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Search for "steady-state fluorescence" in Full Text gives 16 result(s) in Beilstein Journal of Organic Chemistry.
Perspectives on push–pull chromophores derived from click-type [2 + 2] cycloaddition–retroelectrocyclization reactions of electron-rich alkynes and electron-deficient alkenes
- Michio Yamada
Beilstein J. Org. Chem. 2024, 20, 125–154, doi:10.3762/bjoc.20.13
- ) [142]. In these conjugates, the push–pull chromophores and the C60 unit were effectively spatially isolated from each other – a feat achieved through the strategic incorporation of a pyrrolidine ring as the connecting bridge. Thorough examinations via steady-state fluorescence spectroscopy in toluene
Graphical Abstract
Scheme 1: Pathway of the [2 + 2] CA–RE reaction of an electron-rich alkyne with TCNE or TCNQ. EDG = electron-...
Scheme 2: Reaction pathway for DMA-appended acetylene and TCNEO.
Scheme 3: Pathway of the [2 + 2] CA–RE reaction between 1 and DCFs.
Scheme 4: Sequential double [2 + 2] CA–RE reactions between 1 and TCNE.
Scheme 5: Divergent chemical transformation pathways of TCBD 6.
Scheme 6: Synthesis of 12.
Scheme 7: [2 + 2] CA–RE reaction of 1 with 14. TCE = 1,1,2,2-tetrachloroethane.
Scheme 8: Autocatalytic model proposed by Nielsen et al.
Scheme 9: Synthesis of anthracene-embedded TCBD compound 19.
Scheme 10: Sequence of the [2 + 2] CA–RE reaction between dibenzo-fused cyclooctyne or cyclooctadiyne and TCNE...
Scheme 11: [2 + 2] CA–RE reaction between the CPP derivatives and TCNE. THF = tetrahydrofuran.
Scheme 12: [2 + 2] CA–RE reaction between ethynylfullerenes 31 and TCNE and subsequent thermal rearrangement.
Scheme 13: Pathway of the [2 + 2] CA–RE reaction between TCNE and 34, followed by additional skeletal transfor...
Scheme 14: Synthesis scheme for heterocycle 38 from the reaction between TCNE and 1 in water and a surfactant.
Scheme 15: Synthesis scheme of the CDA product 41.
Scheme 16: Synthesis of rotaxanes 44 and 46 via the [2 + 2] CA–RE reaction.
Scheme 17: Synthesis of a CuI bisphenanthroline-based rotaxane 50.
Figure 1: Structures of the chiral push–pull chromophores 51–56.
Figure 2: Structures of the axially chiral TCBD 57 and DCNQ 58 bearing a C60 core.
Figure 3: Structures of the axially chiral SubPc–TCBD–aniline conjugates 59 and 60 and the subporphyrin–TCBD–...
Figure 4: Structures of 63 and the TCBD 64.
Figure 5: Structures of the fluorophore-containing TCBDs 65–67.
Figure 6: Structures of the fluorophore-containing TCBDs 68–72.
Figure 7: Structures of the urea-containing TCBDs 73–75.
Figure 8: Structures of the fullerene–TCBD and DCNQ conjugates 76–79 and their reference compounds 80–83.
Figure 9: Structures of the ZnPc–TCBD–aniline conjugates 84 and 85.
Figure 10: Structures of the ZnP–PCBD and TCBD conjugates 86–88.
Figure 11: Structures of the porphyrin-based donor–acceptor conjugates (89–104).
Figure 12: Structures of the porphyrin–PTZ or DMA conjugates 105–112.
Figure 13: Structures of the BODIPY–Acceptor–TPA or PTZ conjugates 113–116.
Figure 14: Structures of the corrole–TCBD conjugates 117 and 118.
Figure 15: Structure of the dendritic TCBD 119.
Figure 16: Structures of the TCBDs 120–126.
Figure 17: Structures of the precursor 127 and TCBDs 128–130.
Figure 18: Structures of 131–134 utilized for BHJ OSCs.
Photoredox catalysis harvesting multiple photon or electrochemical energies
- Mattia Lepori,
- Simon Schmid and
- Joshua P. Barham
Beilstein J. Org. Chem. 2023, 19, 1055–1145, doi:10.3762/bjoc.19.81
- a two-photon process. DBU was found to quench the steady-state fluorescence of *PC1 with a quenching rate constant two orders of magnitude smaller than the diffusion rate constant in DMSO at 298 K and one order of magnitude greater under the borylation reaction conditions (i.e., 0.20 M DBU) than the
Graphical Abstract
Figure 1: Oxidative and reductive activations of organic compounds harvesting photoredox catalysis.
Figure 2: General catalytic cycles of radical ion conPET (left) and radical ion e-PRC (right).
Figure 3: “Beginner’s guide”: comparison between advantages, capacities, and prospectives of conPET and PEC.
Figure 4: A) conPET reductive dehalogenation of aryl halides with PDI. B) Reductive C–H arylation with pyrrol...
Figure 5: A) Chromoselective mono- and disubstitution or polybrominated pyrimidines with pyrroles. B) Sequent...
Figure 6: A) Synthesis of pyrrolo[1,2-a]quinolines. B) Synthesis of ullazines.
Figure 7: A) Reductive phosphorylation of aryl halides via conPET. B) Selected examples from the substrate sc...
Figure 8: A) Reductive dehalogenation of aryl halides via conPET and selected examples from the substrate sco...
Figure 9: A) Reductive C–H arylation of aryl halides via conPET (top) and selected examples from the substrat...
Figure 10: A) Reductive hydrodehalogenation of aryl halides with Mes-Acr-BF4. B) Selected examples from the su...
Figure 11: A) Reductive hydrodechlorination of aryl chlorides with 4-DPAIPN. B) Proposed formation of CO2•−. C...
Figure 12: A) Reductive conPET borylation with 3CzEPAIPN (top) and selected examples from the substrate scope ...
Figure 13: Scale-up of conPET phosphorylation with 3CzEPAIPN.
Figure 14: A) Borylation of 1d. B) Characteristics and structure of PC1 with green and red parts showing the l...
Figure 15: A) Reductive C–H arylation scope with polysulfide conPET (top) and selected examples from the subst...
Figure 16: Scale-up of A) C–H arylation and B) dehaloborylation with polysulfide photocatalysis in continuous-...
Figure 17: A) Formation of [Ir1]0 and [Ir2]0 upon PET between [Ir1]+ and Et3N. B) Mechanism of multi-photon ta...
Figure 18: A) Reductive hydrodehalogenation of aryl halides via multi-photon tandem photocatalysis. B) Selecte...
Figure 19: A) Carbonylative amidation of aryl halides in continuous flow. B) Selected examples from the substr...
Figure 20: A) General scheme for reductive (RQ) and oxidative quenching (OQ) protocols using [FeIII(btz)3](PF6)...
Figure 21: A) Carbonylative amidation of alkyl iodides with [IrIII(ppy)2(dtbbpy)]PF6. B) Selected examples fro...
Figure 22: A) Carboxylative C–N bond cleavage in cyclic amines. B) Selected examples from the substrate scope....
Figure 23: A) Formal reduction of alkenes to alkanes via transfer hydrogenation. B) Selected examples from the...
Figure 24: A) Birch-type reduction of benzenes with PMP-BPI. B) Selected examples from the substrate scope (sc...
Figure 25: Proposed mechanism of the OH− mediated conPET Birch-type reduction of benzene via generation of sol...
Figure 26: Reductive detosylation of N-tosylated amides with Mes-Acr-BF4. B) Selected examples from the substr...
Figure 27: A) Reductive detosylation of N-tosyl amides by dual PRC. B) Selected examples from the substrate sc...
Figure 28: A) Mechanism of the dual PRC based on PET between [Cu(dap)2]+ and DCA. B) Mechanism of the dual PRC...
Figure 29: A) N–O bond cleavage in Weinreb amides with anthracene. B) N–O bond cleavage in Weinreb amides rely...
Figure 30: A) Pentafluorosulfanylation and fluoride elimination. B) Mechanism of the pentafluorosulfanylation ...
Figure 31: A) α-Alkoxypentafluorosulfanylation (top) and selected examples from the substrate scope (bottom). ...
Figure 32: A) Oxidative amination of arenes with azoles catalyzed by N-Ph PTZ. B) Selected examples from the s...
Figure 33: A) C(sp3)–H bond activation by HAT via chloride oxidation by *N-Ph PTZ•+. B) Proposed mechanism for...
Figure 34: A) Recycling e-PRC C–H azolation of electron-rich arenes with pyrazoles using Mes-Acr+ as a photoca...
Figure 35: A) Radical ion e-PRC direct oxidation of unactivated arenes using TAC+ as an electro-activated phot...
Figure 36: A) Radical ion e-PRC direct oxidation of unactivated arenes using TPA as an electro-activated photo...
Figure 37: Proposed mechanism (top) and mode of preassembly (bottom).
Figure 38: A) Possible preassemblies of reactive (left) vs unreactive (right) arenes. B) Calculated spin densi...
Figure 39: A) Recycling e-PRC C(sp2 )–H acetoxylation of arenes using DDQ as a photocatalyst. B) Proposed cata...
Figure 40: Gram scale hydroxylation of benzene in a recirculated flow setup.
Figure 41: A) Radical ion e-PRC vicinal diamination of alkylarenes using TAC+ as an electro-activated photocat...
Figure 42: A) Sequential oxygenation of multiple adjacent C–H bonds under radical ion e-PRC using TAC+ as an e...
Figure 43: A) Enantioselective recycling e-PRC cyanation of benzylic C–H bonds using ADQS as photocatalyst. B)...
Figure 44: Proposed tandem mechanism by Xu and co-workers.
Figure 45: A) Enantioselective recycling e-PRC decarboxylative cyanation using Cu(acac)2, Ce(OTf)3 and a box l...
Figure 46: A) Enantioselective recycling e-PRC benzylic cyanation using Cu(MeCN)4BF4, box ligand and anthraqui...
Figure 47: A) Radical ion e-PRC acetoxyhydroxylation of aryl olefins using TAC+ as an electro-activated photoc...
Figure 48: Selected examples from the substrate scope.
Figure 49: Photoelectrochemical acetoxyhydroxylation in a recirculated flow setup.
Figure 50: A) Radical ion e-PRC aminooxygenation of aryl olefins using TAC+ as an electro-activated photocatal...
Figure 51: A) Recycling e-PRC C–H alkylation of heteroarenes with organic trifluoroborates using Mes-Acr+ as p...
Figure 52: A) Recycling e-PRC decarboxylative C–H alkylation of heteroarenes using CeCl3·7H2O as catalyst. B) ...
Figure 53: A) Recycling e-PRC decarboxylative C–H alkylation of heteroarenes using Fe(NH4)2(SO4)2·6H2O as cata...
Figure 54: A) Recycling e-PRC C–H alkylation of heteroarenes with alkyl oxalates and 4CzIPN as photocatalyst. ...
Figure 55: A) Recycling e-PRC decarboxylative C–H carbamoylation of heteroarenes using 4CzIPN as photocatalyst...
Figure 56: A) Photoelectrochemical HAT-mediated hydrocarbon activation via the chlorine radical. B) Proposed m...
Figure 57: A) Selected examples from the substrate scope. B) Gram and decagram scale semi-continuous flow PEC ...
Figure 58: A) Photoelectrochemical HAT-mediated dehydrogenative coupling of benzothiazoles with aliphatic C–H ...
Figure 59: A) Photoelectrochemical HAT activation of ethers using electro-activated TAC+ as photocatalyst. B) ...
Figure 60: Selected examples from the substrate scope.
Figure 61: A) Photoelectrochemical HAT-mediated synthesis of alkylated benzimidazo-fused isoquinolinones using...
Figure 62: A) Decoupled photoelectrochemical cerium-catalyzed oxydichlorination of alkynes using CeCl3 as cata...
Figure 63: Proposed decoupled photoelectrochemical mechanism.
Figure 64: A) Decoupled photoelectrochemical ring-opening bromination of tertiary cycloalkanols using MgBr2 as...
Figure 65: A) Recycling e-PRC ring-opening functionalization of cycloalkanols using CeCl3 as catalyst. B) Prop...
Figure 66: Selected examples from the substrate scope of the PEC ring-opening functionalization.
Figure 67: A) Radical ion e-PRC reduction of chloro- and bromoarenes using DCA as catalyst and various accepto...
Figure 68: A) Screening of different phthalimide derivatives as catalyst for the e-PRC reduction of aryl halid...
Figure 69: Screening of different organic catalysts for the e-PRC reduction of trialkylanilium salts.
Figure 70: A) e-PRC reduction of phosphonated phenols and anilinium salts. B) Selected examples from the subst...
Figure 71: A) ConPET and e-PRC reduction of 4-bromobenzonitrile using a naphthalene diimide (NDI) precatalyst ...
Figure 72: A) Radical ion e-PRC reduction of phosphinated aliphatic alcohols with n-BuO-NpMI as catalyst. B) C...
Figure 73: Selected examples from the substrate scope.
Figure 74: A) Recycling e-PRC reductive dimerization of benzylic chlorides using a [Cu2] catalyst. B) Proposed...
Figure 75: A) Decoupled photoelectrochemical C–H alkylation of heteroarenes through deamination of Katritzky s...
Figure 76: Proposed mechanism by Chen and co-workers.
Photophysical, photostability, and ROS generation properties of new trifluoromethylated quinoline-phenol Schiff bases
- Inaiá O. Rocha,
- Yuri G. Kappenberg,
- Wilian C. Rosa,
- Clarissa P. Frizzo,
- Nilo Zanatta,
- Marcos A. P. Martins,
- Isadora Tisoco,
- Bernardo A. Iglesias and
- Helio G. Bonacorso
Beilstein J. Org. Chem. 2021, 17, 2799–2811, doi:10.3762/bjoc.17.191
- coefficients of the derivatives studied here. All absorption spectra are listed in Supporting Information File 1 (Figures S2–S7). The steady-state fluorescence emission spectra of the Schiff base compounds from their absorption in the UV–vis region was carried out. Derivatives 3aa–fa and 3bb–be were analyzed
- showing coplanarity of the same system. Normalized absorption spectra in the UV–vis region of compounds (a) 3ea and (b) 3be in CHCl3, MeOH or DMSO solution, respectively ([ ] = 1.50 × 10−5 M). Normalized steady-state fluorescence emission spectra of compound 3aa (R = Ph, R1 = H) in CHCl3 (black solid line
- ), DMSO (red solid line) and MeOH (light green solid line) solutions ([ ] = 1.50 × 10−5 M). Comparative normalized steady-state fluorescence emission spectra of compounds 3bb and 3be in the three studied solvents ([ ] = 1.50 × 10−5 M). Photostability (%) plots of derivatives 3aa–fa and 3bb–be in DMSO
Graphical Abstract
Figure 1: Examples of structures and properties of Schiff bases of interest in the present study.
Scheme 1: General view for the present study.
Scheme 2: Synthesis of ((trifluoromethyl)quinolinyl)phenol Schiff bases 3aa–fa.
Scheme 3: Synthesis of trifluoromethylated quinolinyl-phenol Schiff bases 3bb–be.
Figure 2: ORTEP diagram of the crystal structure of (E)-2-(((2-phenyl-4-(trifluoromethyl)quinolin-6-yl)imino)...
Figure 3: Normalized absorption spectra in the UV–vis region of compounds (a) 3ea and (b) 3be in CHCl3, MeOH ...
Figure 4: Normalized steady-state fluorescence emission spectra of compound 3aa (R = Ph, R1 = H) in CHCl3 (bl...
Figure 5: Comparative normalized steady-state fluorescence emission spectra of compounds 3bb and 3be in the t...
Figure 6: Photostability (%) plots of derivatives 3aa–fa and 3bb–be in DMSO solution after irradiation with w...
Figure 7: DPBF photooxidation assays by red-light irradiation with diode laser (λ = 660 nm) in the presence o...
The B & B approach: Ball-milling conjugation of dextran with phenylboronic acid (PBA)-functionalized BODIPY
- Patrizia Andreozzi,
- Lorenza Tamberi,
- Elisamaria Tasca,
- Gina Elena Giacomazzo,
- Marta Martinez,
- Mirko Severi,
- Marco Marradi,
- Stefano Cicchi,
- Sergio Moya,
- Giacomo Biagiotti and
- Barbara Richichi
Beilstein J. Org. Chem. 2020, 16, 2272–2281, doi:10.3762/bjoc.16.188
- . The stock solution was diluted 1:2 in ultra-HPLC water, and 1 μL of the solution was deposited on the top of the TEM grid and left dried at room temperature. Steady state fluorescence measurements were performed on a Fluorolog®-3 spectrofluorometer (Horiba-Jobin Yvon) using 1.0 × 1.0 cm quartz cuvette
Graphical Abstract
Figure 1: Structure of PBA-BODIPY (1) and schematic representation of dextran (Dex) and PBA-BODIPY conjugated...
Scheme 1: Schematic representation of dextran/PBA-BODIPY bioconjugations in: A. conventional solution-based c...
Figure 2: A) Amount of recovered PBA-BODIPY (1, i.e., nonreacted 1) in the mixtures DMSO/EtOH and in the seri...
Figure 3: A) UV–vis absorption and B) fluorescence emission spectra (λexc = 380 nm) of the BODIPY-dextran con...
Figure 4: A) Hydrodynamic diameter of (nm) conjugate Dex-1b (at 1 mg/mL in H2O, black curve) and PBS (red cur...
Figure 5: Fluorescence emission spectra of pyrene (4.4 × 10−8 M) in water and in a water solution in the pres...
Naphthalene diimide–amino acid conjugates as novel fluorimetric and CD probes for differentiation between ds-DNA and ds-RNA
- Annike Weißenstein,
- Myroslav O. Vysotsky,
- Ivo Piantanida and
- Frank Würthner
Beilstein J. Org. Chem. 2020, 16, 2032–2045, doi:10.3762/bjoc.16.170
- (cacodylate buffer, pH 5.0, λex = 470 nm): λmax [nm] = 573; Φfl = 0.32. Spectrophotometric studies The UV–vis spectra were recorded on a Varian Cary 100 Bio spectrophotometer or on a Jasco V670/770 spectrometer, steady state fluorescence spectra were measured on a PTI QM4/2003 or Varian Eclipse
Graphical Abstract
Figure 1: Structures of investigated compounds stressing steric differences in linker length attached to the ...
Scheme 1: Synthesis of water-soluble naphthalene diimides 3a,b, and 5.
Figure 2: UV–vis absorption (solid line) and fluorescence spectra (dashed line) of NDI 3a,b, and 5 (c = 4.5 ×...
Figure 3: Calculations for Cl-NDI-NMe model compound (at the B3LYP/6-31+G** level of theory) in water (PCM). ...
Figure 4: (a) Melting curve of poly(dA-dT)2 alone and after the addition of NDI 3a,b, and 5 (r = 0.3 ([NDI]/[...
Figure 5: Changes in fluorescence intensity (spectra are normalized) of (a) 3a (c = 1.0 × 10−6 M), (b) 3b (c ...
Figure 6: Calorimetric titration of a poly(dG-dC)2 solution in sodium cacodylate buffer (pH 5.0) at 298 K wit...
Figure 7: CD titration of poly(dG-dC)2 (c = 2.0 × 10−5 M) with (a) 3a, (b) 3b, and (c) 5 with increasing mola...
Figure 8: Schematic representation of the alignment of the intercalating 3a (left) and 3b (right) between the...
Ultrafast processes triggered by one- and two-photon excitation of a photochromic and luminescent hydrazone
- Alessandro Iagatti,
- Baihao Shao,
- Alberto Credi,
- Barbara Ventura,
- Ivan Aprahamian and
- Mariangela Di Donato
Beilstein J. Org. Chem. 2019, 15, 2438–2446, doi:10.3762/bjoc.15.236
- distribution of the excited-state decays reveals the presence of a short component in the blue region of the spectrum (440–460 nm) which is not present in the remaining emission region (500–600 nm). A weak emission in this region is also observed in the steady-state fluorescence spectra obtained upon
- -state fluorescence of the E-isomers in most solvents. Transient absorption spectroscopy measurements, repeated in different solvents, allowed us to estimate the timescale of the Z/E isomerization process, which is about 0.5 ps in both toluene and acetonitrile, thus showing a negligible dependence on the
- lifetime of the Z-form, which strongly emits in the 500–520 nm spectral range. A fast component (1.3 ps in toluene) was also observed at shorter wavelengths and attributed to the E-isomer. The very short lifetime of this component accounts for the low emission quantum yield or even the absence of steady
Graphical Abstract
Figure 1: a) The photoinduced Z/E isomerization of hydrazone 1, and accompanied changes in b) UV–vis absorpti...
Figure 2: Fluorescence decays (dots) in the 500–520 nm spectral region (emission range of the Z-isomer) for 1...
Figure 3: Fluorescence decays (dots) in the 500–520 nm spectral region (red; induced Z-emission), and in the ...
Figure 4: a) Transient absorption data recorded for hydrazone 1 in toluene upon excitation at 400 nm; b) EADS...
Figure 5: EADS obtained by global fit of the transient data recorded in a) acetonitrile and b) methanol upon ...
Figure 6: Kinetic traces recorded at the maximum of the excited state absorption band in toluene, acetonitril...
Figure 7: a) Transient absorption spectra measured for hydrazone 1 in toluene upon excitation at 785 nm. b) C...
Complexation of a guanidinium-modified calixarene with diverse dyes and investigation of the corresponding photophysical response
- Yu-Ying Wang,
- Yong Kong,
- Zhe Zheng,
- Wen-Chao Geng,
- Zi-Yi Zhao,
- Hongwei Sun and
- Dong-Sheng Guo
Beilstein J. Org. Chem. 2019, 15, 1394–1406, doi:10.3762/bjoc.15.139
- measured in HEPES buffer (10 mM, pH 7.4) at 25 °C. Instruments Steady-state fluorescence measurements were recorded in a conventional quartz cuvette (light path 10 mm) on a Cary Eclipse equipped with a Cary single-cuvette peltier accessory. UV–vis spectra were recorded in a quartz cuvette (light path 10 mm
Graphical Abstract
Scheme 1: (a) Schematic illustration of IDA. The addition of an analyte competitor leads to switch-on or swit...
Scheme 2: (a) The chemical structure of GC5A and schematic illustration of the binding between the luminescen...
Figure 1: Direct fluorescence titrations (λex = 350 nm) of 2,6-TNS (1.0 μM) (a) and 1,8-ANS (1.0 μM) (c) with...
Figure 2: (a) Direct fluorescence titration (λex = 327 nm) of P-TPE (1.0 μM) with GC5A in HEPES buffer (10 mM...
Figure 3: (a) Direct fluorescence titration (λex = 371 nm) of TPS (1.0 μM) with GC5A in HEPES buffer (10 mM, ...
Figure 4: (a) Direct fluorescence titration (λex = 465 nm) of Ru(dcbpy)3 (1.0 μM) with GC5A. (b) Direct absor...
Pyrene–nucleobase conjugates: synthesis, oligonucleotide binding and confocal bioimaging studies
- Artur Jabłoński,
- Yannic Fritz,
- Hans-Achim Wagenknecht,
- Rafał Czerwieniec,
- Tytus Bernaś,
- Damian Trzybiński,
- Krzysztof Woźniak and
- Konrad Kowalski
Beilstein J. Org. Chem. 2017, 13, 2521–2534, doi:10.3762/bjoc.13.249
- ) solutions in ethanol with a Horiba Jobin Yvon Fluorolog 3 steady-state fluorescence spectrometer. For decay time measurements a PicoQuant LDH-P-C-375 pulsed diode laser (λexc = 372 nm, pulse width 100 ps) was applied as the excitation source. The emission signal was detected with a cooled photomultiplier
Graphical Abstract
Figure 1: Examples of pyrene derivatives with relevance to nucleic acid chemistry and structures of pyrenyl–n...
Scheme 1: Synthesis of pyrene–nucleobase conjugates 2–5.
Figure 2: ORTEP diagram of 2 at 50% probability level. The hydrogen and halogen bonds are represented by dash...
Figure 3: Intermolecular hydrogen bonding (N22–H22···O27 distance = 2.882(2) Å) and halogen bonding (C30–Cl31...
Figure 4: UV–vis absorption and fluorescence spectra of pyrene–adenines 5 (a) and 3 (b) in diluted (c ≈ 10−5 ...
Figure 5: Absorption changes during titration of 2 and 4 (λ = 344 nm) in the presence of (dA)10, and 3 and 5 ...
Figure 6: Cellular distribution of 4 in living HeLa cells. (A) Fluorescence of 4 (green). (B) Fluorescence of...
Figure 7: Cellular distribution of 5 in living HeLa cells. (A) Fluorescence of 5 (green). Arrows are marking ...
Interactions between cyclodextrins and cellular components: Towards greener medical applications?
- Loïc Leclercq
Beilstein J. Org. Chem. 2016, 12, 2644–2662, doi:10.3762/bjoc.12.261
- steady-state fluorescence spectroscopy, the estimated constants of free Tyr increased in the order α-CD < β-CD. As in the previous study, the stability constants of pentapeptides containing Tyr with β-CD were higher than that of Tyr itself (48, 224, and 123 M–1 for free Try, YIGSR, and YGGFL
Graphical Abstract
Scheme 1: Structure and conventional representation of native CDs.
Scheme 2: Proposed mechanism for morphological changes in erythrocytes induced by methylated CDs.
Scheme 3: Proposed mechanism for the conformational change of egg white lysozyme with temperature elevating i...
Scheme 4: Sugar hydrophobicity scale according to Janado and Yano and correlation with the binding constant v...
Scheme 5: Principle of chemically switched DNA intercalators based on anthryl(alkylamino)-β-CD/1-adamantanol ...
Scheme 6: Normal (left) and diseased artery (right).
Scheme 7: Kinetics of [DiC10] insertion into the viral envelope without (left) or with γ-CD (right). Note tha...
Synthesis and surface grafting of a β-cyclodextrin dimer facilitating cooperative inclusion of 2,6-ANS
- Lars W. Städe,
- Thorbjørn T. Nielsen,
- Laurent Duroux,
- Reinhard Wimmer,
- Kyoko Shimizu and
- Kim L. Larsen
Beilstein J. Org. Chem. 2015, 11, 514–523, doi:10.3762/bjoc.11.58
- negligible. Inclusion complex with free β-CD dimer in solution Host–guest interactions with the fluorescent probe 2,6-ANS were evaluated for the β-CD dimer by steady-state fluorescence spectroscopy and compared to that of the parent β-CD and 2,6-ANS. In water, 2,6-ANS displays only weak fluorescence
- in Ka reveals a notably stronger binding of 2,6-ANS to the β-CD dimer, as compared to the parent β-CD. Further, the goodness of fit confirms the 1:1 stoichiometry (R2 = 0.998). The steady-state fluorescence titration experiment thereby appears to confirm the suggested binding mode, that is, the
- and 2,6-ANS. (a) Steady-state fluorescence emission spectra of 50 µM 2,6-ANS in PBS (solid grey, smoothed), in the presence of 4 mM β-CD (black dotted) and in the presence of 2 mM β-CD dimer (plain black) and (b) the corresponding normalized spectra. The emission maxima are in the listed order 475
Graphical Abstract
Scheme 1: Synthetic route for the synthesis of the β-CD dimer with a free alkyne, allowing for subsequent sur...
Figure 1: MS spectra (2440–2500 Da) of the purified β-CD dimer.
Figure 2: Structure of fluorescent guest molecule, 2,6-ANS, used to probe host–guest interaction and two deri...
Figure 3: Illustration of potential 1:1 inclusion complexes of the β-CD dimer and 2,6-ANS.
Figure 4: (a) Steady-state fluorescence emission spectra of 50 µM 2,6-ANS in PBS (solid grey, smoothed), in t...
Figure 5: Region of interest of a ROESY (250 ms mixing time) showing cross peaks between the β-CD-dimer and 2...
Figure 6: Steady-state fluorescence titration of 2,6-ANS with β-CD dimer and parent β-CD in solution. 2,6-ANS...
Scheme 2: Synthetic route for the activation of silicon dioxide surfaces and the grafting of the β-CD dimer t...
Figure 7: (a) Steady-state TIRF emission spectra of 1 mM 2,6-ANS in PBS, recorded on a bare quartz slide (sol...
Formation of nanoparticles by cooperative inclusion between (S)-camptothecin-modified dextrans and β-cyclodextrin polymers
- Thorbjørn Terndrup Nielsen,
- Catherine Amiel,
- Laurent Duroux,
- Kim Lambertsen Larsen,
- Lars Wagner Städe,
- Reinhard Wimmer and
- Véronique Wintgens
Beilstein J. Org. Chem. 2015, 11, 147–154, doi:10.3762/bjoc.11.14
- . For each sample an average of 5 scans was recorded, with excitation and emission slits set to 5 nm and a PMT detector voltage of 400 V. The excitation wavelength was set at 350 nm and wave scans recorded between 360 nm and 600 nm. For the estimation of association constants by steady-state
- fluorescence spectroscopy, stock solutions of D70GPCPT and D10GPCPT (45 µM CPT) and D70HPβ-CD (2 mM) were prepared in MQ water. Titration was performed by diluting the D70HPβ-CD stock solution to its final concentration (0–2 mM) with the corresponding CPT polymer, while ensuring a constant concentration of CPT
Graphical Abstract
Scheme 1: Reaction scheme for synthesis of azide-modified (S)-camptothecin.
Scheme 2: Cu(I)-catalyzed grafting of azide-modified (S)-camptothecin onto alkyne-modified dextran.
Figure 1: Titration of a) D70GP-CPT2 and b) D10GP-CPT1 by D70HPβ-CD at 298 K showing heat flow as a function ...
Figure 2: Fluorescence emission spectra of a) D70GPCPT and b) D10GPCPT recorded at different concentrations (...
Synthesis, characterization and DNA interaction studies of new triptycene derivatives
- Sourav Chakraborty,
- Snehasish Mondal,
- Rina Kumari,
- Sourav Bhowmick,
- Prolay Das and
- Neeladri Das
Beilstein J. Org. Chem. 2014, 10, 1290–1298, doi:10.3762/bjoc.10.130
- showed some displacement of the intercalated EtBr, as evident from the steady-state fluorescence data (Supporting Information File 1, Figure S2). This indicates that the mode of interaction of the compounds with DNA may not be intercalation except for the triptycene derivatives 5 and 6. No noticeable
Graphical Abstract
Scheme 1: Synthesis of TETs 1 and 2 and TATs 3 and 4.
Scheme 2: Synthesis of triptycenetripropiolic acid (TPA) 5 and 6.
Scheme 3: Synthesis of triphosphinotriptycenes (TPT) 7 and 8.
Figure 1: Nuclease activities of the triptycene derivatives 1–8. Agarose gel (top) shows results of the incub...
Figure 2: Effect of triptycene derivatives on the restriction endonuclease activity of HindIII and BamHI enzy...
Figure 3: (A) Oligomer duplex sequence that was used to study the effect of triptycene derivatives on the aba...
Figure 4: UV–vis spectra showing the hyperchromic effect after addition of ctDNA (20 μM) to 5 and 6 (80 μM).
Figure 5: UV–vis absorption spectra of (A) 2,6,14-trisubstituted triptycene derivatives 1, 3, 5 and 7 in DMSO...
Tailoring of organic dyes with oxidoreductive compounds to obtain photocyclic radical generator systems exhibiting photocatalytic behavior
- Christian Ley,
- Julien Christmann,
- Ahmad Ibrahim,
- Luciano H. Di Stefano and
- Xavier Allonas
Beilstein J. Org. Chem. 2014, 10, 936–947, doi:10.3762/bjoc.10.92
- Time-Correlated Single-Photon Counting (TCSPC) accessory was used to measure the steady-state fluorescence spectra and singlet excited state lifetimes. NanoLEDs were used as pulsed excitation source leading to a time resolution of around 200 ps. The measurements were performed in acetonitrile solutions
Graphical Abstract
Scheme 1: Chemical structures of RB, EDB and TA.
Scheme 2: Type II PIS mechanisms. PS: photosensitizer; 1,3PS*: singlet and triplet PS excited states; PS•+: o...
Figure 1: Evolution of RB concentration as a function of irradiation time (λ = 532 nm, 9 mW·cm−3); insert: ab...
Scheme 3: Photocatalytic behavior occurring in three component PIS. PS: photosensitizer; 1,3PS*: singlet and ...
Figure 2: Evolution of [RB](t) in the photocyclic system RB/TA/EDB as a function of irradiation time (λ = 532...
Scheme 4:
Thermodynamics of an oxidative three components PCIS, a) ground state reaction (![[Graphic 1]](/bjoc/content/inline/1860-5397-10-92-i10.png?max-width=637&scale=1.18182)
), b) excited state...
Scheme 5: General photocatalytic cycle occurring in three components photocyclic systems. Two cycles are in c...
Figure 3: Mechanistic description of photocyclic system involved in the RB/TA/EDB system. The rate constants ...
Figure 4: Evolution of RB, RB•+, TA, and TA•− concentration with time for RB/TA system.
Figure 5: Evolution of RB, TA and EDB concentrations in the photocyclic system. The logarithm of oxidative an...
Figure 6: Evolution of radical concentrations TA•− and EDB•+ together with [RB] in photocatalytic system.
Interaction of cyclodextrins with pyrene-modified polyacrylamide in a mixed solvent of water and dimethyl sulfoxide as studied by steady-state fluorescence
- Akihito Hashidzume,
- Yongtai Zheng and
- Akira Harada
Beilstein J. Org. Chem. 2012, 8, 1312–1317, doi:10.3762/bjoc.8.150
- β-CD and γ-CD with Py-modified polyacrylamide (pAAmPy, Scheme 1) was investigated in the water/DMSO mixed solvent of varying composition by steady-state fluorescence to elucidate the mechanism of the selectivity switching. Results Figure 1a demonstrates the steady-state fluorescence spectra measured
- of the excimer fluorescence increases whereas that of the monomer fluorescence decreases with increasing [CD]0, indicating that γ-CD forms inclusion complexes with dimeric Py residues, and monomeric Py residues further associate to form the dimers. Using the steady-state fluorescence spectra, I480
- with Py-modified water-soluble polymers, including the formation of the dynamic excimer, requires not only steady-state fluorescence measurements but also time-resolved fluorescence measurements [38][39][40][41][42][43]. In this study, however, equilibrium constants are roughly estimated by analyzing
Graphical Abstract
Scheme 1: Structure of pAAmPy.
Figure 1: Steady-state fluorescence spectra for 0.04 g L−1 pAAmPy at varying xDMSO from 0 to 1 with excitatio...
Figure 2: Steady-state fluorescence spectra for 0.04 g L−1 pAAmPy with excitation at 335 nm in the presence o...
Figure 3: I480/I376 as a function of [CD]0 for β-CD/pAAmPy (a) and γ-CD/pAAmPy (b) at different xDMSO.
Scheme 2: Simplified equilibria of CDs/pAAmPy systems.
Figure 4: KPy, Kβ, and Kγ as a function of xDMSO.
Molecular recognition of organic ammonium ions in solution using synthetic receptors
- Andreas Späth and
- Burkhard König
Beilstein J. Org. Chem. 2010, 6, No. 32, doi:10.3762/bjoc.6.32
Graphical Abstract
Figure 1: Biologically important amines and quaternary ammonium salts: histamine (1), dopamine (2) and acetyl...
Figure 2: Crown ether 18-crown-6.
Figure 3: Conformations of 18-crown-6 (4) in solvents of different polarity.
Figure 4: Binding topologies of the ammonium ion depending on the crown ring size.
Figure 5: A “pseudorotaxane” structure consisting of 24-crown-8 and a secondary ammonium ion (5); R = Ph.
Figure 6: Typical examples of azacrown ethers, cryptands and related aza macrocycles.
Figure 7: Binding of ammonium to azacrown ethers and cryptands [111-113].
Figure 8: A 19-crown-6-ether with decalino blocking groups (11) and a thiazole-dibenzo-18-crown-6-ether (12).
Figure 9: 1,3-Bis(6-oxopyridazin-1-yl)propane derivatives 13 and 14 by Campayo et al.
Figure 10: Fluorescent azacrown-PET-sensors based on coumarin.
Figure 11: Two different pyridino-cryptands (17 and 18) compared to a pyridino-crown (19); chiral ammonium ion...
Figure 12: Pyridino-18-crown-6 ligand (21), a similar acridino-18-crown-6 ligand (22) and a structurally relat...
Figure 13: Ciral pyridine-azacrown ether receptors 24.
Figure 14: Chiral 15-crown-5 receptors 26 and an analogue 18-crown-6 ligand 27 derived from amino alcohols.
Figure 15: C2-symmetric chiral 18-crown-6 amino alcohol derivatives 28 and related macrocycles.
Figure 16: Macrocycles with diamide-diester groups (30).
Figure 17: C2-symmetric chiral aza-18-crown-6 ethers (31) with phenethylamine residues.
Figure 18: Chiral C-pivot p-methoxy-phenoxy-lariat ethers.
Figure 19: Chiral lariat crown ether 34.
Figure 20: Sucrose-based chiral crown ether receptors 36.
Figure 21: Permethylated fructooligosaccharide 37 showing induced-fit chiral recognition.
Figure 22: Biphenanthryl-18-crown-6 derivative 38.
Figure 23: Chiral lariat crown ethers derived from binol by Fuji et al.
Figure 24: Chiral phenolic crown ether 41 with “aryl chiral barriers” and guest amines.
Figure 25: Chiral bis-crown receptor 43 with a meso-ternaphthalene backbone.
Figure 26: Chromogenic pH-dependent bis-crown chemosensor 44 for diamines.
Figure 27: Triamine guests for binding to receptor 44.
Figure 28: Chiral bis-crown phenolphthalein chemosensors 46.
Figure 29: Crown ether amino acid 47.
Figure 30: Luminescent receptor 48 for bis-alkylammonium guests.
Figure 31: Luminescent CEAA (49a), a bis-CEAA receptor for amino acids (49b) and the structure of lysine bindi...
Figure 32: Luminescent CEAA tripeptide for binding small peptides.
Figure 33: Bis crown ether 51a self assembles co-operatively with C60-ammonium ion 51b.
Figure 34: Triptycene-based macrotricyclic dibenzo-[24]-crown-8 ether host 52 and guests.
Figure 35: Copper imido diacetic acid azacrown receptor 53a and the suggested His-Lys binding motif; a copper ...
Figure 36: Urea (54) and thiourea (55) benzo crown receptor for transport and extraction of amino acids.
Figure 37: Crown pyryliums ion receptors 56 for amino acids.
Figure 38: Ditopic sulfonamide bridged crown ether receptor 57.
Figure 39: Luminescent peptide receptor 58.
Figure 40: Luminescent receptor 59 for the detection of D-glucosamine hydrochloride in water/ethanol and lumin...
Figure 41: Guanidinium azacrown receptor 61 for simple amino acids and ditopic receptor 62 with crown ether an...
Figure 42: Chiral bicyclic guanidinium azacrown receptor 63 and similar receptor 64 for the enantioselective t...
Figure 43: Receptors for zwitterionic species based on luminescent CEAAs.
Figure 44: 1,10-Azacrown ethers with sugar podand arms and the anticancer agent busulfan.
Figure 45: Benzo-18-crown-6 modified β-cyclodextrin 69 and β-cyclodextrin functionalized with diaza-18-crown-6...
Figure 46: Receptors for colorimetric detection of primary and secondary ammonium ions.
Figure 47: Porphyrine-crown-receptors 72.
Figure 48: Porphyrin-crown ether conjugate 73 and fullerene-ammonium ion guest 74.
Figure 49: Calix[4]arene (75a), homooxocalix[4]arene (75b) and resorcin[4]arene (75c) compared (R = H, alkyl c...
Figure 50: Calix[4]arene and ammonium ion guest (R = H, alkyl, OAcyl etc.), possible binding sites; A: co-ordi...
Figure 51: Typical guests for studies with calixarenes and related molecules.
Figure 52: Lower rim modified p-tert-butylcalix[5]arenes 82.
Figure 53: The first example of a water soluble calixarene.
Figure 54: Sulfonated water soluble calix[n]arenes that bind ammonium ions.
Figure 55: Displacement assay for acetylcholine (3) with a sulfonato-calix[6]arene (84b).
Figure 56: Amino acid inclusion in p-sulfonatocalix[4]arene (84a).
Figure 57: Calixarene receptor family 86 with upper and lower rim functionalization.
Figure 58: Calix[6]arenes 87 with one carboxylic acid functionality.
Figure 59: Sulfonated calix[n]arenes with mono-substitution at the lower rim systematically studied on their r...
Figure 60: Cyclotetrachromotropylene host (91) and its binding to lysine (81c).
Figure 61: Calixarenes 92 and 93 with phosphonic acids groups.
Figure 62: Calix[4]arene tetraphosphonic acid (94a) and a double bridged analogue (94b).
Figure 63: Calix[4]arene tetraphosphonic acid ester (92c) for surface recognition experiments.
Figure 64: Calixarene receptors 95 with α-aminophosphonate groups.
Figure 65: A bridged homocalix[3]arene 95 and a distally bridged homocalix[4]crown 96.
Figure 66: Homocalix[3]arene ammonium ion receptor 97a and the Reichardt’s dye (97b) for colorimetric assays.
Figure 67: Chromogenic diazo-bridged calix[4]arene 98.
Figure 68: Calixarene receptor 99 by Huang et al.
Figure 69: Calixarenes 100 reported by Parisi et al.
Figure 70: Guest molecules for inclusion in calixarenes 100: DAP × 2 HCl (101a), APA (101b) and Lys-OMe × 2 HC...
Figure 71: Different N-linked peptido-calixarenes open and with glycol chain bridges.
Figure 72: (S)-1,1′-Bi-2-naphthol calixarene derivative 104 published by Kubo et al.
Figure 73: A chiral ammonium-ion receptor 105 based on the calix[4]arene skeleton.
Figure 74: R-/S-phenylalaninol functionalized calix[6]arenes 106a and 106b.
Figure 75: Capped homocalix[3]arene ammonium ion receptor 107.
Figure 76: Two C3 symmetric capped calix[6]arenes 108 and 109.
Figure 77: Phosphorous-containing rigidified calix[6]arene 110.
Figure 78: Calix[6]azacryptand 111.
Figure 79: Further substituted calix[6]azacryptands 112.
Figure 80: Resorcin[4]arene (75c) and the cavitands (113).
Figure 81: Tetrasulfonatomethylcalix[4]resorcinarene (114).
Figure 82: Resorcin[4]arenes (115a/b) and pyrogallo[4]arenes (115c, 116).
Figure 83: Displacement assay for acetylcholine (3) with tetracyanoresorcin[4]arene (117).
Figure 84: Tetramethoxy resorcinarene mono-crown-5 (118).
Figure 85: Components of a resorcinarene based displacement assay for ammonium ions.
Figure 86: Chiral basket resorcin[4]arenas 121.
Figure 87: Resorcinarenes with deeper cavitand structure (122).
Figure 88: Resorcinarene with partially open deeper cavitand structure (123).
Figure 89: Water-stabilized deep cavitands with partially structure (124, 125).
Figure 90: Charged cavitands 126 for tetralkylammonium ions.
Figure 91: Ditopic calix[4]arene receptor 127 capped with glycol chains.
Figure 92: A calix[5]arene dimer for diammonium salt recognition.
Figure 93: Calixarene parts 92c and 129 for the formation molecular capsules.
Figure 94: Encapsulation of a quaternary ammonium cation by two resorcin[4]arene molecules (NMe4+@[75c]2 × Cl−...
Figure 95: Encapsulation of a quaternary ammonium cation by six resorcin[4]arene molecules (NMe3D+@[130]6 × Cl−...
Figure 96: Structure and schematic of cucurbit[6]uril (CB[6], 131a).
Figure 97: Cyclohexanocucurbit[6]uril (CB′[6], 132) and the guest molecule spermine (133).
Figure 98: α,α,δ,δ-Tetramethylcucurbit[6]uril (134).
Figure 99: Structure of the cucurbituril-phthalhydrazide analogue 135.
Figure 100: Organic cavities for the displacement assay for amine differentiation.
Figure 101: Displacement assay methodology for diammonium- and related guests involving cucurbiturils and some ...
Figure 102: Nor-seco-Cucurbituril (±)-bis-ns-CB[6] (140) and guest molecules.
Figure 103: The cucurbit[6]uril based complexes 141 for chiral discrimination.
Figure 104: Cucurbit[7]uril (131c) and its ferrocene guests (142) opposed.
Figure 105: Cucurbit[7]uril (131c) guest inclusion and representative guests.
Figure 106: Cucurbit[7]uril (131c) binding to succinylcholine (145) and different bis-ammonium and bis-phosphon...
Figure 107: Paraquat-cucurbit[8]uril complex 149.
Figure 108: Gluconuril-based ammonium receptors 150.
Figure 109: Examples of clefts (151a), tweezers (151b, 151c, 151d) and clips (151e).
Figure 110: Kemp’s triacid (152a), on example of Rebek’s receptors (152b) and guests.
Figure 111: Amino acid receptor (154) by Rebek et al.
Figure 112: Hexagonal lattice designed hosts by Bell et al.
Figure 113: Bell’s amidinium receptor (156) and the amidinium ion (157).
Figure 114: Aromatic phosphonic acids.
Figure 115: Xylene phosphonates 159 and 160a/b for recognition of amines and amino alcohols.
Figure 116: Bisphosphonate recognition motif 161 for a colorimetric assay with alizarin complexone (163) for ca...
Figure 117: Bisphosphonate/phosphate clip 164 and bisphosphonate cleft 165.
Figure 118: N-Methylpyrazine 166a, N-methylnicotinamide iodide (166b) and NAD+ (166c).
Figure 119: Bisphosphate cavitands.
Figure 120: Bisphosphonate 167 of Schrader and Finocchiaro.
Figure 121: Tweezer 168 for noradrenaline (80b).
Figure 122: Different tripods and heparin (170).
Figure 123: Squaramide based receptors 172.
Figure 124: Cage like NH4+ receptor 173 of Kim et al.
Figure 125: Ammonium receptors 174 of Chin et al.
Figure 126: 2-Oxazolin-based ammonium receptors 175a–d and 176 by Ahn et al.
Figure 127: Racemic guest molecules 177.
Figure 128: Tripods based on a imidazole containing macrocycle (178) and the guest molecules employed in the st...
Figure 129: Ammonium ion receptor 180.
Figure 130: Tetraoxa[3.3.3.3]paracyclophanes 181 and a cyclophanic tetraester (182).
Figure 131: Peptidic bridged paraquat-cyclophane.
Figure 132: Shape-selective noradrenaline host.
Figure 133: Receptor 185 for binding of noradrenaline on surface layers from Schrader et al.
Figure 134: Tetraphosphonate receptor for binding of noradrenaline.
Figure 135: Tetraphosphonate 187 of Schrader and Finocchiaro.
Figure 136: Zinc-Porphyrin ammonium-ion receptors 188 and 189 of Mizutani et al.
Figure 137: Zinc porphyrin receptor 190.
Figure 138: Zinc porphyrin receptors 191 capable of amino acid binding.
Figure 139: Zinc-porphyrins with amino acid side chains for stereoinduction.
Figure 140: Bis-zinc-bis-porphyrin based on Tröger’s base 193.
Figure 141: BINAP-zinc-prophyrin derivative 194 and it’s guests.
Figure 142: Bisaryl-linked-zinc-porphyrin receptors.
Figure 143: Bis-zinc-porphyrin 199 for diamine recognition and guests.
Figure 144: Bis-zinc-porphyrin crown ether 201.
Figure 145: Bis-zinc-porphyrin 202 for stereodiscrimination (L = large substituent; S = small substituent).
Figure 146: Bis-zinc-porphyrin[3]rotaxane and its copper complex and guests.
Figure 147: Dien-bipyridyl ligand 206 for co-ordination of two metal atoms.
Figure 148: The ligand and corresponding tetradentate co-complex 207 serving as enantioselective receptor for a...
Figure 149: Bis(oxazoline)–copper(II) complex 208 for the recognition of amino acids in aqueous solution.
Figure 150: Zinc-salen-complexes 209 for the recognition tertiary amines.
Figure 151: Bis(oxazoline)–copper(II) 211 for the recognition of amino acids in aqueous solution.
Figure 152: Zn(II)-complex of a C2 terpyridine crown ether.
Figure 153: Displacement assay and receptor for aspartate over glutamate.
Figure 154: Chiral complex 214 for a colorimetric displacement assay for amino acids.
Figure 155: Metal complex receptor 215 with tripeptide side arms.
Figure 156: A sandwich complex 216 and its displaceable dye 217.
Figure 157: Lanthanide complexes 218–220 for amino acid recognition.
Figure 158: Nonactin (221), valinomycin (222) and vancomycin (223).
Figure 159: Monesin (224a) and a chiral analogue for enantiodiscrimination of ammonium guests (224b).
Figure 160: Chiral podands (226) compared to pentaglyme-dimethylether (225) and 18-crown-6 (4).
Figure 161: Lasalocid A (228).
Figure 162: Lasalocid derivatives (230) of Sessler et al.
Figure 163: The Coporphyrin I tetraanion (231).
Figure 164: Linear and cyclic peptides for ammonium ion recognition.
Figure 165: Cyclic and bicyclic depsipeptides for ammonium ion recognition.
Figure 166: α-Cyclodextrin (136a) and novocaine (236).
Figure 167: Helical diol receptor 237 by Reetz and Sostmann.
Figure 168: Ammonium binding spherand by Cram et al. (238a) and the cyclic[6]metaphenylacetylene 238b in compar...
Figure 169: Receptor for peptide backbone and ammonium binding (239).
Figure 170: Anion sensor principle with 3-hydroxy-2-naphthanilide of Jiang et al.
Figure 171: 7-bromo-3-hydroxy-N-(2-hydroxyphenyl)naphthalene 2-carboxamide (241) and its amine binding.
Figure 172: Naturally occurring catechins with affinity to quaternary ammonium ions.
Figure 173: Spiropyran (244) and merocyanine form (244a) of the amino acid receptors of Fuji et al.
Figure 174: Coumarin aldehyde (245) and its iminium species with amino acid bound (245a) by Glass et al.
Figure 175: Coumarin aldehyde appended with boronic acid.
Figure 176: Quinolone aldehyde dimers by Glass et al.
Figure 177: Chromogenic ammonium ion receptors with trifluoroacetophenone recognition motifs.
Figure 178: Chromogenic ammonium ion receptor with trifluoroacetophenone recognition motif bound on different m...
Synthetic incorporation of Nile Blue into DNA using 2′-deoxyriboside substitutes: Representative comparison of (R)- and (S)-aminopropanediol as an acyclic linker
- Daniel Lachmann,
- Sina Berndl,
- Otto S. Wolfbeis and
- Hans-Achim Wagenknecht
Beilstein J. Org. Chem. 2010, 6, No. 13, doi:10.3762/bjoc.6.13
- state fluorescence spectra of the Nile Blue-modified single and double strands using an excitation wavelength of 610 nm (Figure 2). The emission maximum of the chromophore is shifted from 665 nm (in case of the isolated dye in ethanol) to 677–679 nm for the modified DNA single and double strands. In
- this chromophore to DNA. We interpret the similarity of the absorption properties together with the results from the thermal dehybridization studies, as discussed above, as a result of the intercalation of the Nile Blue dye in duplex DNA. To further explore the optical properties we recorded steady
Graphical Abstract
Scheme 1: Chirality of C-3 of natural 2′-deoxyribofuranosides (left) in comparison with the acyclic D-threoni...
Scheme 2: Synthesis of the R-configured DNA building block 3 and postsynthetic click ligation of the Nile Blu...
Figure 1: UV–vis absorption spectra of single-stranded DNA1 and DNA2, and the corresponding duplexes DNA1Y an...
Figure 2: Fluorescence spectra of single-stranded DNA1 and DNA2, and corresponding duplexes DNA1Y and DNA2Y (...
Figure 3: Models for DNA1A bearing the (R)-3-amino-1,2-propanediol linker (left) and the corresponding duplex...
