Synthesis, optical and electrochemical properties of (D–π)₂-type and (D–π)₂Ph-type fluorescent dyes

• Kosuke Takemura,
• Kazuki Ohira,
• Taiki Higashino,
• Keiichi Imato and
• Yousuke Ooyama

Beilstein J. Org. Chem. 2022, 18, 1047–1054, doi:10.3762/bjoc.18.106

• evaluated to be 0.28 V for OTK-2 and 0.35 V for OTT-2. Therefore, the E1/2ox for OTK-2 with the (D–π)2Ph-type structure is cathodically shifted by 0.07 V, compared with that for OTT-2 with the (D–π)2-type structure. Furthermore, we investigated the diffusion-controlled process form CV at different scan

• negligible change during 20 cycles at a scan rate of 100 mV s−1, indicating diffusion control and good reversibility of the oxidation process (Figures S2b,c and S3b,c, Supporting Information File 1). The highest occupied molecular orbital (HOMO) energy level versus vacuum level was estimated from the E1/2ox

Cholyl 1,3,4-oxadiazole hybrid compounds: design, synthesis and antimicrobial assessment

• Anas J. Rasras,
• Mohamed El-Naggar,
• Nesreen A. Safwat and
• Raed A. Al-Qawasmeh

Beilstein J. Org. Chem. 2022, 18, 631–638, doi:10.3762/bjoc.18.63

• against the pathogenic fungal strains Aspergillus fumigatus and Candida albicans. The sensitivity of the organisms was assayed against the activity of tested compounds solutions (at 10 mg/mL concentration) using a modified agar well diffusion method with determination of the inhibition zone diameter in mm

• inhibition zone diameter using the agar well diffusion method. The structure–activity relationship (SAR) elaborated that piperazines with aliphatic groups on the nitrogen atom are more active than those with aromatic substituents against the fungus C. albicans. On the other hand, compounds comprising

• compounds 4a–v. In vitro antimicrobial activities of the synthesized compounds tested at 10 mg/mL by modified well diffusion agar method and expressed as mean inhibition zone diameter (mm). Minimum inhibitory concentrations (MIC, µg/mL) of the synthesized compounds determined by microdilution method

Shift of the reaction equilibrium at high pressure in the continuous synthesis of neuraminic acid

• Jannis A. Reich,
• Miriam Aßmann,
• Kristin Hölting,
• Paul Bubenheim,
• Jürgen Kuballa and
• Andreas Liese

Beilstein J. Org. Chem. 2022, 18, 567–579, doi:10.3762/bjoc.18.59

• desired pressure (usually 1.7–2 mL/min). Another advantage is the reduction of film diffusion on the carriers. A key advantage of this setup is that sampling and reaction at high pressure can occur simultaneously and progress curves can be measured in one reactor. Prior publications investigating high

• regression, the error given corresponds to the 95% confidence interval. All particles were pestled to remove potential diffusion limitations. All experiments were conducted at 40 °C and in potassium phosphate buffer. Since the pump is intended for UHPLC applications, a mixing chamber was installed for up to

Synthesis of piperidine and pyrrolidine derivatives by electroreductive cyclization of imine with terminal dihaloalkanes in a flow microreactor

• Yuki Naito,
• Naoki Shida and
• Mahito Atobe

Beilstein J. Org. Chem. 2022, 18, 350–359, doi:10.3762/bjoc.18.39

• time, extremely fast molecular diffusion, and expelling the reaction product to avoid over-oxidation or over-reduction. We have previously reported the electrochemical carboxylation of several imines in a flow microreactor to afford the corresponding α-amino acids in good to moderate yields [33][34][35

DABCO-promoted photocatalytic C–H functionalization of aldehydes

• Bruno Maia da Silva Santos,
• Mariana dos Santos Dupim,
• Cauê Paula de Souza,
• Thiago Messias Cardozo and
• Fernanda Gadini Finelli

Beilstein J. Org. Chem. 2021, 17, 2959–2967, doi:10.3762/bjoc.17.205

• reaction potential energy surface (PES). All procedures resulted in reaction paths with no evidence of any significant barrier, indicating that HAT steps with quinuclidine should proceed at faster rates than with DABCO, possibly at the diffusion limit. (We refer the reader to chapter 8 of Supporting

Cryogels: recent applications in 3D-bioprinting, injectable cryogels, drug delivery, and wound healing

• Luke O. Jones,
• Leah Williams,
• Tasmin Boam,
• Martin Kalmet,
• Chidubem Oguike and
• Fiona L. Hatton

Beilstein J. Org. Chem. 2021, 17, 2553–2569, doi:10.3762/bjoc.17.171

• to its low toxicity and to control the release of compounds stored in the porous structure through one of four methods: diffusion-controlled, swelling-controlled, erosion-controlled, and stimulus-controlled [54]. A study by Koshy et al. reported a methacrylated gelatin (GelMA) cryogel implanted by

• both cryogels and ceramics into a mould, and a physical cross-linker was used to realise the drug theophylline after stimuli had been achieved. Due to the layer system, drug release could occur without diffusion of the subsequent layers, controlling the speed of the release in the ceramic cryogel. In

(Phenylamino)pyrimidine-1,2,3-triazole derivatives as analogs of imatinib: searching for novel compounds against chronic myeloid leukemia

• Luiz Claudio Ferreira Pimentel,
• Lucas Villas Boas Hoelz,
• Henayle Fernandes Canzian,
• Frederico Silva Castelo Branco,
• Andressa Paula de Oliveira,
• Vinicius Rangel Campos,
• Floriano Paes Silva Júnior,
• Rafael Ferreira Dantas,
• Jackson Antônio Lamounier Camargos Resende,
• Anna Claudia Cunha,
• Nubia Boechat and
• Mônica Macedo Bastos

Beilstein J. Org. Chem. 2021, 17, 2260–2269, doi:10.3762/bjoc.17.144

• in Figure 3 [32], may have better passive diffusion through the membrane of the target cell, increasing its concentration in the intracellular medium and consequently its activity. In relation to CC50 values of the compounds selected for the cell viability test (2c, 2d, and 2g), all were less potent

Constrained thermoresponsive polymers – new insights into fundamentals and applications

• Patricia Flemming,
• Alexander S. Münch,
• Andreas Fery and
• Petra Uhlmann

Beilstein J. Org. Chem. 2021, 17, 2123–2163, doi:10.3762/bjoc.17.138

• low viscosity, high density of polymer segments and functional groups as well as a smaller hydrodynamic radius and larger diffusion coefficient compared to linear polymer chains in solution. Amphiphilic AB-type copolymers spontaneously form micelle structures above a critical concentration by self

Progress and challenges in the synthesis of sequence controlled polysaccharides

• Giulio Fittolani,
• Theodore Tyrikos-Ergas,
• Denisa Vargová,
• Manishkumar A. Chaube and
• Martina Delbianco

Beilstein J. Org. Chem. 2021, 17, 1981–2025, doi:10.3762/bjoc.17.129

• of the self-assembly of cellulose chains at the active site of the enzyme suggested that diffusion of the aggregated molecules and the monomers around the active center dictates the DP that can be obtained by enzymatic polymerization [70][71]. This could be the reason causing enzymatic reactions to

Development of N-F fluorinating agents and their fluorinations: Historical perspective

• Teruo Umemoto,
• Yuhao Yang and
• Gerald B. Hammond

Beilstein J. Org. Chem. 2021, 17, 1752–1813, doi:10.3762/bjoc.17.123

Co-crystallization of an organic solid and a tetraaryladamantane at room temperature

• Fabian Rami,
• Jan Nowak,
• Felix Krupp,
• Wolfgang Frey and
• Clemens Richert

Beilstein J. Org. Chem. 2021, 17, 1476–1480, doi:10.3762/bjoc.17.103

• evaporation or diffusion. The implications for generating other co-crystals of two solids are briefly discussed. Keywords: adamantanes; crystallization; organic solids; structure elucidation; X-ray crystallography; Introduction Obtaining a crystal suitable for X-ray crystallography can be a challenge for

• instead. It is often unclear whether crystallization is too slow or too unfavorable to occur. There are several approaches to overcome the reluctance of some organic compounds to crystallize. Among them are the crystallization of small molecules at very low temperatures [5][6][7], and the diffusion into a

• conventional approach, using dichloromethane as solvent and slow evaporation or diffusion of a poor solvent into the dichloromethane solution to obtain co-crystals. Two such solvent-based crystallization runs produced the co-crystal structures shown in Figure 2. For TDA, 5 mg of the chaperone and 1 mg of

Double-headed nucleosides: Synthesis and applications

• Vineet Verma,
• Jyotirmoy Maity,
• Vipin K. Maikhuri,
• Ritika Sharma,
• Himal K. Ganguly and
• Ashok K. Prasad

Beilstein J. Org. Chem. 2021, 17, 1392–1439, doi:10.3762/bjoc.17.98

Photoinduced post-modification of graphitic carbon nitride-embedded hydrogels: synthesis of 'hydrophobic hydrogels' and pore substructuring

• Cansu Esen and
• Baris Kumru

Beilstein J. Org. Chem. 2021, 17, 1323–1334, doi:10.3762/bjoc.17.92

• take the advantage of entrapped water that might provide the opportunity to control the water retention. Unfortunately, during the photomodification, diffusion of vTA molecules has driven the water molecules outside the network. Despite this fact, the wet-modified sample resulted in a fair water

A comprehensive review of flow chemistry techniques tailored to the flavours and fragrances industries

• Guido Gambacorta,
• James S. Sharley and
• Ian R. Baxendale

Beilstein J. Org. Chem. 2021, 17, 1181–1312, doi:10.3762/bjoc.17.90

Structural effects of meso-halogenation on porphyrins

• Keith J. Flanagan,
• Maximilian Paradiz Dominguez,
• Zoi Melissari,
• Hans-Georg Eckhardt,
• René M. Williams,
• Dáire Gibbons,
• Caroline Prior,
• Gemma M. Locke,
• Alina Meindl,
• Aoife A. Ryan and
• Mathias O. Senge

Beilstein J. Org. Chem. 2021, 17, 1149–1170, doi:10.3762/bjoc.17.88

• Dimé et al. [58]. Crystallography Crystals were grown using techniques following the protocol developed by Hope [59]. Crystals were either grown by allowing the solvent to slowly evaporate over time or by a liquid:liquid diffusion process. The crystal was mounted on a MiTeGen MicroMount and single

Enhanced target cell specificity and uptake of lipid nanoparticles using RNA aptamers and peptides

• Roslyn M. Ray,
• Anders Højgaard Hansen,
• Maria Taskova,
• Bernhard Jandl,
• Jonas Hansen,
• Citra Soemardy,
• Kevin V. Morris and
• Kira Astakhova

Beilstein J. Org. Chem. 2021, 17, 891–907, doi:10.3762/bjoc.17.75

• cells (Figure 2B and Supporting Information File 1, Figure S4). Passive diffusion of the LNPs with the G-3 aptamer alone through a transwell insert without hCMEC/D3 cells appears to show higher uptake in the HeLa cell line but lower uptake in the TZM-bl cell line in comparison to the transwell insert

Synthetic reactions driven by electron-donor–acceptor (EDA) complexes

• Zhonglie Yang,
• Yutong Liu,
• Kun Cao,
• Xiaobin Zhang,
• Hezhong Jiang and
• Jiahong Li

Beilstein J. Org. Chem. 2021, 17, 771–799, doi:10.3762/bjoc.17.67

• electron transfer and forming a pair of radical ions trapped in the solvent cage. The pair of radical ions escapes the solvent cage by diffusion to give radical ions, which could initiate chemical reactions or reverse electron transfer (Scheme 1) [6]. The continuously increasing demand for sustainable

Valorisation of plastic waste via metal-catalysed depolymerisation

• Francesca Liguori,
• Carmen Moreno-Marrodán and
• Pierluigi Barbaro

Beilstein J. Org. Chem. 2021, 17, 589–621, doi:10.3762/bjoc.17.53

• ][10]. Plastic materials are ubiquitous in our everyday life, which accounts for a global production of plastics of around 360 million tons in 2018 [11], of which more than 60% are disposed [12][13]. As a consequence, pollution from plastics is impressive, resulting in the diffusion of microplastics

Synthesis and physicochemical evaluation of fluorinated lipopeptide precursors of ligands for microbubble targeting

• Masayori Hagimori,
• Estefanía E. Mendoza-Ortega and
• Marie Pierre Krafft

Beilstein J. Org. Chem. 2021, 17, 511–518, doi:10.3762/bjoc.17.45

• faster diffusion of the former lipopeptides to the interface and by their larger value of πeq, hence a lower surface tension at the bubble surface. The enhanced MB stability over time and the fact that the half-life increases with fluorocarbon chain length support the view that stabilizing interactions

• -lives are obtained with the hydrocarbon analog. Our results establish that a fluorination of the precursors of targeting ligand–peptide conjugates can considerably facilitate microbubble generation due to faster diffusion to the air/water interface, and augment their stability through interfacial

Biochemistry of fluoroprolines: the prospect of making fluorine a bioelement

• Vladimir Kubyshkin,
• Rebecca Davis and
• Nediljko Budisa

Beilstein J. Org. Chem. 2021, 17, 439–460, doi:10.3762/bjoc.17.40

Au(III) complexes with tetradentate-cyclam-based ligands

• Ann Christin Reiersølmoen,
• Thomas N. Solvi and
• Anne Fiksdahl

Beilstein J. Org. Chem. 2021, 17, 186–192, doi:10.3762/bjoc.17.18

• , due to sample decomposition. Attempts to obtain crystals for X-ray analysis by slow diffusion of n-pentane into a DCM solution of the complexes were unsuccessful. Catalytic activity For evaluation of the catalytic ability of the new Au(III) complexes, alkyne carboalkoxylation [47][48] and

Multiswitchable photoacid–hydroxyflavylium–polyelectrolyte nano-assemblies

• Alexander Zika and
• Franziska Gröhn

Beilstein J. Org. Chem. 2021, 17, 166–185, doi:10.3762/bjoc.17.17

• fully revert back when bound in the assemblies. To investigate how these differences in molecular building block structure affect the assembly nanoscale size and structure, dynamic and static light scattering (DLS, SLS) were performed. DLS measures the intensity fluctuations caused by the diffusion of

• electric field autocorrelation function g1(τ). By a regularized inverse Laplace transformation, the electric field autocorrelation function g1(τ) was transformed into the distribution of relaxation times A(τ). The apparent diffusion coefficients Dapp were calculated by Equation 3 The diffusion coefficients

Control over size, shape, and photonics of self-assembled organic nanocrystals

• Chen Shahar,
• Yaron Tidhar,
• Yunmin Jung,
• Haim Weissman,
• Sidney R. Cohen,
• Ronit Bitton,
• Iddo Pinkas,
• Gilad Haran and
• Boris Rybtchinski

Beilstein J. Org. Chem. 2021, 17, 42–51, doi:10.3762/bjoc.17.5

• ). Convenient control over the structure and function of organic nanocrystals can enhance their utility in new and developed technologies. Keywords: aromatic amphiphiles; exciton diffusion; organic nanocrystals; perylene diimides; self-assembly; Introduction Semiconductor and metal nanoparticles exhibit size

• nanocrystals with a tunable aspect ratio. These systems are quite uniform and exhibit morphology-dependent photonics: strikingly, divergent exciton diffusion properties as a function of the shape. Results and Discussion Following our interest in the self-assembly of PDI derivatives, we employed compound 1, a

• sample was measured, showing exciton dynamics very similar to the original 5% THF sample (Table 1 and Figure S9B, Supporting Information File 1). In order to estimate the exciton diffusion coefficient and the diffusion length, we used an analysis method employed in our previous work [36] and based on a

Controlled decomposition of SF₆ by electrochemical reduction

• Sébastien Bouvet,
• Bruce Pégot,
• Stéphane Sengmany,
• Erwan Le Gall,
• Eric Léonel,
• Anne-Marie Goncalves and
• Emmanuel Magnier

Beilstein J. Org. Chem. 2020, 16, 2948–2953, doi:10.3762/bjoc.16.244

• to a large decrease of the capacitive current and avoids IR drop effects. The array of Pt microdiscs offers the advantage of summing the current intensity of each microelectrode, thus increasing the sensitivity of the resulting current [25]. Whereas a planar diffusion is observed onto classical

• electrode (size >0.1 cm2), a hemispherical diffusion is expected with a microdisc electrode due to the contribution of the current diffusion by edge effects. The mass transport regime is then drastically modified on microdisc electrodes and can be adjusted in accordance with the polarization time by

• current of diffusion (id), which is directly proportional to the bulk concentration of the electroactive substance (C∞), its diffusion coefficient in the solvent (D), the number of electrons exchanged in the electrochemical process (n), and the radius of the microelecrode (r) and F the Faraday constant

Particle size effect in the mechanically assisted synthesis of β-cyclodextrin mesitylene sulfonate

• Stéphane Menuel,
• Sébastien Saitzek,
• Eric Monflier and
• Frédéric Hapiot

Beilstein J. Org. Chem. 2020, 16, 2598–2606, doi:10.3762/bjoc.16.211

• study, we found that the reactivity depended more upon diffusion phenomena in the crystalline parts of the material than on the increase in the surface area of the CD particles resulting from grinding. Keywords: beta-cyclodextrin; chemoselectivity; grinding; mechanosynthesis; reactivity; Introduction

• ), the ratio of mono-substituted β-CDMts to poly-substituted β-CDMts derivatives increased over time, as depicted in Figure 7. This result is probably due to the homogeneous diffusion of KOH within the solid mixture facilitating the deprotonation of a larger number of β-CDs rather than only a few of them

• (Supporting Information File 1, Table S3). Accordingly, it appeared that different models seemed appropriate to picture the reaction kinetics, meaning that the process probably results from various contributions, including nucleation, geometrical contraction, diffusion and reaction-order models. However, one