a 4,4-connected binodal net topology of point symbol {4³.6².8}. Moreover, the compound exhibits a strong fluorescent emission and typical ferroelectric behaviour in the solid state at room temperature.

An azide-bridged copper(II) complex: poly[piperazine-1,4-dium [tetra-μ₃-azido-κ¹²N¹:N¹:N¹-hexa-μ₂-azido-κ¹²N¹:N¹-di-μ₂-azido-κ⁴N¹:N³-penta­copper(II)] tetra­hydrate]

A new Cu^II–azide complex has been synthesized by the reaction of piperazine, Cu(OAc)₂·2H₂O (OAc is acetate) and NaN₃. In the structure, μ₂-1,1- and μ₃-1,1,1-azide anions bridge five Cu^II cations to form a linear penta­nuclear cluster unit, which is further linked by μ₂-1,1- and μ₂-1,3-azide anions to form a two-dimensional condensed [Cu₅(N₃)₁₂]_n layer.

Hexa­bromo- and hexa­iodo­disilane: small and simple mol­ecules showing completely different crystal structures

Si₂Br₆ and Si₂I₆ were prepared through de­phenyl­ation of hexa­phenyl­disilane with acetyl bromide or acetyl iodide in the presence of the corresponding aluminium halide. It is inter­esting to note that Si₂Br₆ and Si₂I₆ do not form isomorphous structures. Moreover, an ortho­rhom­bic polymorph of the present structure of Si₂I₆ is already known. Although the title compounds feature such small and simple mol­ecules they show completely different crystal structures.