Synthesis of 1-indolyl-3,5,8-substituted γ-carbolines: one-pot solvent-free protocol and biological evaluation

• Premansh Dudhe,
• Mena Asha Krishnan,
• Kratika Yadav,
• Diptendu Roy,
• Krishnan Venkatasubbaiah,
• Biswarup Pathak and
• Venkatesh Chelvam

Beilstein J. Org. Chem. 2021, 17, 1453–1463, doi:10.3762/bjoc.17.101

• studies show that the γ-carbolines are highly toxic to cancer cells at micromolar concentrations similar to doxorubicin, whereas they are non-cytotoxic (Figure 6) to human macrophages or immune cells. At last, to evaluate cell uptake of the novel γ-carboline for fluorescence imaging, live-cell imaging

• Software, San Diego, CA). HeLa cell uptake study of γ-carboline 3ac A live-cell imaging experiment was performed with HeLa cells. The HeLa cells were placed in a 4-well confocal dish (cell count ≈ 100 cells per well) and incubated for 48 h at 37 °C under 5% CO2. After 3 h of incubation with carboline

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

• imbibing the water with high-speed that even imaging was not possible (see the video provided as Supporting Information File 2). It is known that the competition between the hydrophobic and hydrophilic character of hydrogels has a role in affecting water absorption and retention. In this regard

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

• used mass spectrometry profiling and imaging techniques with high spatial resolution and sensitivity to gain a new perspective on the mutualistic interactions between bacteria and macroalgae. Using atmospheric pressure scanning microprobe matrix-assisted laser desorption/ionisation high-resolution mass

• cLSM imaging analysis with a resolution to level of a single bacterial cell can be easily applied to other microbial consortia and their hosts. The novelty of this contribution is the use of an in situ setup designed to avoid all types of external contamination and interferences while resolving spatial

• distributions of metabolites and identifying specific symbiotic bacteria. Keywords: algae; AP-SMALDI; ectoine; holobiont; high-resolution mass spectrometry; mass spectrometry imaging; marine bacteria; Ulva; Introduction In intertidal zones with high temporal and spatial ecosystem variations, bacteria and

DNA with zwitterionic and negatively charged phosphate modifications: Formation of DNA triplexes, duplexes and cell uptake studies

• Yongdong Su,
• Maitsetseg Bayarjargal,
• Tracy K. Hale and
• Vyacheslav V. Filichev

Beilstein J. Org. Chem. 2021, 17, 749–761, doi:10.3762/bjoc.17.65

• Information Supporting Information File 62: Experimental part. Acknowledgements Manawatu Microscopy and Imaging Centre, NMR and mass spectrometry facilities at Massey University, and the assistance of Mr. Raoul Solomon, Dr. Patrick J. B. Edwards, and Mr. David Lun are gratefully acknowledged. We thank Dr

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

• Graduate School of Biomedical Sciences, Nagasaki University, 1-7-1 Sakamoto, Nagasaki 852-8501, Japan 10.3762/bjoc.17.45 Abstract Ligand-targeted microbubbles are focusing interest for molecular imaging and delivery of chemotherapeutics. Lipid–peptide conjugates (lipopeptides) that feature alternating

• . 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

• ; Introduction Various nano- and microsystems, including micelles, liposomes, and microbubbles, have been developed as imaging agents and to selectively deliver chemotherapeutics to tumor cells [1][2][3][4][5][6]. An increased specificity for tumor cells can be gained through ligand-mediated active targeting

¹⁹F NMR as a tool in chemical biology

• Diana Gimenez,
• Aoife Phelan,
• Cormac D. Murphy and
• Steven L. Cobb

Beilstein J. Org. Chem. 2021, 17, 293–318, doi:10.3762/bjoc.17.28

Supramolecular polymerization of sulfated dendritic peptide amphiphiles into multivalent L-selectin binders

• David Straßburger,
• Svenja Herziger,
• Katharina Huth,
• Moritz Urschbach,
• Rainer Haag and
• Pol Besenius

Beilstein J. Org. Chem. 2021, 17, 97–104, doi:10.3762/bjoc.17.10

• by the secondary structure formation (Figure 1). All samples for convential TEM imaging were prepared by placing 5 μL of the aqueous solution on a sample grid for 1 min, followed by the removal of the excess liquid using a filter paper and subsequent negative staining using a 2% uranyl acetate

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

• ]. These crystals found use in optoelectronic materials [14][15][16], as markers for imaging applications [12][13], and demonstrated anticancer properties [17]. However, control over the size and shape in such systems is challenging [8][9][10][11][12][13][14][15][16][17][18][19]. Surface chemistry

• performed cryo-TEM imaging of the early assembly stages. For the 5% THF assembly, monomolecular 1D stacks 1.5 ± 0.3 nm in width were observed after 1 min of aging (Figure 4A). The assembled material appeared as short fibers (10–80 nm length), some of which interact and align. For the 10% THF system

• were obtained. TEM TEM imaging was performed using a Tecnai T12 transmission electron microscope operated at 120 kV. Sample preparation: 8 µL of each sample was applied to a 400 mesh copper grid coated with carbon (on nitrocellulose support) and blotted 2 min later from the back side of the grid. Cryo

Molecular basis for protein–protein interactions

• Brandon Charles Seychell and
• Tobias Beck

Beilstein J. Org. Chem. 2021, 17, 1–10, doi:10.3762/bjoc.17.1

• Brandon Charles Seychell Tobias Beck Universität Hamburg, Department of Chemistry, Institute of Physical Chemistry, Grindelallee 117, 20146 Hamburg, Germany The Hamburg Centre for Ultrafast Imaging, Hamburg, Germany 10.3762/bjoc.17.1 Abstract This minireview provides an overview on the current

• by the Cluster of Excellence “CUI: Advanced Imaging of Matter“ of the Deutsche Forschungsgemeinschaft (DFG)–EXC 2056–project ID 390715994.

Metal-free nucleophilic trifluoromethylselenolation via an iodide-mediated umpolung reactivity of trifluoromethylselenotoluenesulfonate

• Kevin Grollier,
• Alexis Taponard,
• Arnaud De Zordo-Banliat,
• Emmanuel Magnier and
• Thierry Billard

Beilstein J. Org. Chem. 2020, 16, 3032–3037, doi:10.3762/bjoc.16.252

• , Institut Lavoisier de Versailles, 78035 Versailles Cedex, France CERMEP-In vivo imaging, Groupement Hospitalier Est, 59 Bd Pinel, 69677 Lyon, France 10.3762/bjoc.16.252 Abstract We report herein a practical method to generate CF3Se− (and RFSe−) anions from shelf-stable reagents under iodide activation

Selected peptide-based fluorescent probes for biological applications

• Debabrata Maity

Beilstein J. Org. Chem. 2020, 16, 2971–2982, doi:10.3762/bjoc.16.247

• , UMP, TBAP, MMP or other anions (SO42−, NO3−, HCO3−, CH3COO−) does not show any enhancement of fluorescence enabling the probe as selective for nucleoside triphosphates. The probe 1 is not toxic and has been demonstrated by fluorescence imaging of ATP in HeLa cells (Figure 2A, inset). Nucleic acid

• 4 binds with dsDNA in a combined intercalation and minor groove binding mode, whereas probe 5 binds with the outer surface of dsDNA. These two probes are low cytotoxic and probe 4 has been successfully used for imaging of nuclear DNA (Figure 5B, inset). Protein detection Specific peptides and

• lysosomal imaging (Figure 11) [64]. Peptide 14 contains two symmetric lysine-rich arms attached via their C-terminus to a central lysine spacer. Under high acidic conditions (pH > 2), the peptide 14 shows a sharp absorption band at 410 nm and relatively weak fluorescence at 623 nm, corresponding to the MCH

Naphthalonitriles featuring efficient emission in solution and in the solid state

• Sidharth Thulaseedharan Nair Sailaja,
• Iván Maisuls,
• Jutta Kösters,
• Alexander Hepp,
• Andreas Faust,
• Jens Voskuhl and
• Cristian A. Strassert

Beilstein J. Org. Chem. 2020, 16, 2960–2970, doi:10.3762/bjoc.16.246

• Wilhelms-Universität Münster, Heisenbergstraße 11, 48149 Münster, Germany European Institute for Molecular Imaging, Waldeyerstr.15, 48149 Münster, Germany Department of Nuclear Medicine, University Hospital Münster, Albert-Schweitzer-Campus 1, 48149 Münster, Germany Faculty of Chemistry (Organic Chemistry

• easy conversion into naphthalocyanines. Hence, peripherally substituted naphthalocyanines with push–pull character found widespread applications in non-lineal-optics (NLO) [36], photodynamic therapy [37] and photoacoustic imaging [38]. However, up to date, the literature reveals that there are no

• that H, Me, t-Bu, OMe, SMe and NMe2 represent excellent candidates as DSEgens. The combination of luminescence in both solutions and aggregated state enables future applications, such as data encryption, anti-counterfeiting [43] and non-invasive imaging for 3D tumor spheroids, considering that AIEgens

Encrypting messages with artificial bacterial receptors

• Pragati Kishore Prasad,
• Naama Lahav-Mankovski,
• Leila Motiei and
• David Margulies

Beilstein J. Org. Chem. 2020, 16, 2749–2756, doi:10.3762/bjoc.16.225

• (Figure 3). The first two receptors consist of DNA duplexes assembled from ODN-1 and FAM- or TAMRA-modified ODN-2 (FAM-ODN-2 or TAMRA-ODN-2), whereas the third receptor is a Cy5-modified ODN-1 (Cy5-ODN-1) [2]. Imaging the bacteria following washing, under the excitation and emission wavelengths of the

• grow in the same medium on a shaking incubator at 30 °C. Fluorescent imaging to study labeling during bacterial growth. The bacterial sample to be imaged was normalized to an OD600 = 0.3, suspended in 100 µL PBS, and placed on a glass-bottom dish (P35G-1.5-14-C; MatTek) precoated with poly-ʟ-lysine

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

• ][20][21][22][23][24][25][26], as mimicry of amyloids [27], in the context of intracellular phase transition [28], and in molecular imaging [29][30]. Most of these studies are centered on peptide amphiphiles or amphiphilic peptides that are linear in geometry. Nature, however, also produces and

Water-soluble host–guest complexes between fullerenes and a sugar-functionalized tribenzotriquinacene assembling to microspheres

• Si-Yuan Liu,
• Xin-Rui Wang,
• Man-Ping Li,
• Wen-Rong Xu and
• Dietmar Kuck

Beilstein J. Org. Chem. 2020, 16, 2551–2561, doi:10.3762/bjoc.16.207

• imaging. Freeze drying was conducted on a Scientz-18N freeze dryer (Scientz Biotech, Zhejiang, China). Synthesis of TBTQ-(OP)6. A mixture of TBTQ-(OH)6 (2.17 g, 5.56 mmol), potassium carbonate (9.23 g, 66.8 mmol), and propargyl bromide (5.40 g, 44.5 mmol, 98 wt %) in acetonitrile (100 mL) was stirred and

• , white: H for TBTQ-(OG)6; silver grey: C for C60). SEM images of (a) C60; (b) TBTQ-(OG)6; (c) and (d) TBTQ-(OG)6 C60 (C60: 1.4 mM; TBTQ-(OG)6: 1.4 mM in water, samples were freeze-dried and gold-sputtered before imaging). Synthetic route to TBTQ-(OG)6. Supporting Information Supporting Information File

Palladium nanoparticles supported on chitin-based nanomaterials as heterogeneous catalysts for the Heck coupling reaction

• Tony Jin,
• Malickah Hicks,
• Davis Kurdyla,
• Sabahudin Hrapovic,
• Edmond Lam and
• Audrey Moores

Beilstein J. Org. Chem. 2020, 16, 2477–2483, doi:10.3762/bjoc.16.201

• to the higher solubility of ChsNC. Both PdNP@ChNCs and PdNP@ChsNCs were imaged unstained to avoid any artefact in Pd imaging [19]. Dispersed “packets” of Pd NPs were observed for both samples, with far more packets observed for PdNP@ChNC (packet diameter of 42 ± 10 nm) samples compared to PdNP@ChsNC

Naphthalene diimide bis-guanidinio-carbonyl-pyrrole as a pH-switchable threading DNA intercalator

• Poulami Jana,
• Filip Šupljika,
• Carsten Schmuck and
• Ivo Piantanida

Beilstein J. Org. Chem. 2020, 16, 2201–2211, doi:10.3762/bjoc.16.185

• compound 4 to DNA. For each measurement, 10 μL of the mixed solution were deposited onto a freshly cleaned mica surface (Plano GmbH). The sample was dried by means of a spin-coater (1 min at 20 rps and 2 min at 100 rps). For the AFM imaging operating in the tapping mode (scan rate 5 μm s−1) with N-type

pH- and concentration-dependent supramolecular self-assembly of a naturally occurring octapeptide

• Goutam Ghosh and
• Gustavo Fernández

Beilstein J. Org. Chem. 2020, 16, 2017–2025, doi:10.3762/bjoc.16.168

• responsible for the lack of well-defined assemblies. This phenomenon is also supported by AFM imaging (Figure 3c and Figure 3d), where PEP-1 forms short fibrillar nanostructures with lengths of several hundred nanometers at pH 13.0. Interestingly, at a lower basic pH value, such as 10.3, PEP-1 formed an

Automated high-content imaging for cellular uptake, from the Schmuck cation to the latest cyclic oligochalcogenides

• Rémi Martinent,
• Javier López-Andarias,
• Dimitri Moreau,
• Yangyang Cheng,
• Naomi Sakai and
• Stefan Matile

Beilstein J. Org. Chem. 2020, 16, 2007–2016, doi:10.3762/bjoc.16.167

• high-content (HC) microscopy can satisfy this need. The automated imaging of thousands of cells per condition in multiwell plates allows us to obtain quantitative data on not only the fluorescence intensity but also on the localization in a very short time. Quantitative and statistically relevant

• results can be obtained from dose–response curves of the targeted delivery to selected cells and the cytotoxicity in the same experiment, even with poorly optimized cellular systems. Keywords: automation; cell-penetrating peptides; cellular uptake; cytosolic delivery; cytotoxicity; high-content imaging

• , using multiwell plates and registering data on the fluorescence intensity and fluorescence localization in thousands of cells per condition, at HT [56][57][58][59]. To properly assess its potential, automated HC imaging was optimized first. The fluorescence of the Hoechst dye and the GFP of the fusion

Clickable azide-functionalized bromoarylaldehydes – synthesis and photophysical characterization

• Dominik Göbel,
• Marius Friedrich,
• Enno Lork and
• Boris J. Nachtsheim

Beilstein J. Org. Chem. 2020, 16, 1683–1692, doi:10.3762/bjoc.16.139

• ][8], biological imaging [9][10][11][12] and chemical sensing [13][14][15]. Referring to the Jablonski diagram (see Scheme 1a) [16][17], upon excitation from the singlet ground state (S0) to higher singlet states (Sn), followed by internal conversion (IC), either non-radiative or radiative decay to S0

Pauson–Khand reaction of fluorinated compounds

• Jorge Escorihuela,
• Daniel M. Sedgwick,
• Alberto Llobat,
• Mercedes Medio-Simón,
• Pablo Barrio and
• Santos Fustero

Beilstein J. Org. Chem. 2020, 16, 1662–1682, doi:10.3762/bjoc.16.138

• use, fluorine-containing molecules have also found key applications in the field of medical diagnosis. Two of the most powerful imaging techniques used nowadays, positron-emission tomography (PET) and magnetic resonance imaging (MRI), are routinely carried out using fluorine-containing organic

Rearrangement of o-(pivaloylaminomethyl)benzaldehydes: an experimental and computational study

• Csilla Hargitai,
• Györgyi Koványi-Lax,
• Tamás Nagy,
• Péter Ábrányi-Balogh,
• András Dancsó,
• Gábor Tóth,
• Judit Halász,
• Angéla Pandur,
• Gyula Simig and
• Balázs Volk

Beilstein J. Org. Chem. 2020, 16, 1636–1648, doi:10.3762/bjoc.16.136

• Spider diffractometer (Tokyo, Japan) with imaging plate area detector using graphite monochromatic Cu Kα radiation. SC-XRD structures were deposited at the Cambridge Crystallographic Data Centre under the following numbers: CCDC 1953421 (3a), 1953424 (3b), 1953422 (8b), 1953423 (23a) and 1958809 (23b

Anthelmintic drug discovery: target identification, screening methods and the role of open science

• Frederick A. Partridge,
• Ruth Forman,
• Carole J. R. Bataille,
• Graham M. Wynne,
• Marina Nick,
• Angela J. Russell,
• Kathryn J. Else and
• David B. Sattelle

Beilstein J. Org. Chem. 2020, 16, 1203–1224, doi:10.3762/bjoc.16.105

• compound MMV665807 [125]. Wiggle Index, another ImageJ macro for difference thresholding and motility quantification has been extensively used for library-scale screening of exsheathed Haemonchus contortus L3s [127][128][129][130]. INVAPP Paragon, an imaging setup and MATLAB analysis script that again uses

• difference thresholding for motility quantification has been used for library screening with Trichuris muris and C. elegans [39][135][136]. CellProfiler is a major open source package for quantitatively measuring phenotypes from imaging data, particularly from high-throughput screens [139]. Some groups have

• CC BY 4.0 license [154]. Another 10-chamber worm isolation microfluidic device has been reported, originally for the imaging of worms to quantify the sleep behaviour during development, and the CAD file is made available in the supporting information [155]. The cost of the equipment is of course

Development of fluorinated benzils and bisbenzils as room-temperature phosphorescent molecules

• Shigeyuki Yamada,
• Takuya Higashida,
• Yizhou Wang,
• Masato Morita,
• Takuya Hosokai,
• Kaveendra Maduwantha,
• Kaveenga Rasika Koswattage and
• Tsutomu Konno

Beilstein J. Org. Chem. 2020, 16, 1154–1162, doi:10.3762/bjoc.16.102

• materials. Keywords: alkyne oxidation; benzils; bistolanes; fluorinated compounds; phosphorescence; Introduction The development of organic light-emitting molecules is recognized as one of the most important studies because of the broad application of these compounds as fluorescence probes, bio-imaging

The charge-assisted hydrogen-bonded organic framework (CAHOF) self-assembled from the conjugated acid of tetrakis(4-aminophenyl)methane and 2,6-naphthalenedisulfonate as a new class of recyclable Brønsted acid catalysts

• Svetlana A. Kuznetsova,
• Alexander S. Gak,
• Yulia V. Nelyubina,
• Vladimir A. Larionov,
• Han Li,
• Michael North,
• Vladimir P. Zhereb,
• Alexander F. Smol'yakov,
• Artem O. Dmitrienko,
• Michael G. Medvedev,
• Igor S. Gerasimov,
• Ashot S. Saghyan and
• Yuri N. Belokon

Beilstein J. Org. Chem. 2020, 16, 1124–1134, doi:10.3762/bjoc.16.99

• of 15–30 μm. SEM imaging of crystals of F-1 in the F-1a phase formed from a DMSO/water system indicated the existence of two types of crystals (Figure 4). Type 1 was a set of platelets with heights of 0.7–1 mm, grown from a common planar base with a diameter of 0.1–0.3 mm. In other words, the