Efficient synthesis of fluorinated triphenylenes with enhanced arene–perfluoroarene interactions in columnar mesophases

• Yang Chen,
• Jiao He,
• Hang Lin,
• Hai-Feng Wang,
• Ping Hu,
• Bi-Qin Wang,
• Ke-Qing Zhao and
• Bertrand Donnio

Beilstein J. Org. Chem. 2024, 20, 3263–3273, doi:10.3762/bjoc.20.270

• concentration of 1 × 10−5 mol/L and in solid-state thin film. DFT calculated frontier molecular orbitals and optimized molecular structures for F1 and G11. Synthesis, yields, and nomenclature of 1,2,4-trifluoro-6,7,10,11-tetraalkoxy-3-(perfluorophenyl)triphenylene (Fn, n = 3–12) and corresponding 1,1',3,3',4,4

Discovery of ianthelliformisamines D–G from the sponge Suberea ianthelliformis and the total synthesis of ianthelliformisamine D

• Sasha Hayes,
• Yaoying Lu,
• Bernd H. A. Rehm and
• Rohan A. Davis

Beilstein J. Org. Chem. 2024, 20, 3205–3214, doi:10.3762/bjoc.20.266

• OD600 and resazurin (RSZ) metabolic assay, respectively. The final concentration of DMSO in the assays was 1% (v/v). The negative controls consisted of inoculum and 1% DMSO. The antibiotic tobramycin (Sigma-Aldrich; 16 µg/mL) was used as a positive control. The initial OD600 and final OD600 were read

Direct trifluoroethylation of carbonyl sulfoxonium ylides using hypervalent iodine compounds

• Radell Echemendía,
• Carlee A. Montgomery,
• Fabio Cuzzucoli,
• Antonio C. B. Burtoloso and
• Graham K. Murphy

Beilstein J. Org. Chem. 2024, 20, 3182–3190, doi:10.3762/bjoc.20.263

• reaction with Cs2CO3 (1.3 equiv) produced 3a in a much improved 60% yield (Table 1, entry 2). We screened other solvents and tested the impact of other inorganic bases but none of these changes improved the formation of the ylide 3a (Table 1, entries 3–6). And while increasing the reaction concentration

Multicomponent reactions driving the discovery and optimization of agents targeting central nervous system pathologies

• Lucía Campos-Prieto,
• Aitor García-Rey,
• Eddy Sotelo and
• Ana Mallo-Abreu

Beilstein J. Org. Chem. 2024, 20, 3151–3173, doi:10.3762/bjoc.20.261

• inhibitors, and their effects were investigated using the Amplex-Red® kit in C. elegans. Individuals exposed to compounds 2a, 2b, 2c, 2d, 2e, and 2f at a concentration of 1 mM were analyzed for AChE activity in their extracts. The results revealed significant inhibition of AChE levels, with compound 2e

• and 31.6 μM, respectively), which is the concentration required to double the specific luciferase reporter activity, compared to melatonin (CD = 66.4 µM). The results suggest that compounds 3a and 3b are promising as potent antioxidant therapeutic agents. Furthermore, the results of the ORAC-FL assay

• conducted at a concentration of 10 μM, with donepezil serving as a positive control. To measure their impact on cellular tau oligomerization, the fluorescence resonance energy transfer (FRET) signal intensity was quantified in a cellular tau FRET assay at the same 10 μM concentration, using MK-886, a known

Controlled oligomerization of [1.1.1]propellane through radical polarity matching: selective synthesis of SF₅- and CF₃SF₄-containing [2]staffanes

• Jón Atiba Buldt,
• Wang-Yeuk Kong,
• Yannick Kraemer,
• Masiel M. Belsuzarri,
• Ansh Hiten Patel,
• James C. Fettinger,
• Dean J. Tantillo and
• Cody Ross Pitts

Beilstein J. Org. Chem. 2024, 20, 3134–3143, doi:10.3762/bjoc.20.259

• to how favoring the path to INT2 may be achieved in practice through increasing concentration of 1. Subsequently, INT2 could abstract a Cl atom from SF5Cl via TS3 to form 2 or add to a third equiv of 1 through TS4, leading to INT3. Once again, Cl atom abstraction is thermodynamically (ΔΔG = −11.7

• here that the free energy of activation is lower for chlorination, albeit only by 0.4 kcal/mol. This is consistent with the notion that the kinetic preference can be overcome by increasing the concentration of 1 relative to CF3SF4Cl. In the second product-determining step, Cl atom abstraction by INT5

Advances in the use of metal-free tetrapyrrolic macrocycles as catalysts

• Mandeep K. Chahal

Beilstein J. Org. Chem. 2024, 20, 3085–3112, doi:10.3762/bjoc.20.257

• to Fc+) was reported to be very slow and independent of HTB concentration in the absence of 18 (H2TPP), suggesting that the porphyrin macrocycle is necessary for the O2 reduction to H2O2 (Figure 21a). From these observations, the authors concluded that O2 binding to the diprotonated form of 18 (H2TPP

• ) via NH+···O2 hydrogen bonds initiated the ORR, whereas an increase in the HTB concentration inhibited the ORR by blocking NH+ binding sites for O2. Further, the role of the proton source on ORR was confirmed by testing a stronger acid, TFA: in this case, the O2 reduction rate is decreased to almost

Cyclodextrin-based rotaxanes for polymer materials: challenge on simultaneous realization of inexpensive production and defined structures

• Yosuke Akae

Beilstein J. Org. Chem. 2024, 20, 3026–3049, doi:10.3762/bjoc.20.252

• = 20,000), revealing that the average number of penetrated CDs could be controlled from 3 to 125 (theoretical maximum was 227) by adjusting the concentration ratio of α-CD to PEG, the reaction temperature, and the end-capping method (Scheme 4B) [65]. Concurrently, in 2007, Jouini and co-workers reported

• of 8 shaped two CD rings movable along the polymer main chains. Thus, the applied stress can be distributed to the entire material by the movement of the crosslinking points to avoid a stress concentration, leading to a higher toughness than the conventional materials. Since a lot of existing review

4,6-Diaryl-5,5-difluoro-1,3-dioxanes as chiral dopants for liquid crystal compositions

• Maurice Médebielle,
• Peer Kirsch,
• Jérémy Merad,
• Carolina von Essen,
• Clemens Kühn and
• Andreas Ruhl

Beilstein J. Org. Chem. 2024, 20, 2940–2945, doi:10.3762/bjoc.20.246

• from neat chiral mesogens, or through the addition of a chiral dopant to an achiral nematic liquid crystal [5][6]. The ability of the dopant to induce chirality in the nematic phase is defined as the helical twisting power [HTP; β = (pc)−1; with p the helical pitch and c the molar concentration]. The

• most common type of liquid crystal displays (LCD) is based on the so-called twisted nematic (TN) mode and requires only a quite small HTP (typically around 10–15 µm−1) with a low dopant concentration (around 0.1%) [1][2][7]. However, there are other display modes, such as super-twisted nematic (STN

N-Glycosides of indigo, indirubin, and isoindigo: blue, red, and yellow sugars and their cancerostatic activity

• Peter Langer

Beilstein J. Org. Chem. 2024, 20, 2840–2869, doi:10.3762/bjoc.20.240

• cytotoxic activity against melanoma and squamous cell carcinoma cells, lung cancer and glioblastoma cells [30]. It was shown in a WST-1 assay that these compounds exhibit a concentration-dependent inhibition of the metabolic activity of A375 and A431 cells, while the non-glycosylated derivative 34 proved to

• be inactive. The activities of β-33b and 34 on the cell viability was independently studied by using crystal violet as a dye for viable cells following a 48 h incubation of A375 melanoma cells and A431 squamous carcinoma cells. Interestingly, a concentration-dependent cytotoxicity was again observed

• inhibition of colony formation were observed. Likewise, a concentration-dependent decrease of both the basal and ATP-linked oxygen consumption rate and of the capacity of oxidative respiration were observed at the mitochondrial level in the presence of compound β-33b. In addition, the morphology of the

Investigation of a bimetallic terbium(III)/copper(II) chemosensor for the detection of aqueous hydrogen sulfide

• Parvathy Mini,
• Michael R. Grace,
• Genevieve H. Dennison and
• Kellie L. Tuck

Beilstein J. Org. Chem. 2024, 20, 2818–2826, doi:10.3762/bjoc.20.237

• -DPA)3]3−, Tb.1 exhibited limited solubility in water, becoming insoluble at concentrations exceeding 100 μM. Therefore, a 1 mM stock solution of Tb.1 was prepared in DMSO, with the final concentration of DMSO in analytical solutions kept at ≤5%. Initial luminescence analysis of a 5 μM solution of Tb.1

• concentration range of 0–15 μM (R2 = 0.974, Figure 4). The linear increase in luminescence, compared to the “lag-phase” observed in HEPES buffer, can be attributed to the Tris-HCl buffer forming a complex with Cu2+ ions, a phenomenon only weakly observed with HEPES buffer [19][20]. We hypothesize that using

• each addition. In situ preparation of the [Tb.1·3Cu]3+ sensor. Solutions of 5 μM [Tb.1·3Cu]3+ were prepared by combining a DMSO stock solution of Tb.1 (100 μM) with 1 mM Cu(NO3)2·5H2O(aq). Solutions were then diluted with the appropriate amount of buffer (final concentration 10 mM Tris–HCl or 10 mM

Mechanochemical difluoromethylations of ketones

• Jinbo Ke,
• Pit van Bonn and
• Carsten Bolm

Beilstein J. Org. Chem. 2024, 20, 2799–2805, doi:10.3762/bjoc.20.235

• absorption of mechanical energy and they are influenced by several factors, including the lack of solvation, changes in morphology and rheology of the reaction mixtures during the milling, and variations in concentration and dielectric environment. Consequently, an increased reactivity can be achieved

• difluorocarbene typically requires harsh conditions and involves toxic precursors, alongside with the risk of dimerization to tetrafluoroethylene [31]. Although this dimerization can be mitigated by controlling the concentration and reaction environment, as longer half-lives are observed for difluorocarbenes in

C–C Coupling in sterically demanding porphyrin environments

• Liam Cribbin,
• Brendan Twamley,
• Nicolae Buga,
• John E. O’ Brien,
• Raphael Bühler,
• Roland A. Fischer and
• Mathias O. Senge

Beilstein J. Org. Chem. 2024, 20, 2784–2798, doi:10.3762/bjoc.20.234

• of lower yields experienced for porphyrins 41, 42, and 43 of 4%, 30%, and 10%, respectively. Overall, a general trend of decreased yield moving from the para- to meta-position was observed, also a general increased catalyst concentration was needed for reactivity to occur at the meta-position. Lastly

Interaction of a pyrene derivative with cationic [60]fullerene in phospholipid membranes and its effects on photodynamic actions

• Hayato Takagi,
• Çetin Çelik,
• Ryosuke Fukuda,
• Qi Guo,
• Tomohiro Higashino,
• Hiroshi Imahori,
• Yoko Yamakoshi and
• Tatsuya Murakami

Beilstein J. Org. Chem. 2024, 20, 2732–2738, doi:10.3762/bjoc.20.231

• Figure 4a, the intensity decreased upon increasing the concentration of the catC60 in the liposomes, showing the quench of PyBA fluorescence by catC60, presumably by interacting in the liposome membrane. The incomplete quenching after the addition of PyBA at a concentration comparable to that of catC60

• °C to prepare the lipid films. The lipid films were then dried overnight in vacuo. Then, the films were hydrated with PBS(–) (137 mM NaCl, 2.68 mM KCl, 8.1 mM Na2HPO4, 1.47 mM KH2PO4) so that the theoretical value of DMPC concentration was 3 mg/mL, and the resulting suspension was sonicated at 30 °C

• spectrometer (Shimadzu Corporation, Kyoto, Japan). Fluorescence measurement DMPC liposomes containing 0, 5.4, or 54 µM catC60 were mixed with PyBA (final concentration of 50 µM) in PBS(–), and the mixture was dialysed against 3 L PBS for 2 h to remove free PyBA. Fluorescence spectra were measured using an RF

Synthesis of fluoroalkenes and fluoroenynes via cross-coupling reactions using novel multihalogenated vinyl ethers

• Yukiko Karuo,
• Keita Hirata,
• Atsushi Tarui,
• Kazuyuki Sato,
• Kentaro Kawai and
• Masaaki Omote

Beilstein J. Org. Chem. 2024, 20, 2691–2703, doi:10.3762/bjoc.20.226

• , Table 2, we selected bis(triphenylphosphine)palladium as an effective catalyst, but increase of 5a to 1.5 equiv did not improve the reaction yield. Diluting the reaction concentration from 0.83 M to 0.2 M achieved to give 3a in a 63% yield (Table 2, entry 12). Increasing the amount of palladium catalyst

Photoluminescence color-tuning with polymer-dispersed fluorescent films containing two fluorinated diphenylacetylene-type fluorophores

• Kazuki Kobayashi,
• Shigeyuki Yamada,
• Motohiro Yasui and
• Tsutomu Konno

Beilstein J. Org. Chem. 2024, 20, 2682–2690, doi:10.3762/bjoc.20.225

• from the ideal white point. Conclusion In conclusion, we prepared PMMA dispersion films with a single component of fluorinated diphenylacetylene or a blend of two fluorinated diphenylacetylenes at a concentration of 1 wt % and investigated their PL behavior in detail. Among the fluorinated

Transition-metal-free decarbonylation–oxidation of 3-arylbenzofuran-2(3H)-ones: access to 2-hydroxybenzophenones

• Bhaskar B. Dhotare,
• Seema V. Kanojia,
• Chahna K. Sakhiya,
• Amey Wadawale and
• Dibakar Goswami

Beilstein J. Org. Chem. 2024, 20, 2655–2667, doi:10.3762/bjoc.20.223

• -absorption studies UV–vis absorbance spectra of the 5-substituted-2-hydroxybenzophenones 4aa–ka were recorded in triplicates at room temperature (298 K) in ethanol at a concentration of 40 µM, in the range of 225–500 nm at 1 nm intervals [11]. The obtained data were corrected using calibration methods with

• ethanol as a blank. The critical wavelength (λc) and UVA/UVB ratio were calculated using Equation 1 and Equation 2, respectively, as shown below. Determination of SPF (sun protection factor) An ethanolic solution of the compounds 4aa–ka was prepared at a concentration of 200 μg/mL. The UV–vis absorption

Applications of microscopy and small angle scattering techniques for the characterisation of supramolecular gels

• Connor R. M. MacDonald and
• Emily R. Draper

Beilstein J. Org. Chem. 2024, 20, 2608–2634, doi:10.3762/bjoc.20.220

• to assemble NFs. The self-sorting of NFs decreases the concentration of NGs, increasing the relative concentration of CGs, allowing a higher critical assembly concentration of the CGs (arising from electrostatic repulsions between the CGs) to be reached, leading to the co-assembly of CFs. Not only

• , the bulk gel (which may not be the same as the surface) is inaccessible and cannot be characterised. AFM has the advantage of allowing for the measurement of hydrated samples, and therefore does not suffer from drying artefacts. Since hydrogels are mainly made of water and low concentration hydrogels

• the range of hierarchical assemblies [32]. Another significant concern posed by blotting is the brief introduction of an air–water interface which can lead to preferential organisation of particles, as well as unpredictable changes in local concentration on the TEM grid [41]. To overcome such

Synthesis and cytotoxicity studies of novel N-arylbenzo[h]quinazolin-2-amines

• Battini Veeraiah,
• Kishore Ramineni,
• Dabbugoddu Brahmaiah,
• Nangunoori Sampath Kumar,
• Hélène Solhi,
• Rémy Le Guevel,
• Chada Raji Reddy,
• Frédéric Justaud and
• René Grée

Beilstein J. Org. Chem. 2024, 20, 2592–2598, doi:10.3762/bjoc.20.218

• the meta-methoxy 4f and ortho-fluoro 4h show significant toxicity only on Caco-2 (IC50 4.3 and 4.6 μM, respectively). Further, the para-methyl compound 4d acts on HCT-116 only (IC50 5 μM). On the other hand, all molecules exhibited no effect on normal human fibroblasts at the highest concentration

• assays: primary screen (unique concentration) and secondary screen (IC50) Both studies have been performed following the protocols described in a previous paper, see ref. [2]. Aminoquinazolines and our new target molecules. Target molecules 4 prepared with the yields for the last step. Synthesis of the

Machine learning-guided strategies for reaction conditions design and optimization

• Lung-Yi Chen and
• Yi-Pei Li

Beilstein J. Org. Chem. 2024, 20, 2476–2492, doi:10.3762/bjoc.20.212

• acid–base salts, and continuous variables, such as temperature, pressure, substrate concentration, and residence time. Regression prediction models are then built for these reaction parameters and target objectives by collecting experimental data and conducting statistical analysis. Many reaction

Homogeneous continuous flow nitration of O-methylisouronium sulfate and its optimization by kinetic modeling

• Jiapeng Guo,
• Weike Su and
• An Su

Beilstein J. Org. Chem. 2024, 20, 2408–2420, doi:10.3762/bjoc.20.205

• 94%, initial reactant concentration of 0.5 mol/L, reaction temperature of 40 °C, molar ratio of reactants at 4.4:1, and a residence time of 12.36 minutes. Keywords: continuous flow; kinetic modeling; nitration; reaction optimization; static mixer; Introduction The demand for high-quality

• thermal dissociation and oligomerization, the residence time and temperature were designed rationally to improve the yield of cyclopentadiene. Since NO2+ is the actual substance that plays a role in the nitrification process [16], kinetic modeling based on the concentration of NO2+ is essential for the

• is critical in ensuring the smooth progression of the nitration reaction within a homogeneous system. Given the strongly exothermic nature of this reaction, an excessively high concentration of IO can lead to an overproduction of heat, thereby elevating the associated risks. In contrast, a

Synthesis, electrochemical properties, and antioxidant activity of sterically hindered catechols with 1,3,4-oxadiazole, 1,2,4-triazole, thiazole or pyridine fragments

• Daria A. Burmistrova,
• Andrey Galustyan,
• Nadezhda P. Pomortseva,
• Kristina D. Pashaeva,
• Maxim V. Arsenyev,
• Oleg P. Demidov,
• Mikhail A. Kiskin,
• Andrey I. Poddel’sky,
• Nadezhda T. Berberova and
• Ivan V. Smolyaninov

Beilstein J. Org. Chem. 2024, 20, 2378–2391, doi:10.3762/bjoc.20.202

• heterocycle substitute at the sulfur atom [49][50][54]. Non-enzymatic process of the rat (Wistar) liver homogenate lipid peroxidation (LP) in the presence of additives of target compounds 1–9 was studied in vitro. The concentration of the carbonyl compounds forming in the reaction of the lipid peroxidation

• was determined by the accumulation of a colored complex with thiobarbituric acid (TBARS) (Figure 9). A decrease in TBARS concentration was observed in the presence of all tested compounds which indicates their antioxidant effect during incubation time. At the initial stage (3 h), catechol thione 8

• (control) during the incubation for 3, 24, and 48 hours (concentration of compounds in the reaction medium is 0.1 mM). The results are expressed as mean ± standard deviation (* p < 0.001; ** p < 0.01; ***p < 0.05). Synthesis of catechol-containing compounds 1–9. Electrochemical transformations of compounds

Improved deconvolution of natural products’ protein targets using diagnostic ions from chemical proteomics linkers

• Andreas Wiest and
• Pavel Kielkowski

Beilstein J. Org. Chem. 2024, 20, 2323–2341, doi:10.3762/bjoc.20.199

• alkyne probe from the CuAAC reaction mixture or by increasing the concentration of the reducing agent such as tris(2-carboxyethyl)phosphine (TCEP). The reversed chemical proteomics approach in which the azide probe and alkyne tag are used suffers from similar unspecific reactivity of the terminal alkyne

• with free thiols, including the protein cysteines reacting to thioalkyne conjugates [66][67]. This is caused by the relatively high concentration of the alkyne tag which is used to accelerate the reaction. The chemical proteomics workflows can be differentiated based on their read out, which can be

• probe–protein interactions are not detected because of the denaturing conditions of the SDS-PAGE. Alternatively, the fidelity of the probe labeling can be tested by a competition experiment, in which the parent compound lacking a bioorthogonal tag is used at increasing concentration to outcompete the

Stereoselective mechanochemical synthesis of thiomalonate Michael adducts via iminium catalysis by chiral primary amines

• Michał Błauciak,
• Dominika Andrzejczyk,
• Błażej Dziuk and
• Rafał Kowalczyk

Beilstein J. Org. Chem. 2024, 20, 2313–2322, doi:10.3762/bjoc.20.198

• aim to decrease the time along with the generation of a product with an acceptable yield, we decided to perform the reaction under ball milling conditions reasoning that choice by limiting the solvent, increasing the concentration of both reagents and catalyst accompanying with the efficient mixing

• Michael product. We were sincerely interested in shortening the reaction time. This could be achieved by conducting the reaction under conditions of efficient mixing, increasing substrate concentration without solvents, and utilizing transient but repeatable pressure and temperature increases. These

Catalysing (organo-)catalysis: Trends in the application of machine learning to enantioselective organocatalysis

• Stefan P. Schmid,
• Leon Schlosser,
• Frank Glorius and
• Kjell Jorner

Beilstein J. Org. Chem. 2024, 20, 2280–2304, doi:10.3762/bjoc.20.196

Cell-free protein synthesis with technical additives – expanding the parameter space of in vitro gene expression

• Tabea Bartsch,
• Stephan Lütz and
• Katrin Rosenthal

Beilstein J. Org. Chem. 2024, 20, 2242–2253, doi:10.3762/bjoc.20.192

• /ethylene glycol (EG), and choline chloride/glycerol) were chosen as additives to vary the viscosity, ion concentration, amount of macromolecules, and osmolarity in CFPS. The calculated values for the properties of the CFPS system with polymers and DES added at different concentrations are shown in Table 1

• molecular weight of PEG-8000 (8000 g/mol) is below the typical definition of a macromolecule (10,000 g/mol [26]), it is conventionally considered an artificial crowding agent [25] and was included in the calculation of macromolecules. The concentration of inorganic ions in the CFPS system, calculated from

• the magnesium and potassium glutamate concentration, is 140 mM, which is less than half the concentration reported for the cellular environment. The cytoplasmic osmolarity of about 600 mOsm [16] is 50% higher than that calculated for CFPS. Taking into account all defined components, the water content