New variochelins from soil-isolated Variovorax sp. H002

• Jabal Rahmat Haedar,
• Aya Yoshimura and
• Toshiyuki Wakimoto

Beilstein J. Org. Chem. 2024, 20, 692–700, doi:10.3762/bjoc.20.63

• ) resembles those of other amphiphilic marine siderophores such as marinobactins and aquachelins exhibiting the membrane affinity [21] as well as the self-assembling ability to form iron-containing vesicles [22]. This study presents another suite of amphiphilic peptidic siderophores originating in the

Photochromic derivatives of indigo: historical overview of development, challenges and applications

• Gökhan Kaplan,
• Zeynel Seferoğlu and
• Daria V. Berdnikova

Beilstein J. Org. Chem. 2024, 20, 228–242, doi:10.3762/bjoc.20.23

• assemblies as well as precise switching of the biological activity of the photoswitchable derivative. Along these lines, in 2023, Leung and co-workers prepared amphiphilic indigo-based photoswitches and incorporated them into vesicles [88]. Irradiation of the vesicles with red light resulted in the E–Z

Perspectives on push–pull chromophores derived from click-type [2 + 2] cycloaddition–retroelectrocyclization reactions of electron-rich alkynes and electron-deficient alkenes

• Michio Yamada

Beilstein J. Org. Chem. 2024, 20, 125–154, doi:10.3762/bjoc.20.13

• chain in dimethyl sulfoxide. Furthermore, the solvent-driven shuttling motion of the macrocycle was observed to exert a discernible effect on the aggregation of the amphiphilic molecular system. In particular, changing the solvent led to the generation of interlaced nanofibers, perforated capsules, and

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

• modifications, leading to irreversible property changes (Figure 1a, left) [3][4] and noncovalent wrapping with ii) linear/planar amphiphiles bearing ionic side-chains [5][6] or iii) amphiphilic/polar polymers, displaying low to moderate interactions and debundling efficiency (Figure 1a, center and right) [7][8

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

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

• to observe the morphology of CS-TPE aggregates. At pH 5.3, CS-TPE with Rf = 2, 10 and 20 mol % assembled into homogeneous spherical nanoparticles with average diameters of 131 nm, 166 nm and 236 nm, respectively (Figure 3a–c). This assembly behavior is supposed to be caused by the amphiphilic nature

• higher-order complexes between TBTQ-C6 and CS-TPE-2% with a tendency toward polymeric supra-amphiphilic assembly. The subsequent increase in transmittance upon addition of an excess of CS-TPE-2% was probably caused by the breakdown of the supra-amphiphilic assembly. The transmittance reached its lowest

• value when the concentration of CS-TPE-2% was 48 µg/mL, where a simple inclusion complex formed between TBTQ-C6 and CS-TPE-2%. As a result, the optimal mixing ratio for the formation of TBTQ-C6/CS-TPE-2% supra-amphiphilic assembly is 0.10 mM TBTQ-C6 + 48 µg/mL CS-TPE-2%. Analogously, the optimal mixing

CuAAC-inspired synthesis of 1,2,3-triazole-bridged porphyrin conjugates: an overview

• Dileep Kumar Singh

Beilstein J. Org. Chem. 2023, 19, 349–379, doi:10.3762/bjoc.19.29

• from an amphiphilic 1,2,3-triazole-bridged porphyrin-permethyl-β-CD conjugates 131a,b was reported by Liu et al. [56] in 2015. First the porphyrin-cyclodextrin conjugates 131a,b were obtained in 90% and 70% yields, respectively, by the CuAAC click reaction between zinc(II) meso-tris(ethynylphenyl

• % yield. Furthermore, this zinc conjugate was demetallated using H3PO4 in THF to form the free-base porphyrin 148b in 90% yield. The photophysical properties of this dendronized porphyrin molecule was investigated by absorption and fluorescence spectroscopy in different solvents, and the amphiphilic

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

• in cancer-related deaths. With the current treatment possibilities, a definitive, safe, and effective treatment approach for CRC has not been presented yet. However, new drug delivery systems show promise in this field. Amphiphilic cyclodextrin-based nanocarriers are innovative and interesting

• , and furthermore in vivo antitumoral and antimetastatic efficacy in early and late-stage colon cancer models and biodistribution after single dose oral administration. This study was carried out to further elucidate oral camptothecin (CPT)-loaded amphiphilic cyclodextrin nanoparticles for the local

• pH. Preliminary studies have evidenced pKa values in the 8.3 range for non-amphiphilic surrogates of these cationic CDs, supporting the cationic character of the resulting NPs [20]. We hypothesized that these polycationic CD NPs, which we designed in our previous studies, could protect the active and

1,4-Dithianes: attractive C2-building blocks for the synthesis of complex molecular architectures

• Bram Ryckaert,
• Ellen Demeyere,
• Frederick Degroote,
• Hilde Janssens and
• Johan M. Winne

Beilstein J. Org. Chem. 2023, 19, 115–132, doi:10.3762/bjoc.19.12

• group) are especially favored here [92][93], and these allyl cations can also be seen as 1,3-dipoles, cross-conjugated by a carbonyl (Scheme 13b). As can be expected from this 1,3-dipolar nature, such amphiphilic allyl cations can also be used in (3 + 2) cycloadditions, though this has so far been

Preparation of β-cyclodextrin/polysaccharide foams using saponin

• Max Petitjean and
• José Ramón Isasi

Beilstein J. Org. Chem. 2023, 19, 78–88, doi:10.3762/bjoc.19.7

• ]. Saponins, because of their amphiphilic nature, are known as natural surfactants [9]. They have been used as natural detergents, foaming agents, stabilizers, emulsifiers and wetting agents, for example [10]. The micelles produced will be different in size and shape as a function of the type of saponin

Cholyl 1,3,4-oxadiazole hybrid compounds: design, synthesis and antimicrobial assessment

• Anas J. Rasras,
• Mohamed El-Naggar,
• Nesreen A. Safwat and
• Raed A. Al-Qawasmeh

Beilstein J. Org. Chem. 2022, 18, 631–638, doi:10.3762/bjoc.18.63

• drugs, cholic acid with its unique shape has attracted scientists’ attention by virtue of its non-toxic, natural human product, biodegradable, and amphiphilic properties. Cholic acid derivatives have been reported to have a wide range of activities such as antibacterial [21][24][25][26] and anticancer

• [27][28][29], and were used for ischemic stroke treatment [30], to decrease the cytotoxicity of anticancer drugs [31], and as amphiphilic copolymers as artificial ionophores [32]. Result and Discussion The synthetic strategy for the synthesis of the desired compounds 4a–v commenced from commercially

Site-selective reactions mediated by molecular containers

• Rui Wang and
• Yang Yu

Beilstein J. Org. Chem. 2022, 18, 309–324, doi:10.3762/bjoc.18.35

• terminal was exposed to the aqueous solution and the more hydrophobic olefin terminal was buried deep in the cavitand hence protected from the further functionalization. This methodology could be expanded generally to the systems of converting symmetrical hydrophobic guests to unsymmetrical, amphiphilic

Biological properties and conformational studies of amphiphilic Pd(II) and Ni(II) complexes bearing functionalized aroylaminocarbo-N-thioylpyrrolinate units

• Samet Poyraz,
• Samet Belveren,
• Sabriye Aydınoğlu,
• Mahmut Ulger,
• Abel de Cózar,
• Maria de Gracia Retamosa,
• Jose M. Sansano and
• H. Ali Döndaş

Beilstein J. Org. Chem. 2021, 17, 2812–2821, doi:10.3762/bjoc.17.192

• ; Introduction In recent years, metal complexes with biological activity are of paramount relevance in medicine as valuable alternatives for the classical pharmaceuticals based on organic compound scaffolds. In this line, metal complexes incorporating an amphiphilic character (also called metallosurfactants

• , antitumoral, antimalarial, antifungal, or antiviral activities [14]. In this study, as a continuation of our work related to organometallic compounds with very low/modest amphiphilic character [15][16][17], we propose the incorporation of a 3-indolylmethyl group in the ligand and compare the bioactivity

Adjusting the length of supramolecular polymer bottlebrushes by top-down approaches

• Tobias Klein,
• Franka V. Gruschwitz,
• Maren T. Kuchenbrod,
• Ivo Nischang,
• Stephanie Hoeppener and
• Johannes C. Brendel

Beilstein J. Org. Chem. 2021, 17, 2621–2628, doi:10.3762/bjoc.17.175

• benzenetrispeptide (BTP) motifs [18][19][20]. The resulting amphiphilic character of the materials facilitated a control of the kinetic assembly, which provided access to stable nanostructures on a broad length range (<100 nm–2 µm). While the process enables a good adjustment of the length, it relies on a precise

• bonding moieties are either urea-based or peptide-based (i.e., phenylalanine) units, the dodecyl chains act as hydrophobic shields to induce the amphiphilic assembly in water and prevent the surrounding water from interfering with the hydrogen bonds in the interior [29]. Attaching a hydrophilic PEO chain

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

• entropic effect characterized by negative ∆mH and ∆mS values. The essential structural feature of such polymers is their amphiphilic structure of hydrophobic domains and hydrophilic groups, which can form hydrogen bonds with water. These interactions result in a highly ordered hydration shell when the

• low viscosity, high density of polymer segments and functional groups as well as a smaller hydrodynamic radius and larger diffusion coefficient compared to linear polymer chains in solution. Amphiphilic AB-type copolymers spontaneously form micelle structures above a critical concentration by self

• absolute length of the block copolymer and the relative length of the blocks to each other and the glass transition temperature. If a block is composed of a thermoresponsive polymer, the amphiphilic character and self-assembly ability can be altered by changing the temperature. The thermoresponsive block

A comprehensive review of flow chemistry techniques tailored to the flavours and fragrances industries

• Guido Gambacorta,
• James S. Sharley and
• Ian R. Baxendale

Beilstein J. Org. Chem. 2021, 17, 1181–1312, doi:10.3762/bjoc.17.90

[2 + 1] Cycloaddition reactions of fullerene C₆₀ based on diazo compounds

• Yuliya N. Biglova

Beilstein J. Org. Chem. 2021, 17, 630–670, doi:10.3762/bjoc.17.55

• amphiphilic C60 derivatives. Treatment of 14 with oxalyl chloride gives reactive acid chloride 15. Acylation of the presynthesized (ʟ-Ala-Aib)2-ʟ-Ala-OMe peptide with compound 15 gives the expected fullerene–peptide conjugate 16 (Scheme 8). A somewhat modified version for the synthesis of peptidofullerenes is

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

• (lipopeptides) have been used as the amphiphilic components of drug delivery systems with anticancer properties, such as the tripeptide Arg–Gly–Asp (RGD) that binds to integrin αvβ3, which is expressed on endothelial cells of various malignant tumors [15][19][20][21][22]. Other lipopeptides display cell

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

• 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

Selected peptide-based fluorescent probes for biological applications

• Debabrata Maity

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

• insulin Schmuck and co-workers reported a supramolecular ensemble in combination of a pyrene-tagged amphiphilic peptide beacon (6) and a macrocyclic host (cucurbit[8]uril, CB[8]) for ratiometric fluorescent detection of amino acid derivatives, specific peptides, and proteins in aqueous media (Figure 6

• bacteria [57]. It is a glycolipid consisting of a variable polysaccharide domain connected to a conserved glucosamine-based phospholipid called lipid A. It is highly negatively charged due to two phosphorylated groups in the lipid A part and carboxylated groups in the polysaccharide part. It is amphiphilic

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

• interaction of the alkyl chains. Keywords: dirhamnolipid ester; gemini surfactant; rheology; reverse wormlike micelle (RWLM); Introduction Surfactants have both hydrophilic and hydrophobic groups and are therefore amphiphilic molecules. Due to their unique molecular structure, surfactants are essential

Easy access to a carbohydrate-based template for stimuli-responsive surfactants

• Thomas Holmstrøm,
• Daniel Raydan and
• Christian Marcus Pedersen

Beilstein J. Org. Chem. 2020, 16, 2788–2794, doi:10.3762/bjoc.16.229

• hydrophilic and a lipophilic domain, thereby rendering them amphiphilic. This dual functionality gives surfactants unique properties such as being able to stabilize emulsions (emulsifiers) or forming large self-assembled aggregates that can take the shape of, for example, micelles or liposomes [1]. The latter

• surfactants: amphiphilic molecules that can alter their properties upon an external stimulus [6]. The intelligent surfactants are not passive but designed to undergo a molecular change when it is triggered with either a change in the pH value [7][8], upon light irradiation [9] or in the presence of metal ions

• [10][11]. Common for all of the systems is that the hydrophilic head group can undergo a conformational change upon an external stimulus. The head group is typically functionalized with two lipophilic tails rendering the compound amphiphilic. The conformational change of the head group acts as a

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

• to an n-alkyl chain at the other, underwent self-assembly in aqueous media depending on the length of the alkyl segment. The amphiphilic derivatives having n-decyl or longer chains, formed nano-assemblies with cyanic–green emission resulting from the stacked pyrene chromophores in the aggregates. The

• the nucleotides occurring through multivalent electrostatic interactions in the cavity/cleft created by the spatial orientation of the imidazolium groups. We herein consider a self-assembly based approach in which amphiphilic monomers with bisimidazolium moieties are utilized to create multivalent

• buffer (Figure 2b) also showed a significant difference between PBIm4 and the three amphiphilic derivatives. For example, the amphiphilic derivatives exhibited structured emission bands around 376 nm, 396 nm and 417 nm as well as a broad structureless band centered around 480–490 nm (PBIm10: 481 nm

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

Water-soluble host–guest complexes between fullerenes and a sugar-functionalized tribenzotriquinacene assembling to microspheres

• Si-Yuan Liu,
• Xin-Rui Wang,
• Man-Ping Li,
• Wen-Rong Xu and
• Dietmar Kuck

Beilstein J. Org. Chem. 2020, 16, 2551–2561, doi:10.3762/bjoc.16.207

• hydrophobic effect and to host–guest π–π interactions. Hydrophobic surface simulations showed that TBTQ-(OG)6 and C60 forms an amphiphilic supramolecular host–guest complex, which further assembles to microspheres with diameters of 0.3–3.5 μm, as determined by scanning electron microscopy. Keywords

• of this host with C60 and C70-fullerene was investigated in co-organic solvents and in aqueous solution. The hydrophobic surface simulation of this host indicated the formation of a supra-amphiphilic system, which, as shown by scanning electron microscopy, further self-assembles into microspheres in

• of 0.3–3.5 μm were observed for the complex TBTQ-(OG)6 C60. Obviously, these aggregates form by further assembly of the supra-amphiphilic host–guest systems, as suggested in Figure 6c, due to the hydrophobic interactions governing the association behavior of TBTQ-(OG)6 C60 in water. Conclusion In