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Supramolecular cages/vesicles in biology display sophisticated structures and functions by utilizing a few types of protein subunit quasi‐equivalently at distinct geometrical locations. However, synthetic supramolecular cages still lack comparable complexity to reach the high levels of functionality found in natural systems. Herein we report the self‐assembly of giant pentagonal supramolecular prisms (molecular weight >50 kDa) with tetratopic pyridinyl subunits serving different geometrical roles within the structures, and their packing into a novel superstructure with unexpected three‐fold rotational symmetry in a single two‐dimensional layer of crystalline state. The formation of these complicated structures is controlled by both the predetermined angles of the ligands and the mismatched structural tensions created from the multi‐layered geometry of the building blocks. Such a self‐assembly strategy is extensively used by viruses to increase the volume and complexity of capsids and would provide a new approach to construct highly sophisticated supramolecular architectures. [ABSTRACT FROM AUTHOR]

Despite the widespread clinical application of chemotherapeutic anticancer drugs, their adverse side effects and inefficient performances remain ongoing issues. A drug delivery system (DDS) designed for a specific cancer may therefore overcome the drawbacks of single chemotherapeutic drugs and provide precise and synergistical cancer treatment by introducing exclusive stimulus responsiveness and combined chemotherapy properties. Herein, we report the design and synthesis of a supramolecular drug delivery assembly 1 constructed by orthogonal self-assembly technique in aqueous media specifically for application in liver cancer therapy. Complex 1 incorporates the β-cyclodextrin host moleculefunctionalized organoplatinum(II) metallacycle 2 with two specific stimulus-responsive motifs to the signaling molecule nitric oxide (NO), in addition to the three-armed polyethylene glycol (PEG) functionalized ferrocene 3 with redox responsiveness. With this molecular design, the particularly low critical aggregation concentration (CAC) of assembly 1 allowed encapsulation of the commercial anticancer drug doxorubicin (DOX). Controlled drug release was also achieved by morphological transfer via a sensitive response to the endogenous redox and NO stimuli, which are specifically related to the microenvironment of liver tumor cells. Upon combination of these properties with the anticancer ability from the platinum acceptor, in vitro studies demonstrated that DOX-loaded 1 is able to codeliver anticancer drugs and exhibit therapeutic effectiveness to liver tumor sites via a synergistic effect, thereby revealing a potential DDS platform for precise liver cancer therapeutics. [ABSTRACT FROM AUTHOR]

Analyses of PQQ (methoxatin), a bis(quinone)tricarboxylic acid and an organic cofactor in several biological redox mechanisms confirm that organic cations such as N-methylphenazonium (phenazine methosulfate), berberine and MPP+ (N-methylphenylpyridinium) sequester PQQ and inhibit its capacity to catalyze glycinate-fueled redox cycling. Bis(iodonium)triflates inhibit PQQ at nanomolar levels. Alkynyl and arly monoiodonium salts inhibit PQQ at micromolar levels.

Alkynyl(phenyl)iodonium triflates interact with NaSO2Ar to give alkynyl sulfones in an easy manner and in substantial quantity. Halogen and alcohol functionalities and alkyl and aryl replacements are added to the medium of the interaction due to the lack of the base and oxidizing factors in the medium. The new method is recommended for the preparation of alkynyl sulfones due to easy accessibility and constancy of alkynyliodonium salts when paired with the gentle environment of the interaction.

A novel approach is described for the construction of multicomponent two-dimensional (2-D) and three-dimensional (3-D) metallosupramolecules. This method is used for preparing a variety of 2-D rectangles and 3-D prisms and multicomponent self-assembly is achieved by supramolecule-to-supramolecule transformations.

A new series of dendritic tris(crown ether) hexagons is constructed via coordination-driven self-assembly. The studies have shown that the association constants of each assembly decrease correspondingly upon the increase of the generation of the dendrons from [G0] to [G3], which is caused by the steric effect of the dendrons on host-guest complexation.

Ion mobility spectrometry-mass spectrometry (IMS-MS) is used to study the rigid rectangular, triangular, and prismatic supramolecular assemblies in the complexes of anthracene, phenanthrene and cyclobutadienecyclopentadienylcobalt based on dipyridyl ligands and square planar platinum coordination. The obtained results confirmed the utility of IMS-MS methods for characterization self-assembled complex structures when X-ray or other spectroscopic structures are not available.

The article presents a new technique, which employs the multicomponent coordination-driven self-assembly process for the synthesis of 3-D mettalosupramolecular tetragonal prisms.

The synthesis and scanning tunneling microscopy (STM) analysis of shape-persistent arylene-ethynylene-butadiynylene macrocycles along with their codeposites with metallacycles are described. The unit-cell data of the macrocycles and their codeposites have shown that the structural information of the macrocycle layer is transformed to the guest molecules.

The ultrafast dynamics of two different platinum-containing metallacycles are examined by using femtosecond fluorescence upconversion and transient absorption. The results have shown that differences in the dimensionality and structure of metallacycles have resulted in different optical properties, which are used in designing nonlinear optical materials and potential new, longer-lived excited state materials for electronic applications.

The synthesis of three endofunctionalized two-dimensional supramolecular metallacycles including two [2 + 2] rhomboids and a [3 + 3] hexagon is reported. The characterization of the self-assembled supramolecular structures containing several nitrobenzyl moieties at their interior surface revealed a significant C-H***O hydrogen bonding between the nitrobenzyl acceptor and the edge molecules of the supramolecular architecture.

The article presents a new methodology, which can be used for the synthesis of the neutral dendritic metallocycles via the oxygen-to-platinum coordination. The shape, size, as well as the structures of the metallocycles ar also explained.

A general strategy is described for preparing stable, multicomponent fused polygon complexes in which coordination-driven self-assembly has allowed for single supramolecular species to be formed from multicomponent self-assembly and the shape of the obtained polygons is controlled by changing the ratio of individual components. The compounds are characterized by multinuclear NMR spectroscopy and electrospray ionization mass spectrometry.

The design and synthesis of two new heterofunctional hexagons containing both redox-active ferrocenyl and host-guest crown ether functionalities is achieved via coordination-driven self-assembly. The host-guest recognition properties of the crown ether moieties and their ability to complex cationic guests to form tris[2]pseudorotaxane complexes are examined and the functional moieties have operated orthogonally, which have resulted in discrete supramolecular hexagons that are capable of carrying out a variety of functions.

A general strategy for the synthesis of stable, multifunctional cuboctahedral complexes in which coordination-driven self-assembly facilitates the precise control over positioning of either ferrocene or crown ether functionalities is presented. The results suggested that the appropriate stoichiometric combination of functionalized 120 [degree] diplatinum acceptor units with tritopic donor units afforded supramolecular cuboctahedra with covalently linked functional groups.

The self-assembly of irregular metallo-supramolecular hexagons and parallelograms is achieved in a self-selective manner upon mixing 120 [degree] unsymmetrical dipyridyl ligands with 60 [degree] or 120 [degree] organoplatinum acceptors in a 1:1 ratio. The polygons are characterized by using [super 31]P and [super 1]H multinuclear NMR spectroscopy and electrospray ionization mass spectrometry and geometric features of the molecular subunits have directed the self-selection process.

A new class of 120 [degree] dendritic di-Pt(II) acceptor subunits is designed and prepared, from which six-component hexagonal metallodendrimers are formed with 120 [degree] dendritic dipyridine donors via [3+3] coordination-driven self-assembly. MMFF force-field simulations have shown that all metallodendrimers have a hexagonal ring with an internal radius of approximately 1.4 nm.

The direct observation of dynamic ligand exchange between Pt-N coordination-driven self-assembled supramolecular polygons is achieved by using stable [super 1]H/[super 2]D isotope labeling of the pyridyl donors and electrospray ionization mass spectrometry. The studies have shown that the exchange is dependent on the temperature, solvent and the counteranions.