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Dian Niu, Lukang Ji, Guanghui Ouyang, Minghua Liu
A naphthalene substituted histidine derivative was found to form an organogel showing circularly polarized luminescence (CPL) and the addition of non-fluorescent achiral benzoic acids could efficiently enhance the CPL via non-covalent interactions.
January 15, 2018: Chemical Communications: Chem Comm
Rong Wang, Yikun Guo, Di Zhang, Huiqiong Zhou, Dahui Zhao, Yuan Zhang
Attaining control on charge injection properties is significant for meaningful applications of organic field-effect transistors (OFETs). Here, molecular electron-doping is applied with an air-stable dimer dopant for n-type OFETs based on (naphthalene diimide-diketopyrrolopyrrole) polymer hosts. Through investigating the doping effect on contact and transport properties, it is found that the electron transport increases in n-doped OFETs at low doping regime with remaining large on/off ratios. These favorable meliorations are reconciled by the mitigated impacts of contact resistance and interfacial traps, as well as the surface morphology exhibiting features of increased ordering...
January 15, 2018: Macromolecular Rapid Communications
Andriy Kuklya, Lokman Coban, Florian Uteschil, Klaus Kerpen, Ursula Telgheder
Direct inlet probe (DIP) was used as an introduction and a pre-separation step for atmospheric pressure photoionization time-of-flight ion mobility spectrometry (APPI-TOF-IMS) for the first time. IMS is an analytical technique used to separate and identify ionized molecules in the gas phase and under atmospheric pressure based on their mobility. The utilization of DIP prior to IMS gives the possibility to introduce the analytes into the gas phase and provides an additional separation based on their vapor pressure...
April 1, 2018: Talanta
Dušan Ž Veljković
Energies of CH/O interactions between water molecule and polycyclic aromatic hydrocarbons with a different number of aromatic rings were calculated using ab initio calculations at MP2/cc-PVTZ level. Results show that an additional aromatic ring in structure of polycyclic aromatic hydrocarbons significantly strengthens CH/O interactions. Calculated interaction energies in optimized structures of the most stable tetracene/water complex is -2.27 kcal/mol, anthracene/water is -2.13 kcal/mol and naphthalene/water is -1...
December 28, 2017: Journal of Molecular Graphics & Modelling
Wannapha Molee, Anuchit Phanumartwiwath, Chatchai Kesornpun, Sanya Sureram, Nattaya Ngamrojanavanich, Kornkanok Ingkaninan, Chulabhorn Mahidol, Somsak Ruchirawat, Prasat Kittakoop
New naphthalene derivatives (1 and 2) and a new isomer (3) of ventilagolin, together with known anthraquinones, chrysophanol (4), physcion or emodin 3-methyl ether (5), and emodin (6), were isolated from vines of Ventilago denticulata. The isolated compounds exhibited cytotoxic activity with IC50 values of 1.15-40.54 μg/mL. Compounds 1-3 selectively exhibited weak antibacterial activity (MIC values of 200.0-400.0 μg/mL), while emodin (6) displayed moderate antibacterial activity with MIC values of 25.0 μg/mL...
January 11, 2018: Chemistry & Biodiversity
Jian Liu, Li Qiu, Riccardo Alessandri, Xinkai Qiu, Giuseppe Portale, JingJin Dong, Wytse Talsma, Gang Ye, Aprizal Akbar Sengrian, Paulo C T Souza, Maria Antonietta Loi, Ryan C Chiechi, Siewert J Marrink, Jan C Hummelen, L Jan Anton Koster
In this contribution, for the first time, the molecular n-doping of a donor-acceptor (D-A) copolymer achieving 200-fold enhancement of electrical conductivity by rationally tailoring the side chains without changing its D-A backbone is successfully improved. Instead of the traditional alkyl side chains for poly{[N,N'-bis(2-octyldodecyl)-naphthalene-1,4,5,8-bis(dicarboximide)-2,6-diyl](NDI)-alt-5,5'-(2,2'-bithiophene)} (N2200), polar triethylene glycol type side chains is utilized and a high electrical conductivity of 0...
January 11, 2018: Advanced Materials
Efres Belmonte-Reche, Marta Martínez-García, Aurore Guédin, Michela Zuffo, Matilde Arévalo-Ruiz, Filippo Doria, Jenny Campos-Salinas, Marjorie Maynadier, Jose-Juan Lopez-Rubio, Mauro Freccero, Jean-Louis Mergny, Jose María Perez-Victoria, Juan Carlos Morales
G-quadruplexes (G4) are DNA secondary structures which take part in the regulation of gene expression. Putative G4 forming sequences (PQS) have been reported in mammals, yeast, bacteria and viruses. Here, we present PQS searches on the genomes of T. brucei, L. major and P. falciparum. We found telomeric sequences and new PQS motifs. Biophysical experiments showed that EBR1, a 29 nucleotide long highly repeated PQS in T. brucei, forms a stable G4 structure. G4 ligands based on carbohydrate conjugated naphthalene diimides (carb-NDIs) which bind G4's including hTel, could bind EBR1 with selectivity versus dsDNA...
January 11, 2018: Journal of Medicinal Chemistry
Hongxing Jia, Yuyue Gao, Qiang Huang, Shengsheng Cui, Pingwu Du
Herein we report a facile three-step synthesis of [8]-, [9]-, and [12]cyclo-1,4-naphthalene nanorings as the conjugated segments of carbon nanotubes. The nanorings were created via a platinum-mediated assembly of 1,4-naphthalene-based units and subsequent reductive elimination in the presence of triphenylphosphine. This present platinum-mediated approach is attractive because of its simple three-step process to produce the targeted nanorings in a high overall yield. In addition, their photophysical properties were studied using UV-vis spectroscopy and photoluminescence (PL) spectroscopy, which further revealed their unique size-dependent properties...
January 11, 2018: Chemical Communications: Chem Comm
Xiangqian Yan, Fanzhi Yang, Guilong Cai, Qingwei Meng, Xiaofang Li
An organo rare-earth metal complex has been employed as a highly efficient nucleophile in Ni(0)-catalyzed C-O bond functionalization. The optimized catalytic system which consists of Ni(cod)2, PCy3, and t-BuONa could smoothly convert 1 equiv of naphthyl ethers to alkylated naphthalene analogues with 0.4 equiv of Ln(CH2SiMe3)3(THF)2, delivering good to excellent yields. The reaction system could also activate the ArCH2-O bond with mild base.
January 10, 2018: Organic Letters
Yang Li, Jianfeng Li, Jianying Zhang, Haibin Song, Chunming Cui
A new strategy for the efficient synthesis of tricy-clo[2,2,0,02,5]hexasilanes R6Si6X2 (R = 2,4,6-Me3C6H2; X = H, Cl) and a bridged tricyclic R6Si6 dianion from the tetrachlorotrisilane RCl2SiSi(H)RSiCl2R (1) is reported. Reduction of 1 with lithium naphthalene afforded tricyclohexasilane R6Si6H2 (2), which reacted with CCl4 to give the dichloride R6Si6Cl2 (3) in almost quantitative yield. Reduction of the dichloride 3 with four equivalents of potassium graphite in the presence of 18-crown-6 afforded the first R6Si6 dianion paired with [K(18-crown-6)]+2 counterions...
January 10, 2018: Journal of the American Chemical Society
T F Headen, P L Cullen, R Patel, A Taylor, N T Skipper
Total neutron scattering has been used in conjunction with H/D and *N/15N isotopic substitution to determine the detailed liquid-state structures of pyridine and naphthalene. Analysis of the data via an empirical potential-based structure refinement method has allowed us to interrogate the full six-dimensional spatial and orientational correlation surfaces in these systems, and thereby to deduce the fundamental effects of a heteroatom and aromatic core-size on intermolecular π-π interactions. We find that the presence of a nitrogen heteroatom, and concomitant dipole moment, in pyridine induces surprisingly subtle departures from the structural correlations observed in liquid benzene: in both cases the most probable local motif is based on perpendicular (edge-to-face) intermolecular contacts, while parallel-displaced configurations give rise to a clear shoulder in the correlation surface...
January 10, 2018: Physical Chemistry Chemical Physics: PCCP
Deep Sankar Pal, Haridas Kar, Suhrit Ghosh
A naphthalene-diimide appended carboxylic acid either spontaneously self-assembles (P) by an open-chain H-bonding or can be arrested in an intra-molecularly H-bonded monomeric state (M) depending on the sample preparation method. Sonication of P produces a seed (S) that triggers controllable supramolecular polymerization (SP) of M via a chain growth route with first order kinetics, a tunable mesoscopic structure and a living nature as demonstrated by the chain-extension up to three cycles. SP of an achiral M, initiated by a chiral S, illustrates chiral amplification by the "sergeant and soldiers" effect...
January 10, 2018: Chemical Communications: Chem Comm
Chang Su Lim, Myoung Ki Cho, Mi Yeon Park, Hwan Myung Kim
Hydrogen peroxide (H2O2) is important in the regulation of a variety of biological processes and is involved in various diseases. Quantitative measurement of H2O2 levels at the subcellular level is important for understanding its positive and negative effects on biological processes. Herein, a two-photon ratiometric fluorescent probe (SHP-Cyto) with a boronate-based carbamate leaving group as the H2O2 reactive trigger and 6-(benzo[d]thiazol-2'-yl)-2-(N,N-dimethylamino) naphthalene (BTDAN) as the fluorophore was synthesized and examined for its ability to detect cytosolic H2O2 in situ...
January 2018: ChemistryOpen
Elisabete Oliveira, Emilia Bértolo, Cristina Núñez, Viviane Pilla, Hugo M Santos, Javier Fernández-Lodeiro, Adrian Fernández-Lodeiro, Jamila Djafari, José Luis Capelo, Carlos Lodeiro
Red and green are two of the most-preferred colors from the entire chromatic spectrum, and red and green dyes are widely used in biochemistry, immunohistochemistry, immune-staining, and nanochemistry applications. Selective dyes with green and red excitable chromophores can be used in biological environments, such as tissues and cells, and can be irradiated with visible light without cell damage. This critical review, covering a period of five years, provides an overview of the most-relevant results on the use of red and green fluorescent dyes in the fields of bio-, chemo- and nanoscience...
January 2018: ChemistryOpen
Majid I Tamboli, Durga Prasad Karothu, Mysore S Shashidhar, Rajesh Ghanshyam Gonnade, Pance Naumov
The pincer-like double ester naphthalene-2,3-diyl-bis(4-fluorobenzoate) (2) is pentamorphic. When crystals of form I are heated to below their melting point (441-443 K) they undergo a phase transition accompanied by a thermosalient effect, a rare and visually striking crystal motility whereby crystals jump or disintegrate. The phase transition and the thermosalient effect are reversible. Analysis of the crystal structure revealed that form I of 2 is a class II thermosalient solid. Crystals of form III also undergo a reversible phase transition in the temperature range 160-170 K, however they are not thermosalient...
January 8, 2018: Chemistry: a European Journal
Zachary X Giustra, Shih-Yuan Liu
Boron-nitrogen heteroarenes hold great promise for practical application in many areas of chemistry. Enduring interest in realizing this potential has in turn driven perennial innovation with respect to these compounds' synthesis. This Perspective discusses in detail the most recent advances in methods pertaining to the preparation of BN-isosteres of benzene, naphthalene, and their derivatives. Additional focus is given to the progress enabled by these syntheses toward functional utility of such BN-heterocycles in biochemistry and pharmacology, materials science, and transition-metal-based catalysis...
January 9, 2018: Journal of the American Chemical Society
A D Şahin, M T Saçan
Toxic potencies of xenobiotics such as halogenated aromatic hydrocarbons inducing 2,3,7,8-tetrachlorodibenzo-p-dioxin/2,3,7,8-tetrachlorodibenzofuran (TCDD/TCDF)-like effects were investigated by quantitative structure-toxicity relationships (QSTR) using their aryl hydrocarbon receptor (AhR) binding affinity data. A descriptor pool was created using the SPARTAN 10, DRAGON 6.0 and ADMET 8.0 software packages, and the descriptors were selected using QSARINS (v.2.2.1) software. The QSTR models generated for AhR binding affinities of chemicals with TCDD/TCDF-like effects were internally and externally validated in line with the Organization of Economic Co-operation and Development (OECD) principles...
January 8, 2018: SAR and QSAR in Environmental Research
Tingting Liu, Ling Zhang, Shutao Wang, Yaoyao Cui, Yutian Wang, Lingfei Liu, Zhe Yang
Qualitative and quantitative analysis of polycyclic aromatic hydrocarbons (PAHs) was carried out by three-dimensional fluorescence spectroscopy combining with Alternating Weighted Residue Constraint Quadrilinear Decomposition (AWRCQLD). The experimental subjects were acenaphthene (ANA) and naphthalene (NAP). Firstly, in order to solve the redundant information of the three-dimensional fluorescence spectral data, the wavelet transform was used to compress data in preprocessing. Then, the four-dimensional data was constructed by using the excitation-emission fluorescence spectra of different concentration PAHs...
December 12, 2017: Spectrochimica Acta. Part A, Molecular and Biomolecular Spectroscopy
Chiara Capacci, Iacopo Ciabatti, Cristina Femoni, Maria Carmela Iapalucci, Tiziana Funaioli, Stefano Zacchini, Valerio Zanotti
The reaction of [NEt4]2[Ni6(CO)12] in thf with 0.5 equiv of PCl3 affords the monophosphide [Ni11P(CO)18]3- that in turn further reacts with PCl3 resulting in the tetra-phosphide carbonyl cluster [HNi31P4(CO)39]5-. Alternatively, the latter can be obtained from the reaction of [NEt4]2[Ni6(CO)12] in thf with 0.8-0.9 equiv of PCl3. The [HNi31P4(CO)39]5- penta-anion is reversibly protonated by strong acids leading to the [H2Ni31P4(CO)39]4- tetra-anion, whereas deprotonation affords the [Ni31P4(CO)39]6- hexa-anion...
January 5, 2018: Inorganic Chemistry
Jian Jun Liu, Ying Dong, Li Zhen Chen, Ling Wang, Shu Biao Xia, Chang Cang Huang
Naphthalenediimides, a class of organic dyes with an expanded π-electron-deficient plane, have attracted considerable interest because of their photoinduced electron transfer from neutral organic moieties to stable anionic radicals. This makes them excellent candidates for organic linkers in the construction of photochromic coordination polymers. Such a photochromic two-dimensional coordination polymer has been prepared using N,N'-bis(pyridin-4-ylmethyl)naphthalene-1,8:4,5-bis(dicarboximide) (DPMNI). In crystallization tubes, upon slow diffusion of an MeOH solution of cadmium perchlorate into a CHCl3 solution of DPMNI, the complex poly[[bis[μ2-2,7-bis(pyridin-4-ylmethyl)benzo[imn][3,8]phenanthroline-1,3,6,8(2H,7H)-tetrone-κ2N:N']bis(perchlorato-κO)cadmium(II)] chloroform tetrasolvate], {[Cd(C26H16N4O4)2(ClO4)2]·4CHCl3}n, (I), was obtained...
January 1, 2018: Acta Crystallographica. Section C, Structural Chemistry
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