Monitoring carbohydrate 3D structure quality with the Privateer database

• Jordan S. Dialpuri,
• Haroldas Bagdonas,
• Lucy C. Schofield,
• Phuong Thao Pham,
• Lou Holland and
• Jon Agirre

Beilstein J. Org. Chem. 2024, 20, 931–939, doi:10.3762/bjoc.20.83

• and, therefore, poorly resolved density regions, whereas in electron cryo-microscopy different conformations and compositions are averaged out during image classification and volume reconstruction [5]. Owing to these difficulties, it is not uncommon to find problematic carbohydrate structures in the

Substrate specificity of a ketosynthase domain involved in bacillaene biosynthesis

• Zhiyong Yin and
• Jeroen S. Dickschat

Beilstein J. Org. Chem. 2024, 20, 734–740, doi:10.3762/bjoc.20.67

• cooperate with the PKS “in trans” [11][12]. Notably, in B. subtilis the giant bacillaene biosynthesis machinery forms an organelle-like complex that can be observed through cryoelectron microscopy [13]. The structure elucidation of “bacillaene” through extensive NMR spectroscopic methods revealed the

Synthesis of π-conjugated polycyclic compounds by late-stage extrusion of chalcogen fragments

• Aissam Okba,
• Pablo Simón Marqués,
• Kyohei Matsuo,
• Naoki Aratani,
• Hiroko Yamada,
• Gwénaël Rapenne and
• Claire Kammerer

Beilstein J. Org. Chem. 2024, 20, 287–305, doi:10.3762/bjoc.20.30

• tip of a scanning tunneling microscope (STM) [11][34][35][36]. Owing to the subatomic resolution now available with scanning probe microscopy techniques (STM and non-contact atomic force microscopy, nc-AFM), the “precursor approach” has opened the way for in-depth structural and electronic

• ” is particularly interesting, since the as-prepared π-extended structures can undergo in-depth structural characterization and electronic investigations in situ at the single molecule scale, thanks to scanning probe microscopy and spectroscopy. The synthetic route relying on O-extrusion was thus

Perspectives on push–pull chromophores derived from click-type [2 + 2] cycloaddition–retroelectrocyclization reactions of electron-rich alkynes and electron-deficient alkenes

• Michio Yamada

Beilstein J. Org. Chem. 2024, 20, 125–154, doi:10.3762/bjoc.20.13

• through scanning tunneling microscopy [85]. For TCBDs bearing unsubstituted anilino (p-H2NC6H4–) groups, their conversion into the p-iodophenyl derivatives via the Sandmeyer reaction and subsequent post-functionalization via the Suzuki and Sonogashira coupling reactions are achieved [86]. In the reaction

Electron-beam-promoted fullerene dimerization in nanotubes: insights from DFT computations

• Laura Abella,
• Gerard Novell-Leruth,
• Josep M. Ricart,
• Josep M. Poblet and
• Antonio Rodríguez-Fortea

Beilstein J. Org. Chem. 2024, 20, 92–100, doi:10.3762/bjoc.20.10

• electron microscopy (TEM) is a technique that has been used for a long time to provide images of molecules, but also to monitor the reactions triggered by the energy transfer of the electron beam to the atoms that build the molecules. In particular, the advances in TEM as well as in methods to anchor

Optimizing reaction conditions for the light-driven hydrogen evolution in a loop photoreactor

• Pengcheng Li,
• Daniel Kowalczyk,
• Johannes Liessem,
• Mohamed M. Elnagar,
• Dariusz Mitoraj,
• Radim Beranek and
• Dirk Ziegenbalg

Beilstein J. Org. Chem. 2024, 20, 74–91, doi:10.3762/bjoc.20.9

• microscopy (SEM) at different magnifications, as shown in Figure 1a–d. The images reveal a layered structure exhibiting a rough surface with agglomerated, irregular, and dense particles. Figure 2a–e shows the elemental mapping analysis of Pt-PCN conducted using SEM-EDX. A homogeneous distribution of Pt

Preparing a liquid crystalline dispersion of carbon nanotubes with high aspect ratio

• Keiko Kojima,
• Nodoka Kosugi,
• Hirokuni Jintoku,
• Kazufumi Kobashi and
• Toshiya Okazaki

Beilstein J. Org. Chem. 2024, 20, 52–58, doi:10.3762/bjoc.20.7

• buoyancy resulting from particle porosity [22][23][27][28]. Indeed, the DWCNT agglomerates having corresponding size can be seen in the optical microscope image of the dispersion (Figure 1b). The shapes of DWCNTs in the dispersion were examined by scanning electron microscopy (SEM) and atomic force

• microscopy (AFM) (see Supporting Information File 1, Figure S2). In both images, rod-like DWCNTs were observed, while spaghetti-like agglomerates were hardly observed. The average length (L) and diameter (D) of the DWCNT samples were ≈2.9 μm and ≈2.1 nm, respectively. The L/D of the DWCNTs was 1378, which

• dispersion. The polarizing optical microscopy (POM) images exhibited alignment of the DWCNTs along the shear direction (Figure 4a,b). To estimate the order parameter, the polarized optical absorption measurement was conducted at different sample angles ranging from 0° to 90° at intervals of 10° (Figure 4c

Biphenylene-containing polycyclic conjugated compounds

• Cagatay Dengiz

Beilstein J. Org. Chem. 2023, 19, 1895–1911, doi:10.3762/bjoc.19.141

• ]. In their study, they effectively synthesized POA 87 utilizing 2,3-dibromotetracene (85) as substrate at a temperature of 430 K, employing ultra high vacuum conditions on Ag(111). Subsequent scanning tunneling microscopy (STM) analyses unveiled not only the linear POA 87 resulting from surface

Charge carrier transport in perylene-based and pyrene-based columnar liquid crystals

• Alessandro L. Alves,
• Simone V. Bernardino,
• Carlos H. Stadtlober,
• Edivandro Girotto,
• Giliandro Farias,
• Rodney M. do Nascimento,
• Sergio F. Curcio,
• Thiago Cazati,
• Marta E. R. Dotto,
• Juliana Eccher,
• Leonardo N. Furini,
• Hugo Gallardo,
• Harald Bock and
• Ivan H. Bechtold

Beilstein J. Org. Chem. 2023, 19, 1755–1765, doi:10.3762/bjoc.19.128

• positive and negative charge carrier transport of 1 and 2. The active layers of 1 or 2 were spin-coated from chloroform solutions (10 mg/mL). Scheme S1 in Supporting Information File 1 illustrates the device structure with the energy levels of the layers. Figure 5 shows atomic force microscopy (AFM) images

• order and polarized optical microscopy show small birefringent domains, indicating locally instead of macroscopic molecular alignment of the films (see Figure S2 in Supporting Information File 1). Figure 6 shows the log–log plots of the J–V experimental curves for 1 and 2 in both device structures. In

Enabling artificial photosynthesis systems with molecular recycling: A review of photo- and electrochemical methods for regenerating organic sacrificial electron donors

• Grace A. Lowe

Beilstein J. Org. Chem. 2023, 19, 1198–1215, doi:10.3762/bjoc.19.88

• microscopy [36][37]. In nature, chemical gradients and phase separation are maintained by compartmentalization in liposomes, micelles, and vesicles rather than at interfaces such as ITIES. Artificial photosynthesis systems are being designed to mimic this behavior and recently the field of artificial

pH-Responsive fluorescent supramolecular nanoparticles based on tetraphenylethylene-labelled chitosan and a six-fold carboxylated tribenzotriquinacene

• Nan Yang,
• Yi-Yan Zhu,
• Wei-Xiu Lin,
• Yi-Long Lu and
• Wen-Rong Xu

Beilstein J. Org. Chem. 2023, 19, 635–645, doi:10.3762/bjoc.19.45

• of a large number of nanoparticles. Conversely, solutions with concentrations below the CAC values did not show an apparent Tyndall effect (Figure S3 in Supporting Information File 1), which provides further support for the accuracy of the CAC values. Transmission electron microscopy (TEM) was used

Phenanthridine–pyrene conjugates as fluorescent probes for DNA/RNA and an inactive mutant of dipeptidyl peptidase enzyme

• Josipa Matić,
• Tana Tandarić,
• Marijana Radić Stojković,
• Filip Šupljika,
• Zrinka Karačić,
• Ana Tomašić Paić,
• Lucija Horvat,
• Robert Vianello and
• Lidija-Marija Tumir

Beilstein J. Org. Chem. 2023, 19, 550–565, doi:10.3762/bjoc.19.40

• exhibited a micromolar and submicromolar binding affinity for ds-polynucleotides and inactivated a mutant of dipeptidyl peptidase enzyme E451A. Confocal microscopy revealed that the conjugate with the longer linker entered the HeLa cell membranes and blue fluorescence was visualized as the dye accumulated

• cellular uptake and intracellular distribution of Phen-Py-1 in HeLa cells by TCS SP8 X confocal microscopy. The results showed that the dye entered the HeLa cell membranes fast, and after 1 hour of incubation at 1 µM concentration, blue fluorescence was visualized as the dye accumulated in the cell

• binding (∆rH). The reaction Gibbs energies (∆rG) were calculated by using the following equation: ∆rG = −RTln(Ka). The entropic contribution to the binding Gibbs energy was calculated by the equation: T∆rS = ∆rH − ∆rG. Confocal microscopy: HeLa cells were cultured and maintained in complete high glucose

CuAAC-inspired synthesis of 1,2,3-triazole-bridged porphyrin conjugates: an overview

• Dileep Kumar Singh

Beilstein J. Org. Chem. 2023, 19, 349–379, doi:10.3762/bjoc.19.29

• . These prepared porphyrin nanowires were subjected to surface microscopy and fluorescence energy transfer experiments, which elucidated their stability and resistance to disassembly. Conclusion Cu(I)-catalyzed “click chemistry” is a well-established protocol for the facile access of complexes from simple

Insight into oral amphiphilic cyclodextrin nanoparticles for colorectal cancer: comprehensive mathematical model of drug release kinetic studies and antitumoral efficacy in 3D spheroid colon tumors

• Sedat Ünal,
• Gamze Varan,
• Juan M. Benito,
• Yeşim Aktaş and
• Erem Bilensoy

Beilstein J. Org. Chem. 2023, 19, 139–157, doi:10.3762/bjoc.19.14

Preparation of β-cyclodextrin/polysaccharide foams using saponin

• Max Petitjean and
• José Ramón Isasi

Beilstein J. Org. Chem. 2023, 19, 78–88, doi:10.3762/bjoc.19.7

• correlated to the foam stability. Morphology of the matrices studied by scanning electron microscopy (SEM) The different microstructures of the samples have been analysed for the three polysaccharide combinations. Those of β-cyclodextrin/LBG matrices will be shown here, since all the polysaccharides

• different times and the percent emergence of the liquid fraction was plotted vs time (see also Figure 1). Characterization of matrices: Scanning electron microscopy (SEM) of gold-sputter-coated samples was carried out using a Phenom Pro 739 microscope. Infrared analysis was carried out for the crushed

Inclusion complexes of the steroid hormones 17β-estradiol and progesterone with β- and γ-cyclodextrin hosts: syntheses, X-ray structures, thermal analyses and API solubility enhancements

• Alexios I. Vicatos,
• Zakiena Hoossen and
• Mino R. Caira

Beilstein J. Org. Chem. 2022, 18, 1749–1762, doi:10.3762/bjoc.18.184

• microscopy (HSM) analyses for all four complexes (Figures S9–S12 in Supporting Information File 1) and variable temperature powder X-ray diffraction (VTPXRD) analyses for β-CD·BES and β-CD·PRO (Figures S13 and S14 in Supporting Information File 1). The precise temperature onset values did not always

• performed on a Bruker Ultrashield 400 Plus Spectrometer (Billerica, Massachusetts, U.S.A.) and the program MestReNova was used to analyse the resulting data [48]. Thermal analysis Hot stage microscopy (HSM): The crystals were immersed in a small amount of silicone oil and heated at a constant rate of 10

• microscopy (HSM), variable temperature powder X-ray diffraction (VTPXRD) patterns, TGA, dTGA and DSC analytical data, details of electron counts derived from the Squeeze procedure, and geometrical parameters of the β-CD host molecules. Acknowledgements The authors acknowledge the University of Cape Town for

Formal total synthesis of macarpine via a Au(I)-catalyzed 6-endo-dig cycloisomerization strategy

• Jiayue Fu,
• Bingbing Li,
• Zefang Zhou,
• Maosheng Cheng,
• Lu Yang and
• Yongxiang Liu

Beilstein J. Org. Chem. 2022, 18, 1589–1595, doi:10.3762/bjoc.18.169

• -inflammatory [4][5][6][7][8], insecticidal, fungicidal, etc [9]. In addition to the above-mentioned activities, macarpine was also used as a DNA probe for flow cytometry and fluorescence microscopy due to its fluorescent properties [10]. Despite some research on the activities of macarpine had been performed

Mechanochemical bottom-up synthesis of phosphorus-linked, heptazine-based carbon nitrides using sodium phosphide

• Blaine G. Fiss,
• Georgia Douglas,
• Michael Ferguson,
• Jorge Becerra,
• Jesus Valdez,
• Trong-On Do,
• Tomislav Friščić and
• Audrey Moores

Beilstein J. Org. Chem. 2022, 18, 1203–1209, doi:10.3762/bjoc.18.125

• University, Québec City, Québec, Canada Facility for Electron Microscopy Research (FEMR), McGill University, Montréal, Québec, Canada Department of Materials Engineering, McGill University, 3610 University Street, Montréal, Québec, Canada 10.3762/bjoc.18.125 Abstract Herein, we present the bottom-up

• electron microscopy-electron energy loss spectroscopy (STEM-EELS). The STEM-EELS data for a g-h-PCN sample prior to annealing showed equal distribution of carbon and nitrogen with minimal phosphorus present, and particles roughly 400 nm in length (Supporting Information File 1, Figure S4a). Upon annealing

• Electron Microscopy Research (FEMR), the MC2 facility, McGill University Institute for Advanced Material (MIAM) for the use of their microscopy and spectroscopy equipment. Funding We are grateful for the support of the Natural Science and Engineering Research Council of Canada (NSERC) Discovery Grant and

Thermally activated delayed fluorescence (TADF) emitters: sensing and boosting spin-flipping by aggregation

• Ashish Kumar Mazumdar,
• Gyana Prakash Nanda,
• Nisha Yadav,
• Upasana Deori,
• Upasha Acharyya,
• Bahadur Sk and
• Pachaiyappan Rajamalli

Beilstein J. Org. Chem. 2022, 18, 1177–1187, doi:10.3762/bjoc.18.122

• % water/THF) of BPy-pTC were characterized using scanning electron microscopy (SEM). The SEM image showed the spherical nanoaggregates of BPy-pTC, with 95 nm diameter (Figure 3f). The BPy-p3C compound emitted in the green region at λem = 530 nm in THF, with a PLQY of 3.6% (Figure 3a). Similar to BPy-pTC

First series of N-alkylamino peptoid homooligomers: solution phase synthesis and conformational investigation

• Maxime Pypec,
• Laurent Jouffret,
• Claude Taillefumier and
• Olivier Roy

Beilstein J. Org. Chem. 2022, 18, 845–854, doi:10.3762/bjoc.18.85

• length, corresponding to the amide I C=O stretching of the N-(methylamino)amides functions. Preliminary transmission electron microscopy (TEM) analysis of dimer 2 seems to suggest ordered self-assembled multilayered structures (Figure S5 in Supporting Information File 1). This observation now needs to be

Tetraphenylethylene-embedded pillar[5]arene-based orthogonal self-assembly for efficient photocatalysis in water

• Zhihang Bai,
• Krishnasamy Velmurugan,
• Xueqi Tian,
• Minzan Zuo,
• Kaiya Wang and
• Xiao-Yu Hu

Beilstein J. Org. Chem. 2022, 18, 429–437, doi:10.3762/bjoc.18.45

• binding interaction between m-TPEWP5 and G is strong enough to form a stable complex in an aqueous solution. The morphology of the supramolecular m-TPEWP5G and m-TPEWP5G-EsY systems was monitored by using transmission electron microscopy (TEM). As shown in Figure 3, m-TPEWP5G self-assembled to form a worm

Recent developments and trends in the iron- and cobalt-catalyzed Sonogashira reactions

• Surendran Amrutha,
• Sankaran Radhika and
• Gopinathan Anilkumar

Beilstein J. Org. Chem. 2022, 18, 262–285, doi:10.3762/bjoc.18.31

• polymer) (Co@imine-POP) has been synthesized by immobilizing cobalt onto a nitrogen-rich porous organic polymer (Scheme 20) [35]. Using scanning electron microscopy, the surface morphology of the catalyst was evaluated. Nowadays, covalent organic frameworks (COF) were found to be a suitable support in

Synthesis and bioactivity of pyrrole-conjugated phosphopeptides

• Qiuxin Zhang,
• Weiyi Tan and
• Bing Xu

Beilstein J. Org. Chem. 2022, 18, 159–166, doi:10.3762/bjoc.18.17

• derivatives. Enzymatic conversion To further investigate the reason for the different activities in cell assays among the three compounds, 1, 4a and 6b, we employed transmission electron microscopy (TEM) to study the morphologies of the assemblies of these compounds before and after enzymatic

Green synthesis of C5–C6-unsubstituted 1,4-DHP scaffolds using an efficient Ni–chitosan nanocatalyst under ultrasonic conditions

• Soumyadip Basu,
• Sauvik Chatterjee,
• Suman Ray,
• Suvendu Maity,
• Prasanta Ghosh,
• Asim Bhaumik and
• Chhanda Mukhopadhyay

Beilstein J. Org. Chem. 2022, 18, 133–142, doi:10.3762/bjoc.18.14

• characterized by powder Fourier-transform infrared (FTIR) spectroscopy, X-ray diffraction (XRD) analysis, scanning electron microscopy (SEM), high-resolution transmission electron microscopy (HRTEM), energy-dispersive X-ray (EDX) spectroscopy, etc. It was effectively utilized in the eco-friendly synthesis of

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

• ][27][28]. Both methods are applied for fragmentation of initially µm-long SPBs based on BTU–PEO and BTP–PEO conjugates. The resulting nanofibers were characterized in detail by cryogenic transmission electron microscopy (cryoTEM), as well as by asymmetrical flow field-flow fractionation measurements

• ). cryoTEM investigations were performed at the electron microscopy facilities of the Jena Center for Soft Matter (JCSM), which were purchased with grants from the DFG and the European funds for Regional Development (EFRE). The funding of the collaborative research center PolyTarget, projects A05 and Z01