Catalyzed and uncatalyzed procedures for the syntheses of isomeric covalent multi-indolyl hetero non-metallides: an account

• Ranadeep Talukdar

Beilstein J. Org. Chem. 2021, 17, 2102–2122, doi:10.3762/bjoc.17.137

• ]. Following the assumption (formation of triselenide 145) made by Wilshire [94] together with the detection of the oxidized products isatins in the reaction mixture, a disproportionation mechanism of SeO2 can be drawn giving bis(indol-3-yl)triselenide 145 and SeVI (Scheme 18e). The triselenide 145 converts

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

On the application of 3d metals for C–H activation toward bioactive compounds: The key step for the synthesis of silver bullets

• Renato L. Carvalho,
• Amanda S. de Miranda,
• Mateus P. Nunes,
• Roberto S. Gomes,
• Guilherme A. M. Jardim and
• Eufrânio N. da Silva Júnior

Beilstein J. Org. Chem. 2021, 17, 1849–1938, doi:10.3762/bjoc.17.126

Cerium-photocatalyzed aerobic oxidation of benzylic alcohols to aldehydes and ketones

• Girish Suresh Yedase,
• Sumit Kumar,
• Jessica Stahl,
• Burkhard König and
• Veera Reddy Yatham

Beilstein J. Org. Chem. 2021, 17, 1727–1732, doi:10.3762/bjoc.17.121

• transfer (LMCT) process, which reduces the CeIV species to CeIII, similarly as reported by Zuo and co-workers [57]. We chose (n-Bu4N)2CeIVCl6 as the CeIV source to ensure a sufficient solubility in organic solvents and to facilitate the detection of the species. The CeIV(OBn)Cln complex was prepared by

A systems-based framework to computationally describe putative transcription factors and signaling pathways regulating glycan biosynthesis

• Theodore Groth,
• Rudiyanto Gunawan and
• Sriram Neelamegham

Beilstein J. Org. Chem. 2021, 17, 1712–1724, doi:10.3762/bjoc.17.119

• , glycosaminoglycans, and glycolipids. Thus, multiple glycan changes may accompany oncological transformation. TF–glycogene communities in luminal and basal breast cancer Cytoscape plots were generated for luminal breast cancer (Figure 4a). Here, using the bipartite graph community detection methods [20], we

• (TFs and glycogenes), we treated TF–glycogene networks as bipartite and applied the corresponding procedure for community detection [20]. Firstly, the bipartite TF–glycogene graphs are projected into two different unipartite graphs, where TFs and glycogenes are placed into separate graphs. The edge

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

• underexplored technology [131]. Chemically reactive crosslinking PNA nucleobases: PNA has become a highly useful probe for detection of nucleic acids. Not surprisingly, chemists have developed reactive nucleobases for covalently crosslinking PNA and nucleic acid targets. 4-Amino-6-oxo-2-vinylpyrimidine (AOVP

• in cells and animal models Delivery and uptake of oligonucleotides to target tissues and cells is one of the greatest challenges for development of nucleic acid detection probes and therapeutics [14]. This problem is especially critical for in vivo applications of PNA because unmodified PNA, despite

Recent advances in the application of isoindigo derivatives in materials chemistry

• Andrei V. Bogdanov and
• Vladimir F. Mironov

Beilstein J. Org. Chem. 2021, 17, 1533–1564, doi:10.3762/bjoc.17.111

• = 0.07 cm2⋅V−1⋅s−1. Isoindigo-based sensor devices Isoindigo derivatives have begun to find an application in the design of sensor devices for the detection of simple and complex molecules in various aggregation states. Thus, it was shown that polymer structures based on isoindigo and thiophene 59a,b and

• towards n-butanol. The lower limit of detection was 100 ppm with a response time of less than 10 s. The ability of polymeric isoindigo derivatives to strongly bind to carbon nanotubes due to π-stacking was used to create sensors for the determination of NO2 in the gaseous state (see polymer 61) and

• glucose in solution (see polymer 62) [108][109]. The limit of sensitivity of the sensor for nitrogen dioxide was 60 ppm and for glucose 0.026 mM. For the example of the fairly simple arylamine series 63, the possibility of using isoindigo polymer for the detection of explosives (trinitrophenol and

Substituted nitrogen-bridged diazocines

• Pascal Lentes,
• Jeremy Rudtke,
• Thomas Griebenow and
• Rainer Herges

Beilstein J. Org. Chem. 2021, 17, 1503–1508, doi:10.3762/bjoc.17.107

• . Moreover, the photoconversion yield for the E→Z isomerization is quantitative (within the detection limit of UV and NMR spectroscopy). A high efficiency in switching the biological activity off is important to avoid side effects of residual concentrations of the active form [13]. Water solubility and high

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

• was hybridized with a DNA target. The double-headed nucleoside 41 has potential in DNA invader probes as well as in RNA targeting and detection [23]. 1,3-Furanosyl double-headed nucleosides In this section, all double-headed nucleosides with furanosyl ring structures are collected. The first

Analogs of the carotane antibiotic fulvoferruginin from submerged cultures of a Thai Marasmius sp.

• Birthe Sandargo,
• Leon Kaysan,
• Rémy B. Teponno,
• Christian Richter,
• Benjarong Thongbai,
• Frank Surup and
• Marc Stadler

Beilstein J. Org. Chem. 2021, 17, 1385–1391, doi:10.3762/bjoc.17.97

• min, flow rate: 0.6 mL/min, UV detection 200–600 nm, was used to obtain the HRESIMS data. NMR spectra were acquired on a Bruker Avance III 700 MHz spectrometer (Bremen, Germany) equipped with a 5 mm TCI cryoprobe (1H NMR (700 MHz), 13C NMR (175 MHz)). Optical rotations of the metabolites were measured

• % FA served as mobile phase, running a gradient of 10 min at 5% acetonitrile + 0.1% FA, then increasing to 100% within 70 min, flow rate: 40 mL/min, UV detection at 200–600 nm. Pre-fractions were further separated using a Luna C18(2) 250 × 21 mm, 7 μm column (Phenomenex, Aschaffenburg, Germany) and

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

• ). Pellets with VLP-dsRNAvp28 prepared with commercial binders (Dry Oil® and NutriKelp®) are described in Supporting Information File 1. Detection of WSSV by real-time quantitative PCR. The real-time PCR (qPCR) for quantitation of WSSV was performed using DNA isolated from shrimp muscle tissue and TaqMan

• concentration range of the standard curve was 3.9 × 109 to 3.9 × 104 copies/ng. The ABI StepOnePlus v2.0 sequence detection system software (Applied Biosystems, USA) was used. Amplification reactions included all shrimp were analyzed (alive, dying and dead) from each experimental group. The viral load of WSSV

• considered significant. For the WSSV detection, an analysis of variance (ANOVA) was used to compare the average number of copies of WSSV and the average number of copies between treatments was analyzed with the Tukey’s test (a = 0.05). The Student's t-test was used to obtain significant differences (t – 95

Icilio Guareschi and his amazing “1897 reaction”

• Gian Cesare Tron,
• Alberto Minassi,
• Giovanni Sorba,
• Mara Fausone and
• Giovanni Appendino

Beilstein J. Org. Chem. 2021, 17, 1335–1351, doi:10.3762/bjoc.17.93

• involvement of Guareschi in the first edition of the Italian Pharmacopoeia was accompanied by the production of an extensive commentary to be used by both pharmacists and industrialists. In connection with his interest in chemistry and art, Guareschi described a color reaction for the selective detection of

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

• (1024 × 1024) were acquired using a Zeiss cLSM 880 (Carl Zeiss AG, Oberkochen, Germany) with a Plan-Apochromat 20 × 0.8 and 488 nm Argon-laser excitation (5% transmission). Emission wavelengths for SYBR Gold (490–650 nm) and chlorophyll A (653–735 nm) were separated via the spectral detection unit

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

• bisporophyrin via reaction of the starting material with PhLi followed by in situ oxidation to a radical anion and dimerization [55]. While formation of 5,10,15-trisubstituted porphyrins and 5,10,15,20-tetrasubstituted porphyrins was anticipated as side products, the detection of the title compound 4 was

Metal-free glycosylation with glycosyl fluorides in liquid SO₂

• Krista Gulbe,
• Jevgeņija Lugiņina,
• Edijs Jansons,
• Artis Kinens and
• Māris Turks

Beilstein J. Org. Chem. 2021, 17, 964–976, doi:10.3762/bjoc.17.78

• can be performed in widely available glass pressure tubes. Detection of the FSO2− species by 19F NMR (471 MHz, D2O). Computational study of reaction mechanism α-11 + MeOH → α-13c in the presence of and in absence of SO2 (Gaussian 09, Revision D.01; Gaussian, Inc.; m052x method and the 6-31+g(d) basis

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

• percentage of Cy5-positive cell detection and a higher MFI compared to the hCMEC/D3 barrier (Figure 2D and Supporting Information File 1, Figure S4). Collectively, these data suggest that the candidate LNPs, particularly LNP B9 G-3 T7, may increase uptake through tight junctions and prove useful in

• Nano ZS (Malvern Instruments, UK), having He–Ne 633 nm laser at an angle of detection of 90°, with an incubation time of 60 s. Samples were diluted 50-fold in Milli-Q water and placed into the disposable plastic cuvettes for measurement performed in triplicates (n ≥ 3) to obtain a mean value. NTA

• h later, the apical layer was removed, and the basolateral cells were washed, trypsinized, and resuspended in 1× PBS. Detection of Cy5 was measured by flow cytometry on a BD Accuri™ C6 device (Becton, Dickinson and Company, NJ), and the data was analyzed using FlowJo™ Version 10.7.1 (Becton

Microwave-assisted multicomponent reactions in heterocyclic chemistry and mechanistic aspects

• Shivani Gulati,
• Stephy Elza John and
• Nagula Shankaraiah

Beilstein J. Org. Chem. 2021, 17, 819–865, doi:10.3762/bjoc.17.71

• organic synthesis (2000–10), witnessed microwaves with optic fibre or IR pyrometers for temperature detection along with specific glass reaction vessels that can withstand pressure and temperature in the reaction generated especially by low boiling solvents. Microwave-assisted heating reduces reaction

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

• blood circulation times by allowing them to evade immune detection. PEGs often play a key role in the design of the ligands as a spacer between the nanocarrier surface and the lipid. PEGs have, however, some shortcomings, such as a broad molecular weight distribution, large steric hindrance, and the

Identification of volatiles from six marine Celeribacter strains

• Anuj Kumar Chhalodia,
• Jan Rinkel,
• Dorota Konvalinkova,
• Jörn Petersen and
• Jeroen S. Dickschat

Beilstein J. Org. Chem. 2021, 17, 420–430, doi:10.3762/bjoc.17.38

• (indole-2H5)tryptophan were performed, but none of these experiments resulted in a detectable incorporation of labeling. Conclusively, a non-biological origin of this part of the molecule seems likely, which may also explain why the detection of 41 in Celeribacter was not always reproducible. Notably, 2

1,2,3-Triazoles as leaving groups: S_NAr reactions of 2,6-bistriazolylpurines with O- and C-nucleophiles

• Dace Cīrule,
• Irina Novosjolova,
• Ērika Bizdēna and
• Māris Turks

Beilstein J. Org. Chem. 2021, 17, 410–419, doi:10.3762/bjoc.17.37

• Agilent Technologies 1200 Series chromatograph equipped with an Agilent XDB-C18 (4.6 × 50 mm, 1.8 µm) column was used. Eluent A: 0.1% TFA solution with 5% v/v MeCN added; eluent B – MeCN. Gradient: 10–95% B 5 min, 95% B 5 min, 95–10% B 2 min. Flow: 1 mL/min. Wavelength of detection was 260 nm. LC–MS was

Regioselective chemoenzymatic syntheses of ferulate conjugates as chromogenic substrates for feruloyl esterases

• Olga Gherbovet,
• Fernando Ferreira,
• Apolline Clément,
• Mélanie Ragon,
• Julien Durand,
• Sophie Bozonnet,
• Michael J. O'Donohue and
• Régis Fauré

Beilstein J. Org. Chem. 2021, 17, 325–333, doi:10.3762/bjoc.17.30

• , France 10.3762/bjoc.17.30 Abstract Generally, carbohydrate-active enzymes are studied using chromogenic substrates that provide quick and easy color-based detection of enzyme-mediated hydrolysis. For feruloyl esterases, commercially available chromogenic ferulate derivatives are both costly and limited

• lignocellulosic matrix. Moreover, Faes are useful tools to obtain commercially relevant ferulic acid, which represents up to 3 wt % of plant the cell wall dry weight [8]. So far, the detection and characterization of Faes has mainly relied on either the use of HPLC or on UV–visible spectrophotometry, using

• ] and (ii) spontaneous oxidation and subsequent dimerization forming the insoluble blue 5-bromo-4-chloro-substituted indigo dye [15]. In an alternative demonstration, 1a was also used for colony level detection of FAE using yeast cells (Yarrowia lipolytica [30]) that actually coexpressed AnFaeA and

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

• estrogen receptor (ER) co-activator peptides and enabled the sensitive detection of their protein–peptide interaction inhibition by the ER antagonist tamoxifen [20]. Significantly, different secondary structure conformational preferences were also found among the diastereomers of perfluoro-tert

• the aforementioned issues, Virta and co-workers have explored the application of trifluoromethyl analogues of guanosine, cytidine and uridine based in 2’-O-[(4-trifluoromethyltriazol-1-yl)methyl] reporter groups as 19F NMR probes for the detection of RNA secondary structures (Figure 14). As shown by

• , but only one could be detected (SF5-catechol) despite the 19F NMR analysis showing the presence of multiple fluorometabolites. Detection and biosynthesis of natural organofluorine compounds As naturally-occurring organofluorine compounds are so rare, it is possible to easily detect them in a crude

1,2,3-Triazoles as leaving groups in S_NAr–Arbuzov reactions: synthesis of C6-phosphonated purine derivatives

• Kārlis-Ēriks Kriķis,
• Irina Novosjolova,
• Anatoly Mishnev and
• Māris Turks

Beilstein J. Org. Chem. 2021, 17, 193–202, doi:10.3762/bjoc.17.19

• an Agilent Technologies 1200 Series system equipped with an XBridge C18 column, 4.6 × 150 mm, particle size 3.5 μm, with a flow rate of 1 mL/min, using eluent A–0.1% TFA/H2O with 5 vol % MeCN and eluent B–MeCN as the mobile phase. The wavelength of detection was 260 nm. Gradient: 30–95% B 5 min, 95

The fluorescence of a mercury probe based on osthol

• Guangyan Luo,
• Zhishu Zeng,
• Lin Zhang,
• Zhu Tao and
• Qianjun Zhang

Beilstein J. Org. Chem. 2021, 17, 22–27, doi:10.3762/bjoc.17.3

• selectivity for Hg2+. The fluorescence intensity of OST showed a good linear correlation with the Hg2+ concentration (6.0 × 10−5 to 24.0 × 10−5 mol∙L−1, R2 = 0.9954), and the detection limit of the probe was 5.04 × 10−8 mol∙L−1, which can be used for the determination of Hg2+ traces. Keywords: fluorescence

• irreversible nerve damage. Therefore, it is very important to develop a highly sensitive and selective method for mercury detection. At present, the detection of mercury mainly includes atomic absorption and atomic emission spectrometry [4], inductively coupled plasma mass spectrometry [5][6], and capillary

• electrophoresis [7]. However, the application of these analytical methods in mercury detection is limited due to the complex sample pretreatment procedures, expensive instruments, and other factors [8][9]. Fluorescent-probe instruments have been widely used due to the advantages of the simple operation, low cost

Synthesis, crystal structures and properties of carbazole-based [6]helicenes fused with an azine ring

• Daria I. Tonkoglazova,
• Anna V. Gulevskaya,
• Konstantin A. Chistyakov and
• Olga I. Askalepova

Beilstein J. Org. Chem. 2021, 17, 11–21, doi:10.3762/bjoc.17.2

• -detection (see Supporting Information File 1, Figures S38–S40). X-ray molecular structures The structures of the title compounds 10a–c were further explored by a single-crystal X-ray diffraction analysis (Figure 1, see also Supporting Information File 1, Figures S35–S37 and Table S1) and compared with that