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Search for "dendrimer" in Full Text gives 38 result(s) in Beilstein Journal of Organic Chemistry.
Switchable molecular tweezers: design and applications
Beilstein J. Org. Chem. 2024, 20, 504–539, doi:10.3762/bjoc.20.45
Cryogels: recent applications in 3D-bioprinting, injectable cryogels, drug delivery, and wound healing
Beilstein J. Org. Chem. 2021, 17, 2553–2569, doi:10.3762/bjoc.17.171
- implanted. While optimum formulations were identified with the PAMAM dendrimer present, the release of BSP was relatively high within a 24-hour period, indicating that further development is needed to achieve sustained release with this system. After reviewing the recent diverse work currently being
Exfoliated black phosphorous-mediated CuAAC chemistry for organic and macromolecular synthesis under white LED and near-IR irradiation
Beilstein J. Org. Chem. 2021, 17, 2477–2487, doi:10.3762/bjoc.17.164
- has set a milestone as a new and effective method for the synthesis of macromolecules [11]. Initiation of this reaction photocatalytically provides many advantages for the synthetic methodologies including bioconjugation, labeling, surface functionalization, dendrimer synthesis, polymer synthesis, and
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
Supramolecular polymerization of sulfated dendritic peptide amphiphiles into multivalent L-selectin binders
Beilstein J. Org. Chem. 2021, 17, 97–104, doi:10.3762/bjoc.17.10
- to its functionalization with negatively charged sulfate groups. The binding behavior of dPGS to L-selectin has been thoroughly probed as dendrimer [26][27], conjugated to a polymer [28] or as amphiphilic adamantyl conjugates that are able to self-assemble on cyclodextrin vesicles [29]. Our group
An overview on disulfide-catalyzed and -cocatalyzed photoreactions
Beilstein J. Org. Chem. 2020, 16, 1418–1435, doi:10.3762/bjoc.16.118
- oxidation product (Scheme 12). Interestingly, compared to the diphenyl disulfide-catalyzed oxidation, which gives only 23–44% yield, the use of dendrimer disulfides gives the products in much better yields (38–63%). Similar to oxidations, disulfide can also be used as the catalyst to construct functional
- compounds. In the synthesis of these synthons, the key transformation, the isomerization of the trans-1,2-difluorotriethylsilylethylene 57 to the cis isomer 58, is realized with phenyl disulfide under ultraviolet-light irradiation (Scheme 22) [29]. In 2009, Tsuboi and co-workers also reported a dendrimer
- disulfide-catalyzed isomerization of allyl alcohols to carbonyl compounds under high-pressure mercury lamp irradiation (λ > 300 nm) at room temperature. The yield of the reaction reached up to 91% (Scheme 23) [30]. Using the water-soluble dendrimer disulfide, the photoinduced isomerization in water was also
A systematic review on silica-, carbon-, and magnetic materials-supported copper species as efficient heterogeneous nanocatalysts in “click” reactions
Beilstein J. Org. Chem. 2020, 16, 551–586, doi:10.3762/bjoc.16.52
- = Cu/Au molar ratio, Gx = dendrimer generation, and AAA = dendron type). After the preparation and characterization of the CuYAu–Gx-AAA–SBA-15 catalyst, the material was employed in a triazole synthesis, and it was established that the catalyst was efficient in the Sharpless–Meldal C–N bond formation
Fluorescent phosphorus dendrimers excited by two photons: synthesis, two-photon absorption properties and biological uses
Beilstein J. Org. Chem. 2019, 15, 2287–2303, doi:10.3762/bjoc.15.221
- branches of the dendrimer structures, respectively. Also the functionalization in two compartments (core and surface, or branches and surface) was achieved. The consequences of the location of the fluorophores on the fluorescence and TPA properties have been studied. Several of these TPA fluorescent
- the mechanism of action of anticancer compounds, and for safer photodynamic therapy. Keywords: bioimaging; dendrimer; fluorescence; phosphorus; two-photon absorption; Introduction Natural luminescence phenomena such as the bioluminescence of fireflies or of certain marine microorganisms, or the
- gather several organic fluorophores (having TPA properties) in a single molecule. Dendrimers are highly branched macromolecules, which possess many properties [12] due, in particular, to a large number of terminal functions, easily modifiable. A schematized structure of a dendrimer is depicted in Figure
Design and synthesis of multivalent α-1,2-trimannose-linked bioerodible microparticles for applications in immune response studies of Leishmania major infection
Beilstein J. Org. Chem. 2019, 15, 623–632, doi:10.3762/bjoc.15.58
- hydrolyzed in the acidic phagolysosome [39][41][46]. To improve the overall synthetic sequence from our previous syntheses [11][41][42], an amino alcohol spacer was utilized to connect the trimannose reducing end to the dendrimer by means of amide bond coupling. Furthermore, the amino alcohol spacer provides
- of the commercially available rhodamine dye, TAMRA (555ex/580em), to the dendrimer would allow for standard immunofluorescence assays, to track the microparticle following cellular uptake and intracellular processing. TAMRA’s high photostability, low pH sensitivity and ease of incorporation through
- trichloroacetimidate mannosyl donors 3 and 4 [47][50] and the use of a fluorous tag containing an amino alcohol spacer rather than an alkene that would require late-stage modifications. The aminopentanol spacer 6 used at the reducing end to conjugate to the dendrimer was first protected with fluorous CbzF-NHS 5 to
Application of olefin metathesis in the synthesis of functionalized polyhedral oligomeric silsesquioxanes (POSS) and POSS-containing polymeric materials
Beilstein J. Org. Chem. 2019, 15, 310–332, doi:10.3762/bjoc.15.28
- proposed synthetic method based on the gradual development of the organic part can be used for the synthesis of new star polymers, dendrimers or hyperbranched molecules. Further examples of the use of cross metathesis of OVS with styrenes in order to form functionalizable dendrimer cores have been reported
Pathoblockers or antivirulence drugs as a new option for the treatment of bacterial infections
Beilstein J. Org. Chem. 2018, 14, 2607–2617, doi:10.3762/bjoc.14.239
- sequence of LecB differs among clinical isolates of this highly variable pathogen, with some mutations in close proximity to the carbohydrate binding site, but carbohydrate-binding function is preserved across all lectins investigated [42][43]. The glycopeptide dendrimer 13 (Figure 3) showed potent
- a full protection of mice from the toxin [59][60]. Another set of compounds called SUPER TWIG bears P blood group antigens on the antennae of a carbosilane dendrimer and was developed as an intravenously applied scavenger of circulating Shiga toxins to prevent the most severe complications in these
Tetrathiafulvalene – a redox-switchable building block to control motion in mechanically interlocked molecules
Beilstein J. Org. Chem. 2018, 14, 2163–2185, doi:10.3762/bjoc.14.190
- “defect” junctions. Only ≈25% showed a sufficient on/off ratio for a memory device. Furthermore, only a limited number of switching cycles was possible before the junctions were damaged. However, a remarkably high storage density of 1011 bits cm−1 was reached. Writing of data with the aid of dendrimer
Design, synthesis and structure of novel G-2 melamine-based dendrimers incorporating 4-(n-octyloxy)aniline as a peripheral unit
Beilstein J. Org. Chem. 2018, 14, 1704–1722, doi:10.3762/bjoc.14.145
- identified by HRMS (ESI+, ACN + TFA).
Under demanding thermal conditions, the complete amination of cyanuric chloride by D-N
NH gave the G-2 dendrimer 4 with satisfactory yield. By contrast, treatment of 1,3,5-tris(bromomethyl)benzene with D-N
NH (3 equiv, 72 h in refluxing 1,4-dioxane in the presence of
- K2CO3 as proton scavenger) resulted in no dendrimer formation; decomposition of D-N
NH was observed instead (as determined by additional NMR monitoring). Nevertheless, the desired G-2 dendrimer 5 could be obtained through an alternative route, namely, by amination of G-1 chloro-dendron D-Cl with
- building block A (Figure 1) under harsh conditions. To obtain dendrimer 6, we expected to exploit the nucleophilicity of the phenoxide groups in the N,N’,N”-tris(4-hydroxyphenyl)melamine B (Figure 1) based on the previous example of P. Gamez and co-workers [41], which involved reaction with 2-chloro[4,6-di
Nanoreactors for green catalysis
Beilstein J. Org. Chem. 2018, 14, 716–733, doi:10.3762/bjoc.14.61
- synthesis of dendrimers and their applications as nanoreactors and catalyst carriers have been extensively studied over the last decades [94][95][96]. Fan and co-workers incorporated a bis(oxazoline)-copper(II) complex in the hydrophobic core of a polyether dendrimer [11]. The copper catalytic complex was
- reactions [95][97]. The first successful attempt was reported by Chung and Rhee, in which they showed the encapsulation of a bimetallic Pt–Pd catalyst in a highly branched PMAM-OH dendrimer corona [93]. These catalytic dendrimers were employed in partial hydrogenation of 1,3-cyclooctadiene into cyclooctene
- . The utility of these dendrimers in hydrogenation reactions resulted in efficient reactions that proceeded with unprecedented selectivity of 99%. Moreover, this system is one of the first of bimetallic catalytic systems to be used for hydrogenation reactions in water. Water soluble dendrimer-stabilized
Carbohydrate inhibitors of cholera toxin
Beilstein J. Org. Chem. 2018, 14, 484–498, doi:10.3762/bjoc.14.34
- synthesising bivalent and tetravalent multivalent inhibitors and showed substantial gains in binding affinity in comparison to the corresponding monovalent ligands. Pieters and co-workers attached a lactose-derived monomeric ligand to the dendrimer 18, and found that there was an affinity and potency gain from
- divalent and tetravalent molecules [51]. Even the galactose containing dendrimers 20 bind as strongly as that of GM1 [52]. As an improved design of ligand for CT, the GM1 mimic synthesised by Bernardi and co-workers was attached to the dendrimer synthesised by the Pieters group and hence compounds 19 and
- tryptophan fluorescence quenching assay to show that octavalent lactose-based dendrimer 34 (Figure 16) had a Kd value of 33 µM as compared to monovalent lactose derivative having a Kd value of 18,000 µM [51]. Hence, compound 34 displayed 545 fold more potency per lactose unit than monovalent lactose. In
Binding abilities of polyaminocyclodextrins: polarimetric investigations and biological assays
Beilstein J. Org. Chem. 2017, 13, 2751–2763, doi:10.3762/bjoc.13.271
- internalization. However, a detailed examination of the relevant stoichiometric or thermodynamic aspects is lacking. We were interested in verifying how the presence of the dendrimer-like “bush” of polyamine pendants at the primary rim, and its protonation status as a function of the pH, might affect the
Superstructures with cyclodextrins: chemistry and applications III
Beilstein J. Org. Chem. 2016, 12, 937–938, doi:10.3762/bjoc.12.91
- the group of B. J. Ravoo using host–guest interactions between polyethyleneimine grafted with β-CD and a polyamidoamine dendrimer decorated with ferrocene. The formation of the superstructures was reversible by electrochemical oxidation of the ferrocene moieties [6]. Furthermore, significant progress
From steroids to aqueous supramolecular chemistry: an autobiographical career review
Beilstein J. Org. Chem. 2016, 12, 684–701, doi:10.3762/bjoc.12.69
- carboxylates have proven to be one of the most reliable approaches to date, it is not the only approach. For example, working with Scott Grayson across town at Tulane University we successfully formed the dendrimer–coated host shown in Figure 8 [36], as well as wide series of polymer coated derivatives coupled
Size-controlled and redox-responsive supramolecular nanoparticles
Beilstein J. Org. Chem. 2015, 11, 2388–2399, doi:10.3762/bjoc.11.260
- ) grafted with β-cyclodextrin (CD) and a positively charged ferrocene (Fc)-terminated poly(amidoamine) dendrimer, with a monovalent stabilizer at the surface. Fc was chosen for its loss of CD-binding properties when oxidizing it to the ferrocenium cation. The ionic strength was shown to play an important
- , positively charged guest dendrimer. Here, the overall concentration of the building blocks was kept constant while maintaining an equimolar stoichiometry of host and guest moieties. Moreover, our group [16] showed that SNP formation is controlled by a balance of forces between attractive supramolecular and
- PAMAM (Fc8-PAMAM) dendrimer as the multivalent guest and a monovalent stabilizer. Different stabilizers were used such as: Ad-PEG, Fc-terminated poly(ethylene glycol) (Fc-PEG), methoxypoly(ethylene glycol) (mPEG), and Ad-tetraethylene glycol (Ad-TEG). The effect of the following parameters on the
Glycodendrimers: tools to explore multivalent galectin-1 interactions
Beilstein J. Org. Chem. 2015, 11, 739–747, doi:10.3762/bjoc.11.84
- glycodendrimers provided competitive binding sites for galectin-1, which diverted galectin-1 from its typical function in cellular aggregation of DU145 cells. Keywords: dendrimer; galectin-1; glycodendrimer; multivalent; nanoparticle; Introduction Galectin-1 is a multivalent protein that mediates biological
- concentration of the dendrimer (220:1, 9:1, or 3:1 ratio of galectin-1 to dendrimer, respectively). Fluorescent microsphere standards (FluoSpheres Fluorescent Microspheres, Molecular Probes) and image analysis software (Pixcavator 6.0) were used for size quantifications. The results from the fluorescence
- 220-fold excess of galectin-1 was used. Only fourth generation dendrimer 3 forms comparable aggregates regardless of whether a slight excess of galectin-1 or a large excess of galectin-1 is added. DLS was used as a complementary technique to characterize galectin-1 nanoparticles formed using 4. These
Redox active dendronized polystyrenes equipped with peripheral triarylamines
Beilstein J. Org. Chem. 2014, 10, 3097–3103, doi:10.3762/bjoc.10.326
- polystyrene equipped with peripheral triarylamines, which exhibited two sets of reversible redox peaks in the cyclic voltammetry curves. Keywords: carbocation; cross-coupling; dendrimer; dendronized polymer; redox; Introduction Assembling small functional molecules using dendrimers [1] and dendronized
- substituents would have a uniform structure. In this paper we report on the synthesis of redox-active dendronized polystyrenes via the peripheral modification of dendronized polystyrene [28]. Results and Discussion Dendrimer 4, having a bromo functionality was prepared on a multigram scale, as shown in Figure
- and Pd[P(t-Bu)3]2 as a catalyst [30] to obtain the dendrimer 5 having peripheral diarylamino groups in a yield of 77%. Compound 5 can serve as the precursor of dendritic diarylcarbenium ions having peripheral triarylamine structures. However, its redox potential (E1/2 = 0.79 V vs SCE) is much lower
Preparation and evaluation of cyclodextrin polypseudorotaxane with PEGylated liposome as a sustained release drug carrier
Beilstein J. Org. Chem. 2014, 10, 2756–2764, doi:10.3762/bjoc.10.292
- ][22]. Also, α- and γ-CDs formed PPRXs with PEGylated proteins and provided sustained release profiles of PEGylated insulin and PEGylated lysozyme in vitro and in vivo [10][23][24][25]. Furthermore, α- and γ-CDs PPRXs with PEGylated PAMAM dendrimer and α-CD-appended PEGylated PAMAM dendrimer were
Multivalent scaffolds induce galectin-3 aggregation into nanoparticles
Beilstein J. Org. Chem. 2014, 10, 1570–1577, doi:10.3762/bjoc.10.162
- increased in size as the dendrimer generation was increased. These results show that nucleated aggregation of galectin-3 can be regulated by the nucleating polymer and provide insights that improve the general understanding of the binding and function of sugar-binding proteins. Keywords: dendrimers
- . Results and Discussion Synthesis and characterization of glycodendrimers Poly(amidoamine) (PAMAM) dendrimers are well-defined, water-soluble, symmetric scaffolds that contain a controlled and tuneable number of end groups. The number of end groups is specified by the dendrimer generation and approximately
- and the changes in Mw upon deacetylation, enabling characterization of the average number of sugars per dendrimer [30]. Additional characterization details (including 1H NMR spectra) are provided in Supporting Information File 1. Characterization of dendrimer/galectin-3 aggregates Dynamic light
Orthogonal dual thiol–chloroacetyl and thiol–ene couplings for the sequential one-pot assembly of heteroglycoclusters
Beilstein J. Org. Chem. 2014, 10, 1557–1563, doi:10.3762/bjoc.10.160
- successive attachment of sugar residues on a core scaffold such as sugar [6][7], peptide [8][9][10], dendrimer [11][12], cyclodextrin [13][14][15] and polymer [16]. The most common synthetic strategy to build such hGCs relies on a fragment-coupling approach using thiol–ene coupling [17], copper(I)-catalyzed
Synthesis and solvodynamic diameter measurements of closely related mannodendrimers for the study of multivalent carbohydrate–protein interactions
Beilstein J. Org. Chem. 2014, 10, 1524–1535, doi:10.3762/bjoc.10.157
- -mer mannosylated dendrimer 23 is shown in Scheme 5. The synthesis of 5 was accomplished starting from commercial trimesic acid chloride 1 which was readily transformed into known tripropargyl amide derivative 2 [33] using propargylamine according to Scheme 1. Amide 2 was conjugated to peracetylated 2
- give 9-mer 21 in 84% overall yield. All spectral characteristics concurred to the expected structural integrity of 21 (see Supporting Information File 1). Finally, a 27-mer mannosylated G(1)-dendrimer 23 was similarly prepared using an accelerated convergent strategy (Scheme 5). This time, the
- integrity of the final product can be readily confirmed from its characteristic spectral identification. Ultimately, dendrimer 23 was deprotected under the usual Zemplén conditions in 82% yield. Once again, all the relative integrations for each proton presented on the surface were in perfect agreement with
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