Metal-free glycosylation with glycosyl fluorides in liquid SO₂

• Krista Gulbe,
• Jevgeņija Lugiņina,
• Edijs Jansons,
• Artis Kinens and
• Māris Turks

Beilstein J. Org. Chem. 2021, 17, 964–976, doi:10.3762/bjoc.17.78

• of an ammonium salt. The 19F NMR spectra of the water-soluble components was than compared to the standard obtained from the reaction between TBAF and SO2. The peak that corresponds to the FSO2− anion was observed at 38.34 ppm (TFA as an external standard, −76.55 ppm) [77]. Also DFT calculations were

Microwave-assisted multicomponent reactions in heterocyclic chemistry and mechanistic aspects

• Shivani Gulati,
• Stephy Elza John and
• Nagula Shankaraiah

Beilstein J. Org. Chem. 2021, 17, 819–865, doi:10.3762/bjoc.17.71

A chromatography-free and aqueous waste-free process for thioamide preparation with Lawesson’s reagent

• Ke Wu,
• Yichen Ling,
• An Ding,
• Liqun Jin,
• Nan Sun,
• Baoxiang Hu,
• Zhenlu Shen and
• Xinquan Hu

Beilstein J. Org. Chem. 2021, 17, 805–812, doi:10.3762/bjoc.17.69

• in the work-up process and it was believed that the compound A was converted to a water-soluble thiophosphonate (Figure 2) [14][15][16]. Although this operation simplified the work-up procedure and allowed a scaled up chromatography-free purification, it generated quite large amounts of P-containing

[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

• itself (depending on the nature of the attached fragment) to exhibit inherent bioactive properties in a living organism. The efforts of chemists in the design and synthesis of organofunctionalized C60 derivatives for medicine are primarily focused on the creation of water-soluble compounds [18][26][27

• , conversion to water-soluble biologically active fullerene–peptide derivative 27 occurs (Scheme 12). Reactions of monophenyldiazomethanes with C60 were used in the syntheses of adducts 28, 29 [90], and 30 (Figure 2) [91]. Moreover, diphenyldiazomethanes were used for synthesizing 31 [79], 32, 33 [90], and 34

• .) Synthesis of fullerenylpeptides 23 and 24. The synthetic route to the water-soluble biologically active fullerene–peptide derivative 27. Serial synthesis of monophenylmethanofullerenes. Four-step synthesis of the [6,6]-tert-butyl phenyl-C61-butyrate 47. Synthesis of aminophenylfullerenes 49 and 51 based on

Insight into functionalized-macrocycles-guided supramolecular photocatalysis

• Minzan Zuo,
• Krishnasamy Velmurugan,
• Kaiya Wang,
• Xueqi Tian and
• Xiao-Yu Hu

Beilstein J. Org. Chem. 2021, 17, 139–155, doi:10.3762/bjoc.17.15

• reported a light-harvesting system for photocatalysis based on the water-soluble pillar[5]arene WP5 [56]. The large cavity volume of the formed nanoparticles enabled two guest β-carotene (β-CAR) and chlorophyll-b (Chl-b) molecules to be encapsulated within the cavity (Figure 18). The β-CAR and Chl-b

• photocatalysis [57]. Yang and co-workers reported the photocyclodimerization of AC with the water-soluble pillar[6]arene WP6 (Figure 19). The HH/HT yield ratio of the HH- and HT-photodimers is 0.75 in the presence of WP6, which is greatly improved compared to that without WP6 (HH/HT 0.30). This phenomenon may be

Chemical constituents of Chaenomeles sinensis twigs and their biological activity

• Joon Min Cha,
• Dong Hyun Kim,
• Lalita Subedi,
• Zahra Khan,
• Sang Un Choi,
• Sun Yeou Kim and
• Chung Sub Kim

Beilstein J. Org. Chem. 2020, 16, 3078–3085, doi:10.3762/bjoc.16.257

• 1a (1 mg). To the dried water-soluble phase were added pyridine (0.5 mL) and ʟ-cysteine methyl ester hydrochloride (0.5 mg), and the reaction mixture was stirred at 60 °C for 1 h. Then, o-tolyl isothiocyanate (0.1 mL) was added and the mixture stirred at 60 °C for another 1 h. The reaction mixture

Optical detection of di- and triphosphate anions with mixed monolayer-protected gold nanoparticles containing zinc(II)–dipicolylamine complexes

• Lena Reinke,
• Julia Bartl,
• Marcus Koch and
• Stefan Kubik

Beilstein J. Org. Chem. 2020, 16, 2687–2700, doi:10.3762/bjoc.16.219

• protonated and therefore better water-soluble would allow immobilizing it together with (R)-1. As acid, we initially used diluted nitric acid because the eventual formation of the zinc complexes with zinc(II) nitrate would anyway lead to AuNPs containing nitrate anions. Adding the acid to the NPcit solution

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

• Department of Chemistry, Center for Molecular Materials (CM2), Bielefeld University, 33615 Bielefeld, Germany 10.3762/bjoc.16.207 Abstract A sugar-functionalized water-soluble tribenzotriquinacene derivative bearing six glucose residues, TBTQ-(OG)6, was synthesized and its interaction with C60 and C70

• , and oxidative stability, has promoted the exploration of water-soluble fullerenes for biological use [34][35]. The extremely hydrophobic nature of fullerenes requires a strongly hydrophilic supramolecular host to achieve water solubility. It is important to note that host–guest research on TBTQ

• derivatives with fullerenes has been limited to organic media so far because of the poor solubility of their complexes in aqueous media. Therefore, the design, synthesis, and exploration of water-soluble TBTQ derivatives offer attractive possibilities for broadening the applications of the TBTQ structural

Recent developments in enantioselective photocatalysis

• Callum Prentice,
• James Morrisson,
• Andrew D. Smith and
• Eli Zysman-Colman

Beilstein J. Org. Chem. 2020, 16, 2363–2441, doi:10.3762/bjoc.16.197

Styryl-based new organic chromophores bearing free amino and azomethine groups: synthesis, photophysical, NLO, and thermal properties

• Anka Utama Putra,
• Deniz Çakmaz,
• Nurgül Seferoğlu,
• Alberto Barsella and
• Zeynel Seferoğlu

Beilstein J. Org. Chem. 2020, 16, 2282–2296, doi:10.3762/bjoc.16.189

• -pull dyes are promising candidate materials for optoelectronic device usages and various NLO applications and could be used for applications as water-soluble fluorescent probes for determination of pH. Experimental Materials, methods, and instrumentation Tetrabutylammonium hydroxide (TBAOH) was

Naphthalene diimide–amino acid conjugates as novel fluorimetric and CD probes for differentiation between ds-DNA and ds-RNA

• Annike Weißenstein,
• Myroslav O. Vysotsky,
• Ivo Piantanida and
• Frank Würthner

Beilstein J. Org. Chem. 2020, 16, 2032–2045, doi:10.3762/bjoc.16.170

• of the water-soluble NDIs The spectrophotometric properties of the NDIs 3a,b, and 5 were investigated in cacodylate buffer at pH 5.0 for easier comparison with complementary pH-dependent AA–fluorophores used in our previous research (PHEN–AAs [26] and GCP derivatives [27]). Additionally, the

• vacuum. Bottom: The orientation of transition dipole moments (red arrow for 450–600 nm range) according to the calculations made for the spectra shown in Figure 2. Synthesis of water-soluble naphthalene diimides 3a,b, and 5. Optical properties of 3a,b, and 5 in cacodylate buffer (pH 5.0) at 23 °C. ∆Tm

• (c = 1.0 × 10−6 M) with ct-DNA, poly(A)-poly(U), poly(dA-dT)2, and poly(dG-dC)2 at 25 °C (cacodylate buffer, pH 5.0, I = 0.05 M). Supporting Information Supporting Information File 544: Copies of 1H, 13C NMR spectra, HRMS spectra, and titration data on the binding of water-soluble NDI compounds 3a,b

An overview on disulfide-catalyzed and -cocatalyzed photoreactions

• Yeersen Patehebieke

Beilstein J. Org. Chem. 2020, 16, 1418–1435, doi:10.3762/bjoc.16.118

• disulfide-catalyzed isomerization of allyl alcohols to carbonyl compounds under high-pressure mercury lamp irradiation (λ > 300 nm) at room temperature. The yield of the reaction reached up to 91% (Scheme 23) [30]. Using the water-soluble dendrimer disulfide, the photoinduced isomerization in water was also

The charge-assisted hydrogen-bonded organic framework (CAHOF) self-assembled from the conjugated acid of tetrakis(4-aminophenyl)methane and 2,6-naphthalenedisulfonate as a new class of recyclable Brønsted acid catalysts

• Svetlana A. Kuznetsova,
• Alexander S. Gak,
• Yulia V. Nelyubina,
• Vladimir A. Larionov,
• Han Li,
• Michael North,
• Vladimir P. Zhereb,
• Alexander F. Smol'yakov,
• Artem O. Dmitrienko,
• Michael G. Medvedev,
• Igor S. Gerasimov,
• Ashot S. Saghyan and
• Yuri N. Belokon

Beilstein J. Org. Chem. 2020, 16, 1124–1134, doi:10.3762/bjoc.16.99

• homogeneous, water-soluble part of F-1. The filtered solution was catalytically active to the same extent as the initial heterogeneous one (Table 1, run 13). Thus, in this case, solid F-1 served mostly as a reservoir for the production of the soluble catalyst, although the dissolved part could easily be

Efficient synthesis of dipeptide analogues of α-fluorinated β-aminophosphonates

• Marcin Kaźmierczak and
• Henryk Koroniak

Beilstein J. Org. Chem. 2020, 16, 756–762, doi:10.3762/bjoc.16.69

• -dimethylaminopropyl)-N′-ethylcarbodiimide hydrochloride (EDCl) [41] significantly increased the reaction yield (86%). What is more, the reaction byproduct is water-soluble and easy to remove by extraction. Nevertheless, HOBt was still used as an additive. This reagent has recently been reported to exhibit explosive

Photophysics and photochemistry of NIR absorbers derived from cyanines: key to new technologies based on chemistry 4.0

• Bernd Strehmel,
• Christian Schmitz,
• Ceren Kütahya,
• Yulian Pang,
• Anke Drewitz and
• Heinz Mustroph

Beilstein J. Org. Chem. 2020, 16, 415–444, doi:10.3762/bjoc.16.40

• their water solubility; that is the sulfobutyl group in the case of R1 or -SO3− in the case of either R2 or R3. Water soluble cyanines could feasibly favor physical drying of aqueous dispersions upon irradiation with a NIR-LED [70]. In addition, chemical drying of coatings requires the use of strong

Architecture and synthesis of P,N-heterocyclic phosphine ligands

• Wisdom A. Munzeiwa,
• Bernard Omondi and
• Vincent O. Nyamori

Beilstein J. Org. Chem. 2020, 16, 362–383, doi:10.3762/bjoc.16.35

• was very low after trapping 75 with diphenylchlorophosphine [79]. The PTA motif is water soluble, thermally, air and moisture stable. The PTA building block can be synthesized by coupling tris(hydroxymethyl)phosphine (73) with formaldehyde and ammonia in ice water or with hexamethylenetetramine. A

Synthesis and characterization of bis(4-amino-2-bromo-6-methoxy)azobenzene derivatives

• David Martínez-López,
• Amirhossein Babalhavaeji,
• Diego Sampedro and
• G. Andrew Woolley

Beilstein J. Org. Chem. 2019, 15, 3000–3008, doi:10.3762/bjoc.15.296

• neutral pH, creating a doubly charged species. As anticipated, compound 5 was found to be much more water-soluble than 4. The UV–vis spectrum of 5 at a neutral pH value is shown in Figure 4. Irradiation with blue light at 440 nm produced the PSS (dotted line). Thermal reversion from the cis isomer was

Design, synthesis and investigation of water-soluble hemi-indigo photoswitches for bioapplications

• Daria V. Berdnikova

Beilstein J. Org. Chem. 2019, 15, 2822–2829, doi:10.3762/bjoc.15.275

• photochemical properties. Along these lines, special efforts have been devoted to design, for example, water-soluble derivatives of spiropyran [1][2][3], azobenzene [4][5], diarylethene [6][7][8], or chromene [9] that keep efficient photochromism in aqueous medium. Although a significant progress has been made

• in the development of water-soluble photochromes, there is still an emerging search for new types of photochromic compounds for applications in biological systems. In particular, nowadays the development of photopharmacology is based mainly on azobenzene chemistry [10][11] and, therefore, finding of

Photoreversible stretching of a BAPTA chelator marshalling Ca²⁺-binding in aqueous media

• Aurélien Ducrot,
• Arnaud Tron,
• Robin Bofinger,
• Ingrid Sanz Beguer,
• Jean-Luc Pozzo and
• Nathan D. McClenaghan

Beilstein J. Org. Chem. 2019, 15, 2801–2811, doi:10.3762/bjoc.15.273

• a water-soluble molecule which has a high affinity and selectivity for calcium, allowing binding of physiological levels of calcium, whose binding can be switched reversibly as efficiently as possible both in terms of affinity and quantum yield. In principle this would offer real-time regulation of

Iodine-mediated hydration of alkynes on keto-functionalized scaffolds: mechanistic insight and the regiospecific hydration of internal alkynes

• Zachary Lee,
• Brandon R. Jones,
• Nyochembeng Nkengbeza,
• Michael Phillips,
• Kayla Valentine,
• Alexis Stewart,
• Brandon Sellers,
• Nicholas Shuber and
• Karelle S. Aiken

Beilstein J. Org. Chem. 2019, 15, 2747–2752, doi:10.3762/bjoc.15.265

• innocuous, water-soluble byproducts, such as iodide and sulfate salts, and uses inexpensive molecular iodine to facilitate the hydration. Moreover, unlike other metal-free alkyne hydration procedures, heat and strong acids are not required [17][18][19][20]. The reaction proceeds under mild conditions at

Plasma membrane imaging with a fluorescent benzothiadiazole derivative

• Pedro H. P. R. Carvalho,
• Jose R. Correa,
• Karen L. R. Paiva,
• Daniel F. S. Machado,
• Jackson D. Scholten and
• Brenno A. D. Neto

Beilstein J. Org. Chem. 2019, 15, 2644–2654, doi:10.3762/bjoc.15.257

• application of water-soluble plasma membrane probes [17][18]. We have been developing a new class of selective bioprobes based on the derivatization of the 2,1,3-benzothiadiazole (BTD) core (Figure 1) [19][20][21][22]. After we disclosed the use of these BTD derivatives as a new class of selective

• the design, synthesis, properties and application of a new fluorogenic BTD derivative as a water-soluble selective plasma membrane probe for bioimaging experiments. Results and Discussion The new water-soluble fluorescent BTD derivative (named BTD-4APTEG) was planned and synthesized as shown in Scheme

• better conjugation with the 4AP substituent at the C4 carbon of the BTD heterocyclic core. The ionic nature of the structure in combination with a hydrophilic anion (MeSO3−, methanesulfonate) and the presence of the hydrophilic domain (triethylene glycol monomethyl ether) make the dye a water-soluble BTD

Reversible switching of arylazopyrazole within a metal–organic cage

• Anton I. Hanopolskyi,
• Soumen De,
• Michał J. Białek,
• Yael Diskin-Posner,
• Liat Avram,
• Moran Feller and
• Rafal Klajn

Beilstein J. Org. Chem. 2019, 15, 2398–2407, doi:10.3762/bjoc.15.232

• a premade complex of 2 with a tightly bound guest, tetra-o-fluoroazobenzene [49], no acceleration effect was observed. Conclusion In summary, we investigated the encapsulation and switching of a prototypical arylazopyrazole in the hydrophobic cavity of a water-soluble metal–organic cage. A host

Fluorescent phosphorus dendrimers excited by two photons: synthesis, two-photon absorption properties and biological uses

• Anne-Marie Caminade,
• Artem Zibarov,
• Eduardo Cueto Diaz,
• Aurélien Hameau,
• Maxime Klausen,
• Kathleen Moineau-Chane Ching,
• Jean-Pierre Majoral,
• Jean-Baptiste Verlhac,
• Olivier Mongin and
• Mireille Blanchard-Desce

Beilstein J. Org. Chem. 2019, 15, 2287–2303, doi:10.3762/bjoc.15.221

• water-soluble dumbbell-like dendrimers retains a similar TPA response as that of the model monomer in ethanol, as shown by σ2 values of 104 GM for G1, 119 for G2, and 127 for G3, in water [56]. The same type of synthetic method was applied to another TPA fluorophore functionalized by two phenols, but

• confinement in the double layer dendrimer has a detrimental influence on the TPA properties [63]. Biological properties of dendrimers having TPA properties Most of the water-soluble fluorescent dendrimers shown in the previous paragraphs have been synthesized for diverse biological purposes. The first type of

• high antiproliferative activities against different tumor cell lines. A fluorescent water-soluble dendrimer, applicable for two-photon photodynamic therapy and imaging. Schematization of the different types of TPA fluorescent phosphorus dendrimers and dendritic structures that have been already

Complexation of chiral amines by resorcin[4]arene sulfonic acids in polar media – circular dichroism and diffusion studies of chirality transfer and solvent dependence

• Bartosz Setner and
• Agnieszka Szumna

Beilstein J. Org. Chem. 2019, 15, 1913–1924, doi:10.3762/bjoc.15.187

• effect on stability and ordering, and, additionally we aimed to test the possibility of formation of water-soluble capsules, which are of particular interest to supramolecular chemists. Results and Discussion RSAs can be readily synthesized by the Mannich reaction of upper-rim unsubstituted resorcin[4

• ]arenes with sodium sulfite and formaldehyde according to a general synthetic procedure [15]. While the synthetic procedure for water soluble RSAs is straightforward, purification of the final products is tricky and highly substrate-dependent. RSA 1 was obtained in 92% yield after purification involving

Design, synthesis and biological evaluation of immunostimulating mannosylated desmuramyl peptides

• Rosana Ribić,
• Ranko Stojković,
• Lidija Milković,
• Mariastefania Antica,
• Marko Cigler and
• Srđanka Tomić

Beilstein J. Org. Chem. 2019, 15, 1805–1814, doi:10.3762/bjoc.15.174

• significant role in the stimulation of the immune response. In particular, compound 21 was identified, so far, as the most potent adjuvant in this class of mannosylated desmuramyl peptides. It should be also noted that the compound 21 is stable, non-pyrogenic and water-soluble what makes it potentially