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Search for "micelles" in Full Text gives 82 result(s) in Beilstein Journal of Organic Chemistry.
Ammonium-tagged ruthenium-based catalysts for olefin metathesis in aqueous media under ultrasound and microwave irradiation
Beilstein J. Org. Chem. 2019, 15, 160–166, doi:10.3762/bjoc.15.16
- in the flourishing field of micellar catalysis and the use of surfactants that self-aggregate in water into micelles in which the hydrophobic core provides an environment for effecting homogeneous reactions between organic molecules has been reviewed by Scarso et al. [40] and very recently by
Green synthesis of new chiral 1-(arylamino)imidazo[2,1-a]isoindole-2,5-diones from the corresponding α-amino acid arylhydrazides in aqueous medium
Beilstein J. Org. Chem. 2018, 14, 2923–2930, doi:10.3762/bjoc.14.271
- surfactants that can form micelles with a hydrophobic core and a hydrophilic corona. (iii) This clean method afforded compounds 5a–m without the need of additional purification such as column chromatography or recrystallization. (iv) The use of a sealed tube [36][37][38][39][40][41][42][43] obeys to four out
Synthesis of new p-tert-butylcalix[4]arene-based polyammonium triazolyl amphiphiles and their binding with nucleoside phosphates
Beilstein J. Org. Chem. 2018, 14, 1980–1993, doi:10.3762/bjoc.14.173
- ratio of the intensities of the first and third bands (373 and 384 nm, respectively) in its emission spectrum [40]. EY, an anionic xanthene dye, also can be used for CAC determination as its absorption spectrum shows a shift of the maximum absorption wavelength (λmax) in the presence of micelles or
A survey of chiral hypervalent iodine reagents in asymmetric synthesis
Beilstein J. Org. Chem. 2018, 14, 1244–1262, doi:10.3762/bjoc.14.107
- asymmetric oxidations were examined in 20 mol % cetyltrimethylammonium bromide (CTAB) reversed micelles [25]. Interestingly, Varvoglis et al. synthesized another new class of a chiral reagent 3 using (+)-camphor sulfonic acids as the source of chirality [26] which was used by Chen et al. for the oxidation of
Crystal structure of the inclusion complex of cholesterol in β-cyclodextrin and molecular dynamics studies
Beilstein J. Org. Chem. 2018, 14, 838–848, doi:10.3762/bjoc.14.69
- increased safety in NPC animal models [12]. Moreover, superstructures of cyclodextrins like mono-lactose-appended β-CD [13] and biocleavable pluronic/β-CD-based polyrotaxanes [14] as well as PEG-lipid micelles (DSPE-PEG) in combination with HP-β-CD [15] have shown enhanced therapeutic effects and exhibit a
Nanoreactors for green catalysis
Beilstein J. Org. Chem. 2018, 14, 716–733, doi:10.3762/bjoc.14.61
- , namely: (polymer) vesicles, micelles, dendrimers and nanogels. The ability and efficiency of catalytic nanoreactors to carry out organic reactions in water, to perform cascade reaction and their ability to be recycled will be discussed. Keywords: catalysis; dendrimers; green chemistry; nanogels
- ; nanoreactors; micelles; polymersomes; Introduction It is widely acknowledged that “the best solvent is no solvent”; however, running a reaction under neat conditions is very challenging from the points of view of mass transfer and temperature gradients [1][2]. Therefore, sustainable chemical technologies are
- more achievable. Nanocompartments such as polymersomes [40], micelles [41], dendrimers [42], and nanogels [43][44] represent smart and compact devices to carry out reactions in aqueous media. Besides, their facile recyclability make them very suitable as nanoreactors for a multitude of applications in
Latest development in the synthesis of ursodeoxycholic acid (UDCA): a critical review
Beilstein J. Org. Chem. 2018, 14, 470–483, doi:10.3762/bjoc.14.33
- plane, defining a structure in which the molecule has a polar and an apolar surface. For this reason, these molecules and their derivatives are defined as amphipathic. Bile acids are considered very important molecules for their ability to form micelles in an aqueous environment [22]. Bile acids
- . In addition, at higher concentrations than the critical micelles concentration (CMC), bile acids tend to form micelles: this phenomenon, due to the amphipathic structure of these molecules, is limiting the availability of free hydroxysteroids in solution. The reported CMCs of bile acids are in the
Binding abilities of a chiral calix[4]resorcinarene: a polarimetric investigation on a complex case of study
Beilstein J. Org. Chem. 2017, 13, 2698–2709, doi:10.3762/bjoc.13.268
- [31][32], for instance as chiral selectors or as catalysts in micro-heterogeneous or organized systems (micelles, Langmuir–Blodgett films, ionic liquids etc.). Finally, our study shows how the use of polarimetry, which has already been shown a powerful tool for the systematic study of the binding
Synthesis and supramolecular properties of regioisomers of mononaphthylallyl derivatives of γ-cyclodextrin
Beilstein J. Org. Chem. 2017, 13, 2509–2520, doi:10.3762/bjoc.13.248
- and γ-CD/γ-CD. In Figure 10 various putative interactions of NA-γ-CD are schematically depicted indicating how small supramolecular structures such as supramolecular oligomers or micelles as well as large one such as aggregates can originate. As all three NA-γ-CD regioisomers were prepared, the effect
2-Methyl-2,4-pentanediol (MPD) boosts as detergent-substitute the performance of ß-barrel hybrid catalyst for phenylacetylene polymerization
Beilstein J. Org. Chem. 2017, 13, 1498–1506, doi:10.3762/bjoc.13.148
- rhodium-based biohybrid catalyst. Unlike commonly used detergents such as sodium dodecyl sulfate or polyethylene polyethyleneglycol, MPD does not form micelles in solution. Molecular dynamics simulations revealed the effect and position of stabilizing MPD molecules. The advantage of the amphiphilic MPD
- membrane protein solubilization, but is leading to protein unfolding as a drawback. Disadvantageous of detergents is the tremendous reduction of selectivity due to denaturing the protein or the reduction of productivity by detergent micelles since hydrophobic compounds are most likely located inside the
- refolding reagent PE–PEG. The isolated yield increased from 5% to 52%. This is related to the increased FhuA ΔCVFtev stability in the presence of hydrophobic substrates. The hydrophobic phenylacetylene interacts with the micelles formed by the PE–PEG refolding reagent, causing the protein precipitation
Framing major prebiotic transitions as stages of protocell development: three challenges for origins-of-life research
Beilstein J. Org. Chem. 2017, 13, 1388–1395, doi:10.3762/bjoc.13.135
- most of us working in the ‘protocell camp’ make [12][13][14][15][16]. Under this general hypothesis, one can distinguish two major avenues of research. According to the first, organic compartments of different types (micelles or other colloidal structures) would initially play the role of harbouring
Correlation of surface pressure and hue of planarizable push–pull chromophores at the air/water interface
Beilstein J. Org. Chem. 2017, 13, 1099–1105, doi:10.3762/bjoc.13.109
- ]. Mechanical planarization in the ground state increases the conjugation of the push–pull system. As a result, the excitation (or absorption) maximum shifts up to 80 nm to the red [8]. An anionic headgroup is added to produce an amphiphile that self-assembles into monolayers and micelles and enters
Glyco-gold nanoparticles: synthesis and applications
Beilstein J. Org. Chem. 2017, 13, 1008–1021, doi:10.3762/bjoc.13.100
- comparison to other glycoclusters, i.e., glycolipid micelles and glycoproteins, which allows an ordered, controlled and stable tridimensional presentation of the ligands, providing higher ligand binding capacity [6][96]. For this reason, they represent an ideal scaffold to study the activation of the immune
Aggregation behaviour of a single-chain, phenylene-modified bolalipid and its miscibility with classical phospholipids
Beilstein J. Org. Chem. 2017, 13, 995–1007, doi:10.3762/bjoc.13.99
- flexible nanofibres at 27 °C and further to small elongated micelles at 45 °C. Furthermore, the miscibility of the bolalipid with bilayer-forming phosphatidylcholines (DMPC, DPPC, and DSPC) was investigated by means of DSC, TEM, FTIR, and small angle X-ray scattering (SAXS). We could show that the PC
- simulations [27]. A temperature increase leads to a transformation of the nanofibres into small micelles and the gel character is lost. This reversible gel/sol transformation is accompanied by a cooperative endothermic transition at Tm = 48 °C, which can be followed by differential scanning calorimetry (DSC
- -C16pPhC16-PC [36], which self-assembles at room temperature into small ellipsoidal micelles, and to PC-C17pPhC17-PC [35] that forms nanofibres with a significantly reduced thermal stability compared to PC-C32-PC. Unfortunately, the insertion of PC-C17pPhC17-PC into phospholipid bilayers composed of, e.g
Expression, purification and structural analysis of functional GABA transporter 1 using the baculovirus expression system
Beilstein J. Org. Chem. 2017, 13, 874–882, doi:10.3762/bjoc.13.88
- contains only a low amount of the GAT1/GFP protein that exits partly in an aggregated form (Figure S4, Supporting Information File 1). Some noticeable small particles with high contrast were observed. The radius of DDM micelles has been reported to be approximately 2.6–3.5 nm [32], however, the observed
- high contrast is not typical for detergent micelles. As it was not clear whether the particles could simply be attributed to spherical micelles control cryo-TEM experiments were performed. Using a Tris-buffered saline (TBS) solution containing 0.05% DDM (which is far above the critical micellar
- concentration (CMC) of DDM:0.009% or 0.18 mM), no significant population of micelles could be found. These results suggest that the observed particles most likely correspond to a monodisperse preparation of GAT1/GFP. Several studies have demonstrated that GAT1 expresses in an oligomeric formation in the plasma
Formose reaction accelerated in aerosol-OT reverse micelles
Beilstein J. Org. Chem. 2016, 12, 2663–2667, doi:10.3762/bjoc.12.262
- Makoto Masaoka Tomohiro Michitaka Akihito Hashidzume Department of Macromolecular Science, Graduate School of Science, Osaka University, 1-1 Machikaneyama-cho, Toyonaka, Osaka 560-0043, Japan 10.3762/bjoc.12.262 Abstract The formose reaction in reverse micelles of aerosol-OT (AOT), triton X-100
- (TX), and hexadecyltrimethylammonium bromide (CTAB) was investigated. Time–conversion data have indicated that the interfacial water layer of AOT reverse micelles is a medium that accelerates formation of glycolaldehyde in the formose reaction. The 13C NMR spectra for the products of the formose
- reaction using formaldehyde-13C as starting material are indicative of the formation of ethylene glycol as a major product. Keywords: aerosol-OT; formose reaction; hexadecyltrimethylammonium bromide; interfacial layer; reverse micelles; triton X-100; water pool; Findings The ‘formose reaction’ yields a
Stimuli-responsive HBPS-g-PDMAEMA and its application as nanocarrier in loading hydrophobic molecules
Beilstein J. Org. Chem. 2016, 12, 939–949, doi:10.3762/bjoc.12.92
- fluorescence intensity of the peaks around 625 nm as a function of the concentration of HBPE-g-PDMAEMA aggregates, and it was found that a large amount of NR was dispersed in water with more HBPE-g-PDMAEMA aggregates. The trend was nonlinear unlike the linear trend of NR encapsulation in micelles, as the size
Muraymycin nucleoside-peptide antibiotics: uridine-derived natural products as lead structures for the development of novel antibacterial agents
Beilstein J. Org. Chem. 2016, 12, 769–795, doi:10.3762/bjoc.12.77
- the PNPT superfamily. MraYAA crystallised as a dimer and additional experiments showed that it also exists as a dimer in detergent micelles and membranes [71]. The previously proposed models are in agreement with the solved structure showing ten transmembrane helices and five cytoplasmic loops. The
Nucleic acids through condensation of nucleosides and phosphorous acid in the presence of sulfur
Beilstein J. Org. Chem. 2016, 12, 670–673, doi:10.3762/bjoc.12.67
- , solubilization by micelles [14][15] or a prebiotic oil slick [16] appears a more plausible scenario [17]. Results and Discussion Preparation of phosphorothioate oligonucleotides Equimolar amounts of thymidine and aq triethylammonium phosphite and a fourfold excess of S8 were suspended in toluene. The mixture was
Recent advances in N-heterocyclic carbene (NHC)-catalysed benzoin reactions
Beilstein J. Org. Chem. 2016, 12, 444–461, doi:10.3762/bjoc.12.47
- aliphatic side chains was used by Iwamoto and co-workers for promoting benzoin reactions in aqueous medium. The improved reactivity was attributed to the formation of micelles from the hydrophobic alkyl chains of the catalyst in aqueous medium. The reaction proceeded well with various aromatic and
Supramolecular polymer assembly in aqueous solution arising from cyclodextrin host–guest complexation
Beilstein J. Org. Chem. 2016, 12, 50–72, doi:10.3762/bjoc.12.7
- hydrophobic interactions between PAAodn are restored in the 1:2:1 and 2:2:1 solutions while at higher SDS ratios SDS dominated micelles form which disrupt inter-polymer chain interactions [37][40][51]. Similar additions of SDS to the 2:1 β-CD:n-C18H37 solution restores the hydrophobic interactions between
- hydrogel formed through the initial formation of micelles of poly(ethylene glycol)-b-poly(acrylate), PEG-b-PAA, copolymer and the widely used anticancer drug cis-diamminedichloroplatinum(II), cisplatin [91], and subsequent host–guest complexation by α-CD has been developed by Zhu et al. (Figure 12) [92
- ]. In the first stage, the two chloro ligands on the four-coordinate square-planar platinum(II) center of cisplatin are displaced by PEG-b-PAA carboxylate groups to produce PEG-b-PAA-cisplatin micelles. Addition of α-CD results in host–guest complexation of the PEG segments of PEG-b-PAA and subsequent
Determination of formation constants and structural characterization of cyclodextrin inclusion complexes with two phenolic isomers: carvacrol and thymol
Beilstein J. Org. Chem. 2016, 12, 29–42, doi:10.3762/bjoc.12.5
- phase solubility profiles are generally apparent values that combine several effects on the guest solubility: inclusion complexation, self-association of poorly soluble guests, self-aggregation of CD:guest complexes, as well as non-inclusion interaction and micelles formation [38]. The solubilizing
Recent advances in metathesis-derived polymers containing transition metals in the side chain
Beilstein J. Org. Chem. 2015, 11, 2747–2762, doi:10.3762/bjoc.11.296
- = BPh4 or Cl). Self-assembly of these block copolymers into core–shell spherical micelles was successfully conducted and, by UV/ozonolysis or thermal pyrolysis generating antiferromagnetic CoO species, some of these micelles could be converted into inorganic nanoparticles. With the aim at extending the
- , amphiphilic Ru-modified triblock copolymers have been produced from biocompatible and bioconjugatable oxanorbornene monomers. By extending the above ROMP methodology, Sleiman et al. managed to synthesize the Ru triblock copolymers 25 and 26 (Scheme 11), and examined their self-assembling into micelles in
- copolymer 39 (Scheme 16). Remarkably, in water, this Rh-containing block copolymer readily generated micelles and could be thus successfully employed as a Rh-immobilized catalyst for the hydroformylation of 1-octene. Very recently, Matyjaszewski, Tang and coworkers [62] reported the first synthesis of
Aggregation behaviour of amphiphilic cyclodextrins: the nucleation stage by atomistic molecular dynamics simulations
Beilstein J. Org. Chem. 2015, 11, 2459–2473, doi:10.3762/bjoc.11.267
- molecules or by dispersion interactions at their lateral surface. We suggest that these aggregates can also form the nucleation stage of larger systems as well as the building blocks of micelles, vesicle, membranes, or generally nanoparticles thus opening new perspectives in the design of aggregates
- correlating their structures with the pharmaceutical properties. Keywords: aggregation; amphiphilic cyclodextrins; micelles; molecular dynamics simulations; nanoparticles; self-assembly; Introduction Inclusion complexes with supramolecular structures formed by native or modified cyclodextrins (CDs) are
- modulates the formation of micelles, vesicles, nanospheres (or dense aggregates), and nanocapsules [1]. In particular, non-ionic aCD obtained from β-CD modified with hydrophobic thioalkyl chains (H groups in the following) at the primary rim and short polar PEG oligomers (P groups) at the secondary rim form
Self-assemblies of γ-CDs with pentablock copolymers PMA-PPO-PEO-PPO-PMA and endcapping via atom transfer radical polymerization of 2-methacryloyloxyethyl phosphorylcholine
Beilstein J. Org. Chem. 2015, 11, 2267–2277, doi:10.3762/bjoc.11.247
- -assembled with varying amounts of γ-CDs to prepare poly(pseudorotaxanes) (PPRs). When the concentration of γ-CDs was lower, the central PEO segment served as a shell of the micelles and was preferentially bent to pass through the γ-CD cavity to construct double-chain-stranded tight-fit PPRs characterized by
- a channel-like crystal structure. With an increase in the amount of γ-CDs added, they began to accommodate the poly(methyl acrylate) (PMA) segments dissociated from the core of the micelles. When more γ-CDs were threaded and slipped over the segments, the γ-CDs were randomly distributed along the
- copolymers able to form unique polymeric micelles in aqueous solution before the self-assembly with γ-CDs, as compared to PHEMA-PPO-PEO-PPO-PHEMA. The morphology of self-assembled aggregates of PMA-PPO-PEO-PPO-PMA in aqueous solution was observed by TEM. As shown in Figure S3, Supporting Information File 1
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