Anion exchange resins in phosphate form as versatile carriers for the reactions catalyzed by nucleoside phosphorylases

• Julia N. Artsemyeva,
• Ekaterina A. Remeeva,
• Tatiana N. Buravskaya,
• Irina D. Konstantinova,
• Roman S. Esipov,
• Anatoly I. Miroshnikov,
• Natalia M. Litvinko and
• Igor A. Mikhailopulo

Beilstein J. Org. Chem. 2020, 16, 2607–2622, doi:10.3762/bjoc.16.212

• attracted our interest in this compound [57]. It was found that in the presence of QAE Sephadex A-25, BAPR formation reached 67%, while in the case of BIO-RAD AG 1-X2 and DEAE-Cellulose, the yield was 25 and 23%, respectively. Quite unexpectedly in the experiment with Dowex-nPi the conversion of the base

Synthesis of novel fluorinated building blocks via halofluorination and related reactions

• Attila Márió Remete,
• Tamás T. Novák,
• Melinda Nonn,
• Matti Haukka,
• Ferenc Fülöp and
• Loránd Kiss

Beilstein J. Org. Chem. 2020, 16, 2562–2575, doi:10.3762/bjoc.16.208

• (rac)-11b was unequivocally established by single-crystal X-ray diffraction (Figure 1). Then, the preparation of another model compound, the trans-annelated bicyclic carbamide derivative (rac)-13, was attempted. This compound was also unknown in the literature. In the reaction of commercially available

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

• sugar-functionalized derivative TBTQ-(OG)6 in 80% yield. The solubility of this compound was completely different from that of its acetylated precursor: it exhibited good solubility in DMF, DMSO, toluene/DMSO 1:1 (v/v) as well as in water. Structural characterization. All synthesized compounds were

Conformational preferences of fluorine-containing agrochemicals and their implications for lipophilicity prediction

• Daniela Rodrigues Silva,
• Joyce K. Daré and
• Matheus P. Freitas

Beilstein J. Org. Chem. 2020, 16, 2469–2476, doi:10.3762/bjoc.16.200

• conformational equilibrium of penoxsulam (I, Figure 1). This compound has a 1,2–disubstituted ethane motif that could adopt three main staggered conformations, namely Igg, Iag and Iga (g = gauche and a = anti; see Figure 1), thus we have explored the intramolecular interactions governing its conformational

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

• , starting from the literature-known dichloro NDI 1 having two 3-dimethylaminopropyl groups attached to the imide nitrogens [31]. This compound was first methylated at the nitrogen atoms by the reaction with iodomethane in refluxing toluene, giving the diammonium NDI 2 in a very good yield of 89%. In the

On the hydrolysis of diethyl 2-(perfluorophenyl)malonate

• Ilya V. Taydakov and
• Mikhail A. Kiskin

Beilstein J. Org. Chem. 2020, 16, 1863–1868, doi:10.3762/bjoc.16.153

• surprise, 2-(perfluorophenyl)malonic acid (2) was not described in the literature to date. The only reference to this compound actually concerned the formation of the anion from diethyl 2-(perfluorophenyl)malonate (3) with excess NaH [21]. At the same time, diethyl 2-(perfluorophenyl)malonate (3) is a

Synthesis, docking study and biological evaluation of ᴅ-fructofuranosyl and ᴅ-tagatofuranosyl sulfones as potential inhibitors of the mycobacterial galactan synthesis targeting the galactofuranosyltransferase GlfT2

• Marek Baráth,
• Jana Jakubčinová,
• Zuzana Konyariková,
• Stanislav Kozmon,
• Katarína Mikušová and
• Maroš Bella

Beilstein J. Org. Chem. 2020, 16, 1853–1862, doi:10.3762/bjoc.16.152

• that given the high concentration of this compound required to achieve inhibitory effects on the galactan synthesis, this approach requires further optimization. Indeed, our pilot docking study was performed with compounds initially targeted at the transition state of GnT-I. Moreover, presented

Nonenzymatic synthesis of anomerically pure, mannosyl-based molecular probes for scramblase identification studies

• Giovanni Picca,
• Markus Probst,
• Simon M. Langenegger,
• Oleg Khorev,
• Peter Bütikofer,
• Anant K. Menon and
• Robert Häner

Beilstein J. Org. Chem. 2020, 16, 1732–1739, doi:10.3762/bjoc.16.145

• target compounds MPC-1 and MPC-2 was the preparation of the phosphoramidite β-4Ac-Man-CEP (Figure 4). Two points are of particular importance for the synthesis of this compound. Firstly, we needed access to an anomerically pure starting material, i.e., 2,3,4,6-tetra-O-acetyl-β-ᴅ-mannopyranose. This was

Rearrangement of o-(pivaloylaminomethyl)benzaldehydes: an experimental and computational study

• Csilla Hargitai,
• Györgyi Koványi-Lax,
• Tamás Nagy,
• Péter Ábrányi-Balogh,
• András Dancsó,
• Gábor Tóth,
• Judit Halász,
• Angéla Pandur,
• Gyula Simig and
• Balázs Volk

Beilstein J. Org. Chem. 2020, 16, 1636–1648, doi:10.3762/bjoc.16.136

• upfield aromatic δH(7) value (5.71 ppm) was measured for the isoindoline moiety of this compound, i.e., a diamagnetic shift of ca. 1.8 ppm occurred in this position. In order to explain this phenomenon, we should consider the anisotropic effect of the aromatic rings. Such steric arrangement is only

• , and recrystallized from EtOAc/hexane to afford the title compounds as white solids. N-[(5-Formyl-2H-1,3-benzodioxol-4-yl)methyl]-2,2-dimethylpropanamide (2a) [1]. Method A: This compound was prepared according to general procedure I using 1a [2] (1.02 g, 3.88 mmol) and TFA (30 µL, 44 mg, 0.39 mmol

• C14H17NO4 (263.29): N, 5.32; H, 6.51; C, 63.87; found: N, 5.38; H, 6.44; C, 63.77%; NMR data are identical with those published earlier [1]. Method B: This compound was prepared according to general procedure II using 1a [2] (1.00 g, 3.80 mmol) and TFA (29 µL, 43 mg, 0.38 mmol). The title compound (592 mg

Antibacterial scalarane from Doriprismatica stellata nudibranchs (Gastropoda, Nudibranchia), egg ribbons, and their dietary sponge Spongia cf. agaricina (Demospongiae, Dictyoceratida)

• Cora Hertzer,
• Stefan Kehraus,
• Nils Böhringer,
• Fontje Kaligis,
• Robert Bara,
• Dirk Erpenbeck,
• Gert Wörheide,
• Till F. Schäberle,
• Heike Wägele and
• Gabriele M. König

Beilstein J. Org. Chem. 2020, 16, 1596–1605, doi:10.3762/bjoc.16.132

• of this compound. In general, scalarane sesterterpenes are bioactive metabolites, mainly isolated from marine sources, such as Dictyoceratida sponges and the nudibranchs that feed on them [7][25][29][33][56]. So far, only six scalaranes containing cyclopropane rings, constructed of C-4, C-19 and C-20

4-Hydroxy-3-methyl-2(1H)-quinolone, originally discovered from a Brassicaceae plant, produced by a soil bacterium of the genus Burkholderia sp.: determination of a preferred tautomer and antioxidant activity

• Dandan Li,
• Naoya Oku,
• Yukiko Shinozaki,
• Yoichi Kurokawa and
• Yasuhiro Igarashi

Beilstein J. Org. Chem. 2020, 16, 1489–1494, doi:10.3762/bjoc.16.124

• -hydroxy-3-methyl-2(1H)-quinolone (1, Figure 1). This compound was recently reported from the root of woad (Isatis tinctoria, family Brassicaceae) with no details of structure characterization [17]. Herein we describe the isolation, unequivocal structure characterization, and antioxidant activity of

Synthesis and properties of quinazoline-based versatile exciplex-forming compounds

• Rasa Keruckiene,
• Simona Vekteryte,
• Ervinas Urbonas,
• Matas Guzauskas,
• Eigirdas Skuodis,
• Dmytro Volyniuk and
• Juozas V. Grazulevicius

Beilstein J. Org. Chem. 2020, 16, 1142–1153, doi:10.3762/bjoc.16.101

• ) which is usually detected for materials exhibiting low-intensity emissions [22][23]. Exciplex-forming properties Since compound 1 was characterized by the most blue-shifted fluorescence in the solid-state and a high first triplet energy level of 2.97 eV (Figure 5a and Figure 7a), this compound was

Fluorinated phenylalanines: synthesis and pharmaceutical applications

• Laila F. Awad and
• Mohammed Salah Ayoup

Beilstein J. Org. Chem. 2020, 16, 1022–1050, doi:10.3762/bjoc.16.91

• capture therapy (BNCT) [53][88][89][90][91][92]. This compound was used for PET imaging of melanoma in animal models. The low affinity of 178 for the ʟ-type amino acid transporter1 (LAT1), however, limited the use of this compound as PET radiotracer for brain tumor imaging [93][94][95][96]. Therefore, for

Aryl-substituted acridanes as hosts for TADF-based OLEDs

• Naveen Masimukku,
• Dalius Gudeika,
• Oleksandr Bezvikonnyi,
• Ihor Syvorotka,
• Rasa Keruckiene,
• Dmytro Volyniuk and
• Juozas V. Grazulevicius

Beilstein J. Org. Chem. 2020, 16, 989–1000, doi:10.3762/bjoc.16.88

• values were estimated as 2.54 eV for 4, and 2.67 eV for 3 and 6. The triplet energy could not be estimated for derivative 5, since the phosphorescence at 77 K was practically undetectable for this compound. Electrochemical and photoelectrical properties The electrochemical properties of the acridane

Cation-induced ring-opening and oxidation reaction of photoreluctant spirooxazine–quinolizinium conjugates

• Phil M. Pithan,
• Sören Steup and
• Heiko Ihmels

Beilstein J. Org. Chem. 2020, 16, 904–916, doi:10.3762/bjoc.16.82

• photochromism, i.e., a blue shift of the absorption maximum of the merocyanine form [5][19][27][28][29], and increased stability of the latter towards the thermal back reaction [21][28][30][31][32][33][34]. In this context, the complexation of metal cations has also been exploited to utilize this compound class

Synthesis of disparlure and monachalure enantiomers from 2,3-butanediacetals

• Adam Drop,
• Hubert Wojtasek and
• Bożena Frąckowiak-Wojtasek

Beilstein J. Org. Chem. 2020, 16, 616–620, doi:10.3762/bjoc.16.57

• ensure the required configuration of the asymmetric centers determining the biological activity of this compound. They include the use of naturally occurring chiral substrates, such as ʟ-glutamic acid [13], ʟ-tartaric acid [14][15][16], ᴅ-glucose [17], and sorbitol [18] as starting materials, as well as

• –8 are obtained. We therefore decided to apply this compound for the synthesis of both enantiomers of disparlure and both enantiomers of monachalure. Results and Discussion Compound 14 was prepared and converted to 15 by Fukuyama reduction as described previously [37]. The overall yield for the

• 19 instead. This compound was obtained from both aldehyde 15 and its precursor ethyl thioester methyl ester 14, respectively (Scheme 3). Both substrates 14 and 15 were reduced to the corresponding diol 17 with lithium aluminum hydride with 73% or 83% yield, respectively. Next, the selective

Regio- and stereoselective synthesis of new ensembles of diversely functionalized 1,3-thiaselenol-2-ylmethyl selenides by a double rearrangement reaction

• Svetlana V. Amosova,
• Andrey A. Filippov,
• Nataliya A. Makhaeva,
• Alexander I. Albanov and
• Vladimir A. Potapov

Beilstein J. Org. Chem. 2020, 16, 515–523, doi:10.3762/bjoc.16.47

• % yields, respectively. The one-pot synthesis of hitherto unknown bis(1,3-thiaselenol-2-ylmethyl) diselenide (8) in 90% yield from thiaselenole 1 was developed (Scheme 10). The reaction proceeded via the formation of thiaselenole selenocyanate 4, which was in situ converted into diselenide 8. This compound

Visible-light-induced addition of carboxymethanide to styrene from monochloroacetic acid

• Kaj M. van Vliet,
• Nicole S. van Leeuwen,
• Albert M. Brouwer and
• Bas de Bruin

Beilstein J. Org. Chem. 2020, 16, 398–408, doi:10.3762/bjoc.16.38

• traditional reactivity of this compound. Here, we investigated the possibility of applying monochloroacetic acid as a substrate for photoredox catalysis with styrene to directly produce γ-phenyl-γ-butyrolactone. Instead of using nucleophilic substitution, we cleaved the carbon chlorine bond by single-electron

• monochloroacetic acid have been published. The production of basic building blocks like glycine [5] (>600 000 tons/year in China in 2015) and diethyl malonate from monochloroacetic acid show the value of this compound as a starting material. Many reactions with monochloroacetic acid, including the synthesis of

The reaction of arylmethyl isocyanides and arylmethylamines with xanthate esters: a facile and unexpected synthesis of carbamothioates

• Narasimhamurthy Rajeev,
• Toreshettahally R. Swaroop,
• Ahmad I. Alrawashdeh,
• Shofiur Rahman,
• Abdullah Alodhayb,
• Seegehalli M. Anil,
• Kuppalli R. Kiran,
• Chandra,
• Paris E. Georghiou,
• Kanchugarakoppal S. Rangappa and
• Maralinganadoddi P. Sadashiva

Beilstein J. Org. Chem. 2020, 16, 159–167, doi:10.3762/bjoc.16.18

• of the final products were detected in the NMR spectra, and a representative DFT computational analysis conducted with 4c (this compound also yielded a crystal structure) was in agreement with the ratio of the two rotamers that were observed in the corresponding NMR spectra. A mechanism was proposed

Synthesis, liquid crystalline behaviour and structure–property relationships of 1,3-bis(5-substituted-1,3,4-oxadiazol-2-yl)benzenes

• Afef Mabrouki,
• Malek Fouzai,
• Armand Soldera,
• Abdelkader Kriaa and
• Ahmed Hedhli

Beilstein J. Org. Chem. 2020, 16, 149–158, doi:10.3762/bjoc.16.17

• , compared to two-chain and shorter-chain homologues. Taking into account these observations, the inability of 2d to exhibit mesophases becomes axiomatic, since this compound is devoid of any terminal alkyl chain. X-ray patterns analysis In order to correlate the obtained results from POM and DSC, we have

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

• (i.e., a 2-bromo-6-methoxy substitution pattern) was found to lower the pKa of the azonium ion such that it fell outside the normal physiological range. The neutral version of this compound nevertheless underwent trans-to-cis photoisomerization in the presence of blue-green light and exhibited slow

Pigmentosins from Gibellula sp. as antibiofilm agents and a new glycosylated asperfuran from Cordyceps javanica

• Soleiman E. Helaly,
• Wilawan Kuephadungphan,
• Patima Phainuphong,
• Mahmoud A. A. Ibrahim,
• Kanoksri Tasanathai,
• Suchada Mongkolsamrit,
• Janet Jennifer Luangsa-ard,
• Souwalak Phongpaichit,
• Vatcharin Rukachaisirikul and
• Marc Stadler

Beilstein J. Org. Chem. 2019, 15, 2968–2981, doi:10.3762/bjoc.15.293

• were found to produce the same compound. So far, pigmentosin A (1) was reported only from lichenized fungi [20][21], and thus this is the first report of this compound stemming from another group of fungi. Recently, we have reported on the two new β-carboline alkaloid derivatives gibellamines A and B

• , respectively. Notably, 1 also weakly inhibited proliferation of HeLa KB3.1 cells, with an IC50 of 17 μg/mL. This compound was reported by Grove and co-workers [32] to be active against B. subtilis (MIC 20 μg/mL). Although both compounds showed neither nematicidal activity against C. elegans nor antibiofilm

Synthesis and optoelectronic properties of benzoquinone-based donor–acceptor compounds

• Daniel R. Sutherland,
• Nidhi Sharma,
• Georgina M. Rosair,
• Ifor D. W. Samuel,
• Ai-Lan Lee and
• Eli Zysman-Colman

Beilstein J. Org. Chem. 2019, 15, 2914–2921, doi:10.3762/bjoc.15.285

• -shifted compared to those found for 2 and 5. Charge-transfer was expected to be weaker in compound 4, where the donor groups were meta disposed with respect to the acceptor. Indeed, there was only a very poorly absorptive CT band at 370 nm for this compound, which reflected the poor conjugation between

Influence of the cis/trans configuration on the supramolecular aggregation of aryltriazoles

• Sara Tejera,
• Giada Caniglia,
• Rosa L. Dorta,
• Andrea Favero,
• Javier González-Platas and
• Jesús T. Vázquez

Beilstein J. Org. Chem. 2019, 15, 2881–2888, doi:10.3762/bjoc.15.282

• °C in a refrigerator. This temperature gave rise to an opaque gel that melted above 18 °C (Table 2). The same approach, along with reduction of the minimum gelation concentration to 1.1% w/w (in DMSO) was used to obtain a gel based on 8f. In addition, this compound proved to be an effective

• as between the triazole rings, and therefore the presence of multiple intermolecular π–π stacking and π–bromine [19] interactions. This compound precipitated in the presence of any amount of water and gelled only in DMSO at a low temperature. Compound 10 produced pseudo-crystals in DMSO/H2O (1:1, v/v

• , in black), identical to those obtained for this compound in CH3CN [15], although of lower intensity. On the other hand, the ECD spectrum of the gel instead exhibited a normal Cotton effect at 253 nm (Δε = −3.8), which, at the same time, was the wavelength of its absorption maximum (Figure 6, in blue

Skeletocutins M–Q: biologically active compounds from the fruiting bodies of the basidiomycete Skeletocutis sp. collected in Africa

• Tian Cheng,
• Clara Chepkirui,
• Cony Decock,
• Josphat C. Matasyoh and
• Marc Stadler

Beilstein J. Org. Chem. 2019, 15, 2782–2789, doi:10.3762/bjoc.15.270

• the cultures of the same fungus (i.e., the corresponding mycelial culture of the specimen that was the subject of the present study [4]) and originally from Tyromyces lacteus [6]. In these two cases, 6 was reported to be the major component of the culture extracts. Even though this compound is

• µg/mL at 50 and 110 µM substrate concentration. Although tyromycin A (6) was previously reported to be active in a similar assay against HeLa S3 cells, with IC50 values of 31 μg/mL at 50 μM substrate concentration, an IC50 value >150 μg/mL for this compound was recorded on the HeLa (KB3.1) cells