ABSTRACT
In this study, four isostructural pillar-layered frameworks were constructed using a porphyrin layer and an anthracene pillar, which served as the sensitizer and annihilator, respectively, in the triplet-triplet annihilation upconversion (TTA-UC) system. Framework 1 demonstrated the highest upconversion quantum yield of 1.01%. Additionally, 1 and 2 also exhibited down-conversion fluorescence resulting from the porphyrin component. A twist intramolecular charge transfer (TICT) state was observed in the bianthracene chromophore of 2, resulting in transient rotation of two anthracene rings and red-shifted emission. Both computational studies and experiments confirmed the transition from a locally excited state to a TICT state upon the inclusion of polar guest molecules into the framework.
ABSTRACT
The synthesis and characterization of porphyrin center regulated three-dimensional covalent organic frameworks (COFs) with 2-fold interpenetrated scu or sqc topology have been investigated. These COFs exhibit unique structural features and properties, making them promising candidates for photocatalytic applications in CO2 reduction and artemisinin synthesis. The porphyrin center serves as an anchor for metal ions, allowing precise control over structures and functions of the frameworks. Furthermore, the metal coordination within the framework imparts desirable catalytic properties, enabling their potential use in photocatalytic reactions. Overall, these porphyrin center regulated metal-controlled COFs offer exciting opportunities for the development of advanced materials with tailored functionalities.
ABSTRACT
A series of luminescent frameworks was synthesized from the selective combination of aggregation induced emission (AIE)-linker tetra-(4-carboxylphenyl)ethylene (H4 TCPE) and Zn2+ . Complex 1 was formed by the close packing of Zn-TCPE hinge, and isostructural complexes 2-5 were constructed by the linkage of Zn-TCPE layer and pillar ligands. These complexes exhibit highly efficient multiphoton excited photoluminescence (MEPL) and concomitant third-harmonic generation (THG). The multiphoton absorption (MPA) parameters of 1 are superior to other multiphoton emission materials including the perovskite nanocrystals. The incorporation of pillar linkers slows down the charge transfer between layers of Zn-TCPE, and the aromatic core of pillar linkers has a great influence on the MPA performance of the corresponding frameworks.
ABSTRACT
A series of triangular metallaprisms with a kinetically inert Pt-N bond have been synthesized from the stepwise assembly of a Pt-corner, linear linker 4,4'-bipy (4,4'-bipy = 4,4'-bipyridine) and triangular ligand [tpb or tpt, tpb = tris(4-pyridyl)benzene, tpt = tris(4-pyridyl)triazine]. The use of an unsymmetrical [Pt(HL)]-corner (H2L = 2,6-diphenylpyridine) leads to novel isostructural products. Phenyl rotation at the metal-corners endows these complexes with good aggregation-induced emission (AIE) function, with varied activities across the isostructural complexes. The coordination sequence of electron-deficient ligand tpt also imparts significant influence on the complex emission. These organoplatinum triangular metallaprisms thus provide a good model to study the influence of building blocks and coordination sequence on the luminescence of supramolecules.
ABSTRACT
To investigate the antitumor mechanism of artemisninin, a flexible docking analysis was used to score all kinds of functions of 11 Qinghaosu derivatives and transferrin with different resolutions. The distances of Asp-63, Tyr-188, His-249, Arg-124 and Lys-296 with Qinghaosu were less than 0.5 nm, separately. Meanwhile, the higher is the activity of Qinghaosu derivatives the higher is the score. Our model explains that Fe2+ is more feasible to react with Qinghaosu, and not involved in other metabolism in presence of transferrin. Docking results unveil that Iron(II)-transferrin increased the cytotoxicity of Qinghaosu derivatives and provide a rational basis for further design and synthesis of novel Qinghaosu derivatives.
Subject(s)
Antineoplastic Agents, Phytogenic/chemistry , Artemisinins/chemistry , Drug Discovery , Models, Chemical , Transferrin/chemistry , Antineoplastic Agents, Phytogenic/chemical synthesis , Antineoplastic Agents, Phytogenic/pharmacology , Artemisinins/chemical synthesis , Artemisinins/pharmacology , Catalytic Domain , Molecular Structure , Protein BindingABSTRACT
We developed a metalloligand strategy to construct porous frameworks, viz. the combined use of IrIII -based octahedral metalloligands and the linear unit [Ni(cyclam)] easily afforded two isostructural complexes 1 and 2 with primitive cubic frameworks. Both complexes show good CO2 /N2 separation property.
ABSTRACT
A series of trapezoidal metallacycles were synthesized by the selective combination of a rigid with a flexible arm. [2]Catenane 3 was obtained by self-assembly when the cavity size of the trapezoidal rings was optimised.
ABSTRACT
There are no reports on the relationship between familial medullary thyroid carcinoma (FMTC) associated with cutaneous amyloidosis (CA) and RET or OSMR/IL31RA gene mutations. In this study, we investigated a Chinese family with FMTC/CA and found a recurrent RET c.2671T>G (p.S891A) mutation in six of 17 family members. Three of the six p.S891A mutation carriers presented with medullary thyroid carcinoma (MTC). Of them, three (two with and one without MTC) were diagnosed as having combined lichen/macular biphasic CA. We also identified a novel RET variant, c.1573C>T (p.R525W) in five members. Of them, three carriers had no evidence of thyroid/skin or basal serum/stimulated calcitonin abnormalities. In vitro cell proliferation assay indicated that oncogenic activity of RET p.S891A was slightly enhanced by p.R525W, whereas p.R525W alone had no effect on cell proliferation. Meanwhile, we identified a novel OSMR variant, c.1538G>A (p.G513D) in seven members. We noticed that three OSMR p.G513D carriers presenting with CA also had the RET p.S891A mutation. Our investigation indicated that the RET p.S891A mutation combined with OSMR p.G513D may underlie a novel phenotype manifesting as FMTC and CA.