59965-20-7Relevant academic research and scientific papers
Large Faraday Rotation in Optical-Quality Phthalocyanine and Porphyrin Thin Films
Nelson, Zachary,Delage-Laurin, Leo,Peeks, Martin D.,Swager, Timothy M.
supporting information, p. 7096 - 7103 (2021/05/29)
The magneto-optical phenomenon known as Faraday rotation involves the rotation of plane-polarized light as it passes through an optical medium in the presence of an external magnetic field oriented parallel to the direction of light propagation. Faraday rotators find applications in optical isolators and magnetic-field imaging technologies. In recent years, organic thin films comprised of polymeric and small-molecule chromophores have demonstrated Verdet constants, which measure the magnitude of rotation at a given magnetic field strength and material thickness, that exceed those found in conventional inorganic crystals. We report herein the thin-film magnetic circular birefringence (MCB) spectra and maximum Verdet constants of several commercially available and newly synthesized phthalocyanine and porphyrin derivatives. Five of these species achieved maximum Verdet constant magnitudes greater than 105 deg T-1 m-1 at wavelengths between 530 and 800 nm. Notably, a newly reported zinc(II) phthalocyanine derivative (ZnPc-OT) reached a Verdet constant of -33 × 104 deg T-1 m-1 at 800 nm, which is among the largest reported for an organic material, especially for an optical-quality thin film. The MCB spectra are consistent with resonance-enhanced Faraday rotation in the region of the Q-band electronic transition common to porphyrin and phthalocyanine derivatives, and the Faraday A-term describes the electronic origin of the magneto-optical activity. Overall, we demonstrate that phthalocyanines and porphyrins are a class of rationally designed magneto-optical materials suitable for applications demanding large Verdet constants and high optical quality.
The synthesis and dielectric properties of a new phenylbenzoate-based calamitic liquid crystal
Ahlatc?o?lu ?zerol, Esma,Ocak, Hale,Bilgin Eran, Belk?z,Karavelio?lu, Selvi
, p. 225 - 232 (2020/08/10)
The dielectric investigation has a great importance in liquid crystal studies as a supportive method to DSC for a complete characterization of liquid crystals as well as in the electronic applications. In this study, the synthesis, mesomorphic characterization and dielectric properties of a new phenylbenzoate-based three-ring calamitic liquid crystal which composed of ester linking groups, (S)-3,7-dimethyloctyloxy chiral unit at one of terminals and n-octyloxy chain at the other end of the molecule, have been reported. The new calamitic liquid crystal 4-[4-((S)-3,7-dimethyloctyloxy)phenoxy)carbonyl]phenyl 4-(n-octyloxy)benzoate (DPCPB) has been characterized using 1H, 13C-NMR and MS-QTOF. The liquid crystalline behavior of the target compound has been investigated by differential scanning calorimetry and optical polarizing microscopy. DPCPB exhibits an enantiotropic non-tilted smectic mesophase in a wide temperature range. The real and imaginary dielectric constant, conductivity mechanism, impedance and dielectric relaxation mechanism of DPCPB have been investigated depending on frequency at different temperatures.
Extraordinary magnetic field effects on the LC phases of homochiral and racemic 4-cyanoresorcinol-based diamagnetic bent-core mesogens
Ocak, Hale,Bilgin Eran, Belk?z,Nuray, Sevgi,?zkonstanyan, Aykun,Poppe, Silvio,Tschierske, Carsten
, p. 1895 - 1910 (2021/03/01)
4-Cyanoresorcinol based bent-core compounds combining one branched chiral with one achiral linear end-chain have been synthesized in enatiomerically pure and one compound also in racemic form. All homochiral compounds form a chiral cybotactic nematic phase at relatively low temperature with a selective reflection ranging from the near IR to near UV. For the compound with the longest chains superparaelectric and antiferroelectric switching smectic phases were observed, whereas the corresponding racemate is non-polar. This is attributed to sterically induced polarization by the denser packing of uniform enantiomers due to chirality synchronization of the helical conformers. For the racemic mixture this chirality synchronization requires additional surface stabilization. There are unprecedented effects of an applied magnetic field (1 T) on the LC phases, leading to a layer shrinkage by 6-13% for the enantiomer and a layer expansion by 5-8% for the racemate. It is proposed that the magnetic field couples with the π-systems of the almost rod-like molecules. For the racemate this increases the core order, whereas for the enantiomer the reduction of the heliconical twist is considered to provide the major effect. These magnetic field effects could lead to new applications of chiral LC materials at the cross-over between rod-like and bent shapes.
Novel tdp1 inhibitors based on adamantane connected with monoterpene moieties via heterocyclic fragments
Chepanova, Arina A.,Dyrkheeva, Nadezhda S.,Ilina, Ekaterina S.,Korchagina, Dina V.,Lavrik, Olga I.,Mozhaitsev, Evgenii S.,Munkuev, Aldar A.,Reynisson, Jóhannes,Salakhutdinov, Nariman F.,Suslov, Evgeniy V.,Volcho, Konstantin P.,Zakharenko, Alexandra L.,Zakharova, Olga D.
, (2021/06/12)
Tyrosyl-DNA phosphodiesterase 1 (Tdp1) is a promising target for anticancer therapy due to its ability to counter the effects topoisomerase 1 (Top1) poison, such as topotecan, thus, decreasing their efficacy. Compounds containing adamantane and monoterpenoid residues connected via 1,2,4-triazole or 1,3,4-thiadiazole linkers were synthesized and tested against Tdp1. All the derivatives exhibited inhibition at low micromolar or nanomolar concentrations with the most potent inhibitors having IC50 values in the 0.35–0.57 μM range. The cytotoxicity was determined in the HeLa, HCT-116 and SW837 cancer cell lines; moderate CC50 (μM) values were seen from the mid-teens to no effect at 100 μM. Furthermore, citral derivative 20c, α-pinene-derived compounds 20f, 20g and 25c, and the citronellic acid derivative 25b were found to have a sensitizing effect in conjunction with topotecan in the HeLa cervical cancer and colon adenocarcinoma HCT-116 cell lines. The ligands are predicted to bind in the catalytic pocket of Tdp1 and have favorable physicochemical properties for further development as a potential adjunct therapy with Top1 poisons.
New chemical agents based on adamantane-monoterpene conjugates against orthopoxvirus infections
Agafonov, Alexander P.,Bormotov, Nikolay I.,Korchagina, Dina V.,Maksyutov, Rinat A.,Mozhaytsev, Evgenii S.,Salakhutdinov, Nariman F.,Serova, Olga A.,Shishkina, Larisa N.,Suslov, Evgenii V.,Volcho, Konstantin P.,Yarovaya, Olga I.
, p. 1185 - 1195 (2020/11/03)
Currently, the spectrum of agents against orthopoxviruses, in particular smallpox, is very narrow. Despite the fact that smallpox is well controlled, there is, for many reasons, a real threat of epidemics associated with this or a similar virus. In order to search for new low molecular weight orthopoxvirus inhibitors, a series of amides combining adamantane and monoterpene moieties were synthesized using 1- and 2-adamantanecarboxylic acids as well as myrtenic, citronellic and camphorsulfonic acids as acid components. The produced compounds exhibited high activity against the vaccinia virus (an enveloped virus belonging to the poxvirus family), which was combined with low cytotoxicity. Some compounds had a selectivity index higher than that of the reference drug cidofovir; the highest SI = 1123 was exhibited by 1-adamantanecarboxylic acid amide containing the (-)-10-amino-2-pinene moiety. The produced compounds demonstrated inhibitory activity against other orthopoxviruses: cowpox virus (SI = 30-406) and ectromelia virus (mousepox virus, SI = 39-707). This journal is
Environmentally responsible, safe, and chemoselective catalytic hydrogenation of olefins: ppm level Pd catalysis in recyclable water at room temperature
Gallou, Fabrice,Gao, Eugene S.,Lipshutz, Bruce H.,Takale, Balaram S.,Thakore, Ruchita R.
supporting information, p. 6055 - 6061 (2020/10/14)
Textbook catalytic hydrogenations are typically presented as reactions done in organic solvents and oftentimes under varying pressures of hydrogen using specialized equipment. Catalysts new and old are all used under similar conditions that no longer reflect the times. By definition, such reactions are both environmentally irresponsible and dangerous, especially at industrial scales. We now report on a general method for chemoselective and safe hydrogenation of olefins in water using ppm loadings of palladium from commercially available, inexpensive, and recyclable Pd/C, together with hydrogen gas utilized at 1 atmosphere. A variety of alkenes is amenable to reduction, including terminal, highly substituted internal, and variously conjugated arrays. In most cases, only 500 ppm of heterogeneous Pd/C is sufficient, enabled by micellar catalysis used in recyclable water at room temperature. Comparison with several newly introduced catalysts featuring base metals illustrates the superiority of chemistry in water.
Nanostructured Micelle Nanotubes Self-Assembled from Dinucleobase Monomers in Water
Aparicio, Fátima,Casado, Santiago,Chamorro, Paula B.,Chamorro, Raquel,González-Rodríguez, David
supporting information, p. 17091 - 17096 (2020/07/30)
Despite the central importance of aqueous amphiphile assemblies in science and industry, the size and shape of these nano-objects is often difficult to control with accuracy owing to the non-directional nature of the hydrophobic interactions that sustain them. Here, using a bioinspired strategy that consists of programming an amphiphile with shielded directional Watson–Crick hydrogen-bonding functions, its self-assembly in water was guided toward a novel family of chiral micelle nanotubes with partially filled lipophilic pores of about 2 nm in diameter. Moreover, these tailored nanotubes are successfully demonstrated to extract and host molecules that are complementary in size and chemical affinity.
Enantioselective Synthesis and Activity of All Diastereoisomers of (E)-Phytal, a Pheromone Component of the Moroccan Locust, Dociostaurus maroccanus
Guerrero, Angel,Ramos, Victoria Elena,López, Sergio,Alvarez, José María,Domínguez, Aroa,Coca-Abia, María Milagro,Bosch, María Pilar,Quero, Carmen
, p. 72 - 80 (2019/01/15)
The Moroccan locust, Dociostaurus maroccanus (Thunberg, 1815) (Orthoptera: Acrididae), is a polyphagous pest capable of inflicting large losses in agriculture under favorable environmental and climatic conditions. Currently, control of the pest relies solely on the application of conventional insecticides that have negative effects on the environment and human safety. In the search for a more rational, environmentally acceptable approach for locust control, we have previously reported that (Z/E)-phytal (1) is a male-produced candidate sex pheromone of this acridid. This molecule, with two stereogenic centers at C-7 and C-11, has four different diastereomers along with the Z/E stereochemistry of the double bond at C-2. In this paper, we present for the first time the enantioselective synthesis of the four diastereomers of (E)-phytal and their electrophysiological and behavioral activity on males and females. Our results demonstrate that the (R,R)-phytal is the most active diastereomer in both assays, significantly attracting females in a double-choice Y olfactometer, and confirming the previous chromatographic assignment as component of the sex pheromone of the Moroccan locust.
Imine based chiral liquid crystals: Effect of varying the terminal substituent and orientation of ester linking unit
Karanl?k, Gürkan,Ocak, Hale,Bilgin Eran, Belk?z
, p. 567 - 577 (2018/12/02)
New liquid crystalline compounds composed of three-benzene-ring molecular core comprising both the imine and ester linkage units, (S)-3,7-dimethyloctyloxy chiral unit at one of terminals and n-dodecyl/dodecyloxy group as other side chain have been synthesized and characterized to study the effect of varying terminal chains, the orientation of polar ester linking group and the presence of molecular chirality on mesophase properties of imine based calamitic compounds. The liquid crystalline properties of the compounds were investigated by differential scanning calorimetry, optical polarizing microscopy and electro-optic methods. As a result of the strong effect of chirality of (S)-3,7-dimethyloctyloxy chain, all Schiff bases (imines) exhibit enantiotropic chiral smectic C (SmC*), chiral nematic (N*) as well as SmX phase just below the SmC* phase and blue phase (BP) appearing monotropically. The SmC* phase shows ferroelectric switching behaviour with PS values in the range 70–130 nC cm?2. The alteration of the n-alkyl tail with an alkoxy chain gives rise to a significant increase up to 30 °C in mesomorphic transitions. The change in the orientation of polar ester linking group has no effect on the type and sequence of observed LC phase. As compared with (S)-4-(3,7-dimethyloctyloxy)phenol based imine derivatives (7a, 7b), the chiral nematic (N*) mesophase temperature range of (S)-4-(3,7-dimethyloctyloxy)benzoate based compounds (8a, 8b) significantly broadened. Additionally, a decrease on the phase transition temperatures occurred with regardless of introducing n-dodecyl/dodecyloxy group as side chains.
Thermodynamic Characterization of Surface and Solubility of 5-((S)-3,7-Dimethyloctyloxy)-2-[[[4-(octyloxy)phenyl]imino]methyl]phenol Liquid Crystal with Some Solvents
Mutlu Yanic, Serap,Cakar, Fatih,Ocak, Hale,Karaman, Ferdane,Cankurtaran, Ozlem,Bilgin Eran, Belklz
, p. 1007 - 1013 (2019/03/21)
The inverse gas chromatography method was used to obtain dispersive surface energy, surface acidity or basicity constants, mole fraction activity coefficients of the solvents at infinite dilution for a new salicylaldimine based chiral calamitic liquid crystal 5-((S)-3,7-dimethyloctyloxy)-2-[[[4-(octyloxy)phenyl]imino]methyl]phenol (DOPIMP). The dispersive surface energy of DOPIMP was estimated as 41.1 mJ/m2 at 30 °C and decreased with temperature. The specific free energy, enthalpy, and entropy of adsorption of the selected polar solvents on the liquid crystal were determined. The values of adsorption enthalpy were correlated with both donor and acceptor numbers of the solvents to quantify acidic KA and basic KD parameters of the liquid crystal surface. The results indicated that the surface of DOPIMP is basic. The retention diagrams of n-hexane, n-heptane, n-octane, n-nonane, n-decane, undecane, ethyl acetate, n-butyl acetate, iso-butyl acetate, toluene, ethylbenzene, n-propylbenzene, and chlorobenzene on the DOPIMP were plotted as straight lines using the net retention volumes at temperatures between 368.2 and 398.2 K. The values of activity coefficients indicated that DOPIMP was better soluble in long chain alkanes. Negatively signed partial molar Gibbs energies of mixing were obtained at infinite dilution of studied solvents.
