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Search for "enrichment" in Full Text gives 74 result(s) in Beilstein Journal of Organic Chemistry.
C–C Coupling in sterically demanding porphyrin environments
Beilstein J. Org. Chem. 2024, 20, 2784–2798, doi:10.3762/bjoc.20.234
- explored, or further changes in the pH of the solution. Enrichment to the αβαβ-atropisomer may also be favorable [50], as to alleviate the steric hindrance caused by the short distances (4.3–4.4 Å) between bromines in the α2β2-atropisomers (cf., Figure 5). Borylation and further coupling of
- previously, enrichment to the αβαβ, isomer may be necessary to remove the impact of opposing bromine atoms on the coupling reaction. Separation of the four individual atropisomers (αβαβ, α2β2, α3β, α4) has been accomplished before in dodecasubstituted porphyrins through Ni(II) metalation [15]. The core
- , even with Ni(II) metalation. There are many other methods available to achieve different desired atropisomeric ratios. These include thermal enrichment [67][68], photoracemization [69][70], axial-ligand coordination [71], precise separation techniques [50] or a combination of the procedures mentioned
Improved deconvolution of natural products’ protein targets using diagnostic ions from chemical proteomics linkers
Beilstein J. Org. Chem. 2024, 20, 2323–2341, doi:10.3762/bjoc.20.199
- ][36][37]. A covalent bond between a probe and a protein is needed because of denaturing conditions used during the analysis. In contrast, relying on a noncovalent interaction would result in loss of the probe–protein interaction. The bioorthogonal handle is therefore essential for an enrichment or
- speed of acquisition of mass spectra leads to ever better coverage of proteomes submitted for analysis, the throughput has not yet reached the point in which all peptides and their modified forms can be identified and characterized in a single experiment. Therefore, an enrichment of the probe-modified
- pipelines enable to obtain more information from already established workflows, because they are becoming practically feasible only now. These will be discussed further in this review. We primarily focus on the linkers utilized for enrichment and identification of the probe–protein conjugates resembling
Polymer degrading marine Microbulbifer bacteria: an un(der)utilized source of chemical and biocatalytic novelty
Beilstein J. Org. Chem. 2024, 20, 1635–1651, doi:10.3762/bjoc.20.146
- Microbulbifer strains may require repeated rounds of serial enrichment. This genus was first described by Gonzales et al. in 1997 [5]. More than 130 strains have been reported from regions of wide geographical dispersion (Table 1, Figure 1). Microbulbifer bacteria are well known for their capacity to degrade
- group in 25 is rare. Feeding [1-13C]acetate to the culture resulted the enrichment of C1, C3, C5, C7, and C9 carbons, which verified the origin of the carbon skeleton as being fatty acid-derived. Feeding experiments with ʟ-[methyl-13C]methionine yielded only enrichment of C11 methyl, indicating that
Diameter-selective extraction of single-walled carbon nanotubes by interlocking with Cu-tethered square nanobrackets
Beilstein J. Org. Chem. 2024, 20, 1298–1307, doi:10.3762/bjoc.20.113
- recovered through demetalation of the interlocked ones along with the nanobracket. Raman and absorption spectroscopies of the extracted SWNTs reveals the diameter enrichment of only several kinds of SWNTs in the diameter range from 0.94 to 1.10 nm among ≈20 kinds of SWNTs from 0.76 to 1.20 nm in their
- . Characterization of the extracted SWNTs To evaluate the diameter enrichment of the extracted SWNTs, Raman spectra are measured at 488, 633 and 785 nm excitation wavelengths for the p-SWNTs. In the RBM region, the Raman shift of the signal is known to be inversely proportional to the diameter of SWNTs. Even though
- 136000g. The absorption spectrum of the supernatant was measured to evaluate the diameter enrichment. As shown in Figure 5b, (8,6)-, (12,1)-, (11,3)-, (10,3)-, and (9,5)-SWNTs in the semiconducting region (ES11) and (8,5)-, (7,7)-, (13,1)-, (12,3)-SWNTs in the metallic region (EM11) are enriched as
Switchable molecular tweezers: design and applications
Beilstein J. Org. Chem. 2024, 20, 504–539, doi:10.3762/bjoc.20.45
- achieved by chemical (hydroxide/proton) or electrochemical (reduction/oxidation) stimuli allowing the enrichment of perylene from a mixture of polycyclic aromatic hydrocarbons (PAHs) in phase-transfer experiments into a perfluorocarbon phase. Metal cation responsive tweezers In the early 2000s, Lehn and co
Elucidating the glycan-binding specificity and structure of Cucumis melo agglutinin, a new R-type lectin
Beilstein J. Org. Chem. 2024, 20, 306–320, doi:10.3762/bjoc.20.31
- assigned binding motif is shown with added transparency. Full array data are available in Supporting Information File 1, tables “cfg” and “imperial”. (c) Enrichment analysis of glycan array data. For both NCFG and ICL array data, we used the get_pvals_motif function from glycowork [24] (version 0.8.1) with
Synthesis of ether lipids: natural compounds and analogues
Beilstein J. Org. Chem. 2023, 19, 1299–1369, doi:10.3762/bjoc.19.96
Non-peptide compounds from Kronopolites svenhedini (Verhoeff) and their antitumor and iNOS inhibitory activities
Beilstein J. Org. Chem. 2023, 19, 789–799, doi:10.3762/bjoc.19.59
- digestion solution, ground, and centrifuged to produce a cell suspension. Lymphocytes were isolated from the cell suspension using the Percoll method and were further enriched (via negative selection) to obtain naive CD8+ T cells. The enrichment effect and phenotype of the CD8+ cells were detected by flow
Chemistry of polyhalogenated nitrobutadienes, 17: Efficient synthesis of persubstituted chloroquinolinyl-1H-pyrazoles and evaluation of their antimalarial, anti-SARS-CoV-2, antibacterial, and cytotoxic activities
Beilstein J. Org. Chem. 2022, 18, 524–532, doi:10.3762/bjoc.18.54
- test systems, show EC50 values in the lower nM range [36][37][38][39]. Thus, the newly reported compounds are a valuable enrichment from the chemical perspective and have promising potential for further optimization or combination with other compounds. The structures of chloroquine, hydroxychloroquine
Enantioselective PCCP Brønsted acid-catalyzed aminalization of aldehydes
Beilstein J. Org. Chem. 2021, 17, 2433–2440, doi:10.3762/bjoc.17.160
- substituent on the aromatic ring was investigated. The position of bromine on the aromatic ring had a dramatic effect on the enantiomeric purity of the formed products 3k–n. When a bromine substituent is introduced in the “3” position of anthranilamide, the enantiomeric enrichment of aminal 3k reached only 30
Halides as versatile anions in asymmetric anion-binding organocatalysis
Beilstein J. Org. Chem. 2021, 17, 2270–2286, doi:10.3762/bjoc.17.145
- complex or active nucleophiles. In 2014, Jacobsen et al. developed a highly enantioselective selenocyclization reaction of olefins 26, using the chiral squaramide 28 as a dual hydrogen bond donor (Scheme 6) [16]. Although early-stage enantio-enrichment during the introduction of selenium is hard to
A systems-based framework to computationally describe putative transcription factors and signaling pathways regulating glycan biosynthesis
Beilstein J. Org. Chem. 2021, 17, 1712–1724, doi:10.3762/bjoc.17.119
- additional plots provided for additional cancer types in Supporting Information File 1 for luminal breast cancer. CREB3L4 and PRDM1 disproportionately affect the type I and II LacNAc pathway in luminal breast cancer: Our analysis suggests that CREB3L4 (enrichment p-value = 0.036) and PRDM1 (enrichment p
- directly impacted by TGF-β signaling, and thus increasing the metastatic potential of cancer [28]. MEF2C was found to be inhibited by MECP2 based on Reactome pathway enrichment. Since the glycosaminoglycan elongation pathways positively correlate to MEFC2 expression and MEFC2 is amplified in cancer, it is
- sulfate chain elongation: The MECP2 (enrichment p-value = 0.037) was found to positively regulate heparan sulfate elongation. MECP2 regulates gene expression by binding to methylated promoters and then by recruiting chromatin remodeling proteins to condense DNA and repress gene expression [29][30]. MECP2
Volatile emission and biosynthesis in endophytic fungi colonizing black poplar leaves
Beilstein J. Org. Chem. 2021, 17, 1698–1711, doi:10.3762/bjoc.17.118
- library was prepared, and PolyA enrichment was performed before sequencing on an IlluminaHiSeq 3000 sequencer (Max Planck Genome Centre, Cologne, Germany) with 25 Mio reads, 150 base pairs, paired end. Trimming of the obtained Illumina reads and de novo assembly were both performed with the program CLC
Chemical approaches to discover the full potential of peptide nucleic acids in biomedical applications
Beilstein J. Org. Chem. 2021, 17, 1641–1688, doi:10.3762/bjoc.17.116
Photoinduced post-modification of graphitic carbon nitride-embedded hydrogels: synthesis of 'hydrophobic hydrogels' and pore substructuring
Beilstein J. Org. Chem. 2021, 17, 1323–1334, doi:10.3762/bjoc.17.92
- ). After the polymerization was completed, polymer networks were purified as delineated in the experimental section. Altered pore morphology was investigated by SEM, and functional group analysis was achieved by FTIR. Enrichment of the hydrogel network with subsequent radical polymerization using various
Enhanced target cell specificity and uptake of lipid nanoparticles using RNA aptamers and peptides
Beilstein J. Org. Chem. 2021, 17, 891–907, doi:10.3762/bjoc.17.75
- exponential enrichment (SELEX) [30]. SELEX is an iterative process that begins with a large oligonucleotide library that, through a process of negative and positive selections, ends with a few candidates that are specific for a particular protein [30][31]. Using HIV-1 as our model, we explored the use of two
α,γ-Dioxygenated amides via tandem Brook rearrangement/radical oxygenation reactions and their application to syntheses of γ-lactams
Beilstein J. Org. Chem. 2021, 17, 688–704, doi:10.3762/bjoc.17.58
- did not improve the results, indicating that the reactions are at thermodynamic equilibrium after 24 h. Surprisingly, for N-methyl-substituted lactam 12e the diastereomeric enrichment remained rather moderate despite variations of temperature and time (Table 4, entry 5), whereas the diastereomeric
Semiautomated glycoproteomics data analysis workflow for maximized glycopeptide identification and reliable quantification
Beilstein J. Org. Chem. 2020, 16, 3038–3051, doi:10.3762/bjoc.16.253
- abundance of the individual proteins. For addressing these ambiguities, a more selective sample preparation is required, for example, using different enrichment strategies or proteases [23]. Interestingly, an additional allotype of the main IgG3 glycosylation site (EEQYNSTFR) was assigned in four out of
- Ultra system (Veolia Water Technologies Netherlands B.V., Ede, Netherlands). Sequencing-grade trypsin was obtained from Promega (Madison, WI). Sample preparation A detailed description of the methods for the immunoaffinity enrichment of the immunoglobulins and the glycopeptide preparation can be found
Dirhamnolipid ester – formation of reverse wormlike micelles in a binary (primerless) system
Beilstein J. Org. Chem. 2020, 16, 2820–2830, doi:10.3762/bjoc.16.232
- ingredients in a lot of technical applications. They can act as a flotation agent in the enrichment of ores [1], emulsifier and stabilizer for emulsions [2], or as additives for self-cleaning surfaces (artificial lotus effect) [3][4]. Rhamnolipids (RL, Figure 1) are biosurfactants, that are produced by
Synthesis of purines and adenines containing the hexafluoroisopropyl group
Beilstein J. Org. Chem. 2020, 16, 2739–2748, doi:10.3762/bjoc.16.224
- equivalent of elemental sulfur (Scheme 1). A crude mixture of 2a and 2b (ratio 70:30) was isolated in 78% yield. Since the minor isomer 2b had a significantly higher solubility in hexane, washing of the crude mixture with hexane resulted in an enrichment of the major isomer 2a (ratio 2a/2b 95:5 after washing
GlypNirO: An automated workflow for quantitative N- and O-linked glycoproteomic data analysis
Beilstein J. Org. Chem. 2020, 16, 2127–2135, doi:10.3762/bjoc.16.180
- proteomic sample preparation and protease digestion, coupled with depletion of abundant proteins or enrichment of glycopeptides to enable their measurement. There have also been several advances in glycopeptide quantification strategies including chemical labelling, label-free and data-independent
4-Hydroxy-3-methyl-2(1H)-quinolone, originally discovered from a Brassicaceae plant, produced by a soil bacterium of the genus Burkholderia sp.: determination of a preferred tautomer and antioxidant activity
Beilstein J. Org. Chem. 2020, 16, 1489–1494, doi:10.3762/bjoc.16.124
- providing sufficient evidence to support the structure, was isolated from a fermentation extract of Burkholderia sp. 3Y-MMP isolated from a soil by a Zn2+ enrichment culture. Detailed spectroscopic analyses by MS and NMR, combined with 13C chemical shift comparison with literature values of the related
- in the host organisms. Keywords: antioxidant; Burkholderia sp; quinolone; soil bacterium; Zn2+ enrichment culture; Findings 4-Hydroxy-2(1H)-quinolone (3) is a unique structural motif mostly found in alkaloids from rutaceous plants (family Rutaceae) [1][2]. This motif has several tautomeric forms
- secondary metabolism [15]. In the course of our continuing studies on bioactive metabolites of less studied bacterial taxa [16], Burkholderia sp. 3Y-MMP, isolated from soil by an exhaustive enrichment culture under Zn2+-load, was selected for a detailed chemical study, which resulted in the isolation of 4
Activated carbon as catalyst support: precursors, preparation, modification and characterization
Beilstein J. Org. Chem. 2020, 16, 1188–1202, doi:10.3762/bjoc.16.104
- of oxygen surface groups depending on the oxidizing agent. Oxidative treatment with liquid agents (HNO3 or H2O2) increases the amount of carboxylic groups, while carbonyl and hydroxy surface groups result from modification with O2 or N2O [110]. Nitrogen-containing surface groups: Nitrogen-enrichment
- different elemental compositions of the bituminous coal based materials after carbonization, activation and ammoxidation for the enrichment of nitrogen. He found that the carbonization step causes an increase of the carbon content, a decrease of oxygen and hydrogen and the nitrogen amount stays almost
- constant. The activation process leads to an increase of oxygen, while all other elements decrease. Thus, the activation reagent (KOH) oxidizes the initial material during this step. As expected, the ammoxidation results in an enrichment of nitrogen [10]. Scanning electron microscopy with energy-dispersive
A smart deoxyribozyme-based fluorescent sensor for in vitro detection of androgen receptor mRNA
Beilstein J. Org. Chem. 2020, 16, 1135–1141, doi:10.3762/bjoc.16.100
- random sequence molecules, also known as SELEX (systematic evolution of ligands by exponential enrichment), and was a holistic harpin [22]. In further work MGA was separated into two strands, and nucleic acid binding arms were added to each strand, allowing MGA to target a sequence of interest
[1,3]/[1,4]-Sulfur atom migration in β-hydroxyalkylphosphine sulfides
Beilstein J. Org. Chem. 2020, 16, 88–105, doi:10.3762/bjoc.16.11
- ]-rearrangement proceeded with additional partial enrichment of one enantiomer. The latter may have occurred through the preferential acylation of one of two diastereoisomers under the reaction conditions where the second chirality center at the phosphorus atom influenced the ratio of the acylation reaction. With
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