2961-76-4Relevant academic research and scientific papers
Rapid and Simple Access to α-(Hetero)arylacetonitriles from Gem-Difluoroalkenes
Hu, Dandan,Liu, Jiayue,Ren, Hongjun,Song, Jinyu,Zhang, Jun-Qi,Zhu, Guorong
supporting information, p. 786 - 790 (2022/01/28)
A scalable cyanation of gem-difluoroalkenes to (hetero)arylacetonitrile derivatives was developed. This strategy features mild reaction conditions, excellent yields, wide substrate scope, and broad functional group tolerance. Significantly, in this reacti
Development of the sensitizer for generating higher-energy photons under diluted condition via the triplet-triplet annihilation-supported upconversion
Tanaka, Kazuo,Ohashi, Wataru,Inafuku, Kenichi,Shiotsu, Shohei,Chujo, Yoshiki
, (2019/08/26)
It was previously reported that photon upconversion can occur in the solution containing anthracene and the Pt complex of octaethylporphyrin (PtOEP) via the triplet-triplet annihilation process. In this study, by employing the modified Pt complex of the dual anthracene-tethered porphyrin, DA-PtP as a sensitizer, it is demonstrated that shorter-wavelength light can be generated under diluted condition. We synthesized DA-PtP and compared upconversion properties by changing the type of sensitizers. Accordingly, it was shown that the photon upconversion proceeded with the xenon lamp (540 nm) in the presence of DA-PtP. Furthermore, it was found that the emission band in the shorter wavelength light in the near UV region was observed from the solution containing DA-PtP even under diluted condition. From the mechanistic investigation, it was proposed that the anthracene moieties in DA-PtP might inhibit to form agglomeration with the free anthracene. As a result, reabsorption of the higher-energy light generated from upconversion could be suppressed.
Cell-permeable and plasma-stable peptidomimetic inhibitors of the postsynaptic density-95/N-methyl-D-aspartate receptor interaction
Bach, Anders,Eildal, Jonas N. N.,Stuhr-Hansen, Nicolai,Deeskamp, Rasmus,Gottschalk, Marie,Pedersen, S?ren W.,Kristensen, Anders S.,Str?mgaard, Kristian
experimental part, p. 1333 - 1346 (2011/05/07)
The protein-protein interaction between the NMDA receptor and its intracellular scaffolding protein, PSD-95, is a potential target for treating ischemic brain diseases, neuropathic pain, and Alzheimer's disease. We have previously demonstrated that N-alkylated tetrapeptides are potent inhibitors of this interaction, and here, this template is exploited for the development of blood plasma-stable and cell-permeable inhibitors. Initially, we explored both the amino acid sequence of the tetrapeptide and the nature of the N-alkyl groups, which consolidated N-cyclohexylethyl-ETAV (1) as the most potent and selective compound. Next, the amide moieties of N-methylated ETAV were systematically replaced with thioamides, demonstrating that one of three amide bonds could be replaced without compromising the affinity. Subsequent optimization of the N-alkyl groups and evaluation of cell permeability led to identification of N-cyclohexylethyl-ETASV (54) as the most potent, plasma-stable and cell-permeable inhibitor, which is a promising tool in unraveling the therapeutic potential of the PSD-95/NMDA receptor interaction.
Two-step labeling of endogenous enzymatic activities by Diels-Alder ligation
Willems, Lianne I.,Verdoes, Martijn,Florea, Bogdan I.,Van Der Marel, Gijsbert A.,Overkleeft, Herman S.
experimental part, p. 1769 - 1781 (2011/04/18)
A ligation strategy based on the Diels-Alder [4+2] cycloaddition for the two-step activity-based labeling of endogenously expressed enzymes in complex biological samples has been developed. A panel of four diene-derivatized proteasome probes was synthesized, along with a dienophile-functionalized BODIPY(TMR) tag. These probes were applied in a Diels-Alder labeling procedure that enabled us to label active proteasome β-subunits selectively in cellular extracts and in living cells. We were also able to label the activity of cysteine proteases in cell extracts by utilizing a diene-derivatized cathepsin probe. Importantly, the Diels-Alder strategy described here is fully orthogonal with respect to the Staudinger-Bertozzi ligation, as demonstrated by the independent labeling of different proteolytic activities by the two methods in a single experiment.
Synthesis, structure-affinity relationships, and modeling of AMDA analogs at 5-HT2A and H1 receptors: Structural factors contributing to selectivity
Shah, Jitesh R.,Mosier, Philip D.,Roth, Bryan L.,Kellogg, Glen E.,Westkaemper, Richard B.
experimental part, p. 6496 - 6504 (2009/12/06)
Histamine H1 and serotonin 5-HT2A receptors present in the CNS have been implicated in various neuropsychiatric disorders. 9-Aminomethyl-9,10-dihydroanthracene (AMDA), a conformationally constrained diarylalkyl amine derivative, has affinity for both of these receptors. A structure-affinity relationship (SAFIR) study was carried out studying the effects of N-methylation, varying the linker chain length and constraint of the aromatic rings on the binding affinities of the compounds with the 5-HT2A and H1 receptors. Homology modeling of the 5-HT2A and H1 receptors suggests that AMDA and its analogs, the parent of which is a 5-HT2A antagonist, can bind in a fashion analogous to that of classical H1 antagonists whose ring systems are oriented toward the fifth and sixth transmembrane helices. The modeled orientation of the ligands are consistent with the reported site-directed mutagenesis data for 5-HT2A and H1 receptors and provide a potential explanation for the selectivity of ligands acting at both receptors.
Control between TICT and PET using chemical modification of N-phenyl-9-anthracenecarboxamide and its application to a crown ether type chemosensor
Kim, Jeongsik,Morozumi, Tatsuya,Nakamura, Hiroshi
, p. 10735 - 10740 (2008/12/23)
Both twisted intramolecular charge transfer (TICT) and photoinduced electron transfer (PET) relaxation processes of N-phenyl-9-anthrylcarboxamide derivatives can be characterized by modified substitution of the phenyl group. Introduction of a methoxy group to phenyl moiety quenched fluorescence of the anthracene using TICT or PET process, and was not retrieved even using highly viscous media. The introduction of a methylene unit induced fluorescence emissions using a solvent with both viscosity and polarity. This phenomenon demonstrates that the effects of both TICT and PET are involved in this system. Based on these data, we synthesized a novel crown ether derivative 7: its analytical usefulness as a fluorescent chemosensor for alkaline earth metal ions is reported herein.
ORGANIC SEMICONDUCTOR MATERIALS AND PRECURSORS THEREOF
-
Page/Page column 46, (2008/12/07)
The present teachings provide novel organic semiconductor compounds and their soluble precursors, methods for preparing these compounds and precursors, as well as compositions, materials, articles, structures, and devices that incorporate such compounds.
Solvent-dependent effect by carbon dioxide on the photoreactions of (9-anthryl)alkylamines
Horiguchi, Masahiro,Ito, Yoshikatsu
, p. 12286 - 12293 (2008/09/16)
The effect of CO2 on a photoreaction was first studied systematically by using (9-anthryl)alkylamines (APA, AEA, and AMA) as the starting compound. From close scrutiny of the results, the CO2 effect was clearly observed and was well rationalized by the previously reported novel solvent dependence of the amine-CO2 reversible reactions. For instance, the yield of the dimer (h-t from APA or AEA, h-t+h-h from AMA) obtained in MeOH or DMSO was higher under CO2 than under argon and this was ascribed to formation of either ammonium bicarbonate/carbonate in MeOH or carbamic acid in DMSO, which will prevent the nitrogen lone pair from being involved in electron-transfer reactions. In fact, the electron-transfer side reactions producing 1-3 in DMSO were strongly inhibited under CO2. Also, due to formation of noncovalent linkage between the ammonium cation and the carbamate anion in 2-PrOH, the proportion of h-h relative to h-t produced from AMA in 2-PrOH was increased by carrying out the reaction under CO2.
Dynamics of chain exchange between self-assembled diblock copolymer micelles of poly(ethylene oxide)-block-polylactide studied by direct nonradiative excitation energy transfer
Popelka, Stepan,Machova, Lud'ka,Rypacek, Frantisek,Spirkova, Milena,Stepanek, Miroslav,Matejicek, Pavel,Prochazka, Karel
, p. 1811 - 1828 (2007/10/03)
A series of diblock poly(ethylene oxide)-block-polylactide copolymers with fairly narrow distribution of molar masses and compositions was prepared and characterized. The copolymers form multimolecular spherical micelles in 1,4-dioxane-water mixtures. The chain exchange between micelles formed by fluorescence-labeled copolymers was studied by direct nonradiative excitation energy transfer (NRET) fluorescence measurements in water-rich media containing 10 vol.% of 1,4-dioxane. The equilibration rate, i.e., the rate of unimer chain exchange between micelles obeys basically the theoretically predicted scaling relations. It slows down with the length of soluble blocks (a quadratic decrease) and considerably (an exponential decrease) with the length of insoluble chains. Scaling exponents were found lower than those predicted. The study shows that nanoparticle systems based on poly(ethylene oxide)-block-polylactide copolymers with required properties for various biomedical applications can be designed, prepared and their properties can be optimized.
N1-substituent effects in the selective delivery of polyamine conjugates into cells containing active polyamine transporters
Gardner, Richard Andrew,Delcros, Jean-Guy,Konate, Fanta,Breitbeil III, Fred,Martin, Bénédicte,Sigman, Michael,Huang, Min,Phanstiel IV, Otto
, p. 6055 - 6069 (2007/10/03)
Several N1-arylalkylpolyamines containing various aromatic ring systems were synthesized as their respective HCl salts. The N 1-substituents evaluated ranged in size from N1-benzyl, N1-naphthalen-1-ylmethyl, Ns
