Efficient Amide Based Halogenide Anion Receptors

In this paper, we present the synthesis and anion recognition properties of the amide based phenanthroline derivatives 1, 2 and 3. In all cases 1:1 receptor : anion complexes were observed. The receptors were found to be selective for fluoride and chloride respectively over other putative anionic guest species.

Coordination-driven self-assembly of palladium(Ⅱ)-based metallacalixarenes as anion receptors using flexible pyridine-bridged diimidazole ligands

Two types of palladiu m(Ⅱ)-based metallacalixarenes[ML]^(2+)and[ML_(2)]^(2+)have been synthesized through coordination-driven self-assembly from a series of flexible pyridine-bridged diimidazole ligands[2,6-bis((1 H-imidazol-1-yl)methyl)pyridine(L^(1)),2,6-bis((1 H-benzo[d]imidazol-1-yl)methyl)pyridine(L^(2)),2,6-bis((1 H-naphtho[2,3-d]imidazol-1-yl)methyl)pyridine(L^(3))],with palladium(II)-based building blocks[Pd(BF_(4))_(2)(M^(1)-BF_4)and(tmeda)Pd(NO_(3))_(2)(M^(2)-NO_(3))(tmeda=N,N,N',N'-tetramethyl-ethylenediamine)].All complexes were characterized by NMR spectroscopy(^(1)H NMR and^(13)C NMR),mass spectrometry(CSIMS,ESI-HRMS)and elemental analysis.The single crystal X-ray diffraction analysis of[M^(1)L^(2)_2](NO_(3))_(2),[M^(1)L^(3)_2](NO_(3))_(2),[M^(1)L^(3)_2](PF_6)_2 and[M~2 L^(3)](NO_(3))_(2)further confirmed the uniquely single bowl-shape and double bowl-shape structures.The anion binding properties within the metallacalixarenes as receptors were also investigated by NMR titration experiments in DMSO.

Neutral pyrimidine C-H donor as anion receptor

Anion receptors including pyrimidine subunit were designed and synthesized and their binding abilities with various anions were investigated by fluorescence and ~1H NMR titration experiments.DFT calculations provided some information for anion recognition.It is confirmed that both of two new pyrimidine anion receptors have the selectivity for Cl-.

The Synthesis of a Fluorescent Chemosensor Containing Two Thiourea Groups and Its Recognition Behavior for Dicarboxylate Anions

A novel anion receptor2 bearing anthracene flurophore and thiourea was synthesized and identified by1H NMR, MS, IR and elemental analysis. The interaction between receptor2 and various α, ω-dicarboxylate anions was studied by fluorescence spectrum. The obtained fluorescence data indicate that 1∶1 stoichiometry complex is formed between receptor2 with diferent dicarboxylate anions through a hydrogen-bonging interaction. The selectivity of2 for recognition of different dicarboxylates deponds on chain length of the anionic species. Key words anion receptor - fluorescence - synthesis - anion recognition CLC number O 626 Foundation item: Supported by the National Science Foundation of china (20372054)Biography: WANG Fa-jun (1976-), male, Master Candidate, research direction: supramolecular chemistry.

Anion recognition with porphyrin-bottomed tetraurea receptors

Three tetraurea-appended porphyrin derivatives were synthesized and applied as anion receptors to complex with various anions, including F^-, Cl^-, Br^-, I^-, NO3^-, HSO4^-, and AcO^-. The binding stoichiometries were all measured to be 1：1 and high binding abilities of these receptors toward the anions were demonstrated with the association constants of up to 1.1 × 10^8 L/mol. The complexation of the receptors with anions was further unambiguously confirmed by single-crystal X-ray analysis

Influence of terminal substituents on the halide anion binding of foldamer-based receptors

Foldamers 1–4 incorporating different terminal substituents have been designed and synthesized for binding halide anions.~1H NMR titration experiments carried out in DMSO-d_6/CDCl_3（15/85, v/v）demonstrated that the short oligo （aryltriazole）s backbone 1 could not bind halide anions unless that amide H-bond donors were incorporated at the termini of the oligomer. Terminal substituents on oligo（aryltriazoleamide）s foldamers 2–4 display a considerable influence on the binding affinities of the foldamers for halide anions. Large steric hindrance of the terminal substituents was found to be unfavorable for binding halide anions, but aromatic π-π interactions between two terminal substituents are capable of stabilizing the conformation of foldamers thus giving rise to an enhancement in the binding strengths. However, the terminal substituents were found to hardly affect the binding selectivity in the studied cases.

Synthesis of Novel Anionic Receptors with (Thio) urea and Amide Binding Sites and the Recognition Properties for Anions

Two new neutral receptors (1 and 2) containing (thio)urea and amide groups were synthesized by simple steps in good yields. The binding properties for anions of 1 and 2 were characterized by UV-vis and fluorescence spectra. Receptor 1 had an excellent selectivity for AcO - in comparison with other anions. The association constants of 1·AcO - and 2·p-NO_2PhOPO 2- _3 were higher than those of other anions (Cl -,Br -,I -,H_2PO -_4 and p-NO_2PhO -). In particular,an obvious color change was observed from light yellow to golden yellow upon addition of AcO - to the solution of 1 in DMSO. The results of non-linear curve fitting by UV-vis and fluorescence spectral data indicate that a 1∶1 stoichiometry complex is formed between compound 1 or 2 and anions through a hydrogen bonding interaction.

A New Maleamide Bridged Carbazole Chromogenic-sensor Based on Proton Transfer Signaling Mode

A Maleamide bridged carbazole receptor was designed and synthesized, the interactions between the receptor and anions, such as Ac-, H2PO4-, OH-, F-, Cl-, Br- and I- in DMSO were investigated by UV-Vis spectroscopy and 1H NMR titration. The results of UV-Vis spectral studies indicate that interactions existed between receptor and anions, which induced remarkable color changes. The 1H NMR titration indicated amide moiety of the receptor was deprontonated first when a small quantity of anions such as Ac-, H2PO4-, F- were added; however, the carbazole N―H was gradually deprontonated upon the addition of anions.

Anion-induced differential assembly and structural transformation of supramolecular coordination cages

The intimate host-anion interactions will regulate thermodynamics and kinetics in the self-assembly of cationic cages mimicking biological counterparts.Herein,we report construction and transformation of three Pd(Ⅱ)-based metal-organic cages(MOCs)depending on different anions.Stoichiometric conversions of the lantern-shaped MOC-34 into either octahedral MOC-35 or tricapped trigonal prism MOC-36 are induced by BF_(4)^(–)or NO_(3)^(–),respectively.MOC-36 is kinetically favored and can undergo quantitative conversion to the thermodynamically preferred MOC-35 upon heating,accelerated by excess BF_(4)^(–)to motivate dissociative dynamics of Pd-vertices and lower activation barrier of cage transformation.The guest encapsulation behaviors of MOC-35 and MOC-36 have also been tested.These results manifest a significance of host-anion dynamics beyond complementary anion template,shedding light on the understanding of intricate anion recognition in nature.

Synthesis and Enantioselective Discrimination of Chiral Fluorescence Receptors Bearing Amino Acid Units

Two chiral fluorescence receptors （1, 2） were synthesized, and their structures were characterized by IR, ^1H NMR, ^13C NMR, mass spectra and elemental analysis. The chiral recognition of receptors was studied by ^1H NMR and fluorescence spectra. The results demonstrate that receptors and dibenzoyl tartrate anion formed a 1 ： 1 complex. The receptor 1 exhibited a good enantioselective recognition ability toward the enantiomers of dibenzoyl tartrate anion.

Upregulation of Spinal Voltage-Dependent Anion Channel 1 Contributes to Bone Cancer Pain Hypersensitivity in Rats

Voltage-dependent anion channel 1（VDAC1） is thought to contribute to the progression of tumor development. However, whether VDAC1 contributes to bone cancer pain remains unknown. In this study, we found that the expression of VDAC1 was upregulated in the L2–5 segments of the spinal dorsal horn at 2 and 3 weeks after injection of tumor cells into the tibial cavity. Intrathecal injection of a VDAC1 inhibitor significantly reversed the pain hypersensitivity and reduced the over-expression of Toll-like receptor 4（TLR4）. Intrathecal injection of minocycline, an inhibitor of microglia, also attenuated the pain hypersensitivity of rat models of bone cancer pain.These results suggest that VDAC1 plays a significant role in the development of complicated cancer pain, possibly by regulating the expression of TLR4.