Search results
Search for "toxicity" in Full Text gives 359 result(s) in Beilstein Journal of Organic Chemistry. Showing first 200.
One-pot synthesis of oxazolidinones and five-membered cyclic carbonates from epoxides and chlorosulfonyl isocyanate: theoretical evidence for an asynchronous concerted pathway
Beilstein J. Org. Chem. 2020, 16, 1805–1819, doi:10.3762/bjoc.16.148
- pharmaceutical products [15]. Moreover, they are used as electrolyte components in Li-ion rechargeable cells and as aprotic polar solvent with high boiling point as alternative of dangerous solvents because of their good biodegradability and low toxicity [16][17][18]. Synthetic intermediates for ring-opening
Clickable azide-functionalized bromoarylaldehydes – synthesis and photophysical characterization
Beilstein J. Org. Chem. 2020, 16, 1683–1692, doi:10.3762/bjoc.16.139
- inert conditions [28] are necessary to facilitate an afterglow emission. Most phosphorescence studies are focused on metal complexes due to a strong heavy atom-induced spin-orbit coupling [29][30][31][32][33]. Considering the high price and the toxicity of many metal complexes, pure organic phosphors
Fluorohydration of alkynes via I(I)/I(III) catalysis
Beilstein J. Org. Chem. 2020, 16, 1627–1635, doi:10.3762/bjoc.16.135
- C(sp3)–C(sp3) bond-forming reactions [16][17], and closely resembles one of the very few biological blueprints for the preparation of fluorine-containing materials [18][19][20][21]. However, in translating the fluoroacetate-like building blocks to a laboratory paradigm, the intrinsic toxicity of
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
4-Hydroxy-3-methyl-2(1H)-quinolone, originally discovered from a Brassicaceae plant, produced by a soil bacterium of the genus Burkholderia sp.: determination of a preferred tautomer and antioxidant activity
Beilstein J. Org. Chem. 2020, 16, 1489–1494, doi:10.3762/bjoc.16.124
- immunity [33], among which redox enzymes and antioxidants are the direct countermeasures to neutralize the toxicity of ROS [34]. Limited examples of antioxidants include catecholamine melanin from a fungus Cryptococcus neoformans [35], 1,8-dihydroxynaphthalene melanin from fungi Wangiella dermatitidis and
Synthesis, antiinflammatory activity, and molecular docking studies of bisphosphonic esters as potential MMP-8 and MMP-9 inhibitors
Beilstein J. Org. Chem. 2020, 16, 1277–1287, doi:10.3762/bjoc.16.108
- % edema inhibition) on a TPA topical model. Next, to assess the acute toxicity of the synthesized derivatives, test animals were administered with 50–100 mg/kg of 3–6, respectively, by an oral route, and after 14 days, neither lethality nor a significative weight loss were observed. Finally, a structure
- describe the enzyme inhibitor site binding modes [16][17][18]. Thus, in this work, the bisphosphonates 3–6 were synthesized by a two-step method and then evaluated through two in vivo acute inflammation models in BALB/c mice. Furthermore, the acute toxicity was determined for these derivatives, and
- antiinflammatory activity evaluation of the bisphosphonic esters 1 and 2, observing activity by oral (carrageenan model) and topical administration (TPA model) in BALB/c mice (Figure 1) [19]. Furthermore, in the search of more potent and low-toxicity derivatives, in this work, we have focussed our attention on the
Photocatalysis with organic dyes: facile access to reactive intermediates for synthesis
Beilstein J. Org. Chem. 2020, 16, 1163–1187, doi:10.3762/bjoc.16.103
- states with different classes of molecules. However, the relatively high cost of these photocatalysts, their toxicity, and the limited abundance of the coordinating transition metals can hamper their applicability [13]. For these reasons, the quest for cheaper, more sustainable, and environmentally
Development of fluorinated benzils and bisbenzils as room-temperature phosphorescent molecules
Beilstein J. Org. Chem. 2020, 16, 1154–1162, doi:10.3762/bjoc.16.102
- (e.g., Ru [14], Ir [15][16], Pt [17], and Au [18][19][20][21]) (Figure 1A), and this offers a molecular design approach for phosphorescence emission. However, it is becoming necessary to explore alternatives to rare metals because of the latter’s scarcity and toxicity. Owing to recent considerable
Rhodium-catalyzed reductive carbonylation of aryl iodides to arylaldehydes with syngas
Beilstein J. Org. Chem. 2020, 16, 645–656, doi:10.3762/bjoc.16.61
- heterogeneous systems contained: PdO/Co3O4 with K2CO3 [33], MCM-41-S-PdCl2 [34], and MCM-41-2P-PdCl2 [35]. However, the aforementioned systems often suffer from high toxicity of solvents, high pressure of gases or high reaction temperatures, which make these protocols inapplicable for large scale applications
A systematic review on silica-, carbon-, and magnetic materials-supported copper species as efficient heterogeneous nanocatalysts in “click” reactions
Beilstein J. Org. Chem. 2020, 16, 551–586, doi:10.3762/bjoc.16.52
- reactions, Ugi–Smiles reactions, Mizoroki–Heck reactions, aldol reactions, oxidation and dehydration reactions, Mannich reactions, and multicomponent reactions. Because of the mentioned reasons as well as due to the low toxicity of silica nanoparticles, they are often a good option [24]. For this review
- ]. Because of the mentioned reasons, as well as due to the low toxicity and the magnetically reusability of these nanoparticles, they were also used in organic reactions. As such, in this review, we provide an overview on the synthesis and functionalization of MNPs and on investigations on their catalytic
Recent advances in photocatalyzed reactions using well-defined copper(I) complexes
Beilstein J. Org. Chem. 2020, 16, 451–481, doi:10.3762/bjoc.16.42
- be developed. Among them, the use of first-row transition metals [8][9], particularly copper, is an interesting approach [10][11][12][13]. The high abundance, low price, low toxicity, and intrinsic properties (redox potential, four oxidation states, etc.) of copper are excellent and promising
Room-temperature Pd/Ag direct arylation enabled by a radical pathway
Beilstein J. Org. Chem. 2020, 16, 384–390, doi:10.3762/bjoc.16.36
- reduce waste and toxicity by removing the need for stoichiometric amounts of toxic organometallics [2]. While significant progress has been made in DArP, C–H bonds are more challenging to functionalize than their C–M counterparts. Known DArP conditions have limited monomers that can produce polymers with
Copper-promoted/copper-catalyzed trifluoromethylselenolation reactions
Beilstein J. Org. Chem. 2020, 16, 305–316, doi:10.3762/bjoc.16.30
- , the incorporation of OCF3 as well as SCF3 is routinely used to design new active compounds [8]. The development of new methodologies based on copper catalysis/chemistry is playing a pivotal role due to the low cost and toxicity of the corresponding copper reagents [9]. Due to their stability, these
Recent developments in photoredox-catalyzed remote ortho and para C–H bond functionalizations
Beilstein J. Org. Chem. 2020, 16, 248–280, doi:10.3762/bjoc.16.26
- noteworthy renaissance not only because of the lower toxicity, stability, speed, and efficiency of the method, but also thanks to the easy generation of radical species and the formation of a long-lived triplet excited state under photoirradiation that can behave as a reductant as well as an oxidant [51][52
- catalysts, such as low toxicity, their functioning at room temperature, and smooth irradiation requirements with low-energy lights (e.g., LEDs, fluorescent bulbs, etc.) made this area of research very interesting. Within a very short time, photoredox catalysis has emerged as an important future direction
Efficient method for propargylation of aldehydes promoted by allenylboron compounds under microwave irradiation
Beilstein J. Org. Chem. 2020, 16, 168–174, doi:10.3762/bjoc.16.19
- ] or boron [26][27][28] to perform propargylation reactions typically requires catalysis by Lewis acids or bases and although the utility of allenylstannanes is further indicated by the commercial availability of some of them, the toxicity of these compounds makes them inappropriate for the use in
Potent hemithioindigo-based antimitotics photocontrol the microtubule cytoskeleton in cellulo
Beilstein J. Org. Chem. 2020, 16, 125–134, doi:10.3762/bjoc.16.14
- maintain photostationary state equilibria in cellulo [10]. We cross-checked different illumination wavelengths in cellular toxicity assays; in accordance with the DMSO photoswitching studies, we observed that 530 nm (ca. 97% Z-configuration, but additionally controls for non-specific phototoxicity
- observed its photoswitching in pure aqueous media, in the heterogeneous cellular environment, we found that its overall toxicity under lit conditions was reliably and reproducibly halved. We then explored changes to the substituent pattern to determine whether we could improve both Z-isomer potency in an
- disruption. Lastly, to substantiate the causative link between the observations on MT disruption and cellular toxicity, we examined the impacts of HITub-4 on the cell cycle. Tubulin-binding agents whose major cellular mechanism of toxic action is the disruption of MT dynamics or structure should cause cell
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
- intrinsic toxicity of the employed drugs [11][12][13]. As a result, there is an urgent need for DNA-targeting chemotherapeutic reagents that can be activated with an external stimulus only at the desired point of action. In this context, light offers several distinct advantages to switch on the activity of
Light-controllable dithienylethene-modified cyclic peptides: photoswitching the in vivo toxicity in zebrafish embryos
Beilstein J. Org. Chem. 2020, 16, 39–49, doi:10.3762/bjoc.16.6
- rerio, and determined the toxicities of the peptides in terms of 50% lethal doses (LD50). This study allowed us to: (i) demonstrate the feasibility of evaluating peptide toxicity with D. rerio larvae at 3–4 days post fertilization, (ii) determine the phototherapeutic safety windows for all peptides
- , (iii) demonstrate photoswitching of the whole-body toxicity for the dithienylethene-modified peptides in vivo, (iv) re-analyze previous structure–toxicity relationship data, and (v) select promising candidates for potential clinical development. Keywords: diarylethene photoswitch; gramicidin S
- plasma stability in vivo, limited understanding of their mechanisms of action, and high in vivo toxicity. The former two drawbacks are being adequately resolved [9] (e.g., by modifying the peptide backbone [10], macrocyclization [11], or by use of unnatural amino acids [12]), and mechanistic
Pigmentosins from Gibellula sp. as antibiofilm agents and a new glycosylated asperfuran from Cordyceps javanica
Beilstein J. Org. Chem. 2019, 15, 2968–2981, doi:10.3762/bjoc.15.293
- formation of Staphylococcus aureus DSM1104. The lack of toxicity toward the studied microorganism and cell lines of pigmentosin B (2), as well as the antimicrobial effect of pigmentosin A (1), made them good candidates for further development for use in combination therapy of infections involving biofilm
Palladium-catalyzed Sonogashira coupling reactions in γ-valerolactone-based ionic liquids
Beilstein J. Org. Chem. 2019, 15, 2907–2913, doi:10.3762/bjoc.15.284
- arylacetylenes [7][8] having great importance in organic synthetic schemes of the pharmaceutical industry. From the environmental point of view, the Sonogashira reactions are usually performed in fossil-based common organic reaction media having high vapor pressure even at higher temperatures, toxicity
Bacterial terpene biosynthesis: challenges and opportunities for pathway engineering
Beilstein J. Org. Chem. 2019, 15, 2889–2906, doi:10.3762/bjoc.15.283
- component analysis [140], qPCR/proteomics [141], and iterative grid search [142] to troubleshoot and guide the tuning of the promoter strengths and copy numbers of each module/enzyme (Figure 11b). Toxicity of biosynthetic intermediates, endogenous regulation, and stability of genetic constructs are the main
- accumulation of FPP (Figure 11c) [143]. Alternatively, in vitro pathway reconstitution led to the successful production of several monoterpenes, circumnavigating toxicity to the heterologous hosts [144]. Several intermediates are also known to inhibit enzyme activities in the pathway. Novel pathways, such as
Iodine-mediated hydration of alkynes on keto-functionalized scaffolds: mechanistic insight and the regiospecific hydration of internal alkynes
Beilstein J. Org. Chem. 2019, 15, 2747–2752, doi:10.3762/bjoc.15.265
- extremely harmful to environmental and biological systems [3]. In light of mercury’s toxicity, the synthetic community has given much attention to the use of less harmful reagents. Success has been obtained with many other transition metal salts, for example, palladium(II) [4][5], rhodium(III) [6], copper
Fluorinated maleimide-substituted porphyrins and chlorins: synthesis and characterization
Beilstein J. Org. Chem. 2019, 15, 2704–2709, doi:10.3762/bjoc.15.263
- ability to selectively accumulate in the target tissue, the absence of toxicity, toxic byproducts and mutagenic effects, and an opportunity for medical administration. An additional advantage of porphyrins is the possibility of functionalization of the macrocycle periphery with various substituents and
Synthesis of novel sulfide-based cyclic peptidomimetic analogues to solonamides
Beilstein J. Org. Chem. 2019, 15, 2544–2551, doi:10.3762/bjoc.15.247
- prevent the expression of Staphylococcus aureus virulence factors such as α-hemolysin and phenol-soluble modulins without affecting the bacterial growth [3]. Particularly, solonamide B and its analogues revealed no detectable toxicity against erythrocytes or human neutrophils [3][4]. Staphylococcus aureus
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
- Information File 1, compare STED images with their corresponding confocal images. By resolving the tubular structure of mitochondria, we prove successful application of our mitochondria-selective pyridinyl SiR 15 in STED nanoscopy. Toxicity of the pyridinyl silicon rhodamine 15 Although for PET examinations
- precursor 15. For toxicity assessment, the frequency and duration of cell division with and without incubation with dye 15 was analyzed via time-lapse holographic imaging (Figure 3). U2OS cells were incubated with 1 µM dye 15 in medium for 1 h and, after washing with dye free medium, continually imaged over
Other Beilstein-Institut Open Science Activities
