Facile access to pyridinium-based bent aromatic amphiphiles: nonionic surface modification of nanocarbons in water

• Lorenzo Catti,
• Shinji Aoyama and
• Michito Yoshizawa

Beilstein J. Org. Chem. 2024, 20, 32–40, doi:10.3762/bjoc.20.5

• both their biological and material applications, but so far has mainly relied on covalent modifications or amphiphiles featuring ionic side-chains. Here, we report a facile 2–4-step synthesis of pyridinium-based, bent aromatic amphiphiles with modular nonionic side-chains (i.e., CH3 and CH2CH2(OCH2CH2

• )2–Y (Y = OCH3, OH, and imidazole)). The new amphiphiles quantitatively self-assemble into ≈2 nm-sized aromatic micelles in water independent of the side-chain. Importantly, efficient water-solubilization and nonionic surface modification of various nanocarbons (e.g., fullerene C60, carbon nanotubes

• , and graphene nanoplatelets) are achieved through noncovalent encircling with the bent amphiphiles. The resultant imidazole-modified nanocarbons display a pH-responsive surface charge, as evidenced by NMR and zeta-potential measurements. In addition, solubilization of a nitrogen-doped nanocarbon (i.e

Synthesis of ether lipids: natural compounds and analogues

• Marco Antônio G. B. Gomes,
• Alicia Bauduin,
• Chloé Le Roux,
• Romain Fouinneteau,
• Wilfried Berthe,
• Mathieu Berchel,
• Hélène Couthon and
• Paul-Alain Jaffrès

Beilstein J. Org. Chem. 2023, 19, 1299–1369, doi:10.3762/bjoc.19.96

• compounds. Keywords: amphiphiles; edelfosine; GAEL; glycerol lipids; glycolipids; ohmline; plasmalogen; Introduction Ether lipids (ELs) are natural compounds that feature a glycerol unit linked with an ether function to an alkyl (alkyl acyl ether lipid) or alkenyl (plasmalogen) lipid chain. For the

pH-Responsive fluorescent supramolecular nanoparticles based on tetraphenylethylene-labelled chitosan and a six-fold carboxylated tribenzotriquinacene

• Nan Yang,
• Yi-Yan Zhu,
• Wei-Xiu Lin,
• Yi-Long Lu and
• Wen-Rong Xu

Beilstein J. Org. Chem. 2023, 19, 635–645, doi:10.3762/bjoc.19.45

• -soluble bowl-shaped six-fold carboxylated tribenzotriquinacene derivative TBTQ-C6 via host–guest binding. The spherical nanoparticles formed by CS-TPE amphiphiles or TBTQ-C6/CS-TPE supra-amphiphiles disintegrated under alkaline stimulation at pH 10.4 and the dispersion of the aggregates after the collapse

• water. The anionic bowl-shaped tribenzotriquinacene derivative TBTQ-C6 was incorporated into the polycationic CS-TPE to form electrostatically induced host–guest supra-amphiphiles, which further self-assembled into supramolecular nanoparticles in aqueous medium driven by the hydrophobic effect. As

• their surface charge distribution. The measurements revealed that they all had negatively charged surfaces with average zeta potentials of −1.5 mV, −10.9 mV, and −12.2 mV, respectively. These results suggested that CS-TPE obtained from higher Rf could form more stable polymeric supra-amphiphiles with

Insight into oral amphiphilic cyclodextrin nanoparticles for colorectal cancer: comprehensive mathematical model of drug release kinetic studies and antitumoral efficacy in 3D spheroid colon tumors

• Sedat Ünal,
• Gamze Varan,
• Juan M. Benito,
• Yeşim Aktaş and
• Erem Bilensoy

Beilstein J. Org. Chem. 2023, 19, 139–157, doi:10.3762/bjoc.19.14

• primarily responsible for the anticancer action [8][14][16][17][18]. To avoid CPT inactivation at alkaline medium, the concept that the lactone form can be kept stable by being encapsulated in an acidic microenvironment is also fascinating. Custom synthesized polycationic cyclodextrin amphiphiles have shown

Constrained thermoresponsive polymers – new insights into fundamentals and applications

• Patricia Flemming,
• Alexander S. Münch,
• Andreas Fery and
• Petra Uhlmann

Beilstein J. Org. Chem. 2021, 17, 2123–2163, doi:10.3762/bjoc.17.138

Synthesis and physicochemical evaluation of fluorinated lipopeptide precursors of ligands for microbubble targeting

• Masayori Hagimori,
• Estefanía E. Mendoza-Ortega and
• Marie Pierre Krafft

Beilstein J. Org. Chem. 2021, 17, 511–518, doi:10.3762/bjoc.17.45

• , including dendronized iron oxide nanoparticles [38] and nanodiamonds [39]) efficiently reinforce the interfacial film cohesion, thus enhancing the stability of the MBs. Various types of perfluoroalkylated amphiphiles have been reported that were designed for biomedical applications and display highly

Supramolecular polymerization of sulfated dendritic peptide amphiphiles into multivalent L-selectin binders

• David Straßburger,
• Svenja Herziger,
• Katharina Huth,
• Moritz Urschbach,
• Rainer Haag and
• Pol Besenius

Beilstein J. Org. Chem. 2021, 17, 97–104, doi:10.3762/bjoc.17.10

• self-assembly turns out to be crucial in obtaining supramolecular polymers suitable for interactions with biological targets [16]. Peptide amphiphiles provide access to supramolecular structures in this competitive environment by taking advantage of nature’s versatile toolbox of noncovalent

• achieved. As specific biological interactions strongly rely on the receptor–ligand interplays, we are interested in investigating the targeting of isolated receptors by supramolecular polymers built from peptide amphiphiles decorated with suitable ligand structures. The well-known L-selectin described

• above represents an excellent target that can be addressed by the multivalent presentation of sulfate groups. We therefore aim for the synthesis of sulfate-modified peptide amphiphiles to gain access to sulfated supramolecular polymers via self-assembly in water. The versatility of supramolecular

Control over size, shape, and photonics of self-assembled organic nanocrystals

• Chen Shahar,
• Yaron Tidhar,
• Yunmin Jung,
• Haim Weissman,
• Sidney R. Cohen,
• Ronit Bitton,
• Iddo Pinkas,
• Gilad Haran and
• Boris Rybtchinski

Beilstein J. Org. Chem. 2021, 17, 42–51, doi:10.3762/bjoc.17.5

• ). Convenient control over the structure and function of organic nanocrystals can enhance their utility in new and developed technologies. Keywords: aromatic amphiphiles; exciton diffusion; organic nanocrystals; perylene diimides; self-assembly; Introduction Semiconductor and metal nanoparticles exhibit size

Selected peptide-based fluorescent probes for biological applications

• Debabrata Maity

Beilstein J. Org. Chem. 2020, 16, 2971–2982, doi:10.3762/bjoc.16.247

• [56], Maity, D.; and Schmuck, C., “Fluorescent peptide beacons for the selective ratiometric detection of heparin”, Chem. – Eur. J. © 2016 Wiley‐VCH Verlag GmbH & Co. KGaA, Weinheim. A) Structure of two peptide amphiphiles 12 and 13; B) fluorescent spectra (λex = 400 nm) from a titration of the PDA

Dirhamnolipid ester – formation of reverse wormlike micelles in a binary (primerless) system

• David Liese,
• Hans Henning Wenk,
• Xin Lu,
• Jochen Kleinen and
• Gebhard Haberhauer

Beilstein J. Org. Chem. 2020, 16, 2820–2830, doi:10.3762/bjoc.16.232

• studying a lecithin/water system [20]. Gemini (bola) surfactants are a class of amphiphiles that has recently attracted a lot of attention [21][22][23][24][25]. They are made of two (or more) head groups that are connected by a spacer, that can be rigid or of variable length. In the present contribution we

Selective recognition of ATP by multivalent nano-assemblies of bisimidazolium amphiphiles through “turn-on” fluorescence response

• Rakesh Biswas,
• Surya Ghosh,
• Shubhra Kanti Bhaumik and
• Supratim Banerjee

Beilstein J. Org. Chem. 2020, 16, 2728–2738, doi:10.3762/bjoc.16.223

• µM) and PBIm14 (30 µM) the values were 2.3 and 5.8, respectively (Figure 3d). It is noteworthy to mention here that for each of the amphiphiles, the best response was obtained at an optimum concentration of the amphiphiles. For example, both at a concentration lower and higher than 75 µM, PBIm12

• adenosine phosphates (ADP and AMP) and pyrophosphate (PPi). The detection of ATP was also possible in the presence of 150 mM NaCl. The modular nature of the sensing platform provided by the multivalent nano-assemblies of the bisimidazolium amphiphiles can in principle be extended for the detection of other

• biologically important analytes through a structural modulation of the amphiphiles and the studies along this direction are currently in progress in our group. Experimental Materials and methods All starting materials were purchased from commercially available sources and used without further purification. All

Enzyme-instructed morphological transition of the supramolecular assemblies of branched peptides

• Dongsik Yang,
• Hongjian He and
• Bing Xu

Beilstein J. Org. Chem. 2020, 16, 2709–2718, doi:10.3762/bjoc.16.221

• ][20][21][22][23][24][25][26], as mimicry of amyloids [27], in the context of intracellular phase transition [28], and in molecular imaging [29][30]. Most of these studies are centered on peptide amphiphiles or amphiphilic peptides that are linear in geometry. Nature, however, also produces and

• peptides has received limited attention [2][32][33][34][35][36][37]. For example, Stupp et al. reported that a cell adhesion epitope, RGDS, acts as a branch to peptide amphiphiles for making hydrogels via self-assembly [34][36]. Ulijn et al. connected Fmoc-DAARRGG to a lysine side chain for incorporation

Easy, efficient and versatile one-pot synthesis of Janus-type-substituted fullerenols

• Marius Kunkel and
• Sebastian Polarz

Beilstein J. Org. Chem. 2019, 15, 901–905, doi:10.3762/bjoc.15.87

• . These fullerenol amphiphiles can serve as suitable precursors for further reactions resulting in new applications for fullerenols. Keywords: amphiphile; C60Cl6; fullerene; fullerenol; one-pot; Introduction The roman god Janus, who is typically depicted with two faces, metaphorically stands for duality

• the characterization of Janus-type fullerenol amphiphiles more than one method is needed to perfectly identify the compounds. Polyhydroxylation reaction of the fullerene can lead to a mixture of several oxygen moieties like hydroxy groups, diols, ketones, hemiketals, epoxides and ethers. The general

• amphiphiles. The reaction includes a wide range of primary amines reaching from aliphatic amines over aromatic amines to further functionalized amines. All resulting compounds have the general formula (OH)19+/−3C60(HNR)5, whereas, mainly hydroxy and ether moieties are included. They have been characterized

Ammonium-tagged ruthenium-based catalysts for olefin metathesis in aqueous media under ultrasound and microwave irradiation

• Łukasz Gułajski,
• Andrzej Tracz,
• Katarzyna Urbaniak,
• Stefan J. Czarnocki,
• Michał Bieniek and
• Tomasz K. Olszewski

Beilstein J. Org. Chem. 2019, 15, 160–166, doi:10.3762/bjoc.15.16

• in water including the development of specially designed water-soluble catalysts [21][22][23][24][25][26][27][28], addition of organic solvents [29][30][31], or use of additives such as for example calixarenes or cyclodextrins [32][33], chloride salts [34], vitamin E-based amphiphiles [35

Synthesis of a water-soluble 2,2′-biphen[4]arene and its efficient complexation and sensitive fluorescence enhancement towards palmatine and berberine

• Xiayang Huang,
• Xinghua Zhang,
• Tianxin Qian,
• Junwei Ma,
• Lei Cui and
• Chunju Li

Beilstein J. Org. Chem. 2018, 14, 2236–2241, doi:10.3762/bjoc.14.198

• delivery, supramolecular amphiphiles, etc. Experimental 2,2’-OEtBP4 was synthesized according to our previously reported method [47]. P and B were purchased from Shanghai Aladdin Bio-Chem Technology Co.,LTD. 1H NMR and 13C NMR spectra were recorded on a Bruker AV500 instrument. The fluorescence emission

Synthesis of new p-tert-butylcalix[4]arene-based polyammonium triazolyl amphiphiles and their binding with nucleoside phosphates

• Vladimir A. Burilov,
• Guzaliya A. Fatikhova,
• Mariya N. Dokuchaeva,
• Ramil I. Nugmanov,
• Diana A. Mironova,
• Pavel V. Dorovatovskii,
• Victor N. Khrustalev,
• Svetlana E. Solovieva and
• Igor S. Antipin

Beilstein J. Org. Chem. 2018, 14, 1980–1993, doi:10.3762/bjoc.14.173

Chemical systems, chemical contiguity and the emergence of life

• Terrence P. Kee and
• Pierre-Alain Monnard

Beilstein J. Org. Chem. 2017, 13, 1551–1563, doi:10.3762/bjoc.13.155

• of RNAs for catalytic activity, which often requires the presence of high ion concentrations that are disruptive for the formation of primitive membrane models. Membranes composed of putatively prebiotic amphiphiles, such as single hydrocarbon chain species [20][21] may have been exemplars of such

• acids and permit their oligomerization, as well as to synthesize other compounds essential to life, such as amphiphiles, the proposed building blocks of prebiotic compartments, which can then self-assemble into vesicles under the same experimental conditions [48]. Pyrophosphites could thus be considered

• processes [50]. In the case of amphiphiles, these phenomena lead to the formation of compartments by self-assembly, which can encapsulate other solutes, e.g., RNA [17][51]. The accumulation ability of porous minerals allows for the amphiphile concentration to surpass their critical vesicle concentration to

Framing major prebiotic transitions as stages of protocell development: three challenges for origins-of-life research

• Ben Shirt-Ediss,
• Sara Murillo-Sánchez and
• Kepa Ruiz-Mirazo

Beilstein J. Org. Chem. 2017, 13, 1388–1395, doi:10.3762/bjoc.13.135

• the field: Challenge 1: coupling chemistry with vesicle dynamics. A special effort should be made to discover simple reaction networks whose products include amphiphiles or surfactant molecules that can be spontaneously absorbed by pre-existing vesicles, modifying their basic properties (e.g., their

Pd- and Cu-catalyzed approaches in the syntheses of new cholane aminoanthraquinone pincer-like ligands

• Nikolay V. Lukashev,
• Gennadii A. Grabovyi,
• Dmitry A. Erzunov,
• Alexey V. Kazantsev,
• Gennadij V. Latyshev,
• Alexei D. Averin and
• Irina P. Beletskaya.

Beilstein J. Org. Chem. 2017, 13, 564–570, doi:10.3762/bjoc.13.55

• hydrophobic face permit bile acids to act as facial amphiphiles [3]. Their carboxylic and hydroxy groups can be easily modified, and the chemistry of these processes has been thoroughly studied [4]. All these options make bile acids the molecules of choice for many applications. The choice of bile acids as

A self-assembled cyclodextrin nanocarrier for photoreactive squaraine

• Ulrike Kauscher and
• Bart Jan Ravoo

Beilstein J. Org. Chem. 2016, 12, 2535–2542, doi:10.3762/bjoc.12.248

• . Amphiphilic β-cyclodextrins substituted with 7 dodecylsulfide groups on the primary side and 7 oligo(ethylene glycol) units on the secondary side were obtained via a straightforward three step synthesis as described [27][30]. A thin film of these amphiphiles was obtained by evaporation of a chloroform

Cationic Pd(II)-catalyzed C–H activation/cross-coupling reactions at room temperature: synthetic and mechanistic studies

• Takashi Nishikata,
• Alexander R. Abela,
• Shenlin Huang and
• Bruce H. Lipshutz

Beilstein J. Org. Chem. 2016, 12, 1040–1064, doi:10.3762/bjoc.12.99

• ) [121][177][178], several other amphiphiles that are both less costly and are items of commerce gave comparable results. Using commercialy available Brij 35 (2 wt %) in water [179][180][181][182][183] afforded the best levels of conversion and thus, overall yields, while in its absence (i.e.,”on water

Stimuli-responsive HBPS-g-PDMAEMA and its application as nanocarrier in loading hydrophobic molecules

• Yongsheng Chen,
• Li Wang,
• Haojie Yu,
• Zain-Ul-Abdin,
• Ruoli Sun,
• Guanghui Jing,
• Rongbai Tong and
• Zheng Deng

Beilstein J. Org. Chem. 2016, 12, 939–949, doi:10.3762/bjoc.12.92

• fluorescence-sensitive molecule, is often used for detecting the local polarity of amphiphiles. To prepare the pyrene/HBPS-g-PDMAEMA aqueous sample solutions, 5 to 6 mg pyrene was added in 5 mL HBPS-g-PDMAEMA solution with concentrations from 0 to 10.0 mg/mL followed by agitation for 2 h and filtration through

From steroids to aqueous supramolecular chemistry: an autobiographical career review

• Bruce C. Gibb

Beilstein J. Org. Chem. 2016, 12, 684–701, doi:10.3762/bjoc.12.69

• hydrophilic portal region, then dimerization of the host will not occur. For example the binding of charged amphiphiles such as n-octanoate lead to 1:1 complexes [33][34]. With these two points noted, a wide range of guests trigger dimerization to form the capsule with ostensibly sixteen negative charges on

Enabling technologies and green processes in cyclodextrin chemistry

• Giancarlo Cravotto,
• Marina Caporaso,
• Laszlo Jicsinszky and
• Katia Martina

Beilstein J. Org. Chem. 2016, 12, 278–294, doi:10.3762/bjoc.12.30

• and a high electrochemical response [74]. CuAAC has been successfully used to immobilize molecules on polymers and biopolymers as well as to join sugars to peptides and proteins. CD-polyglycerol dendron amphiphiles (CD-PG) have also been obtained. This derivative showed high encapsulation efficiency

Chemoselective O-acylation of hydroxyamino acids and amino alcohols under acidic reaction conditions: History, scope and applications

• Tor E. Kristensen

Beilstein J. Org. Chem. 2015, 11, 446–468, doi:10.3762/bjoc.11.51

• recognized procedure for large-scale preparation of many useful side-chain derivatives of hydroxyamino acids and related compounds. Such derivatives are useful in peptide chemistry and drug development, as amino acid amphiphiles for asymmetric catalysis, and as amino acid acrylic precursors for preparation

• variety of proline polymers and proline amphiphiles, on large scale, from hydroxyproline (Scheme 9) [46]. The work was later extended into a generalized system for polymeric immobilization of proline, prolineamide, diarylprolinol and imidazolidinone chiral organocatalysts by copolymerization of a set of

• generation [29][50]. The acylating power of the medium could thus easily be adjusted by varying the CF3CO2H/CF3SO3H ratio [46]. Hundreds of grams of proline amphiphiles and acrylic proline monomers were prepared by chemoselective O-acylation of hydroxyproline with saturated, aliphatic acyl chlorides in