Bis(β-lactosyl)-[60]fullerene as novel class of glycolipids useful for the detection and the decontamination of biological toxins of the Ricinus communis family

• Hirofumi Dohi,
• Takeru Kanazawa,
• Akihiro Saito,
• Keita Sato,
• Hirotaka Uzawa,
• Yasuo Seto and
• Yoshihiro Nishida

Beilstein J. Org. Chem. 2014, 10, 1504–1512, doi:10.3762/bjoc.10.155

• of a red-colored colloidal suspension in aqueous medium. Its potency was obvious in the precipitation assay by using Ricinus communis proteins, which soon precipitated at the bottom while the red-colored suspension changed to colorless transparent solution. The observed phenomenon, which is based on

Biantennary oligoglycines and glyco-oligoglycines self-associating in aqueous medium

• Svetlana V. Tsygankova,
• Alexander A. Chinarev,
• Alexander B. Tuzikov,
• Nikolai Severin,
• Alexey A. Kalachev,
• Juergen P. Rabe,
• Alexandra S. Gambaryan and
• Nicolai V. Bovin

Beilstein J. Org. Chem. 2014, 10, 1372–1382, doi:10.3762/bjoc.10.140

• -called tri- and tetraantennary molecules, were found to form highly ordered supramers in aqueous medium. The formation of these supramers occurred either spontaneously or due to the assistance of a mica surface. The driving force of the supramer formation is hydrogen bonding, the polypeptide chain

• described tetraantennary [2] and triantennary [3] oligoglycines capable of spontaneous or surface-promoted formation of flat layers in aqueous medium. These layers are one or two molecules thick. The stability was attributed to the formation of a network of hydrogen bonds. This class of supramers has been

• amino group the solution becomes neutral (рН 6.5), in the case of two Nа2CO3 equivalents the pH value is more than 8.5 (basic solution, denoted as pH > 8.5). At n < 4 peptides with an oligoethylene glycol core and the cores С2 and С10 did not form associates in aqueous medium in all the studied ranges

Staudinger ligation towards cyclodextrin dimers in aqueous/organic media. Synthesis, conformations and guest-encapsulation ability

• Malamatenia D. Manouilidou,
• Yannis G. Lazarou,
• Irene M. Mavridis and
• Konstantina Yannakopoulou

Beilstein J. Org. Chem. 2014, 10, 774–783, doi:10.3762/bjoc.10.73

• toward CD dimer preparation. In addition to linker 2 (Scheme 2a), the new double arylphosphine methyl ester linker 3 has been developed (Scheme 2b) that enabled facile homodimer formation in a single step, in organic/aqueous medium. As an indispensable part of this approach, the full NMR spectroscopic

Silver and gold-catalyzed multicomponent reactions

• Giorgio Abbiati and
• Elisabetta Rossi

Beilstein J. Org. Chem. 2014, 10, 481–513, doi:10.3762/bjoc.10.46

• for Au NP, and these heterogeneous systems were tested as recyclable catalysts in an A3-coupling. The former was effective in three simple model reactions as a bifunctional catalyst (Au/acid) in aqueous medium at 70 °C. The latter works well in chloroform at 60 °C and tolerates a number of substituted

Advancements in the mechanistic understanding of the copper-catalyzed azide–alkyne cycloaddition

• Regina Berg and
• Bernd F. Straub

Beilstein J. Org. Chem. 2013, 9, 2715–2750, doi:10.3762/bjoc.9.308

• ligand (1.1 mol %) the test reaction of benzyl azide with phenylacetylene gave 99% yield after one hour in an aqueous medium (DMSO:H2O 1:3) [85]. CuAAC catalysis with molecularly defined copper(I) complexes as (pre-)catalysts Only recently, the potential of copper(I) acetate as heterogeneous catalyst for

Structure elucidation of β-cyclodextrin–xylazine complex by a combination of quantitative ¹H–¹H ROESY and molecular dynamics studies

• Syed Mashhood Ali,
• Kehkeshan Fatma and
• Snehal Dhokale

Beilstein J. Org. Chem. 2013, 9, 1917–1924, doi:10.3762/bjoc.9.226

• Syed Mashhood Ali Kehkeshan Fatma Snehal Dhokale Department of Chemistry, Aligarh Muslim University, Aligarh-202002, India National Chemical Laboratory, Pune-411008, India 10.3762/bjoc.9.226 Abstract The complexation of xylazine with β-cyclodextrin was studied in aqueous medium. 1H NMR titrations

• here the study of the complexation of β-CD with xylazine (XZ) (Figure 1) in aqueous medium by NMR spectroscopy and molecular dynamics. Xylazine has two rings, one substituted benzene ring which can only partially penetrate the CD cavity due to the presence of two methyl groups and a heterocyclic ring

• which should prefer aqueous medium outside the cavity. The study suggests that highly reliable structural information can be deduced by a combination of a poorly resolved 1H–1H ROESY spectrum, which otherwise gives only the information about the part of the guest included, and careful interpretation of

Topochemical control of the photodimerization of aromatic compounds by γ-cyclodextrin thioethers in aqueous solution

• Hai Ming Wang and
• Gerhard Wenz

Beilstein J. Org. Chem. 2013, 9, 1858–1866, doi:10.3762/bjoc.9.217

• Pd nanocage [33] in aqueous solution, both giving rise to the exclusive formation of the syn isomer. Unfortunately, the quantum yields have not been reported for these systems so far. ACE also formed inclusion compounds with β-CD thioethers 1–7, which are soluble in aqueous medium. The highest

• photodimerized approximately 10 times faster in aqueous medium than the same uncomplexed guests in aqueous solution. Since these photo dimerizations of hydrophobic guests are performable at neutral pH in optically clear solution in water they are suitable for preparative applications. Isolation of the

Polymeric redox-responsive delivery systems bearing ammonium salts cross-linked via disulfides

• Christian Dollendorf,
• Martin Hetzer and
• Helmut Ritter

Beilstein J. Org. Chem. 2013, 9, 1652–1662, doi:10.3762/bjoc.9.189

• to Table 4). This trend is similar to the increasing swelling degrees with increasing amounts of CL 1. The thiol side-chains increase the hydrophilicity by forming hydrogen bonds with the surrounding aqueous medium. Thus, more energy is needed to disrupt these interactions, leading to higher

Molecular assembly of amino acid interlinked, topologically symmetric, π-complementary donor–acceptor–donor triads

• M. B. Avinash,
• K. V. Sandeepa and
• T. Govindaraju

Beilstein J. Org. Chem. 2013, 9, 1565–1571, doi:10.3762/bjoc.9.178

• exhibited only an incremental red shift of absorption maxima similar to that observed in the case of 3, in aqueous DMSO (see Supporting Information File 1). In addition, the fluorescence emission for 1, 2 and 3 was found to be quenched in DMSO and NMP as well as in their aqueous medium (Figure 2b

Chemical modification allows phallotoxins and amatoxins to be used as tools in cell biology

• Jan Anderl,
• Hartmut Echner and
• Heinz Faulstich

Beilstein J. Org. Chem. 2012, 8, 2072–2084, doi:10.3762/bjoc.8.233

• represent a lipophilic phase in an aqueous medium, and amphiphilic compounds brought into this system will distribute between the two phases according to their nature. This process is similar to the distribution the substance will take between n-octanol and water, an idea that has been suggested by Palm et

The Amadori rearrangement as glycoconjugation method: Synthesis of non-natural C-glycosyl type glycoconjugates

• Katharina Gallas,
• Gerit Pototschnig,
• Florian Adanitsch,
• Arnold E. Stütz and
• Tanja M. Wrodnigg

Beilstein J. Org. Chem. 2012, 8, 1619–1629, doi:10.3762/bjoc.8.185

• chemistry (Huisgen cycloaddition) [4][5], glycosylation protocols [6][7], and Staudinger ligation [8], just to mention the most prominent examples. However, many applications in this respect require a ligation method that is functional in aqueous medium, and, for economic purposes in general, protecting

Impact of cyclodextrins on the behavior of amphiphilic ligands in aqueous organometallic catalysis

• Hervé Bricout,
• Estelle Léonard,
• Christophe Len,
• David Landy,
• Frédéric Hapiot and
• Eric Monflier

Beilstein J. Org. Chem. 2012, 8, 1479–1484, doi:10.3762/bjoc.8.167

• that the addition of randomly modified β-cyclodextrin (RAME-β-CD) in aqueous medium could have a beneficial impact on the catalytic performances of phosphane-based aggregates in the Pd-catalyzed cleavage of allyl carbonates (Tsuji–Trost reaction). The RAME-β-CD/phosphane supramolecular interactions

• complexes were present in the aqueous medium and significantly contribute to the beneficial effect observed for stoichiometric RAME-β-CD/phosphane mixtures. Accordingly, in this study we showed that RAME-β-CD could positively interact with phosphane-containing aggregates in a very narrow concentration range

An easily accessible sulfated saccharide mimetic inhibits in vitro human tumor cell adhesion and angiogenesis of vascular endothelial cells

• Grazia Marano,
• Claas Gronewold,
• Martin Frank,
• Anette Merling,
• Christian Kliem,
• Sandra Sauer,
• Manfred Wiessler,
• Eva Frei and
• Reinhard Schwartz-Albiez

Beilstein J. Org. Chem. 2012, 8, 787–803, doi:10.3762/bjoc.8.89

• ) was obtained in a yield of 85%. It was found to be important that after the debenzoylation the aqueous medium be neutralized with 0.1 M HCl under control of a pH-meter, to pH 7.2. Under the highly acidic conditions induced by a Dowex H+ ion-exchange resin, the free sulfate decomposes. The product was

Catalyst-free and solvent-free Michael addition of 1,3-dicarbonyl compounds to nitroalkenes by a grinding method

• Zong-Bo Xie,
• Na Wang,
• Ming-Yu Wu,
• Ting He,
• Zhang-Gao Le and
• Xiao-Qi Yu

Beilstein J. Org. Chem. 2012, 8, 534–538, doi:10.3762/bjoc.8.61

• [22], a transition-metal-free process for the synthesis of substituted dihydrofurans [23] and a catalyst-free tandem reaction for the synthesis of 5-hydroxy-1,5-dihydro-2H-pyrrol-2-ones in aqueous medium [24]. Recently, when carrying out the reaction of β-nitrostyrene with 1,3-cyclopentanedione under

Highly efficient cyclosarin degradation mediated by a β-cyclodextrin derivative containing an oxime-derived substituent

• Michael Zengerle,
• Florian Brandhuber,
• Christian Schneider,
• Franz Worek,
• Georg Reiter and
• Stefan Kubik

Beilstein J. Org. Chem. 2011, 7, 1543–1554, doi:10.3762/bjoc.7.182

• the phosphonylation of this nucleophilic group, similar to the phosphonylation of the serine residue in the active site of AChE during OP-mediated inhibition of this enzyme. If the compound thus formed is hydrolytically unstable, it will be cleaved in the aqueous medium, releasing the original

Reductive amination with zinc powder in aqueous media

• Giovanni B. Giovenzana,
• Daniela Imperio,
• Andrea Penoni and
• Giovanni Palmisano

Beilstein J. Org. Chem. 2011, 7, 1095–1099, doi:10.3762/bjoc.7.125

• promoting its use as a green reductant: i) atom economy, ii) low toxicity, iii) relative stability in air and water, and iv) low cost. Examples of the reduction of imines by zinc metal are reported, either in organic solvents [25][26][27][28][29] or in basic aqueous medium [30]. We recognized that this

• at room temperature. The reaction was complete within 24 h and standard work up afforded the desired secondary amine 1a in 69–72% yield along with hydrodimers 2a as byproducts (0–8%) (Scheme 1). The use of an alkaline aqueous medium was necessary in order to fulfill the requirements of the reduction

Nano copper oxide catalyzed synthesis of symmetrical diaryl sulfides under ligand free conditions

• K. Harsha Vardhan Reddy,
• V. Prakash Reddy,
• A. Ashwan Kumar,
• G. Kranthi and
• Y.V.D. Nageswar

Beilstein J. Org. Chem. 2011, 7, 886–891, doi:10.3762/bjoc.7.101

• aqueous medium at 130 °C for 48 h. Tao et al. described the synthesis of diaryl sulfides catalyzed by CuI via cross-coupling between aryl halides and thioacetamide using Cs2CO3 as the base and DMSO–H2O as the solvent at 120 °C [44]. These recently developed protocols involve expensive catalytic systems

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

pH-Responsive chromogenic-sensing molecule based on bis(indolyl)methene for the highly selective recognition of aspartate and glutamate

• Litao Wang,
• Xiaoming He,
• Yong Guo,
• Jian Xu and
• Shijun Shao

Beilstein J. Org. Chem. 2011, 7, 218–221, doi:10.3762/bjoc.7.29

• hand, compared with a strong base NaOH, the basicity of the basic amino acids (such as Arg or Lys) is not strong enough to induce deprotonation of 1. These results show the high selectivity and sensitivity of 1 towards the acidic amino acids in aqueous medium. The ratio of acetonitrile to water does

New amphiphilic glycopolymers by click functionalization of random copolymers – application to the colloidal stabilisation of polymer nanoparticles and their interaction with concanavalin A lectin

• Otman Otman,
• Paul Boullanger,
• Eric Drockenmuller and
• Thierry Hamaide

Beilstein J. Org. Chem. 2010, 6, No. 58, doi:10.3762/bjoc.6.58

• surfactants, are required to assure the colloidal stabilization of the polymer nanoparticles in aqueous medium. The properties of micelles (cmc, size and dynamics) depend on the chemical structures of amphiphilic copolymers. Macromolecular non-ionic surfactants appear to be the best suited from both the

Molecular recognition of organic ammonium ions in solution using synthetic receptors

• Andreas Späth and
• Burkhard König

Beilstein J. Org. Chem. 2010, 6, No. 32, doi:10.3762/bjoc.6.32

• coulombic interactions are around 8 kJ/mol [15]. In aqueous medium ion pair formation is primarily driven by entropy, not directly by coulombic forces [16]. The binding energy is, in general, independent of the geometry, polarizability of the ions or the formation of a salt bridge. In addition, the

Synthesis of bis(3-{[2-(allyloxy)ethoxy]methyl}-2,4,6-trimethylbenzoyl)(phenyl)phosphine oxide – a tailor-made photoinitiator for dental adhesives

• Norbert Moszner,
• Iris Lamparth,
• Jörg Angermann,
• Urs Karl Fischer,
• Frank Zeuner,
• Thorsten Bock,
• Robert Liska and
• Volker Rheinberger

Beilstein J. Org. Chem. 2010, 6, No. 26, doi:10.3762/bjoc.6.26

• significantly impair the formation of initiating radicals. Moreover, especially in the aqueous medium, the polar radical ions are well solvated by the surrounding medium, thus inhibiting the proton transfer. If proton transfer occurs, both non-ionic and therefore rather hydrophobic species are kept in the

Mitomycins syntheses: a recent update

• Jean-Christophe Andrez

Beilstein J. Org. Chem. 2009, 5, No. 33, doi:10.3762/bjoc.5.33

• semiquinone in aqueous anaerobic medium is also very fast [49] whereas under aqueous aerobic conditions, the semiquinone reoxidizes to the quinone more quickly than it disproportionates [50]. Thus, the conclusion was made that in aqueous medium the same hydroquinone intermediate was responsible for the

Synthesis and enzymatic evaluation of 2- and 4-aminothiazole- based inhibitors of neuronal nitric oxide synthase

• Graham R. Lawton,
• Haitao Ji,
• Pavel Martásek,
• Linda J. Roman and
• Richard B. Silverman

Beilstein J. Org. Chem. 2009, 5, No. 28, doi:10.3762/bjoc.5.28

• . Nonetheless, the synthetic methodology is useful for the construction of this ring system. 4-Aminothiazole-based inhibitors with various alkyl groups at the thiazole 5-position could be synthesized, but proved to be unstable in aqueous medium. This is a valuable insight for others contemplating this ring

Phase- vanishing halolactonization of neat substrates

• Nicole Windmon and
• Veljko Dragojlovic

Beilstein J. Org. Chem. 2008, 4, No. 29, doi:10.3762/bjoc.4.29

• from addition of bromine to a double bond, were by-products. The reaction mechanism of halolactonization in basic aqueous medium is believed to involve formation of a halonium ion followed by attack of an oxygen nucleophile [13]. Reaction times ranged from 20–60 minutes when Br2 or ICl were used to