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Search for "photostability" in Full Text gives 44 result(s) in Beilstein Journal of Organic Chemistry.
Synthesis of π-conjugated polycyclic compounds by late-stage extrusion of chalcogen fragments
Beilstein J. Org. Chem. 2024, 20, 287–305, doi:10.3762/bjoc.20.30
- thermal- and photostability by the choice of oxygen as heteroatom, while keeping the possibility to trigger chalcogen extrusion via a radically different mechanistic route, as a result of the injection of electrons. Here, the presence of the imide functions appended to the naphthyl scaffold is crucial
Photochromic derivatives of indigo: historical overview of development, challenges and applications
Beilstein J. Org. Chem. 2024, 20, 228–242, doi:10.3762/bjoc.20.23
- Despite thousands of years of use, the demand for indigo derivatives in the industry is still growing. The main reason for this is the unusual photostability and color fastness of indigo as industrial dye. This exceptional photostability of indigo and its derivatives has attracted significant scientific
- the O atom (Figure 6b). Moreover, the data of the first systematic computational ab initio study of the molecular mechanism of the photostability of indigo [36] support these findings and additionally point out that the single proton transfer (SPT) is more favorable than the double proton transfer
A series of perylene diimide cathode interlayer materials for green solvent processing in conventional organic photovoltaics
Beilstein J. Org. Chem. 2023, 19, 1620–1629, doi:10.3762/bjoc.19.119
- ]. However, while progress has been made by increases in PCEs from ≈10% to ≈19% in the last decade, many of the materials used in OPVs suffer from low thermal and/or photostability, lengthy syntheses, high cost, and require harmful reagents for synthesis and processing. Therefore, it is necessary to design
Discrimination of β-cyclodextrin/hazelnut (Corylus avellana L.) oil/flavonoid glycoside and flavonolignan ternary complexes by Fourier-transform infrared spectroscopy coupled with principal component analysis
Beilstein J. Org. Chem. 2023, 19, 380–398, doi:10.3762/bjoc.19.30
- compounds [5]. The resulting supramolecular inclusion complexes provide enhanced water solubility and bioavailability/bioaccessibility of the nanoencapsulated bioactive compounds, higher oxidative and thermal stability or photostability of labile compounds, and their controlled release [6][7]. Vegetable oil
Photophysical, photostability, and ROS generation properties of new trifluoromethylated quinoline-phenol Schiff bases
Beilstein J. Org. Chem. 2021, 17, 2799–2811, doi:10.3762/bjoc.17.191
- more polar solvents (DMSO; 65–150 nm and MeOH; 65–130 nm) than in CHCl3 (59–85 nm). Compounds 3 presented good stability under white-LED irradiation conditions and moderate ROS generation properties were observed. Keywords: photophysical properties; photostability; quinoline; ROS generation; Schiff
- trifluoromethylated hybrid system comprising the Schiff base scaffolds from some 6-aminoquinolines and salicylaldehyde derivatives in order to analyze and evaluate their photophysical, photostability, and antioxidant properties for possible future applications in the pharmacological areas or materials sciences
- attributed to a greater electronic conjugation provided by the imine function present in the molecules of the series 3. Photostability and singlet oxygen quantum yield (ΦΔ) assays In order to be efficient for applications in photobiology, organic dyes must be stable when subjected to light irradiation for
Visible-light-mediated copper photocatalysis for organic syntheses
Beilstein J. Org. Chem. 2021, 17, 2520–2542, doi:10.3762/bjoc.17.169
- ; however, they suffer from relatively poor photostability [14][15][16]. Transition-metal-photoredox catalysts, such as ruthenium and iridium polypyridyl complexes, exhibit high redox potentials, long excited state lifetimes, and strong absorption [17][18][19][20]. However, high cost and their scarcity
- the homoleptic and heteroleptic CuI complexes [22][31][36]. The introduction of bulky ligand substituents might efficiently prevent the reorganization of the excited state. Thus, changing the nature of the chelating ligand can improve the photostability and lifetime of the excited state to meet the
Recent advances in the application of isoindigo derivatives in materials chemistry
Beilstein J. Org. Chem. 2021, 17, 1533–1564, doi:10.3762/bjoc.17.111
- polymer with an effective ratio μh/μe = 3.94 cm2⋅V−1⋅s−1/3.50 cm2⋅V−1⋅s−1. Recently, diketopyrrolo[3,4-c]pyrrole (DPP) derivatives, which are highly conjugated electron-withdrawing heterocycles with high charge conductivity, broad absorption spectrum, photostability, and thermal stability have attracted
Multiswitchable photoacid–hydroxyflavylium–polyelectrolyte nano-assemblies
Beilstein J. Org. Chem. 2021, 17, 166–185, doi:10.3762/bjoc.17.17
- spectroscopy, and isothermal titration calorimetry. Results and Discussion Characterization of the flavy building block In the first step the switchability and the photostability of pelargonidin chloride (Flavy) were investigated. The switching ability of Flavy is already well-known [79][80]. Here it was
Vicinal difluorination as a C=C surrogate: an analog of piperine with enhanced solubility, photostability, and acetylcholinesterase inhibitory activity
Beilstein J. Org. Chem. 2020, 16, 2663–2670, doi:10.3762/bjoc.16.216
- this might increase the accessibility of conformer 2f. We reasoned that comparing the biological activities of 1 vs 2 might shed light on this possibility (vide infra). Photostability A limitation of piperine (1) as a drug lead is its instability under UV light. The conjugated system of 1 is well-known
- physicochemical properties of compound 2 were found to be superior to piperine (1) itself in two key respects, namely photostability and aqueous solubility. The conformational analysis of 2 by DFT and NMR spectroscopy revealed that the lowest-energy conformations 2a–c are imperfect mimics of 1 but that a somewhat
- = hydroxybenzotriazole, DMF = N,N-dimethylformamide. Supporting Information Supporting Information File 402: Synthetic procedures, characterization data for novel compounds and copies of spectra; photostability assessment, conformational analysis of compound 2, and biological assays.
Heterogeneous photocatalysis in flow chemical reactors
Beilstein J. Org. Chem. 2020, 16, 1495–1549, doi:10.3762/bjoc.16.125
- , wide electrochemical redox potentials, and photostability. However, these photocatalysts present serious drawbacks, such as toxicity, limited availability, and the overall cost of rare transition metal elements. This reduces their long-term viability, especially at an industrial scale. Heterogeneous
- separation and recycling, HPCats show advantages such as an enhanced photostability and selectivity [47][48]. A heterogeneous catalyst with a high surface area is often associated with a greater number of surface-active sites for catalysis to occur and makes morphological control critical to the catalyst
Recent applications of porphyrins as photocatalysts in organic synthesis: batch and continuous flow approaches
Beilstein J. Org. Chem. 2020, 16, 917–955, doi:10.3762/bjoc.16.83
- superoxide radical anion by a reductive quenching and the rearrangement of the hydroperoxide intermediate [41]. The heterogeneous protocol using MOF porphyrins was significantly faster than the corresponding homogeneous photocatalysis, which was attributed to higher photostability of the porphyrins as MOF
- increase of singlet oxygen generation and photocatalytic activity under the sunlight irradiation. Furthermore, the steric hindrance around the porphyrin core, caused by the diacids, enhanced the catalyst photostability, allowing a lowers porphyrin load. The authors evaluated various protonated-TPPs, using
Regioselectively α- and β-alkynylated BODIPY dyes via gold(I)-catalyzed direct C–H functionalization and their photophysical properties
Beilstein J. Org. Chem. 2020, 16, 587–595, doi:10.3762/bjoc.16.53
- optical features such as intense and narrow S0–S1 absorption and emission bands in the visible-to-near-infrared region, a high fluorescence quantum yield, and good photostability. For the applications mentioned above, various BODIPY dyes functionalized at the meso-, α-, and β-pyrrolic positions have been
Reversible photoswitching of the DNA-binding properties of styrylquinolizinium derivatives through photochromic [2 + 2] cycloaddition and cycloreversion
Beilstein J. Org. Chem. 2020, 16, 111–124, doi:10.3762/bjoc.16.13
- DNA only weakly by outside-edge association. Most notably, it was possible to switch between those two binding modes by irradiation with different excitation wavelengths (Scheme 3). Although the system still has to be improved with respect to photostability, it may be considered as a promising
Fluorinated maleimide-substituted porphyrins and chlorins: synthesis and characterization
Beilstein J. Org. Chem. 2019, 15, 2704–2709, doi:10.3762/bjoc.15.263
- the biological efficiency of the photosensitizing agents [21][22]. At the same time fluorinated porphyrins are well known for their photostability and efficiency in generating long-lived triplet excited states through intersystem crossing (ISC) with minimal energy loss from excited states, and are
A photochemical determination of luminescence efficiency of upconverting nanoparticles
Beilstein J. Org. Chem. 2019, 15, 2671–2677, doi:10.3762/bjoc.15.260
- lanthanides used. The main application foreseen for these nanomaterials is as a substitute of quantum dots [3], since the combination of anti-Stokes emission and noncoherent absorption prevent any luminescence background. Their extreme photostability [4] make them also ideal candidates for single particle
Plasma membrane imaging with a fluorescent benzothiadiazole derivative
Beilstein J. Org. Chem. 2019, 15, 2644–2654, doi:10.3762/bjoc.15.257
- -soluble and selective bioprobe for plasma membrane imaging. The new compound was efficiently synthesized in a two-step procedure with good yields. The photophysical properties were evaluated and the dye proved to have an excellent photostability in several solvents. DFT calculations were found in
- ETN vs Stokes shifts using the values provided by Richardt [44] were found in accordance with the ICT proposition and the calculated linear correlation from the plots [45] corroborated this proposition. The photostability of the new compound was measured in aqueous media as a preclude of the
- -soluble BTD fluorophore BTD-4APTEG was developed and applied as selective probe for bioimaging and stained plasma membranes selectively in the tested cells lines. The features envisaged for the synthesis of the structure proved to be capable of granting the dye water solubility, good photostability and
In search of visible-light photoresponsive peptide nucleic acids (PNAs) for reversible control of DNA hybridization
Beilstein J. Org. Chem. 2019, 15, 2500–2508, doi:10.3762/bjoc.15.243
- complementary DNA. For this purpose, we decided to measure thermal melting curves. Beforehand we verified the photostability of cis-PNA12(oF4Azo) (3) in the temperature ramp from 20 °C to 90 °C by UV–vis spectroscopy. We observed that the cis-isomer was always stable during the whole temperature range (Figure
Effect of ring size on photoisomerization properties of stiff stilbene macrocycles
Beilstein J. Org. Chem. 2019, 15, 2408–2418, doi:10.3762/bjoc.15.233
- largest macrocycle (linked by a twelve carbon chain) is significantly higher than that of the stiff stilbene unit itself. In general, it is indicated that addition of even a flexible chain to the stiff stilbene unit may significantly affect its photochemical properties and increase the photostability of
- the resulting macrocycle. Keywords: DFT; molecular mechanics; photostability; photo-switch; ring-strain; stiff stilbene; Introduction The stiff stilbene (SS) molecule has drawn a lot of interest due to its photodynamic properties [1]. Stiff stilbenes typically undergo light triggered isomerization
Synthesis of a dihalogenated pyridinyl silicon rhodamine for mitochondrial imaging by a halogen dance rearrangement
Beilstein J. Org. Chem. 2019, 15, 2333–2343, doi:10.3762/bjoc.15.226
- Pearson coefficient ≥0.9 [46]. However, dye 15 has the benefit of further red-shifted absorption and emission properties as well as a photostability that allows for STED (stimulated emission depletion) nanoscopy [52][53]. As the 2-chloropyridinyl moiety in SiR dye 15 targets acidic cellular compartments
- stains mitochondria without background from unspecific membrane staining. However, higher photostability and a lower saturation intensity for STED result in a better performance in time-lapse live cell STED imaging of MitoESq-635. Taken together, our SiR dye 15 is a valid compromise between MitoESq-635
A golden opportunity: benzofuranone modifications of aurones and their influence on optical properties, toxicity, and potential as dyes
Beilstein J. Org. Chem. 2019, 15, 1781–1785, doi:10.3762/bjoc.15.171
- well as its longer term retention and photostability are required. Conclusion In conclusion, the benzofuranone portion of the aurone skeleton does have a definite impact on both the UV–vis spectral and cytotoxicity properties of aurones. Interestingly, the position of the substituent was often more
An azobenzene container showing a definite folding – synthesis and structural investigation
Beilstein J. Org. Chem. 2019, 15, 1534–1544, doi:10.3762/bjoc.15.156
- , the trans→cis isomerization is triggered by UV light whereas the cis→trans back relaxation takes place by visible light or heat [30][42]. Due to the high reversibility, the simple synthesis and the high photostability azobenzene derivatives are the most commonly used switching units. A further
Precious metal-free molecular machines for solar thermal energy storage
Beilstein J. Org. Chem. 2019, 15, 1096–1106, doi:10.3762/bjoc.15.106
- , their structures predispose to an easy functionalization and low cost synthesis. Another advantage of these dyes is the very low molar absorptivity [16][17] of the higher energy cis isomer, which is a prerequisite for its photostability. The cis isomers of styryl dyes linked to crown ethers have been
Design and synthesis of multivalent α-1,2-trimannose-linked bioerodible microparticles for applications in immune response studies of Leishmania major infection
Beilstein J. Org. Chem. 2019, 15, 623–632, doi:10.3762/bjoc.15.58
- of the commercially available rhodamine dye, TAMRA (555ex/580em), to the dendrimer would allow for standard immunofluorescence assays, to track the microparticle following cellular uptake and intracellular processing. TAMRA’s high photostability, low pH sensitivity and ease of incorporation through
Rational design of boron-dipyrromethene (BODIPY) reporter dyes for cucurbit[7]uril
Beilstein J. Org. Chem. 2018, 14, 1961–1971, doi:10.3762/bjoc.14.171
- macrocyclic hosts and dyes that have so far been reported [16] are only of limited use for these currently emerging life science applications of CBs. Many of the fluorescent dyes which bind to CBs with significant fluorescence changes have a limited photostability, in particular under intense laser light
- complex formation of the BODIPY core, the photostability of the dyes was not affected by CB7 complex formation (Figure S20, Supporting Information File 1). The compatibility of BODIPYs with common excitation sources and filter sets also enables their use in fluorescence microscopy. To demonstrate, we have
Halogen-containing thiazole orange analogues – new fluorogenic DNA stains
Beilstein J. Org. Chem. 2017, 13, 2902–2914, doi:10.3762/bjoc.13.283
- chromophores have been studied by Armitage and co-workers [42][43]. According to these studies the fluorination of the symmetrical [42] and unsymmetrical [43] cyanine dyes results in reduced aggregation and significantly improved the photostability and photophysical properties of the dyes. The authors [43
- spectra and is in contrast to the by Armitage et al. observed influence of the replacement of hydrogen with fluorine atom in the benzothiazole ring [43]. Photostability The photostability of all dyes in the series was evaluated in acetonitrile with irradiation at 254 nm with a mercury lamp in equal
- intervals of two minutes and the results were compared with those obtained for the commercial dye TO. All dyes show similar photostability to TO except for dye 5c, which has a much higher photostability than the commercial dye (Figure 4). All dyes from the series demonstrate much higher photostability upon
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