Zaoying Li

Phosphorescent Cu(I) complexes based on bis(pyrazol-1-yl-methyl)-pyridine derivatives for organic light-emitting diodes†

Mononuclear Cu(I) complexes based on bis(pyrazol-1-yl-methyl)-pyridine derivatives and ancillary triphenylphosphine have been prepared and characterized by 1H NMR, mass spectroscopy and single-crystal X-ray analysis. The thermogravimetric analysis shows that the complexes exhibit high thermal stability. The electronic absorption spectra display two features in the regions of 230–260 and 290–350 nm attributable to mixed ligand-to-ligand (LLCT) and metal-to-ligand-charge-transfer (MLCT) excited states, which is supported by the results of density functional theory (DFT) and time-dependent DFT (TDDFT) calculations on these Cu(I) complexes. These complexes are strongly emissive in the solid state at ambient temperature. Intense blue or green emission in the poly(methyl methacrylate) film is observed in the region of 475–518 nm for these complexes with the emission lifetimes in the microsecond time scale (12–20 μs), indicating that the emission may be phosphorescence emission. Increasing the steric hindrance of the substituents on the pyrazole unit results in a blue-shift of the emission bands and enhanced emission quantum efficiency in PMMA films. The two most emissive complexes have been used for the fabrication of phosphorescent organic light-emitting diodes (POLEDs).

Synthesis and in vitro and in vivo evaluation of manganese(III) porphyrin-dextran as a novel MRI contrast agent.

5-(4-Aminophenyl)-10,15,20-tris(4-sulfonatophenyl) manganese(III) porphyrin conjugated with dextran was synthesized. Its potential of being used as a tumor-targeting magnetic resonance imaging contrast agent was evaluated in vitro and in vivo. The results demonstrated that the compound has a longitudinal relaxivity (R(1)) higher than Gd-DTPA, low cytotoxicity and binding specificity to tumor cell membrane.

A Simple Colorimetric and Fluorescent Anion Sensor Based on 4-Amino-1,8-naphthalimide: Synthesis and its Recognition Properties

A neutral 4-amino-1,8-naphthalimide-based anion receptor 1 containing a thiourea binding site was synthesized by simple steps. Its recognition capabilities for various anions were investigated by UV–vis, fluorescence and 1H NMR spectra, which showed that compound 1 could effectively and selectively recognize F− and AcO− over other anions (Cl− , Br− , I− , , , ). In particular, a moderate color change (from greenish yellow to bright yellow) and significant fluorescence quenching were synchronously observed upon addition of F− or AcO− . Nonlinear curve fitting and Job plot method established the formation of 1:1 hydrogen-bonding complex between compound 1 and the bound anions.

Dipyrrolylquinoxaline-bridged Schiff bases: a new class of fluorescent sensors for mercury(II)

Novel 2,3-bis(1H-pyrrol-2-yl)quinoxaline-functionalized Schiff bases were prepared and characterized as new fluorescent sensors for mercury(II) ion. The X-ray crystal structures of compounds 4, 5, 4a and 5a were determined. The binding properties of 4 and 5 for cations were examined by UV-vis and fluorescence spectroscopy. The UV-vis and fluorescence data indicate that a 1 : 1 stoichiometric complex is formed between compound 4 (or 5) and mercury(II) ion, and the association constant is (3.81 +/- 0.7) x 10(5) M(-1) for 4 and (3.43 +/- 0.53) x 10(5) M(-1) for 5. The recognition mechanism between compound 4 (or 5) and metal ion was discussed based on their chemical construction and the fluorescence quenching effect when they interact with each other. Competition experiments revealed that compound 4 (or 5) has a highly selective response to mercury(II) ion in aqueous solution.

Synthesis and structure of novel disulfide(trisulfide)-containing thiophenes

Abstract A novel trisulfide‐containing thiophene, 1,5‐dihydrothieno[3,4‐e][1,2,3]trithiepine (5), and a disulfide analogue, 1,4‐dihydrothieno[3,4‐d][1,2]dithiine (4), were designed and synthesized. All the compounds were characterized by FT‐IR, NMR, Raman, MS, and elemental analysis, some of which were confirmed by single‐crystal structure analysis. The designed molecules have potential usage as the cathode material for batteries.

Photocytotoxicity, cellular uptake and subcellular localization of amidinophenylporphyrins as potential photodynamic therapeutic agents: An in vitro cell study

The cell-based studies of 5, 10, 15, 20-Tetrakis (4-amidinophenyl) porphyrin (Por1), its Zn complex (Por2) and amidinophenyl bisporphyrin (Por3) were carried out to examine their photocytotoxicity, cellular uptake and sub-cellular localization with human nasopharyngeal carcinoma cell (HK-1), using 5, 10, 15, 20-Tetrakis (N-methyl-4-pyridyl) porphyrin (H2TMPyP) as a reference. These porphyrins showed low dark-cytotoxicity and high photo-cytotoxicity against HK-1. The amphiphilic amidinophenyl bisporphyrin (Por3) displayed better cellular uptake than the single hydrophilic Por1, Por2 and H2TMPyP. As seen from the extent of overlapping of the fluorescence profiles, lysosomal localization of amidinophenylporphyrin Por1-Por3 and mito/lyso localization of the H2TMPyP occurred in the cells. The results suggest these porphyrins with amidine group could be used as potential agents in photodynamic therapy.

Synthesis and Structure of a Novel Disulfide‐Containing Aniline

Abstract A novel disulfide‐containing aniline, 5,8‐dihydro‐1H,4H‐2,3,6,7‐tetrathia‐anthracen‐9‐ylamine (6) was synthesized. The structures of the target compound and the intermediates have been identified by 1H NMR, MS, IR, Raman and elemental analysis. In addition, the structure of 9‐Nitro‐5,8‐dihydro‐1H,4H‐2,3,6,7‐tetrathia‐anthracene (5) was determined by single X‐ray analysis.

Synthesis, singlet oxygen generation, photocytotoxicity and subcellular localization of azobisporphyrins as potentially photodynamic therapeutic agents in vitro cell study

Three azobisporphyrins (Por1, Por2 and Por3) were synthesized by coupling two molecules of (4-nitrophenyl/pyridyl) porphyrins in the presence of KOH/butanol. The structures of porphyrins were confirmed by UV, IR, NMR and mass spectra and elemental analysis. With tetraphenylporphyrin (H2TPP) as a control, the singlet oxygen (1O2) generation of porphyrins was evaluated through 1,3-diphenylisobenzofuran (DPBF) method. The order of ability to generate 1O2 for three azobisporphyrins was Por 1 ≈Por 2 > Por 3 ≈ H2TPP. The photocytotoxicity and sub-cellular localization of azobisporphyrins over Hela cells were studied through MTT analysis and confocal laser scanning microscope, respectively. The results indicated Por 1 and Por 2 displayed the low dark-cytotoxicity, while Por 3 induced a concentration-dependent cytotoxicity to Hela cells with the concentration of porphyrins ranging from 1 to 100 μ M. With the light dose at 4 J/cm2, Por 3 killed more than 60% Hela cells at 2 μ M, indicating a high photocytoxicity. As seen from the laser scanning confocal microscopy images, Por 3 was mainly localized in cell membrane, while Por 1 and Por 2 do not displayed significant fluorescent emission in Hela cells. These results suggest the synthesized cationic azobisporphyrin could be used as a potential therapeutic agent for photodynamic therapy of cancers.

Methylene violet 3RAX-conjugated porphyrin for photodynamic therapy: synthesis, DNA photocleavage, and cell study

A methylene violet 3RAX-conjugated porphyrin has been designed and synthesized as a potential photosensitizer in photodynamic therapy because of its high DNA binding constant and the efficacy in inhibiting cancer cells with subcellular localization.

Synthesis and Structure of a Novel Alkynyl-Containing Disulfide Compound as Cathode Materials for Secondary Lithium Batteries

Abstract A novel alkynyl-containing disulfide compound, 5,8-dihydro-1H,4H-2,3,6,7-tetrathia-anthracen (TMSEDTTA), was synthesized. The structures of the target compound and the intermediates have been identified by 1H NMR, 13C NMR, mass spectrometry, Fourier-transform infrared, Raman spectra, x-ray photoelectron spectroscopy, and elemental analysis. In addition, the structure of (Z)-(1,2-dibromo-2-(2,3,5,6-tetrakis(bromomethyl)phenyl)vinyl)trimethylsilane (5) was determined by single x-ray analysis. [Supplementary materials are available for this article. Go to the publishers online edition of Synthetic Communications® for the following free supplemental resource(s): Full experimental and spectral details.] GRAPHICAL ABSTRACT