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Search for "lipid" in Full Text gives 154 result(s) in Beilstein Journal of Organic Chemistry.
Progress and challenges in the synthesis of sequence controlled polysaccharides
Beilstein J. Org. Chem. 2021, 17, 1981–2025, doi:10.3762/bjoc.17.129
Asymmetric organocatalyzed synthesis of coumarin derivatives
Beilstein J. Org. Chem. 2021, 17, 1952–1980, doi:10.3762/bjoc.17.128
- hydroquinolinone, chromene, piperidine, peptide, lipid, and glycoside moieties (Scheme 2). Bojanowski and co-workers developed a methodology to synthetize 3,4-dihydrocoumarins 10 through a decarboxylative and dearomatizative cascade reaction [33]. This reaction was carried out using coumarin-3-carboxylic acids 8
On the application of 3d metals for C–H activation toward bioactive compounds: The key step for the synthesis of silver bullets
Beilstein J. Org. Chem. 2021, 17, 1849–1938, doi:10.3762/bjoc.17.126
Cationic oligonucleotide derivatives and conjugates: A favorable approach for enhanced DNA and RNA targeting oligonucleotides
Beilstein J. Org. Chem. 2021, 17, 1828–1848, doi:10.3762/bjoc.17.125
- ]. Notably, optimization of the therapeutic window of ASOs is closely related to improved delivery, and a variety of chemical strategies have been investigated in this context, such as ASO–lipid conjugates for improved endosomal escape [21], ASO–triantennary N-acetylgalactosamine (GalNAc) conjugates for
Natural products in the predatory defence of the filamentous fungal pathogen Aspergillus fumigatus
Beilstein J. Org. Chem. 2021, 17, 1814–1827, doi:10.3762/bjoc.17.124
- ACAT2 and renders it inactive [173]. In vivo, PPPA-mediated ACAT2 inhibition was shown to protect the mice from atherosclerosis, ACAT2 enzyme mediates in lipid metabolism and is localized in the liver and intestines [174]. Furthermore, PPPA was also shown to exhibit insecticidal properties against
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
- various sources in literature [45][46]. The following is a summary of the pathways studied and the enzymes involved: 1) Glycolipid core: The enzymes in this group are involved in the biosynthesis of the glucosylceramide (GlcCer) and galactosylceramide (GalCer) lipid core. Here, the GlcCer core is formed
- extension: This pathway includes glycogenes responsible for the synthesis of GPI-anchored proteins in the ER. This involves the synthesis of a glycan–lipid precursor that is en bloc transferred to proteins. 13) O-Mannose: This is initiated by the addition of mannose to Ser/Thr using POMT1 or POMT2. β1-2 or
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
- phosphono-PNAs retained the stability against nucleases. In another study, conjugation with glutamine phosphonate or lysine bis-phosphonate amino acid derivatives introduced up to twelve negative charges (phosphonate moieties) into PNAs [91]. The negative charges allowed cationic lipid-mediated delivery of
Structural effects of meso-halogenation on porphyrins
Beilstein J. Org. Chem. 2021, 17, 1149–1170, doi:10.3762/bjoc.17.88
- interesting example of the effects that long alkyl chains have on the overall packing. This is seen as the preferred alignment of alkyl chain with each other, reminiscent of a lipid bilayer (Supporting Information File 1, Figure S32) [23]. There are four motifs that contribute to the overall packing seen in
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
- Lipid nanoparticles (LNPs) constitute a facile and scalable approach for delivery of payloads to human cells. LNPs are relatively immunologically inert and can be produced in a cost effective and scalable manner. However, targeting and delivery of LNPs across the blood–brain barrier (BBB) has proven
- challenging. In an effort to target LNPs composed of an ionizable cationic lipid (DLin-MC3-DMA), cholesterol, the phospholipid 1,2-distearoyl-sn-glycero-3-phosphocholine (DSPC), and 1,2-dimyristoyl-rac-glycero-3-methoxypolyethylene glycol-2000 (DMG-PEG 2000) to particular cell types, as well as to generate
- the usefulness of aptamer-loaded LNPs to increase target cell specificity and potentially deliverability of central-nervous-system-active RNAi therapeutics across the BBB. Keywords: aptamer; blood–brain barrier; gene therapy; HIV-1; lipid nanoparticle; Introduction Lipid nanoparticles (LNPs
Metal-free visible-light-enabled vicinal trifluoromethyl dithiolation of unactivated alkenes
Beilstein J. Org. Chem. 2021, 17, 551–557, doi:10.3762/bjoc.17.49
- (πR = 1.44), compared with CF3 (πR = 0.88) and SCH3 (πR = 0.61), which could improve the pharmaceuticals’ ability to cross lipid membranes [9][10]. Along these lines, the introduction of the SCF3 group into small molecules has attracted great attention in organofluorine methodology [11][12][13][14][15
Synthesis and physicochemical evaluation of fluorinated lipopeptide precursors of ligands for microbubble targeting
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
- serine–glycine (SG)n segments rather than classical poly(oxyethylene) linkers between the lipid polar head and a targeting ligand were proposed for the liposome-mediated, selective delivery of anticancer drugs. Here, we report the synthesis of perfluoroalkylated lipopeptides (F-lipopeptides) bearing two
- particular cell surface receptor [7][9][10][11][12][13][14]. To this aim, ligand–lipid conjugates have been developed in research and preclinical development for liposome targeting for decades. In particular, peptide ligands offer significant advantages, including efficient synthesis routes, versatility, and
Biochemistry of fluoroprolines: the prospect of making fluorine a bioelement
Beilstein J. Org. Chem. 2021, 17, 439–460, doi:10.3762/bjoc.17.40
19F NMR as a tool in chemical biology
Beilstein J. Org. Chem. 2021, 17, 293–318, doi:10.3762/bjoc.17.28
- their NMR study on lipid bicelles (Figure 2) [15]. In contrast to more traditional amino acids, such as 1–4, the perfluorinated tert-butyl moiety in 8 has nine equivalent fluorine atoms and no coupled hydrogens, so it gives rise to a characteristic high intensity 19F NMR singlet. As shown by the authors
- nuclei such as 1H or 15N PREs. 19F NMR has also been applied to study the conformational heterogeneity and dynamics of a broad range of proteins and peptides upon their interaction with model lipid vesicles [59], micelles [60] and bicelles [61]. It has enabled the quantification and mechanistic
Molecular basis for protein–protein interactions
Beilstein J. Org. Chem. 2021, 17, 1–10, doi:10.3762/bjoc.17.1
- known as a capsid [78]. Some viruses also have lipid envelopes containing glycoproteins, which interact with the host cell membrane to facilitate the viral entry into the cell [79]. The simplest explanation for viral capsid assembly is protein assembly units colliding (following Brownian motion) in a
Secondary metabolites of Bacillus subtilis impact the assembly of soil-derived semisynthetic bacterial communities
Beilstein J. Org. Chem. 2020, 16, 2983–2998, doi:10.3762/bjoc.16.248
- surfactin bioactivity is specifically evoked by the surfactant activity triggering cell lysis due to penetration of the bacterial lipid bilayer membranes and the formation of ion-conducting channels [40][41][42]. The bioactivity of surfactin was shown against Listeria spp. and Legionella monocytogenes [43
Selected peptide-based fluorescent probes for biological applications
Beilstein J. Org. Chem. 2020, 16, 2971–2982, doi:10.3762/bjoc.16.247
- bacteria [57]. It is a glycolipid consisting of a variable polysaccharide domain connected to a conserved glucosamine-based phospholipid called lipid A. It is highly negatively charged due to two phosphorylated groups in the lipid A part and carboxylated groups in the polysaccharide part. It is amphiphilic
- for the turn on fluorescent detection of LPS in mixed solvent (DMSO/TBS buffer, 1:4) (Figure 10A) [59]. The liposomes are created by mixing two lipids in a ratio of 9:1. First lipid 12 is designed by attaching 10,12-tricosadiyonic acid to a penta-lysine oligopeptide bearing an aminonaphthalimide
- fluorophore on one lysine. The four cationic lysine residues are closely mimicking the structure of polymyxin B, which has a strong affinity to the negative LPS. The second lipid 13 is designed by connecting 10,12-tricosadiyonic acid to histidine. PDA liposomes are formed after UV-light-irradiated
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
- . Results and Discussion Materials and synthesis of dirhamnolipid ester The used dirhamnolipid raw material stems from a biotechnological process. The purity is 90.8% with respect to the rhamnolipid acid form. Due to the biotechnological production, the alkyl chain length in the lipid part varies from C8 to
Easy access to a carbohydrate-based template for stimuli-responsive surfactants
Beilstein J. Org. Chem. 2020, 16, 2788–2794, doi:10.3762/bjoc.16.229
- -delivery system owing to their size and the ability to carry drugs, both in the polar (core) or apolar (lipid bilayer) interior [4][5]. A challenge in liposome-based drug delivery systems is to release the drug at the place of function. This challenge has led to the development of stimuli-responsive
- mechanical impulse that can increase or decrease the distance between the two lipophilic tails, thus changing the amphiphilic properties of the molecule. Incorporating such molecules into the lipid bilayer of liposomes can result in the decomposition of the whole liposome when the stimuli-responsive
A consensus-based and readable extension of Linear Code for Reaction Rules (LiCoRR)
Beilstein J. Org. Chem. 2020, 16, 2645–2662, doi:10.3762/bjoc.16.215
- regulate that amino acid sequences are written after “ ; ”, lipid moieties are written after “ : ”, and other glycosides are written after “ # ” (GR1). For example, a glucose β-linked to a Ceramide is written as “Gb:C.” Uncertainty rules describe syntax for when certain features of the SU are unknown or
- . However, “ | ” was originally designed to separate the certain and uncertain parts in a fragmented glycan, where there is a possibility of different structures (UR6). Ambiguous symbol 3 – “ # ”. Originally, “ # ” was designated to signify the starting point of glycosides that are not amino acids or lipid
Synthesis of monophosphorylated lipid A precursors using 2-naphthylmethyl ether as a protecting group
Beilstein J. Org. Chem. 2020, 16, 1955–1962, doi:10.3762/bjoc.16.162
- Chemistry, University of South Carolina Lancaster, 476 Hubbard Drive, Lancaster, South Carolina 29720, USA, Suzhou Jingye Medicine & Chemical Co., Ltd, 88 Sanlian Street, Suzhou, Jiangsu Province, 215129, China 10.3762/bjoc.16.162 Abstract Lipid A, the hydrophobic domain of lipopolysaccharide (LPS), is a
- strong immunostimulator and therefore a valuable target for the development of novel immunomodulators. Various lipid A derivatives have been chemically synthesized in order to reduce toxicity while retaining the immunostimulatory activity. In this work, we describe a novel approach to the frequently
- problematic synthesis of monophosphorylated mono- and disaccharide lipid X using a combination of established chemistry and a novel 2-naphthylmethyl ether (Nap) protecting group for “permanent” protection of hydroxy groups. Of particular note is the fact that the key Nap protecting group is able to remain in
Synthesis, docking study and biological evaluation of ᴅ-fructofuranosyl and ᴅ-tagatofuranosyl sulfones as potential inhibitors of the mycobacterial galactan synthesis targeting the galactofuranosyltransferase GlfT2
Beilstein J. Org. Chem. 2020, 16, 1853–1862, doi:10.3762/bjoc.16.152
- decaprenyl-P-P-GlcNAc-Rha, (glycolipid 2, GL2), which serves as a lipid carrier for arabinogalactan polymerization [7][8]. The latter enzyme, GlfT2, extends the product of GlfT1-catalyzed reaction, decaprenyl-P-P-GlcNAc-Rha-Galf2 (glycolipid 4, GL4), producing the lipid-linked galactan polymer [8]. Both
- obtained by acetonide hydrolysis under acidic conditions followed by the final catalytic hydrogenation of the benzyl protecting groups in derivatives 22. Evaluation of the effects of the target compounds on the synthesis of lipid-linked galactan precursors The availability of a series of compounds with
- -up of lipid-linked galactan precursors. The crude enzymes used in the assay allow for in situ synthesis of the acceptor for galactan polymerization, decaprenyl-P-P-GlcNAc-Rha (GL2), from endogenous decaprenyl phosphate and sugar nucleotides UDP-GlcNAc and TDP-Rha supplied in the reaction mixture
Nonenzymatic synthesis of anomerically pure, mannosyl-based molecular probes for scramblase identification studies
Beilstein J. Org. Chem. 2020, 16, 1732–1739, doi:10.3762/bjoc.16.145
- moiety for photocrosslinking to MPD-recognizing proteins. The presence of an additional propargyl group provides a way to further derivatize the probe with biotin azide via click-type chemistry [16] for the isolation of protein–lipid adducts using streptavidin resins [10]. To synthesize such molecular
- )-labeled analog MPC-2 carries an additional dodecanyl linker between the citronellyl unit and the fluorophore. This is intended to increase the hydrophobic interactions between the probe and the lipid bilayer and also to increase the flexibility. More specifically, the probe should adopt a U-shaped
- Financial support by the Swiss National Science Foundation (SNSF) is gratefully acknowledged: This research was funded by the Sinergia Project: Molecular identification of lipid transporters for protein glycosylation, Grant CRSII5_170923.
Two antibacterial and PPARα/γ-agonistic unsaturated keto fatty acids from a coral-associated actinomycete of the genus Micrococcus
Beilstein J. Org. Chem. 2020, 16, 297–304, doi:10.3762/bjoc.16.29
- key roles in lipid and carbohydrate metabolism [43][44]. PPARα upregulates lipid uptake and β-oxidation of fatty acids, whereas PPARγ promotes adipocyte differentiation and adipokine production in adipose tissues to improve insulin sensitivity in diabetic patients [45][46][47]. Owing to these
Potent hemithioindigo-based antimitotics photocontrol the microtubule cytoskeleton in cellulo
Beilstein J. Org. Chem. 2020, 16, 125–134, doi:10.3762/bjoc.16.14
- nm), photoswitching could not be observed either, which we presumed to be due to fast thermal relaxation. However, noting that typical CDIs are substantially biolocalised into lipid environments within cells [31], we decided to explore photoswitching-based cellular assays with these compounds
- dark conditions (λ = 450 nm). This difference was surprisingly high, given that even in aprotic media (e.g., lipid environment reservoirs within cells), there should be ca. 30% residual Z-isomer at photoequilibrium [18], and we had expected that any (E)-HITub entering the cytosol (aqueous environment
Synthesis of C-glycosyl phosphonate derivatives of 4-amino-4-deoxy-α-ʟ-arabinose
Beilstein J. Org. Chem. 2020, 16, 9–14, doi:10.3762/bjoc.16.2
- derivatives. These intermediates will be of value for their future conversion into transition state analogues as well as for the introduction of various lipid extensions at the anomeric phosphonate moiety. Keywords: antibiotic resistance; glycosyl phosphonate; glycosyl transferase; lipid A
- ; lipopolysaccharide; Introduction Glycosyltransferases are important enzymes that accomplish the transfer of activated sugar phosphates onto their respective acceptor molecules [1]. In most cases, nucleotide diphosphate sugars serve as the reactive species, but lipid-linked diphosphate derivatives are equally
- mechanisms of pathogenic Gram-negative bacteria against antibiotics, such as polymyxin B and colistin [3]. The main effect of Ara4N incorporation into the lipid A part – and, less frequently, into the inner core region of LPS [4] – is thought to originate from blocking the electrostatic interaction of
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