Form and function of molecular cups and capsules
Welcome to this CrystEngComm themed issue entitled “Form and Function of Molecular Cups and Capsules”.
Molecular cavity nanoarchitectonics for biomedical application and mechanical cavity manipulation
Based on designed constructions of cavity networks and arrays, macroscopic mechanical motions can lead to cavity manipulations for drug delivery and molecular capture. From biomedical applications to mechanical cavity manipulation, the potential and possibilities of cavity nanoarchitectonics are demonstrated in this highlight.
Metal exchange study of pyrogallolarene based dimers
The synthesis, the single-crystal X-ray structure, and a metal-exchange study of a zinc-seamed C-hexylpyrogallolarene/PgC6Zn dimer are reported.
Host–guest complexes of cucurbituril with the trypanocide drug diminazene and its degradation product 4-aminobenzamidine
The cocrystallization between diminazene and cucurbituril succeeds only after thorough purification of the macrocycle from the acid. Otherwise, the drug molecule undergoes acid-catalyzed hydrolysis with formation of 4-aminobenzamidine.
Solid-state “Russian doll”-like capsules based on a triptycene-derived macrotricyclic host with paraquat derivative and polycyclic aromatic hydrocarbons
“Russian doll”-like complexes based on a triptycene-derived macrotricyclic host with paraquat derivative and polycyclic aromatic hydrocarbons in the solid state were described.
Single-crystal-to-single-crystal transformation of the desolvation of a cyclotriveratrylene–acetonitrile inclusion complex via a gating mechanism with subsequent polymorphism
A cyclotriveratrelyne–acetonitrile inclusion complex is shown to undergo a single-crystal-to-single-crystal transformation upon desolvation to an intermediate phase and it is furthermore demonstrated that the preparation conditions may introduce polymorphism of the apohost.
Ethylene-bridged asymmetric cavitands as building blocks for supramolecular polymers and capsules
A supramolecular polymer as well as a dimeric capsule, both constructed from a combination of a tetra-carboxylic acid functionalized cavitand and a suitable N-heterocyclic ‘linker’, have been crystallographically characterized.
Solid-state assembly of a resorcinarene in twin molecular capsules
In the solid state, a larger resorcinarene self-assembles in twin capsules able to host solvent molecules.
Interaction of a symmetrical α,α′,δ,δ′-tetramethyl-cucurbituril with Ln3+: potential applications for isolation of lanthanides
Interaction of a symmetrical α,α′,δ,δ′-tetramethyl-cucurbituril (TMeQ) with a series of lanthanide cations (Ln3+) was investigated in neutral water and acidic solution.
Influence of the cavity dimension on encapsulation of halides within the capsular assembly and side-cleft recognition of a sulfate–water cluster assisted by polyammonium tripodal receptors
Anion induced capsular and non-capsular assembly of polyammonium tripodal receptors into supramolecular network and formation of side-cleft recognition of a sulfate–water cluster are reported.
Synthesis and recognition properties of calixarene semitubes as ditopic hosts for N-alkylpyridinium ion pairs
Three novel calixarene semitubes having two alkyl bridging spacers of different lengths were synthesized and used as homoditopic hosts for small neutral acidic molecules and N-alkylpyridinium salts.
[CrIII8MII6]n+ (MII = Cu, Co) face-centred, metallosupramolecular cubes
Heterometallic cubes, assembled in a modular fashion from a [CrL3] metalloligand and simple MII salts, display interesting encapsulation and magnetic behaviours.
Encapsulation of biogenic polyamines by carboxylcalixarenes: when solid-state design beats recognition in solution
The regioselective host-to-guest proton transfer readily triggers the formation of overall-neutral supramolecular capsules.
Cationic M2L4 cages for perchlorate removal from aqueous solutions and preferential perchlorate incorporation in hydrophilic solutions
Four new cationic cage type compounds have been synthesized and characterized. Their compounds successfully removed perchlorate ions from aqueous solutions. The solvent dependent anion inclusion of the cationic cage is described.
Coordination of alkaline-earth metal cations to a symmetrical octamethyl-substituted cucurbituril in the presence of polychlorido cadmium(II) anions
Selected alkaline earth ions interact with a symmetric octamethyl-cucurbituril in the presence of polychlorido cadmium(II) anions to yield new porous coordination polymers that reversibly adsorb common volatile liquid vapours.
Unexpected narcissistic self-sorting at molecular and supramolecular levels in racemic chiral calixsalens
Non-covalent interactions drive enantioselective self-recognition in racemic calixsalens.
Synthesis, structures and cytotoxicity studies of p-sulfonatocalixarene lanthanide complexes
A series of lanthanide (Tb, Gd and Eu) based p-sulfonatocalixarene have been synthesized, and screened for their anti-proliferation activity; all complexes exhibited low CC50 values.
Syntheses, structures, luminescence and magnetic properties of three high-nuclearity neodymium compounds based on mixed sulfonylcalixarene-phosphonate ligands
The solvothermal reactions of p-tert-butylsulfonylcalixarene (H4BSC4A), phosphonic acid and neodymium chloride have resulted in three novel high-nuclearity neodymium coordination compounds.
Shaping of calixarenes via double bridging of the upper rim
Direct meta-dimercuration can be used for subsequent bridging of a calixarene skeleton to form an unprecedented, rigid and highly distorted cavity.
Diphosphonate cavitands as molecular cups for L-lactic acid
Two isomeric diphosphonate cavitands (ABii and ACii) were probed for the molecular recognition of L-lactic acid in solution via NMR spectroscopy and in the solid state via crystal structure determination. The interactions involved in the recognition event are a combination of hydrogen bonding and CH–π interactions.
Conformational changes in Cmethyl-resorcinarene pyridine N-oxide inclusion complexes in the solid state
4-Substituted pyridine N-oxides due to cavity misfit form a C2v boat conformer and give 1-D tubular chains, while 2- and 3-methylpyridine N-oxides give in-cavity complexes with a C4v crown conformation.
Anticancer activity of large metalla-assemblies built from half-sandwich complexes
A series of octanuclear p-cymene ruthenium and pentamethylcyclopentadienyl rhodium and iridium metalla-assemblies has been prepared from tetrapyridyl porphyrin panels. All assemblies possess IC50 values around 0.1 μM, and induce apoptosis in cancer cells.
Inverted molecular cups: 1-D and 2-D Ag(I) coordination polymers from resorcinarene bis-thiacrowns
Exo-cavity binding into resorcinarene based inverted molecular cups creates 1-D and 2-D silver coordination polymers with argentophilic interactions.
pH-dependent formation of different coordination cages based on Co4-TC4A secondary building units and bridging ligands
Two kinds of calixarene-based metal–organic coordination cages, a tetrahedral one and a truncated octahedral one, were obtained with the same precursors at different pH values.
Gadolinium(III)-mediated multi-component confinement of imidazolium cations in p-sulfonated calixarene
Multi-component materials having supermolecules made up of mono- or bis-imidazolium cations shrouded by two p-sulfonated calixarenes essentially form molecular capsules as part of the extended structure, with their formation mediated by Gd(III), which is incorporated only in complex I.
About this collection
The issue will focus on the design, assembly, crystalline structure and properties of supramolecular compounds made from building blocks such as calixarenes, cucurbiturils, cyclodextrins, cryptands and other encapsulating species.