Glycosystems in nanotechnology: Gold glyconanoparticles as carrier for anti-HIV prodrugs

• Fabrizio Chiodo,
• Marco Marradi,
• Javier Calvo,
• Eloisa Yuste and
• Soledad Penadés

Beilstein J. Org. Chem. 2014, 10, 1339–1346, doi:10.3762/bjoc.10.136

• related to HIV envelope [18]. GNPs coated with oligomannosides of the gp120 (manno-GNPs) were able to inhibit the DC-SIGN-mediated HIV-1 trans-infection of human T-cells [19] and gold glyconanoparticles coated with sulfated ligands showed to interfere with the adhesion/fusion of HIV during its entry [20

Automated solid-phase peptide synthesis to obtain therapeutic peptides

• Veronika Mäde,
• Sylvia Els-Heindl and
• Annette G. Beck-Sickinger

Beilstein J. Org. Chem. 2014, 10, 1197–1212, doi:10.3762/bjoc.10.118

• Bivalirudin have been manufactured in multikilogram scale [10][19]. Enfuvirtide (T-20/ Fuzeon®), for example, is an efficient membrane fusion inhibitor for HIV treatment consisting of 36 amino acids [80]. The large-scale bulk production of Fuzeon® is performed by solution-phase fragment condensation from

• interaction, there is also the possibility to increase peptide stability by direct fusion with HSA. One example of this effect is the GLP-1 analog CJC-1131. It contains a covalently attached albumin moiety and a D-amino acid at a labile position to obtain increased metabolic stability [107]. PEGylation of

Triol-promoted activation of C–F bonds: Amination of benzylic fluorides under highly concentrated conditions mediated by 1,1,1-tris(hydroxymethyl)propane

• Pier Alexandre Champagne,
• Alexandre Saint-Martin,
• Mélina Drouin and
• Jean-François Paquin

Beilstein J. Org. Chem. 2013, 9, 2451–2456, doi:10.3762/bjoc.9.283

• all could be observed without the activating agent. It is important to mention for this entry that even if morpholine is the only liquid component at room temperature, a homogeneous solution is generated around 60 °C by the fusion of 1,1,1-tris(hydroxymethyl)propane (melting point 56–58 °C). Starting

Gold(I)-catalyzed enantioselective cycloaddition reactions

• Fernando López and
• José L. Mascareñas

Beilstein J. Org. Chem. 2013, 9, 2250–2264, doi:10.3762/bjoc.9.264

• complex, encompasses internally monosubstituted allenes, as well as disubstituted counterparts, offering a direct entry to 5,7 bicyclic systems including those with all-carbon quaternary stereocenters at the ring fusion. In contrast to the intramolecular counterpart, gold-catalyzed intermolecular

Hypervalent iodine/TEMPO-mediated oxidation in flow systems: a fast and efficient protocol for alcohol oxidation

• Nida Ambreen,
• Ravi Kumar and
• Thomas Wirth

Beilstein J. Org. Chem. 2013, 9, 1437–1442, doi:10.3762/bjoc.9.162

• . Both syringes were placed in a syringe pump (Fusion 100) and connected via a T-piece to a tubing reactor (PTFE, length: 4 m, internal diameter: 0.75 mm). The tubing reactor was immersed in a thermocontrolled water bath at 35 °C. The total flow rate was adjusted to 0.4 mL min–1 resulting in a residence

Amyloid-β probes: Review of structure–activity and brain-kinetics relationships

• Todd J. Eckroat,
• Abdelrahman S. Mayhoub and
• Sylvie Garneau-Tsodikova

Beilstein J. Org. Chem. 2013, 9, 1012–1044, doi:10.3762/bjoc.9.116

• date has been [125I]IMPY ([125I]140e). Representative of this scaffold, the synthesis of [125I]140e used a fusion reaction between 2-amino-5-iodopyridine (143) and an α-bromoacetophenone 144 to form 140e, which was then radiolabeled (Scheme 10B) [90]. This preparation has since been improved by Kung et

Preparation and ring-opening reactions of N-diphenylphosphinyl vinyl aziridines

• Ashley N. Jarvis,
• Andrew B. McLaren,
• Helen M. I. Osborn and
• Joseph Sweeney

Beilstein J. Org. Chem. 2013, 9, 852–859, doi:10.3762/bjoc.9.98

• . Optimization studies We next sought to improve the yields of the vinyl aziridination and thus modified our experimental rubric by carrying out the fusion of ZnCl2 under vacuum, rather than at atmospheric pressure. Using this minor modification, the reaction of N-diphenylphosphinylbenzaldimine furnished vinyl

1-n-Butyl-3-methylimidazolium-2-carboxylate: a versatile precatalyst for the ring-opening polymerization of ε-caprolactone and rac-lactide under solvent-free conditions

• Astrid Hoppe,
• Faten Sadaka,
• Claire-Hélène Brachais,
• Gilles Boni,
• Jean-Pierre Couvercelle and
• Laurent Plasseraud

Beilstein J. Org. Chem. 2013, 9, 647–654, doi:10.3762/bjoc.9.73

• according to Equation 3 with ΔHc being the crystallization enthalpy, and ΔH' the enthalpy of fusion of PCL, ΔH' = 161.1 J·g−1) affects directly the melting temperature (Tm). Thus, a decrease of molecular weight causes a decrease of the Tm. Analysis of the crystallinity of the various polycaprolactones by

Synthesis of 2,3-dihydronaphtho[2,3-d][1,3]thiazole-4,9-diones and 2,3-dihydroanthra[2,3-d][1,3]thiazole-4,11-diones and novel ring contraction and fusion reaction of 3H-spiro[1,3-thiazole-2,1'-cyclohexanes] into 2,3,4,5-tetrahydro-1H-carbazole-6,11-diones

• Lidia S. Konstantinova,
• Kirill A. Lysov,
• Ljudmila I. Souvorova and
• Oleg A. Rakitin

Beilstein J. Org. Chem. 2013, 9, 577–584, doi:10.3762/bjoc.9.62

• ., ring contraction and fusion products. A plausible mechanism was proposed for the formation of the products. Keywords: anthracene-1,4-diones; 1H-carbazole-6,11-diones; fused thiazoles; fusion reaction; heterocycles; naphthoquinones; ring contraction; sulfur–nitrogen; Introduction The 1,4

• -ethyldiisopropylamine in the reaction of 2-(methylamino)anthracene-1,4-diones with sulfur monochloride was discovered and explained. 3H-Spiro(thiazol-2,1'-cyclohexanes) underwent a new ring contraction and fusion reaction resulting in the formation of tetrahydroindoles. Experimental Melting points were determined on a

Hydrophobic analogues of rhodamine B and rhodamine 101: potent fluorescent probes of mitochondria in living C. elegans

• Laurie F. Mottram,
• Safiyyah Forbes,
• Brian D. Ackley and
• Blake R. Peterson

Beilstein J. Org. Chem. 2012, 8, 2156–2165, doi:10.3762/bjoc.8.243

• Mitochondria undergo dynamic fusion and fission events that affect the structure and function of these critical energy-producing cellular organelles. Defects in these dynamic processes have been implicated in a wide range of human diseases including ischemia, neurodegeneration, metabolic disease, and cancer

• mitochondrial stains rhodamine 123, rhodamine 6G, and rhodamine B, as well as the structurally related fluorophores rhodamine 101, and basic violet 11, revealed that HRB and HR101 are the most potent mitochondrial probes, enabling imaging of mitochondrial motility, fusion, and fission in the germline and other

• ; fluorescence; fusion; imaging; in vivo; microscopy; mitochondria; model organisms; organelle; rhodamine; spectroscopy; Introduction Fluorescent molecular probes represent critical tools for studies of chemical biology [1]. These compounds allow the creation of sensitive enzyme substrates, sensors of a wide

Regioselective synthesis of 7,8-dihydroimidazo[5,1-c][1,2,4]triazine-3,6(2H,4H)-dione derivatives: A new drug-like heterocyclic scaffold

• Nikolay T. Tzvetkov,
• Harald Euler and
• Christa E. Müller

Beilstein J. Org. Chem. 2012, 8, 1584–1593, doi:10.3762/bjoc.8.181

• ring fusion of C4a–N8 (1, 3 and 4) or C8a–N5 atoms (2), and differ in the arrangement of the substitution pattern of the imidazotriazine framework (Figure 1). The structural variation of imidazo[1,2,4]triazine derivatives poses a significant challenge, particularly if a broad variety of substituents is

• time. We observed that the adding of molecular sieves (4 Å) to the reaction medium greatly improved the yields of condensed products 23–25. The regioselective two-step cyclization of 14 yielding imidazo[5,1-c][1,2,4]triazine-3,6-dione (24, pathway A) via an N5–C5 ring fusion is outlined in Scheme 4

• (HSQC and HMBC) in combination with 1H and 13C NMR, and additionally by LC/ESI-MS (m/z 287 [M + H]+/285 [M − H]− for 24, 355 [M + H]+/353 [M − H]− for 25). Molecular modelling was performed to calculate the respective geometries by using the MMFF95 force field [27] assuming an N1–C5 ring fusion during

Mannose-decorated cyclodextrin vesicles: The interplay of multivalency and surface density in lectin–carbohydrate recognition

• Ulrike Kauscher and
• Bart Jan Ravoo

Beilstein J. Org. Chem. 2012, 8, 1543–1551, doi:10.3762/bjoc.8.175

• guest interaction with the surface of the vesicles has become a useful system to investigate recognition, adhesion and fusion of biological cell membranes [24][25][26]. In this context, amphiphilic cyclodextrins are a promising platform due to their ability to form stable bilayer vesicles that can be

Stereoselective synthesis of trans-fused iridoid lactones and their identification in the parasitoid wasp Alloxysta victrix, Part II: Iridomyrmecins

• Robert Hilgraf,
• Nicole Zimmermann,
• Lutz Lehmann,
• Armin Tröger and
• Wittko Francke

Beilstein J. Org. Chem. 2012, 8, 1256–1264, doi:10.3762/bjoc.8.141

• iridoid lactones which are present in the cephalic secretions of Alloxysta victrix show an unusual trans-fusion. Among the compounds showing this structure, only the lactone X [1] (Figure 1) and a compound with the same relative configuration [21] have been described from insects so far. In contrast to

Investigation of the network of preferred interactions in an artificial coiled-coil association using the peptide array technique

• Raheleh Rezaei Araghi,
• Carsten C. Mahrenholz,
• Rudolf Volkmer and
• Beate Koksch

Beilstein J. Org. Chem. 2012, 8, 640–649, doi:10.3762/bjoc.8.71

• selectivity, forming stable multimers with strong interhelical interactions. Recently, their potential as drug targets has become the focus of medical research [3]. Their effectiveness in the successful inhibition of membrane fusion proteins of viruses, such as HIV [4] and avian influenza [5], also supports

Synthesis of fluorinated maltose derivatives for monitoring protein interaction by ¹⁹F NMR

• Michaela Braitsch,
• Hanspeter Kählig,
• Georg Kontaxis,
• Michael Fischer,
• Toshinari Kawada,
• Robert Konrat and
• Walther Schmid

Beilstein J. Org. Chem. 2012, 8, 448–455, doi:10.3762/bjoc.8.51

• rationale for choosing maltose lies in the fact that maltodextrin/maltose-binding protein (MBP) is a generally applicable protein fusion tag with beneficial solution properties and therefore widely used in molecular biology [12][13]. MBP belongs to the family of periplasmic binding proteins, which are

• -labeled maltose (gluco- and manno-type) to the maltose-binding protein and a MBP-V53 fusion protein comprising five V3 modules of the LDL receptor in a linear tandem arrangement (V33333) were analyzed. As can be seen in Figure 3 and Figure 4, the stereoisomers of 2-F labeled maltose clearly exhibit

• , probably corresponding to the closed- and open-domain conformations of MBP; but only the α-anomer complex has been observed in X-ray structures of MBP with maltose [21]. Furthermore we used this technique for probing the interactions between 2-F-maltose and the MBP-V53 [43][44] fusion protein, which has

Coupled chemo(enzymatic) reactions in continuous flow

• Ruslan Yuryev,
• Simon Strompen and
• Andreas Liese

Beilstein J. Org. Chem. 2011, 7, 1449–1467, doi:10.3762/bjoc.7.169

• . This principle has been recently utilized in applied biocatalysis for the development of novel types of catalysts for multistep reaction cascades, i.e., metabolon catalysts [55], self-assembled fusion protein complexes [56] and polymerosomes [57]. It is very probable that application of these novel

Intramolecular hydroamination of alkynic sulfonamides catalyzed by a gold–triethynylphosphine complex: Construction of azepine frameworks by 7-exo-dig cyclization

• Hideto Ito,
• Tomoya Harada,
• Hirohisa Ohmiya and
• Masaya Sawamura

Beilstein J. Org. Chem. 2011, 7, 951–959, doi:10.3762/bjoc.7.106

• have geminal disubstitution or ring fusion within a linker chain connecting the attacking nitrogen atom and the alkyne moiety. It should be noted, however, that 7-“endo”-dig cyclizations of (o-alkynyl)phenylacetamides and a diynamide were achieved with gold and palladium complexes [39][46][52][53], and

An overview of the key routes to the best selling 5-membered ring heterocyclic pharmaceuticals

• Marcus Baumann,
• Ian R. Baxendale,
• Steven V. Ley and
• Nikzad Nikbin

Beilstein J. Org. Chem. 2011, 7, 442–495, doi:10.3762/bjoc.7.57

• as T-cells and macrophages followed by viral fusion and entry into white blood cells. Maraviroc blocks this pathway by acting as an antagonist for the CCR-5 receptor hence disrupting HIV life cycle. The structural features of this molecule are a geminal difluorocyclohexyl carboxamide which is linked

Review of “Stereochemistry Workbook, 191 Problems and Solutions” by K.-H. Hellwich and C. D. Siebert

• Roald Hoffmann

Beilstein J. Org. Chem. 2009, 5, No. 38, doi:10.3762/bjoc.5.38

• variety the normal world generates suffices. But it is good to be aware of just what the assumptions are. Let me give an example. In one problem, a set of isomers of a bicyclic compound (cyclothiazide) is eliminated from discussion because a bridge can be formed only by cis fusion. In another example, two

Radical cascades using enantioenriched 7-azabenzonorbornenes and their applications in synthesis

• David M. Hodgson and
• Leonard H. Winning

Beilstein J. Org. Chem. 2008, 4, No. 38, doi:10.3762/bjoc.4.38

• for the rapid enhancement of molecular complexity. Furthermore, in the structurally similar system created by the formal fusion of the norbornenyl skeleton with an aromatic ring, the ‘nortricyclyl’ radical is delocalised in the originally aromatic π-system. Ring-opening of this ‘nortricyclyl’ radical

Total synthesis of the indolizidine alkaloid tashiromine

• Stephen P. Marsden and
• Alison D. McElhinney

Beilstein J. Org. Chem. 2008, 4, No. 8, doi:10.1186/1860-5397-4-8

• trifluoroacetic acid in dichloromethane at room temperature gave the bicyclic amide 2 in 85% yield as a 96:4 mixture of diastereomers. The identity of the major diastereomer was confirmed by comparison of the spectral data with those of Hiemstra [16]: specifically, the signal for the (ring-fusion) proton at C6