Synthesis and photodynamic properties of amphiphilic A3B-phthalocyanine derivatives bearing N-heterocycles as potential cationic phototherapeutic agents

Unsymmetrically substituted A₃B-phthalocyanine derivatives bearing annulated 6-membered N-heterocycles, pyridine and pyrazine rings, were synthesized by the ring expansion reaction of boron(III) subphthalocyanine chloride. A geometrically constrained subphthalocyanine unit was reacted with a range of 1,2-phthalonitrile derivatives in presence of 8-diazabicyclo[5.4.0]undec-7-ene to form the A₃B-phthalocyanine. The reactions were carried out in DMSO/1-chloronaphthalene at 130-140 °C for 15 h. This synthetic strategy resulted in phthalocyanines in 37-42% yield that required only simple purification. Annulated 6-membered N-heterocycles were methylated to obtain cationic Zn(II)phthalocyanine derivatives. The spectroscopic and photodynamic properties of these photosensitizers were studied in N,N-dimethylformamide solution. Antifungal activity photoinduced by these compounds was evaluated in Candida albicans cellular suspensions. The results indicate that amphiphilic cationic phthalocyanines represent interesting agents with potential applications in photodynamic inactivation of microorganisms.     

Comparison of the killing effects between nitrogen-doped and pure TiO2 on HeLa cells with visible light irradiation

The killing effect of nitrogen-doped titanium dioxide (N-TiO₂) nanoparticles on human cervical carcinoma (HeLa) cells by visible light photodynamic therapy (PDT) was higher than that of TiO₂ nanoparticles. To study the mechanism of the killing effect, the reactive oxygen species produced by the visible-light-activated N-TiO₂ and pure-TiO₂ were evaluated and compared. The changes of the cellular parameters, such as the mitochondrial membrane potential (MMP), intracellular Ca²⁺, and nitrogen monoxide (NO) concentrations after PDT were measured and compared for N-TiO₂- and TiO₂-treated HeLa cells. The N-TiO₂ resulted in more loss of MMP and higher increase of Ca²⁺ and NO in HeLa cells than pure TiO₂. The cell morphology changes with time were also examined by a confocal microscope. The cells incubated with N-TiO₂ exhibited serious distortion and membrane breakage at 60 min after the PDT.     

Recent progress in synthesis,growth mechanisms,properties, and applications of silicon nitride nanowires

With advances in nanotechnology, nanowires have gained worldwide attention because of their novel properties and promising applications. Among them, silicon nitride (Si₃N₄) nanowires have attracted increasing attention due to their excellent performance and huge application potential. In this review, various synthesis methods of Si₃N₄ nanowires are introduced in detail, and then the growth mechanisms are also stated. Subsequently, the novel properties of Si₃N₄ nanowires including mechanical, optical, electrical, thermal, and wetting performance are highlighted. Applications corresponding to performance are also summarized later, such as composites, field emitters, field-effect transistors (FETs), photodetectors, photocatalysts, and microwave absorbers. Finally, the contents of this article are concluded and outlooks of future research directions are stated. This article reviews the recent advances and provides the prospects and challenges of Si₃N₄ nanowires.     

Measurement and thermodynamic modeling of partition coefficients in N,N-dimethylacetamide-water-carbon dioxide system

The partition coefficients of N,N-dimethylacetamide (N,N-DMA) between the water and the supercritical and near-critical carbon dioxide (CO₂) phases were measured in the temperature range of 298.15-328.15 K and the pressure range of 8.3-24.1 MPa. The measurements were carried out in a 56 ml vessel by contacting the carbon dioxide and the aqueous phases. The partition coefficients of N,N-DMA increased from 0.05 to 0.150 with increasing pressure at a constant temperature and increased with temperature at a constant density. The bubble point pressures of N,N-DMA-CO₂ mixtures were measured at 298.15 K, 308.15 K and 318.15 K and were found to increase with increasing mole fraction of CO₂. The partition coefficients were modeled using the Peng-Robinson Equation of State (PREOS) combined with modified van der Waals mixing rule. The binary interaction parameters for the CO₂-H₂O pair were taken from the literature and were regressed for CO₂-N,N-DMA and H₂O-N,N-DMA pairs by fitting partition coefficients data. The binary interaction parameter for CO₂-N,N-DMA pair was found to depend linearly on temperature. The bubble point pressures of N,N-DMA and CO₂ were also measured and could be predicted fairly well using the regressed binary interaction parameters.     

The synthesis and characterization of ethylenediamine-modified Elsinochrome A

To overcome the lack of appreciable absorption in the phototherapeutic window (600-900 nm) of the naturally occurring perylenequinonoid pigment, Elsinochrome A, which limits its clinical application, an ethylenediamine-modified elsinochrome A, possessing long wavelength absorption (708 nm) was synthesized. Electron paramagnetic resonance and chemiluminescence assays indicated that ethylenediamine-modified Elsinochrome A possessed photosensitizing activity and its photodamage efficacy is greater than that of unmodified Elsinochrome A.     

High-pressure synthesis,crystal structure,and physical properties of NaAlB14 single crystals

Pure NaAlB₁₄ single crystals were successfully synthesized directly from Na, Al, and B at high pressure and high temperature, different from the previously reported method, that is, synthesized from Na₂B₄O₇, Al, and B. The growth of NaAlB₁₄ single crystals was promoted by increasing the reaction temperature. The atomic structures of NaAlB₁₄ single crystal along the [100], [010], [001], and [021] axes were characterized by using a scanning transmission electron microscope. The Raman spectra of NaAlB₁₄ were investigated theoretically and experimentally, and they showed the expected oscillations of the covalent framework. In addition, photoluminescence spectra indicated that NaAlB₁₄ is a semiconductor luminescence material with red (1.68 eV) and near-infrared (1.50 and 1.36 eV) emission characteristics. The band structure revealed that NaAlB₁₄ is an indirect band gap semiconductor with a wide band gap of 2.22 eV.     

Recent progress in synthesis,growth mechanisms,and electromagnetic wave absorption properties of silicon carbide nanowires

With the research and development of nanomaterials, one-dimensional (1D) nanowire structures have received a lot of attention due to their unique physical and chemical properties. Among them, silicon carbide nanowires (SiC NWs) have low density, excellent oxidation resistance, dielectric properties, and electromagnetic (EM) wave absorption properties, which can well meet the development needs of civilian equipment and military weaponry. SiC NWs have outstanding research and application potential in the field of EM wave absorption. However, comprehensive summaries of SiC NWs have not been available so far. Based on this, this paper reviews the research progress of SiC NWs microwave absorbing materials, various micro-morphologies of SiC NWs are introduced in detail, as well as diverse preparation strategies and multiple growth mechanisms are also stated. Ultimately, recent advances in research progress of SiC NWs and their composites in EM wave absorption are elaborated, along with the future research directions of SiC NWs in the field of EM wave absorption.     

卟啉及其衍生物的合成研究进展

按卟啉母核的不同合成方法,介绍了从各种小分子的缩合而合成卟琳的方法包括经典的Alder-Long法、Lindsey法和新颖的[2 2]法、[3 1]法、线形四吡咯出发合成卟啉、2_位取代吡咯合成卟啉,这些方法能够合成许多不同结构的卟啉化合物.     

The synthesis, crystal structures and photophysical properties of a series of novel 4,6-diphenyl-1,9-anthrazolines

The synthesis and properties of a series of nine new 4,6-diphenyl-1,9-anthrazolines molecules 1a-1i are reported. Compounds 1a-1i were synthesized by Friedländer condensation of 4,6-dibenzoyl-1,3-phenylenediamines and acetyl-functionalized compounds in the presence of polyphosphoric acid as catalyst, in yields ranging from 60% to 94%. The 4,6-diphenyl-1,9-anthrazolines are thermally robust with high decomposition temperatures (>371.0 °C) and high melt transitions (215.1-322.8 °C). Compounds 1a and 1f crystallized in the triclinic system with the space groups P-1. All of them show the lowest energy absorption bands (λ_max^Abs: 397-454 nm), revealing low optical band gaps (2.55-3.00 eV). The compounds emit blue fluorescence with λ_max^Em ranging from 432 to 493 nm in dilute toluene solution. 4,6-Diphenyl-1,9-anthrazolines 1a-1i have a formal reduction potential in the range −1.02 to −1.19 V (versus SCE) and estimated electron affinities (LUMO levels) of 3.21-3.38 eV. These results demonstrate that the new 4,6-diphenyl-1,9-anthrazolines are promising thermally stable n-type semiconductors for organic electronics.     

TMP、Di-TMP和MCF合成工艺进展

三羟甲基丙烷（TMP）是一种含有α-羟甲基的新戊基结构的多元醇,可广泛用于涂料、润滑油、聚氨酯和增塑剂等.双三羟甲基丙烷（Di-TMP）作为三羟甲基丙烷的高附加值深加工产品,具有比TMP更加优越的性能,尤其在航空润滑油方面具有更加独特的性能.三羟甲基丙烷单环缩甲醛（MCF）作为三羟甲基丙烷的高附加值深加工产品,主要用于生产光固化剂、涂料、树脂和特殊油墨以及PVC稳定剂和润滑脂.作者介绍了三羟甲基丙烷、双三羟甲基丙烷和三羟甲基丙烷单环缩甲醛的不同合成方法及反应机理,并提出了关于三羟甲基丙烷、双三羟甲基丙烷和三羟甲基丙烷单环缩甲醛的发展建议.     

The synthesis and two-photon excited fluorescence properties of novel branched fluorene derivatives

Two novel, V-shaped fluorene derivatives branched from triphenylamine and their linear analogue were synthesized via Cu-mediated Ullmann condensation and subsequent Pd-catalyzed Heck coupling reaction. Their two-photon excited fluorescence properties as well as their linear absorption and single-photon excited fluorescence properties were examined. When excited at 730 nm by a Ti:sapphire femtosecond laser, the compounds exhibited strong two-photon excited blue fluorescence. The two-photon excited fluorescence cross-sections of V-shaped derivatives in toluene at 730 nm were 506 GM in the case of N, N-bis{7-[4′-(N, N-diphenylamino)styryl]-9,9-diethyl-9H-fluorene-2-yl}-aniline) and 397 GM for N, N-Bis{7-[4′-(N, N-diphenylamino)styryl]-9,9-diethyl-9H-fluorene-2-yl}-4-acetyl-aniline), respectively.     

The synthesis,photophysical and electrochemical properties of a series of novel 3,8,13-substituted triindole derivatives

The synthesis and properties of a series of new 3,8,13-substituted triindole derivatives 1a–1e are reported. The 3,8,13-substituted triindoles were thermally robust with high decomposition temperatures (≥405 °C) and high melt transitions (219 °C–373 °C). Compound 5e was crystallized in the monoclinic system with the space group P2₁/n. These compounds showed UV–Vis absorption (λ_max^Abs) in the range of 311–345 nm in DCM solution and 371–391 nm in solid state, and fluorescence maxima (λ_max^Em) in the range of 394–412 nm in DCM solution and 416–461 nm in solid state. The fluorescence quantum yields ranged from 0.27 to 0.58. The estimated electron affinities (LUMO levels) and estimated ionization potential (HOMO levels) of compounds 1a–1e are 3.54–3.71 eV and 5.12–5.48 eV, respectively. Quantum chemical calculations using DFT B3LYP/6-31G showed nearly identical LUMO (−0.72 to −1.10 eV) and HOMO (−4.65 to −4.84 eV) values. These results demonstrated that the new 3,8,13-substituted triindoles are promising thermally stable host materials for organic light-emitting diodes with reasonable hole mobility.     

Synthesis, absorption and fluorescence properties of N-triazinyl derivatives of 2-aminoanthracene

N-(4,6-dichloro-1,3,5-triazin-2-yl)-2-aminoanthracene was synthesized by substitution of one chlorine atom of 2,4,6-trichloro-1,3,5-triazine with 2-aminoanthracene. A new series of N-triazinyl-2-aminoanthracenes was prepared by nucleophilic substitution of one or both chlorine atoms on N-(4,6-dichloro-1,3,5-triazin-2-yl)-2-aminoanthracene with electron-donating methoxy or phenylamino groups. The UV/Vis absorption, fluorescence and excitation spectra as well as the fluorescence quantum yields of the prepared compounds were measured in 1,4-dioxane, ethyl acetate, dibutyl ether and acetonitrile; nanosecond kinetics of the fluorescence decay was measured in different solvents. The influence of the character of the substituent on triazinyl ring and of the solvent polarity upon the absorption and fluorescence spectra and fluorescence quantum yields are discussed.     

Design, synthesis, and antiviral properties of 2-aryl-1H-benzimidazole-4-carboxamide derivatives

A series of new benzimidazole derivatives were designed and synthesized. Their chemical structures were testified by 1H NMR, infrared spectroscopy (IR), mass spectrography (MS), and elemental analysis. Their potent antiviral properties indicated the prospect of new drugs. Compound 13, 16, 18, 19, 21, 22, and 23 were identified as novel antivirus with much better selective activity and inhibitory activity than the comparable ribavirin against Coxsackie virus B₃ in VERO cells.     

生物催化在手性化合物合成中的应用

介绍了生物催化手性化合物合成中使用的催化剂种类,生物催化手性合成方法在手性药物、手性化妆品及其它手性化合物合成中的应用,展望了这一方法在手性化合物合成方面的前景。     

The synthesis,optical properties and x-ray crystal structure of novel 1,3,4-oxadiazole derivatives carrying a thiophene unit

Novel, 1,3,4-oxadiazole derivatives carrying a thiophene unit were synthezised and their structures confirmed by elemental analysis, FT-IR and ¹H NMR. UV–vis absorption and photoluminescence spectroscopy revealed emission peaks located between 427 and 437 nm; the measured absorption λ_max and emission λ_em reflected the electron-donor character of the 1,3,4-oxadiazole derivatives. The crystal structure of one of the compounds was investigated.     

The synthesis and characterisation of some fluorinated aliphatic,aliphatic and aliphatic ether polycarbonates

The synthesis and characterisation of ten fluorinated aliphatic, aliphatic and aliphatic ether polycarbonates is described using polycondensation of the appropriate biscarbonates. The materials have been characterised by elemental and spectroscopic analysis, and their T_g values obtained and discussed.     

The synthesis,spectroscopy, electrochemistry and photophysical properties of novel,sandwich europium(III) complexes with a porphyrin ligand bearing four pyrenyl groups in meso-positions

Novel, metal free porphyrins containing four pyrenyl groups in the meso-positions were used to provide novel, sandwich-type mixed tetrapyrrole europium double- and triple-deck complexes. The sandwich-type complexes together with the metal free porphyrin were characterized using electronic absorption, IR and ¹H NMR spectroscopy in addition to elemental analysis. The electrochemical behaviour of the sandwich complexes was investigated by cyclic voltammetry and differential pulse voltammetry in CH₂Cl₂, their photophysical properties were studied in comparison to those of the metal free porphyrin ligand. Fluorescence quenching observed was tentatively attributed to efficient and rapid energy transfer from the pyrenyl groups to porphyrin followed by electron transfer from porphyrin to phthalocyanine.     

Addition of alkyllithiums to 3H-quinazoline-4-thione and various substituted quinazoline derivatives; application in synthesis

Reaction of 3H-quinazoline-4-thione (1) with two mole equivalents of an alkyllithium (t-BuLi, n-BuLi or MeLi) at?78 ^°C in dry THF gave the corresponding 2-alkyl-1,2-dihydro-3H-quinazoline-4-thione (4, 5 or 6) in high yield. Similarly, reactions of 4-(methylthio)quinazoline (7), 4-(ethylthio)quinazoline (8) and 4-methoxyquinazoline (9) with alkyllithiums (one mole equivalent) gave the corresponding 4-substitued 2-alkyl-1,2-dihydroquinazolines 11–18. On the other hand, blocking position 2 with a phenyl group in 4-(methylthio)-2-phenylquinazoline (20) and 4-methoxy-2-phenylquinazoline (21) resulted in reaction with two mole equivalents of alkyllithiums to give 4,4-dialkyl-2-phenyl-3,4-dihydroquinazolines 22–24.     

Scope in the synthesis and properties of poly(ether imide)s

This paper reviews methods of synthesis of dianhydrides for use in poly(ether imide) syntheses. It discusses the synthesis of new dianhydrides from alkyl-substituted diols, catechol and its derivatives and dihydroxynaphthalenes and the synthesis of new poly(ether imide)s from them. The major features of the properties of these groups of polymers, especially those of highly processable poly(ether imide)s, are discussed and potential applications are considered.