Menadione: a platform and a target to valuable compounds synthesis

• Acácio S. de Souza,
• Ruan Carlos B. Ribeiro,
• Dora C. S. Costa,
• Fernanda P. Pauli,
• David R. Pinho,
• Matheus G. de Moraes,
• Fernando de C. da Silva,
• Luana da S. M. Forezi and
• Vitor F. Ferreira

Beilstein J. Org. Chem. 2022, 18, 381–419, doi:10.3762/bjoc.18.43

• (DNA and RNA), enzymes, structural proteins, and cell membrane lipids. These effects can lead to dysfunctions that activate the apoptosis process resulting in cell death [42][43][44][45][46]. In addition to participating in redox cycles as biomolecules in various biochemical processes, the 1,4

Flow synthesis of oxadiazoles coupled with sequential in-line extraction and chromatography

• Kian Donnelly and
• Marcus Baumann

Beilstein J. Org. Chem. 2022, 18, 232–239, doi:10.3762/bjoc.18.27

• ], however, many of them involve the use of expensive and complex membrane filters. To reduce cost and increase simplicity we opted to use a ‘home-made’ setup to achieve continuous separation which consisted of a laboratory separating funnel, into which we collect the biphasic reaction output following

1,2-Naphthoquinone-4-sulfonic acid salts in organic synthesis

• Ruan Carlos B. Ribeiro,
• Patricia G. Ferreira,
• Amanda de A. Borges,
• Luana da S. M. Forezi,
• Fernando de Carvalho da Silva and
• Vitor F. Ferreira

Beilstein J. Org. Chem. 2022, 18, 53–69, doi:10.3762/bjoc.18.5

• cause several damages to its components, such as carbohydrates, lipids, membrane components, and enzymes that are critical for DNA replication [9][10][11][12]. Most synthetic strategies toward naphthoquinones with potential biological activity start from natural and synthetic naphthoquinones, inserting

Peptide stapling by late-stage Suzuki–Miyaura cross-coupling

• Hendrik Gruß,
• Rebecca C. Feiner,
• Ridhiwan Mseya,
• David C. Schröder,
• Michał Jewgiński,
• Kristian M. Müller,
• Rafał Latajka,
• Antoine Marion and
• Norbert Sewald

Beilstein J. Org. Chem. 2022, 18, 1–12, doi:10.3762/bjoc.18.1

• –Miyaura cross-coupling; Introduction Peptide cyclisation emerged as a popular approach to limit conformational mobility in order to enhance the binding affinity towards a biological target. Moreover, cyclic peptides are more stable against proteolytic digestion and can provide an improved membrane

Biological properties and conformational studies of amphiphilic Pd(II) and Ni(II) complexes bearing functionalized aroylaminocarbo-N-thioylpyrrolinate units

• Samet Poyraz,
• Samet Belveren,
• Sabriye Aydınoğlu,
• Mahmut Ulger,
• Abel de Cózar,
• Maria de Gracia Retamosa,
• Jose M. Sansano and
• H. Ali Döndaş

Beilstein J. Org. Chem. 2021, 17, 2812–2821, doi:10.3762/bjoc.17.192

• cellular targets known for antituberculosis drugs and all the different chemical structures (inhibition of cell wall synthesis, disruption of the plasma membrane, DNA-gyrase, etc.) the next work focused on determining the exact biological mechanism and docking studies could not be executed. Conclusion The

• ). To obtain an initial concentration of 1000 μg/mL, the novel synthesized compounds were dissolved in DMSO to prepare stock solutions and then, 0.22 μm membrane filters were used to sterilization of the compounds. Serial two-fold dilutions of the compounds and ampicillin (standard reference drug) were

Highly stereocontrolled total synthesis of racemic codonopsinol B through isoxazolidine-4,5-diol vinylation

• Lukáš Ďurina,
• Anna Ďurinová,
• František Trejtnar,
• Ľuboš Janotka,
• Lucia Messingerová,
• Jana Doháňošová,
• Ján Moncol and
• Róbert Fischer

Beilstein J. Org. Chem. 2021, 17, 2781–2786, doi:10.3762/bjoc.17.188

• core. It is proven that the presence of lipophilic groups in the structure of such compounds improves their penetration trough the cell membrane, and thereby increases their antitumor effectiveness [40]. Conclusion In summary, we have developed an efficient highly diastereoselective synthesis of

The ethoxycarbonyl group as both activating and protective group in N-acyl-Pictet–Spengler reactions using methoxystyrenes. A short approach to racemic 1-benzyltetrahydroisoquinoline alkaloids

• Marco Keller,
• Karl Sauvageot-Witzku,
• Franz Geisslinger,
• Nicole Urban,
• Michael Schaefer,
• Karin Bartel and
• Franz Bracher

Beilstein J. Org. Chem. 2021, 17, 2716–2725, doi:10.3762/bjoc.17.183

• plate reader (FLIPR) built into a robotic liquid handling station (Fluent, Tecan, Switzerland) and a HEK293 cell line stably expressing the human TPC2 (C-terminally RFP-tagged) rerouted to the plasma membrane as previously described [57]. Trypsinized HEK293 cells (stably expressing hTPC2L11A/L12A

Synthetic strategies toward 1,3-oxathiolane nucleoside analogues

• Umesh P. Aher,
• Dhananjai Srivastava,
• Girij P. Singh and
• Jayashree B. S

Beilstein J. Org. Chem. 2021, 17, 2680–2715, doi:10.3762/bjoc.17.182

• was devised for targeting specific receptors on the leukocytes membrane. The crucial N-glycosylation reaction between 1,3-oxathiolane precursor 45 and silylated cytosine was carried out using TiCl4 as a catalyst. The N-acylation of compound 92a was performed for flash chromatography, and further

Synthesis of new bile acid-fused tetrazoles using the Schmidt reaction

• Dušan Đ. Škorić,
• Olivera R. Klisurić,
• Dimitar S. Jakimov,
• Marija N. Sakač and
• János J. Csanádi

Beilstein J. Org. Chem. 2021, 17, 2611–2620, doi:10.3762/bjoc.17.174

• material [4][5][6][7]. Aggregation and interactions with the cell membrane of bile acid molecules can alter drug action [8][9]. Our previous work showed that bile acids could interact with certain drug molecules and improve their biological activity [10][11]. To evade the membranolytic action of natural

Strategies for the synthesis of brevipolides

• Yudhi D. Kurniawan and
• A'liyatur Rosyidah

Beilstein J. Org. Chem. 2021, 17, 2399–2416, doi:10.3762/bjoc.17.157

• , entries 1–7). A very low ED50 value of 8.5 nM was obtained for brevipolide C (3) (Table 2, entry 3) [4], making it a very potent lead compound for anticancer candidates related to mitochondrial dysfunction effect. A reduction in the mitochondrial membrane potential (MMP) could also indicate apoptosis [20

Isolation and characterization of new phenolic siderophores with antimicrobial properties from Pseudomonas sp. UIAU-6B

• Emmanuel T. Oluwabusola,
• Olusoji O. Adebisi,
• Fernando Reyes,
• Kojo S. Acquah,
• Mercedes De La Cruz,
• Larry L. Mweetwa,
• Joy E. Rajakulendran,
• Digby F. Warner,
• Deng Hai,
• Rainer Ebel and
• Marcel Jaspars

Beilstein J. Org. Chem. 2021, 17, 2390–2398, doi:10.3762/bjoc.17.156

• addition of 1 M HCl (20 µL), diluted with acetonitrile (100 µL), and filtered through a PTFE membrane filter (0.45 µm). The standard amino acids (ᴅ-Thr, ʟ-Thr, and ʟ-allo-Thr) were subjected to derivatization with ʟ-FDAA by using the same method previously described. For the HPLC analysis, mixtures of the

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

• peptides and proteins have been linked to nanotechnology. DQA and TPP are both cationic and lipophilic molecules and therefore able to easily pass the mitochondrial membrane [15][16][17][18][19]. TPP is the most-studied mitochondrial targeting agent and has shown to accumulate 1000 times more in the

Halides as versatile anions in asymmetric anion-binding organocatalysis

• Lukas Schifferer,
• Martin Stinglhamer,
• Kirandeep Kaur and
• Olga García Macheño

Beilstein J. Org. Chem. 2021, 17, 2270–2286, doi:10.3762/bjoc.17.145

• , the regulation of membrane potentials is one of such applications, in which the transport of chloride anions is facilitated by noncovalent hydrogen bonding interactions (Figure 1a) [6]. Noncovalent interactions are in fact one of the essential factors for the molecular recognition in enzymatic

(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

• the antibiotic gentamicin, and all cell lines were grown in a cell culture bottle, which had a 0.22 µm pore membrane filter on the lid, allowing the circulation of CO2. WSS-1 cells grew adherently, while cells of the K562 strain grew in suspension. All strains were maintained at 35 °C, at 5% CO2. Cell

Chemical syntheses and salient features of azulene-containing homo- and copolymers

• Vijayendra S. Shetti

Beilstein J. Org. Chem. 2021, 17, 2164–2185, doi:10.3762/bjoc.17.139

• case of protonated emeraldine. The Nafion membrane doped with protonated polyaminoazulene 31 displayed good proton conductivity and reduced methanol permeability, making it suitable for methanol fuel cell applications. Azulene-containing copolymers Azulene-thiophene/bithiophene copolymers Lai and co

• polyanilines and can be a useful proton-conducting membrane material in methanol fuel cells. Also, as azulenes are known to contravene Kasha’s rule, it is intriguing to explore, how their presence in the polymers can favor the energy utilization from higher excited states. This may lead to a new dimension in

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

Cationic oligonucleotide derivatives and conjugates: A favorable approach for enhanced DNA and RNA targeting oligonucleotides

• Mathias B. Danielsen and
• Jesper Wengel

Beilstein J. Org. Chem. 2021, 17, 1828–1848, doi:10.3762/bjoc.17.125

• membrane permeability of ASOs. A reduction in the net negative charge may have beneficial delivery-related effects in addition to other possible effects such as improved resistance towards nuclease degradation or increased binding to the negatively charged RNA complements, the latter as a result of reduced

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

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

• entry, binding and assembly of the virion. Previous studies have shown that silencing these structural proteins in WSSV challenge assays, increases shrimp survival [10][11][17][18][19][20][21]. The VP28 glycoprotein plays an important role in systemic infection by interacting with cell membrane proteins

• mg each) were homogenized in 900 µL (1:10 ratio; mg/µL) of TN buffer (20 mM Tris-HCl, 400 mM NaCl, pH 7.4). The homogenized solution was centrifuged in two steps at 1800 and 3000g for 20 min, respectively, at 4 °C. The supernatant was recovered and filtered through a membrane filter (0.45 µm VWR

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

• polar metabolite was linked to the metabolic homeostasis of Ulva lactuca during tidal cycles [30]. Choline is the precursor of the membrane constituent phosphatidylcholine [31]. We inferred that the accumulation of choline in axenic U. mutabilis germlings might correlate with the absence of the key

• bacterial morphogen thallusin, which induces cell wall and rhizoid formation. The accompanying formation of cell wall protrusions might disrupt the cell membrane arrangement indicated by choline accumulation. Screening the tripartite community Ulva–Roseovarius–Maribacter identified ectoine as a metabolic

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

• such as membrane-based continuous separators [52][53][54][55] has come a long way in aiding with in-line purification and work-up issues. Table 4 provides a general summary list of advantages and disadvantages of a flow approach. There are multiple possible configuration and module combinations of

• coated multichannel microreactor with an integrated zeolite ZSM-5 membrane (Scheme 28) [156][157]. The heterogeneous catalyst used was a Cs-exchanged faujasite NaX. The membrane maximised the outcomes in comparison to tested fixed-bed and microreactors. The ZSM-5 membrane allowed fast water exclusion

• faujasite NaX was reported [158], along with a ZIF-8/NaA composite membrane microreactor [159]. These systems embodied more active and stable catalysts which were able to consequently operate for over 50 hours with delivery of excellent product yields (>95%). Also these systems, instead of using membranes

Synthesis of 10-O-aryl-substituted berberine derivatives by Chan–Evans–Lam coupling and investigation of their DNA-binding properties

• Peter Jonas Wickhorst,
• Mathilda Blachnik,
• Denisa Lagumdzija and
• Heiko Ihmels

Beilstein J. Org. Chem. 2021, 17, 991–1000, doi:10.3762/bjoc.17.81

• : 6.0 mM Na2HPO4, 2.0 mM NaH2PO4, 1.0 mM Na2EDTA; pH 7.0. All buffer solutions were prepared from purified water (resistivity 18 MΩ cm) and biochemistry-grade chemicals. The buffer solutions were filtered through a PVDF membrane filter (pore size 0.45 μm) prior to use. Structures and numbering of

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

• dipalmitoyl-Dap-T7 and dipalmitoyl-Dap-Tat (Figure 1A). Double lipidation ensures a more stable lipid-membrane-anchoring compared to a single fatty acid chain or cholesteryl variant [27][28][29]. The careful choice of Dap and palmitic acid allows for the entire synthesis to be performed on solid support with

• allowed to slowly reach rt, transferred to a 1 mL Hamilton syringe, and extruded 10 times at rt through two 100 nm Nucleopore membrane filters (Whatman) using Avanti Mini Extruder (Avanti Polar Lipids, Inc., USA). Complementary oligonucleotides GP160:A-1 (1.4 nmol, 30 μL 1× PBS pH 7.4) and CCR5:G-3 (1.4

• subsequently incubated overnight at 4 °C with Claudin 5–Alexa Fluor 488 (catalog number 35-258-8, Thermo Fisher Scientific, MA) at 5 µg/mL in 1% BSA–PBS. Thereafter, cells were washed three times with ice-cold PBS. The membrane was subsequently cut out of the insert with a scalpel blade and, using tweezers

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

• ) and for the N+-modified oligos (Figure 3B, H, and K, respectively). Confocal microscope sections that dissect the nucleus were collected showing that the FAM-ON imaged were in the cytoplasm when localised adjacent to the nucleus and not on the cell surface. Staining of the cell membrane, along with

• -ON for 12 hours, then stained with CellBrite Fix 640 (Biotium) to identify the cell membrane before fixation with 4% paraformaldehyde. Nuclear DNA was then stained with Hoechst 3342 and images collected with a Leica SP5 DM6000B scanning confocal microscope. Overlaid pseudo-coloured panels of a

• section are shown: nuclear DNA (blue), 4Ts-FAM/ON (magenta), cell membrane (yellow). Scale bar: 20 μm. The synthesis of ONs with Ts and N+ modification using the Staudinger reaction during the solid-phase DNA synthesis. Conditions: (i) 0.5 M TsN3, MeCN, 37 °C, 30 min for Ts modification; 0.7 M 4

Simulating the enzymes of ganglioside biosynthesis with Glycologue

• Andrew G. McDonald and
• Gavin P. Davey

Beilstein J. Org. Chem. 2021, 17, 739–748, doi:10.3762/bjoc.17.64

• then to subsequent ceramide-linked glycoconjugate acceptors, before transport and eventual incorporation into the plasma membrane via vesicular fusion. Gangliosides, which function as antigenic determinants [4], may play a role in membrane organization [5], cell signaling [6], apoptosis [7], and in

• memory formation through neuromodulation of synaptic transmission [8]. Gangliosides are recycled in the lysosome through the action of glycohydrolases. The inhibition of membrane recycling has been shown to lead to an accumulation of lysosomal gangliosides resulting in neuronal death [9]. Congenital