Cs₂CO₃-Promoted reaction of tertiary bromopropargylic alcohols and phenols in DMF: a novel approach to α-phenoxyketones

• Ol'ga G. Volostnykh,
• Olesya A. Shemyakina,
• Anton V. Stepanov and
• Igor' A. Ushakov

Beilstein J. Org. Chem. 2022, 18, 420–428, doi:10.3762/bjoc.18.44

• performed on a Flash 2000 elemental analyzer. Melting points were determined using a Kofler micro hot stage apparatus. Mass spectra were recorded on a GCMS-QP5050A spectrometer made by Shimadzu Company. Chromatographic column parameters were as follows: SPBТМ-5, length 60 m, internal diameter 0.25 mm

Unsaturated fatty acids and a prenylated tryptophan derivative from a rare actinomycete of the genus Couchioplanes

• Shun Saito,
• Kanji Indo,
• Naoya Oku,
• Hisayuki Komaki,
• Masashi Kawasaki and
• Yasuhiro Igarashi

Beilstein J. Org. Chem. 2021, 17, 2939–2949, doi:10.3762/bjoc.17.203

• extract 0.5%, and glucose 0.2% (pH 7.3) solidified by agar 2%, was inoculated into test tubes (inner diameter, 15 mm; length 16.5 cm) each containing 5 mL of YG seed medium consisting of glucose 1% and yeast extract 1% (pH 7.0). The tubes were shaken at 260 strokes/min at 28 °C for 3 days (TC-500R

Adjusting the length of supramolecular polymer bottlebrushes by top-down approaches

• Tobias Klein,
• Franka V. Gruschwitz,
• Maren T. Kuchenbrod,
• Ivo Nischang,
• Stephanie Hoeppener and
• Johannes C. Brendel

Beilstein J. Org. Chem. 2021, 17, 2621–2628, doi:10.3762/bjoc.17.175

• Lamour et al., we estimated a similar limit length Llim upon extensive US treatment [35]. This length allows an indirect estimation of the tensile strength σ* of our fibers according to where is the radius of the cavitation bubble, is the wall velocity of the collapsing bubble, d is the fiber diameter

• cross-section [19], and 28 nm for BTP by assuming a similar stacking distance and 2 molecules per cross-section [21]. Based on a fiber diameter of 12 nm (estimated from small-angle X-ray scattering experiments) [19][20], the resulting tensile strength for both compounds was approximately 16 to 17 MPa

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

• and found that reducing the freezing temperature by 15 °C caused an average 30 μm decrease in pore size diameter [14][17]. In contrast, it has been reported that with cryogels crosslinked with glutaraldehyde, the freezing temperature does not affect the pore size [13]. An additional consideration is

Synthesis and antimicrobial activity of 1H-1,2,3-triazole and carboxylate analogues of metronidazole

• Satya Kumar Avula,
• Syed Raza Shah,
• Khdija Al-Hosni,
• Muhammad U. Anwar,
• Rene Csuk,
• Biswanath Das and
• Ahmed Al-Harrasi

Beilstein J. Org. Chem. 2021, 17, 2377–2384, doi:10.3762/bjoc.17.154

• antifungal activity of all compounds were evaluated by inhibiting the growth of Didymella sp. (Figure 7 and Table 3). The fungal colony after 7 days of control treatment was noted to be 8.6 cm in diameter. Whereas, the growth of the fungal colony was detected maximum, i.e., 8.8 ± 0.2 and 9.0 ± 0.3 cm against

• compound 2 and 3, respectively. However, compound 5e and 7c efficiently inhibited the fungal growth by limiting the colony diameter to 3 ± 0.3 and 3.1 ± 0.2 cm followed equally by compound 7b and compound 5b with 4.1 ± 0.3 and 4.6 ± 0.2 cm, respectively. Compared to control and metronidazole treatments

Post-functionalization of drug-loaded nanoparticles prepared by polymerization-induced self-assembly (PISA) with mitochondria targeting ligands

• Janina-Miriam Noy,
• Fan Chen and
• Martina Stenzel

Beilstein J. Org. Chem. 2021, 17, 2302–2314, doi:10.3762/bjoc.17.148

• attachment of TPP-COOH to the micelle variants resulted in an increase in hydrodynamic diameter from approximately 85 nm to 136 nm for the PEG micelles and from 75 nm to 138 nm for the zwitterionic counterparts. However, no major change in dispersities was detected and well-defined nanoparticles (PdI < 0.078

• subject to CC BY 4.0. Summary of the pPEGMA and pMPC block copolymers prepared by PISA at 70 °C including the hydrodynamic diameter Dh and particle size distribution PdI obtained by DLS and the drug loading content (DLC) calculated using DLC = m(PENAO)/[m(PENAO) + m(polymer)]. The table here contains the

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

An initiator- and catalyst-free hydrogel coating process for 3D printed medical-grade poly(ε-caprolactone)

• Jochen Löblein,
• Thomas Lorson,
• Miriam Komma,
• Tobias Kielholz,
• Maike Windbergs,
• Paul D. Dalton and
• Robert Luxenhofer

Beilstein J. Org. Chem. 2021, 17, 2095–2101, doi:10.3762/bjoc.17.136

• final fiber diameter. The direct-writing onto a flat collector or on a rotating/translating mandrel enables the printing of flat [11][12] or tubular [13] scaffolds, respectively. While medical-grade poly(ε-caprolactone) (PCL) is the most commonly used material for MEW, due to its favorable thermal and

• the coating of 3D printed PCL microfiber scaffolds, investigate the range of suitable parameters and characterize the change in the properties of the coated scaffolds. PCL scaffolds with a hatch spacing of either 150 µm or 500 µm were fabricated, with the fiber diameter being 12.1 ± 3.3 µm. The

Volatile emission and biosynthesis in endophytic fungi colonizing black poplar leaves

• Christin Walther,
• Pamela Baumann,
• Katrin Luck,
• Beate Rothe,
• Peter H. W. Biedermann,
• Jonathan Gershenzon,
• Tobias G. Köllner and
• Sybille B. Unsicker

Beilstein J. Org. Chem. 2021, 17, 1698–1711, doi:10.3762/bjoc.17.118

• diameter) growing on PDA. The mycelium was flash frozen in liquid nitrogen and ground using plastic pestles in 1.5 mL Eppendorf tubes. After homogenization of the mycelium, 500 µL extraction buffer (100 mM Tris HCl, pH 8; 10 mM EDTA, pH 8; 2% w/v SDS) and 100 µL proteinase K (Sigma) were added and the

• mycelium reached a diameter of 5 cm (± 0.5 cm). For each fungal species, seven replicates were used with fungus-free petri dishes with PDA medium used as blanks. Volatiles were trapped for 1 h by using four polydimethylsiloxane (PDMS) tubes. To prevent PDMS tubes from touching the mycelium, the tubes were

• (approximately 5 cm in diameter) growing on PDA using the RNeasy® Plant Mini Kit (Qiagen) according to the manufacturer’s instructions. The RNA concentration was assessed using a spectrophotometer (NanoDrop 2000c, Thermo Fisher Scientific). RNA was treated with DNase I (Thermo Fisher Scientific) prior to cDNA

Chemical approaches to discover the full potential of peptide nucleic acids in biomedical applications

• Nikita Brodyagin,
• Martins Katkevics,
• Venubabu Kotikam,
• Christopher A. Ryan and
• Eriks Rozners

Beilstein J. Org. Chem. 2021, 17, 1641–1688, doi:10.3762/bjoc.17.116

• conformation (C2′-endo), base pair inclination, and helical rise resembled B-DNA [39]. The first X-ray crystal structure of a PNA–DNA–PNA triplex revealed a previously unknown helix with a wide diameter of ≈26 Å (compared to 20 Å for A-form duplex) and a wide and deep major groove (Figure 3), given the name "P

• stabilizing interactions are better aligned. The crystal structure of a self-complementary PNA–PNA duplex was very similar to the P-form helix showing a wide helix (28 Å diameter) with a very large pitch of ≈18 base pairs per turn, compared to 10 and 11 base pairs per turn for DNA and RNA, respectively, and a

Antiviral therapy in shrimp through plant virus VLP containing VP28 dsRNA against WSSV

• Santiago Ramos-Carreño,
• Ivone Giffard-Mena,
• Jose N. Zamudio-Ocadiz,
• Alfredo Nuñez-Rivera,
• Ricardo Valencia-Yañez,
• Jaime Ruiz-Garcia,
• Maria Teresa Viana and
• Ruben D. Cadena-Nava

Beilstein J. Org. Chem. 2021, 17, 1360–1373, doi:10.3762/bjoc.17.95

• the procapsids diameter, icosahedral VLPs, and nanotubes is shown in Figure 2B. According to the Gaussian fit for each of the distributions, the average diameter of the procapsids, icosahedral VLPs, and the rods were 21, 26, and 21 nm, respectively. During the WSSV viral inoculum activation, the

• formation and CP-dsRNAi complexes (Figure 2A, images a and b). The Gaussian fit size distribution of the spherical procapsids gave an average diameter of 21.2 nm and corresponded to capsids with triangulation number T = 2. The sample’s dialysis at pH 7.2 favors the electrostatic interactions between CCMV CP

• ] that could be favorable for tube formation. The interaction of a rigid and quasi-long dsRNA molecule with the capsid protein dimers enables the elongated tubular structure formation under these experimental conditions [59]. The spherical VLPs have an average diameter of 25.8 nm corresponding to capsids

A new glance at the chemosphere of macroalgal–bacterial interactions: In situ profiling of metabolites in symbiosis by mass spectrometry

• Marine Vallet,
• Filip Kaftan,
• Veit Grabe,
• Fatemeh Ghaderiardakani,
• Simona Fenizia,
• Aleš Svatoš,
• Georg Pohnert and
• Thomas Wichard

Beilstein J. Org. Chem. 2021, 17, 1313–1322, doi:10.3762/bjoc.17.91

• following the procedure for in situ MS imaging described by Kessler et al. [19]. Briefly, algal gametes were inoculated to 10 mL medium in 9 cm diameter sterile Petri dishes with a clean and autoclaved glass slide (25 mm × 75 mm) with cavities (Paul Marienfeld, Germany) on the bottom; samples were incubated

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

• flow [118]. The condensation of a range of aromatic aldehydes with acetone were again studied, with p-anisaldehyde (23) being used for scale-up. A simple reactor design based upon Teflon® tubing (8 mm inner diameter) was used in conjunction with static mixing elements as shown in Scheme 13, allowing

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

• nm) and TEM (≈45 nm). Thus, the average sizes obtained by NTA are in agreement with the average size observed using TEM (Supporting Information File 1, Figure S2A and Table S2). Similarly, while the mean diameter of LNP B9 G-3 was found to be larger by DLS (91.9 nm) than the values reported for NTA

• , USA). Briefly, the scale was set to the scale bar on the image, and the diameter for entire nanoparticles was measured in each image. At least 3 images per LNP formulation were used to determine the size distribution of the LNPs. Data are represented as a box and whisker plot, with min and max values

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

• compared to 2D materials, thanks to a typical 8–16 nm outer diameter tubular morphology [215][216] and the potential for facile metal doping via ion-exchange of the solid support [217][218]. Lewis acid-type catalytic activity was also postulated for γ-Fe2O3 NPs, which provided BHET in 90% yield at 300 °C

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

• provokes delipidation of the interfacial film. The incorporation of the F-lipopeptides 1–3 in microbubbles with a shell of DPPC and dipalmitoylphosphatidylethanolamine-PEG2000 decreased their mean diameter and increased their stability, the best results being obtained for the C8F17-bearing lipopeptide 3

• . By contrast, the hydrocarbon lipopeptide led to microbubbles with a larger mean diameter and a significantly lower stability. Keywords: adsorption at fluid interfaces; drug delivery; microbubble targeting; molecular imaging; monolayer; perfluoroalkylated lipopeptide; solid-phase peptide synthesis

• made from DPPC alone (e.g., 1.9 ± 0.6 μm with F-lipopeptide 3 versus 2.5 ± 0.8 μm without, Figure 3a,b). Microbubbles with similar mean diameters were obtained with the two other F-lipopeptides. By contrast, the incorporation of the hydrocarbon analog 4 led to a marked increase in the mean MB diameter

Annulation of a 1,3-dithiole ring to a sterically hindered o-quinone core. Novel ditopic redox-active ligands

• Sergey V. Norkov,
• Anton V. Cherkasov,
• Andrey S. Shavyrin,
• Maxim V. Arsenyev,
• Viacheslav A. Kuropatov and
• Vladimir K. Cherkasov

Beilstein J. Org. Chem. 2021, 17, 273–282, doi:10.3762/bjoc.17.26

• electrode (2 mm diameter), platinum wire counter electrode and Ag/AgCl/KCl reference electrode. X-ray crystallography The X-ray data for 6a–d and 7–9 were collected on Rigaku OD Xcalibur (6b–d, 7, 9) and Bruker D8 Quest (6a, 8) diffractometers (Mo Kα radiation, ω-scans technique, λ = 0.71073 Å) using APEX3

Tuning the solid-state emission of liquid crystalline nitro-cyanostilbene by halogen bonding

• Subrata Nath,
• Alexander Kappelt,
• Matthias Spengler,
• Bibhisan Roy,
• Jens Voskuhl and
• Michael Giese

Beilstein J. Org. Chem. 2021, 17, 124–131, doi:10.3762/bjoc.17.13

• after one heating/cooling cycle reveal the impact of the alkoxy chain length and a significant rearrangement of the solid-state packing upon heating/cooling the sample (diameter of sample ≈ 0.8 cm). Temperature-dependent fluorescent images of NO2-C9∙∙∙F4St showing the enhancement of emission upon

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

• pump power for studying the power dependence. The pump power intensities were measured using an Ophir powermeter with a photodiode sensor in proximity to the sample. The excitation densities were calculated for a laser spot of 300 μm diameter on the sample. This diameter was measured by placing a

Semiautomated glycoproteomics data analysis workflow for maximized glycopeptide identification and reliable quantification

• Steffen Lippold,
• Arnoud H. de Ru,
• Jan Nouta,
• Peter A. van Veelen,
• Magnus Palmblad,
• Manfred Wuhrer and
• Noortje de Haan

Beilstein J. Org. Chem. 2020, 16, 3038–3051, doi:10.3762/bjoc.16.253

• -acetylneuraminic acid (NeuAc, 291.0954 Da, max. 120 s RT difference) were enabled. For each glycopeptide cluster of interest, one data point was assigned to a composition that was verified by the Byonic search. For the visualization in GlycopeptideGraphMS, the diameter of the data points and the relative abundance

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

• reduction potential of SF6. To allow its electroreduction feasibility in acetonitrile, an electrochemical analytical approach was required [24]. This crucial step was supported by sensors which are based on a micro-disc-array of platinum ultramicroelectrodes (20 µm diameter) acting as multi-probe channels

• ultramicroelectrode with a diameter of 20 µm, an array of eight Pt ultramicroelectrodes with a diameter of 20 µm and a Pt macroelectrode with a diameter of 1 mm). Platinum disk microelectrodes were made by sealing into very fine glass, one or eight platinum wires, with a diameter of 20 µm, into the same soft glass

UV resonance Raman spectroscopy of the supramolecular ligand guanidiniocarbonyl indole (GCI) with 244 nm laser excitation

• Tim Holtum,
• Vikas Kumar,
• Daniel Sebena,
• Jens Voskuhl and
• Sebastian Schlücker

Beilstein J. Org. Chem. 2020, 16, 2911–2919, doi:10.3762/bjoc.16.240

• for deep UVRR studies [24]. This closed-loop system is driven by a peristaltic pump. A half air-filled syringe acts as an upper reservoir to flatten pressure oscillations from the peristaltic pump. An injection needle with an 0.8 mm outer diameter is attached to the syringe as the output nozzle to

Enzyme-instructed morphological transition of the supramolecular assemblies of branched peptides

• Dongsik Yang,
• Hongjian He and
• Bing Xu

Beilstein J. Org. Chem. 2020, 16, 2709–2718, doi:10.3762/bjoc.16.221

• morphology changes before and after the addition of proteinase K to solutions of 1 and 2. TEM revealed the solutions of 1 and 2 (500 μM) to contain nanoparticles of 11 ± 2 nm in diameter, indicating that the acetylation at the branch affects the self-assembly of the branched peptides only slightly. Upon the

• addition of proteinase K, the nanoparticles transformed to nanofibers of 12 ± 2 nm in diameter (Figure 4). This result indicates that the branched peptides form micelles in Tris-HCl buffer, and proteinase K generates Nap-ffky from 1 or 2, resulting in the nanofibers. When the concentration of 1 or 2 was

• (5 mM), the hydrogel of 1 contains long, flexible nanofibers with a diameter of 12 ± 2 nm. Similarly, the viscous solution of 2 also consists of nanofibers with a width around 12 nm. When the concentration of 1 or 2 is at 10 mM, the addition of proteinase K also generates the nanofibers at a diameter

A heterobimetallic tetrahedron from a linear platinum(II)-bis(acetylide) metalloligand

• Matthias Hardy,
• Marianne Engeser and
• Arne Lützen

Beilstein J. Org. Chem. 2020, 16, 2701–2708, doi:10.3762/bjoc.16.220

• these two design concepts – the subcomponent self-assembly strategy and the complex-as-a-ligand approach – ensured a fast and easy synthesis of large heterobimetallic coordination cages of tetrahedral shape with a diameter of more than 3 nm as a mixture of all three possible T-, S4- and C3-symmetric

• and shape, however, DOSY NMR experiments could nicely be used to prove that all of the detected signals correspond to species of similar size with a solvodynamic diameter of 33 Å (Figure 5) and do not belong to species of a different composition. Unfortunately, despite our greatest efforts, we did not

• large (supra-)molecular entities with astonishing accuracy [55][56]. We minimized the structures of the cationic units of all possible diastereomers of cage 4 (Figure 6). From these models we could derive a theoretically expected diameter of dcalc = 31 Å that nicely corroborates the solvodynamic

Optical detection of di- and triphosphate anions with mixed monolayer-protected gold nanoparticles containing zinc(II)–dipicolylamine complexes

• Lena Reinke,
• Julia Bartl,
• Marcus Koch and
• Stefan Kubik

Beilstein J. Org. Chem. 2020, 16, 2687–2700, doi:10.3762/bjoc.16.219

• formed, the solutions either lose their color because of nanoparticle precipitation or they adopt a different color. Dispersed spherical AuNPs with a diameter of ca. 10 nm lead to intensely colored red solutions, for example, which turn purple or blue upon nanoparticle aggregation because the localized

• nanoparticles with the desired diameter of 8–10 nm and a relatively narrow size distribution [40]. This method entailed the rapid addition of a hot aqueous solution of tetrachloroauric(III) acid to aqueous sodium citrate at 100 °C. After dialysis to remove excess citrate, the resulting solution was treated with

• signals of the immobilized ligand molecules but no sharp signals, showing that the nanoparticles were not contaminated with unbound ligands or residual citrate. According to transmission electron microscopy (TEM), NPrac-1 had an average diameter of 9.1 ± 2.4 nm and a maximum of the SPR band in the UV–vis