Synthesis of uniform cyclodextrin thioethers to transport hydrophobic drugs

• Lisa F. Becker,
• Dennis H. Schwarz and
• Gerhard Wenz

Beilstein J. Org. Chem. 2014, 10, 2920–2927, doi:10.3762/bjoc.10.310

• amphiphiles, such as methyl cellulose [47], poly(N-isopropylacrylamide) (pNiPAAm) [48], and also for methylated CDs [49], and CDs completely modified with oligoethylene glycol units [50]. While the LCST transition of the statistical derivative 2b1 was within a rather broad temperature range (30–40 °C), the

Encapsulation of biocides by cyclodextrins: toward synergistic effects against pathogens

• Véronique Nardello-Rataj and
• Loïc Leclercq

Beilstein J. Org. Chem. 2014, 10, 2603–2622, doi:10.3762/bjoc.10.273

• biocide is generally not used alone. Typically, the formulations also contain polyethoxylated fatty alcohols leading thus to disinfectant/detergent compositions. In such surfactant mixtures, the presence of the various amphiphiles results in a spontaneous co-aggregation obtained at lower concentrations

The search for new amphiphiles: synthesis of a modular, high-throughput library

• George C. Feast,
• Thomas Lepitre,
• Xavier Mulet,
• Charlotte E. Conn,
• Oliver E. Hutt,
• G. Paul Savage and
• Calum J. Drummond

Beilstein J. Org. Chem. 2014, 10, 1578–1588, doi:10.3762/bjoc.10.163

• anomeric linkages. A library of 80 amphiphiles was subsequently produced, using a 24-vial array, with the majority formed in very good to excellent yields. A preliminary assessment of the liquid-crystalline phase behaviour is also presented. Keywords: amphiphiles; carbohydrates; click chemistry; high

• throughput; library synthesis; Introduction Amphiphilic compounds contain a hydrophilic polar head group and a hydrophobic non-polar side chain. Upon addition of water, these amphiphiles may self-assemble into lyotropic phases that have a variety of uses, from simple household detergents and cleaning

• ]. Increasing the lattice parameter of the liquid-crystalline phase may also facilitate the uptake of larger bioactive molecules [4]. At present, only a small selection of amphiphiles is used in the aforementioned applications. Research into the design, synthesis, and material characterisation of new

Atherton–Todd reaction: mechanism, scope and applications

• Stéphanie S. Le Corre,
• Mathieu Berchel,
• Hélène Couthon-Gourvès,
• Jean-Pierre Haelters and
• Paul-Alain Jaffrès

Beilstein J. Org. Chem. 2014, 10, 1166–1196, doi:10.3762/bjoc.10.117

• for biological applications. The selected examples to illustrate the applications of the Atherton–Todd reaction mainly cover the past 15 years. Keywords: amphiphiles; flame retardant; lipid conjugates; organophosphorus; phosphoramidate; phosphate; Review 1. Introduction The reaction of

Influence of cyclodextrin on the solubility and the polymerization of (meth)acrylated Triton^® X-100

• Melanie Kemnitz and
• Helmut Ritter

Beilstein J. Org. Chem. 2012, 8, 2176–2183, doi:10.3762/bjoc.8.245

• the poly(ethylene glycol) substituent is hydrophilic. Because of this amphiphilic character, Triton® X-100 can be described as a short AB block co-oligomer [1]. Long amphiphiles are relatively flexible and provide a lower critical micelle concentration (CMC) [2]. The CMC of Triton® X-100 is 0.22 mM [3

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

• functionalized by self-assembly [27]. To this end, cyclodextrins are modified with long alkyl chains (“tails”) and short oligo(ethylene glycol) head groups. These macrocyclic amphiphiles form unilamellar bilayer vesicles in aqueous solution upon hydration of a thin film cast by evaporation from organic solution

Progress in liquid crystal chemistry II

• Sabine Laschat

Beilstein J. Org. Chem. 2012, 8, 118–119, doi:10.3762/bjoc.8.13

• mesogens, amphiphiles, and liquid-crystalline nanoparticles. It is our goal to give the reader insight into both synthetic aspects of liquid crystal chemistry as well as application-oriented properties, such as photoconductivity or chirality transfer, to name just a few selected examples. Finally, we would

Amphiphilic dendritic peptides: Synthesis and behavior as an organogelator and liquid crystal

• Baoxiang Gao,
• Hongxia Li,
• Defang Xia,
• Sufang Sun and
• Xinwu Ba

Beilstein J. Org. Chem. 2011, 7, 198–203, doi:10.3762/bjoc.7.26

• display a wide range of physical properties often exceeding those of synthetic polymers [4][5]. Peptide-amphiphiles (PAs) represent an attractive class of bioactive molecules as they self-assemble into a variety of nanostructures, many of which have promising biological activity due to the exposed peptide

Differences between β-Ala and Gly-Gly in the design of amino acids-based hydrogels

• Andreea Pasc,
• Firmin Obounou Akong,
• Sedat Cosgun and
• Christine Gérardin

Beilstein J. Org. Chem. 2010, 6, 973–977, doi:10.3762/bjoc.6.109

• vs Gly-Gly-based hydrogelators. Previously, in our group, amino acid based amphiphiles i.e. Gly-Gly-His-EO2-Alk, a trimodular amphiphile (containing three domains: H-bond donor and acceptor/hydrophilic/hydrophobic domain, respectively) were reported to act as hydrogelators and that the gelation

• acid-based amphiphiles have been received much attention in the recent past on account of their biocompatibility and eco-friendly nature. Biologically inspired His-based surfactants are of particular interest not only for their antioxidant properties and their potential therapeutic effects, but also as

• amphiphiles, we have recently shown that Gly-Gly-His and β-Ala-His-amphiphiles act as efficient hydrogelators [10]. The histidine moiety seems to play a key role in hydrogel formation, developing not only π-π stacking interactions but also by H-bonding; by replacing histidine by phenylalanine no hydrogel

Oxalyl retro-peptide gelators. Synthesis, gelation properties and stereochemical effects

• Janja Makarević,
• Milan Jokić,
• Leo Frkanec,
• Vesna Čaplar,
• Nataša Šijaković Vujičić and
• Mladen Žinić

Beilstein J. Org. Chem. 2010, 6, 945–959, doi:10.3762/bjoc.6.106

• assemblies due to their structural resemblance to bola-amphiphiles. In the FTIR spectra of (S,S)-1b and (S,R)-1b toluene gels one wide band or two poorly resolved NH bands, respectively, appear in the region of 3260–3320 cm−1 corresponding to a hydrogen bonded NH. In addition, the ester carbonyl and amide I

• )oxalamides and that both show a strong resemblance to bola-amphiphiles which are known to organize into bilayers [71]. The temperature dependence of CD spectra of decalin gels formed by diastereoisomeric methyl esters (S,R)-1b and (S,S)-1b (Figure 8a, b, respectively) was also investigated. At room

Pyridinium based amphiphilic hydrogelators as potential antibacterial agents

• Sayanti Brahmachari,
• Sisir Debnath,
• Sounak Dutta and
• Prasanta Kumar Das

Beilstein J. Org. Chem. 2010, 6, 859–868, doi:10.3762/bjoc.6.101

• rapid expansion of this field. In the present work we report the facile synthesis of amphiphilic hydrogelators having a quaternary pyridinium unit coupled to a hydrophobic long alkyl chain through an amide bond. Different amphiphiles with various hydrophobic chain length and polar head groups were

• originates from the interdigitated bilayer packing of the amphiphile leading to the development of an efficient hydrogel. Interestingly, the presence of the pyridinium scaffold along with the long alkyl chain render these amphiphiles inherently antibacterial. The amphiphilic hydrogelators exhibited high

• utility for a wide spectrum of applications. In the present work, we report the facile synthesis of pyridinium based amphiphiles (1–5, Figure 1) of which amphiphiles 1 and 2 were efficient hydrogelators with minimum gelation concentrations (MGC) ≈1.7–2.0%, w/v. Modification of certain features of the