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

• established by 1H and 13C NMR spectroscopy as well as by IR spectroscopy and MALDI–TOF mass spectrometry. Their compositions were determined by elementary analysis. A standard set of signals typical for distal disubstituted calixarenes was found in the 1H NMR spectra of 4a and b (Supporting Information File 1

Efficient catenane synthesis by cucurbit[6]uril-mediated azide–alkyne cycloaddition

• Antony Wing Hung Ng,
• Chi-Chung Yee,
• Kai Wang and
• Ho Yu Au-Yeung

Beilstein J. Org. Chem. 2018, 14, 1846–1853, doi:10.3762/bjoc.14.158

• complex helps the CBAAC by avoiding any cycloadditions outside of the CB[6] cavity and that CBAAC can be an efficient strategy for catenane synthesis. Cat-1 and its interlocked nature were further characterized by MS2, 1H and 13C NMR spectroscopy. The PF6− salt of Cat-1 was isolated in 69% yield as a

Asymmetric synthesis of propargylamines as amino acid surrogates in peptidomimetics

• Matthias Wünsch,
• David Schröder,
• Tanja Fröhr,
• Lisa Teichmann,
• Sebastian Hedwig,
• Nils Janson,
• Clara Belu,
• Jasmin Simon,
• Shari Heidemeyer,
• Philipp Holtkamp,
• Jens Rudlof,
• Lennard Klemme,
• Alessa Hinzmann,
• Beate Neumann,
• Hans-Georg Stammler and
• Norbert Sewald

Beilstein J. Org. Chem. 2017, 13, 2428–2441, doi:10.3762/bjoc.13.240

• . Consequently it was not removed prior to the rearrangement experiments. Treatment of 11i and 11k with the mild base piperidine led to the formation of α,β-unsaturated sulfinylimines 12i and 12k. The structures of the rearranged products were proven unequivocally by 1H and 13C NMR spectroscopy and X-ray crystal

Is the tungsten(IV) complex (NEt₄)₂[WO(mnt)₂] a functional analogue of acetylene hydratase?

• Matthias Schreyer and
• Lukas Hintermann

Beilstein J. Org. Chem. 2017, 13, 2332–2339, doi:10.3762/bjoc.13.230

• through the solution for 4 h at 35 °C produced plenty of precipitate in the DNPH-exhaust solution, which was shown to be acetaldehyde dinitrophenylhydrazone 9 by 1H and 13C NMR spectroscopy. The NMR spectrum of the catalyst solution contained distinct signals for acetaldehyde (δH 2.11, 9.64; 3J(H,H) = 9.6

• 13C NMR spectroscopy, IR spectroscopy, and by its dark purple color. A diagnostic analytical property in solution is δC of C-2/3 in the mnt ligand (δC = 140.4 ppm for 1) that depends on changes in the oxidation state, particularly oxidation to [WO2(mnt)2]2− (δC = 123.3 ppm). In a preliminary

• -Markovnikov hydration [18][24][25][26][27][28]. Results and Discussion Tungsten complex (NEt4)2[WO(mnt)2] (1) was prepared according to the literature procedure from Na2WO4, Na2mnt and buffered aqueous dithionite, followed by precipitation with Et4NBr (Scheme 3a) [29]. The compound was characterized by 1H and

Diosgenyl 2-amino-2-deoxy-β-D-galactopyranoside: synthesis, derivatives and antimicrobial activity

• Henryk Myszka,
• Patrycja Sokołowska,
• Agnieszka Cieślińska,
• Andrzej Nowacki,
• Maciej Jaśkiewicz,
• Wojciech Kamysz and
• Beata Liberek

Beilstein J. Org. Chem. 2017, 13, 2310–2315, doi:10.3762/bjoc.13.227

• NaBH3CN resulted in N-ethylamino (11) and N,N-diethylamino (12) saponins, which were separated by column chromatography. An analogous reaction of 4 with 3 molar excess of propionaldehyde, followed by the reduction with NaBH3CN resulted solely in N,N-dipropylaminosaponin 13. The 1H and 13C NMR spectroscopy

18-Hydroxydolabella-3,7-diene synthase – a diterpene synthase from Chitinophaga pinensis

• Jeroen S. Dickschat,
• Jan Rinkel,
• Patrick Rabe,
• Arman Beyraghdar Kashkooli and
• Harro J. Bouwmeester

Beilstein J. Org. Chem. 2017, 13, 1770–1780, doi:10.3762/bjoc.13.171

• expressing HdS-mit yielded 26.2 mg of the pure diterpene alcohol from 100 g of fresh leaves (0.03% of fresh leaf weight). The obtained material was identical to 3 obtained by in vitro incubation of GGPP with recombinant HdS by 1H and 13C NMR spectroscopy. A compound with the same structure as determined from

A speedy route to sterically encumbered, benzene-fused derivatives of privileged, naturally occurring hexahydropyrrolo[1,2-b]isoquinoline

• Olga Bakulina,
• Alexander Ivanov,
• Vitalii Suslonov,
• Dmitry Dar’in and
• Mikhail Krasavin

Beilstein J. Org. Chem. 2017, 13, 1413–1424, doi:10.3762/bjoc.13.138

• [1][28] but never isolated) was characterized by means of 1H and 13C NMR spectroscopy as well as X-ray crystallography. The isolation, for the first time, of the Mannich-type adduct 13 between HPA and an imine clearly attests to the viability of mechanistic pathway (b) shown in Scheme 3. When left at

Nitration of 5,11-dihydroindolo[3,2-b]carbazoles and synthetic applications of their nitro-substituted derivatives

• Roman A. Irgashev,
• Nikita A. Kazin,
• Gennady L. Rusinov and
• Valery N. Charushin

Beilstein J. Org. Chem. 2017, 13, 1396–1406, doi:10.3762/bjoc.13.136

• crystallography analysis, thus supporting the data of 1H and 13C NMR spectroscopy (Figure 3). We have successfully used the reaction conditions, which have proved to be the most acceptable for the nitration of compound 1a (Table 1, entry 4), for similar transformations of others ICZ substrates 1b–j bearing

Unpredictable cycloisomerization of 1,11-dien-6-ynes by a common cobalt catalyst

• Abdusalom A. Suleymanov,
• Dmitry V. Vasilyev,
• Valentin V. Novikov,
• Yulia V. Nelyubina and
• Dmitry S. Perekalin

Beilstein J. Org. Chem. 2017, 13, 639–643, doi:10.3762/bjoc.13.62

• structure to that of 1a,b. We can speculate that COOEt groups of 1l formed a chelate complex with ZnI2 and therefore strongly diminished its Lewis acidity, which is necessary for catalyst activation. All the compounds obtained were characterized by 1H and 13C NMR spectroscopy as well as high-resolution mass

Mutagenic activity of quaternary ammonium salt derivatives of carbohydrates

• Barbara Dmochowska,
• Karol Sikora,
• Anna Woziwodzka,
• Jacek Piosik and
• Beata Podgórska

Beilstein J. Org. Chem. 2016, 12, 1434–1439, doi:10.3762/bjoc.12.138

• ammonium salt (QAS) derivatives of glucopyranosides with an elongated hydrophobic hydrocarbon chain. The new N-[6-(β-D-glucopyranosyloxy)hexyl]ammonium bromides and their O-acetyl derivatives were analyzed via 1H and 13C NMR spectroscopy. The mutagenic activity of the newly synthesized QAS was investigated

On the mechanism of imine elimination from Fischer tungsten carbene complexes

• Philipp Veit,
• Christoph Förster and
• Katja Heinze

Beilstein J. Org. Chem. 2016, 12, 1322–1333, doi:10.3762/bjoc.12.125

• C21H19NFe2. A tiny peak cluster at m/z = 693, assignable to the loss of CO from W(CO)5(E-2), and peaks at higher m/z ratios, assignable to tungsten clusters, are also observed when traces of oxygen/water were present. Using 1H and 13C NMR spectroscopy as well as 2D NMR (1H,1H COSY, 1H,1H NOESY, 13C,1H HSQC

Synthesis of 2,1-benzisoxazole-3(1H)-ones by base-mediated photochemical N–O bond-forming cyclization of 2-azidobenzoic acids

• Daria Yu. Dzhons and
• Andrei V. Budruev

Beilstein J. Org. Chem. 2016, 12, 874–881, doi:10.3762/bjoc.12.86

• cyclization products such as 2,1-benzisoxazole-3(1H)-one (2a) and 2-oxo-3-carboxy-3H-azepine (3a) has been reported [30]. The structure of benzisoxazole 2a was determined by IR, 1H and 13C NMR spectroscopy and by comparison of its mass spectrum with the corresponding spectrum from the NIST library (NIST

Elucidation of a masked repeating structure of the O-specific polysaccharide of the halotolerant soil bacteria Azospirillum halopraeferens Au4

• Elena N. Sigida,
• Yuliya P. Fedonenko,
• Alexander S. Shashkov,
• Nikolay P. Arbatsky,
• Evelina L. Zdorovenko,
• Svetlana A. Konnova,
• Vladimir V. Ignatov and
• Yuriy A. Knirel

Beilstein J. Org. Chem. 2016, 12, 636–642, doi:10.3762/bjoc.12.62

• , one- and two-dimensional 1H and 13C NMR spectroscopy. The following masked repeating structure of the O-specific polysaccharide was established: →3)-α-L-Rhap2Me-(1→3)-[β-D-Glcp-(1→4)]-α-D-Fucp-(1→2)-β-D-Xylp-(1→, where non-stoichiometric substituents, an O-methyl group (~45%) and a side-chain glucose

• to 2-O-methylation. Hence, Rha and Rha2Me occupied the non-reducing end in compounds 1 and 2, respectively (Scheme 1). The isolated higher-molecular mass compounds were separated by reverse-phase HPLC and demonstrated by 1H and 13C NMR spectroscopy (data not shown) to be dimeric by-products resulted

• . halopraeferens Au4 by Smith degradation (1 and 2) and solvolysis with CF3CO2H (3).a Gro indicates glycerol. 1H and 13C NMR chemical shifts of the OPS from A. halopraeferens Au4.a Supporting Information Supporting Information File 238: 1H and 13C NMR spectroscopy data of the O-specific polysaccharide and of the

Cu(I)-catalyzed N,N’-diarylation of natural diamines and polyamines with aryl iodides

• Svetlana P. Panchenko,
• Alexei D. Averin,
• Maksim V. Anokhin,
• Olga A. Maloshitskaya and
• Irina P. Beletskaya

Beilstein J. Org. Chem. 2015, 11, 2297–2305, doi:10.3762/bjoc.11.250

• described in the literature [29][33][34][35], it was possible to analyze the reaction mixtures by 1H and 13C NMR spectroscopy and in some cases the products were isolated by column chromatography on silica gel. For example, in the proton NMR spectrum of compound 9 two signals are observed in the aliphatic

Copper-mediated synthesis of N-alkenyl-α,β-unsaturated nitrones and their conversion to tri- and tetrasubstituted pyridines

• Dimitra Kontokosta,
• Daniel S. Mueller,
• Dong-Liang Mo,
• Wiktoria H. Pace,
• Rachel A. Simpson and
• Laura L. Anderson

Beilstein J. Org. Chem. 2015, 11, 2097–2104, doi:10.3762/bjoc.11.226

• of N-alkenyl-α,β-unsaturated nitrones 8 to pyridines 9, two mechanistic experiments were evaluated (Scheme 4). The conversion of nitrone 8ae to pyridine 9ae was monitored by 1H and 13C NMR spectroscopy. Surprisingly, after heating 8ae for 4 h at 140 °C in DMSO-d6, a 1:1:1 mixture of isoxazoline 15ae

Qualitative evaluation of regioselectivity in the formation of di- and tri-6-O-tritylates of α-cyclodextrin

• Keisuke Yoshikiyo,
• Yoshihisa Matsui and
• Tatsuyuki Yamamoto

Beilstein J. Org. Chem. 2015, 11, 1530–1540, doi:10.3762/bjoc.11.168

• ,6C-di-O-trityl-α-CD’s. Keywords: 1H and 13C NMR spectroscopy; quantitative analysis; regioselectivity; tritylation; ultra-fast liquid chromatography (UFLC); Introduction Regioselective modification and deprotection on the primary hydroxy side of cyclodextrins (CDs) are of great importance in

A new and convenient synthetic way to 2-substituted thieno[2,3-b]indoles

• Roman A. Irgashev,
• Arseny A. Karmatsky,
• Gennady L. Rusinov and
• Valery N. Charushin

Beilstein J. Org. Chem. 2015, 11, 1000–1007, doi:10.3762/bjoc.11.112

• unequivocally by X-ray crystallography analysis, thus supporting the data of 1H and 13C NMR spectroscopy (Figure 2). The Lawesson’s reagent appears to act firstly as a source of hydrogen sulfide to reduce the C=C double bond in compound 10a, and secondly, as the thiation agent to form thieno[2,3-b]indole 12a by

Synthesis and characterization of the cyanobenzene-ethylenedithio-TTF donor

• Sandrina Oliveira,
• Dulce Belo,
• Isabel C. Santos,
• Sandra Rabaça and
• Manuel Almeida

Beilstein J. Org. Chem. 2015, 11, 951–956, doi:10.3762/bjoc.11.106

• formation of insoluble dcdb-TTF. The CNB-EDT-TTF 3 electron donor is thermally stable, not sensitive to oxygen and soluble in common solvents such as CH2Cl2, CHCl3 and AcOEt. The molecular structure and purity of the isolated compound after column chromatography were confirmed by 1H and 13C NMR spectroscopy

Multivalent polyglycerol supported imidazolidin-4-one organocatalysts for enantioselective Friedel–Crafts alkylations

• Tommaso Pecchioli,
• Manoj Kumar Muthyala,
• Rainer Haag and
• Mathias Christmann

Beilstein J. Org. Chem. 2015, 11, 730–738, doi:10.3762/bjoc.11.83

• structures were confirmed by 1H and 13C NMR spectroscopy and the functionalization degrees of 4a–c were determined by correlating the aromatic with the polyglycerol backbone protons (for details see Supporting Information File 1). The synthesis of modified imidazolidin-4-one 5 started with (S)-tyrosine

Synthesis and chemosensing properties of cinnoline-containing poly(arylene ethynylene)s

• Natalia A. Danilkina,
• Petr S. Vlasov,
• Semen M. Vodianik,
• Andrey A. Kruchinin,
• Yuri G. Vlasov and
• Irina A. Balova

Beilstein J. Org. Chem. 2015, 11, 373–384, doi:10.3762/bjoc.11.43

• of mass-average molecular weights () [17][19][25]. Therefore in order to avoid using of new unusual terms the oligomers obtained were named PAEs. The structure of oligomers 10a,b was confirmed by 1H and 13C NMR spectroscopy, FTIR spectra and CHN-elemental analysis. In FTIR spectra of compounds 10a,b

(CF₃CO)₂O/CF₃SO₃H-mediated synthesis of 1,3-diketones from carboxylic acids and aromatic ketones

• JungKeun Kim,
• Elvira Shokova,
• Victor Tafeenko and
• Vladimir Kovalev

Beilstein J. Org. Chem. 2014, 10, 2270–2278, doi:10.3762/bjoc.10.236

• following reaction with hydrazine hydrate gave the pyrazoles 6a–d in 62–76% yield. The products were identified by 1H and 13C NMR spectroscopy, microanalysis and by spectral comparison with the known compounds. The molecular structures of compounds 3с, 3u, 4a, 6b were confirmed by X-ray diffraction [26

Investigations of thiol-modified phenol derivatives for the use in thiol–ene photopolymerizations

• Sebastian Reinelt,
• Monir Tabatabai,
• Urs Karl Fischer,
• Norbert Moszner,
• Andreas Utterodt and
• Helmut Ritter

Beilstein J. Org. Chem. 2014, 10, 1733–1740, doi:10.3762/bjoc.10.180

• ). Besides FTIR, 1H and 13C NMR spectroscopy, elemental analysis and mass spectrometry was conducted for detailed characterization of all products 10a,b, 14a–c and 17. Mechanical properties of 10a,b, 14a–c and 17 employed in thiol–ene photopolymerizations. In this study we measured the flexural strength

Clicked and long spaced galactosyl- and lactosylcalix[4]arenes: new multivalent galectin-3 ligands

• Silvia Bernardi,
• Paola Fezzardi,
• Gabriele Rispoli,
• Stefania E. Sestito,
• Francesco Peri,
• Francesco Sansone and
• Alessandro Casnati

Beilstein J. Org. Chem. 2014, 10, 1672–1680, doi:10.3762/bjoc.10.175

• formation of the tetraazidocalixarene derivative 12 (1 h, 75% yield). The CuAAC conjugation reaction was carried out following exactly the same procedure as for compound 9 and allowed the isolation of 13 in very high yields (81%). Glycoconjugates 9 and 13 were fully characterized by 1H and 13C NMR

• spectroscopy, which displayed the disappearance of the alkyne protons and the appearance of the typical broad signal of 1,4-disubstituted triazole protons at 7.75–7.85 ppm (CD3OD/CDCl3). ESIMS (+) analyses showed peaks for the [M + 2Na]2+ and [M + 3Na]3+ adducts, which indicates the conjugation of all four

Tandem Cu-catalyzed ketenimine formation and intramolecular nucleophile capture: Synthesis of 1,2-dihydro-2-iminoquinolines from 1-(o-acetamidophenyl)propargyl alcohols

• Gadi Ranjith Kumar,
• Yalla Kiran Kumar,
• Ruchir Kant and
• Maddi Sridhar Reddy

Beilstein J. Org. Chem. 2014, 10, 1255–1260, doi:10.3762/bjoc.10.125

• without purification. NMR spectra were recorded with a 300 or 400 MHz spectrometer for 1H NMR, 75 or 100 MHz for 13C NMR spectroscopy. Chemical shifts are reported relative to tetramethylsilane in CDCl3 or to residual signals of undeuterasted solvent CDCl3/DMSO-d6 for 1H and 13C NMR spectroscopy

Cuevaenes C–E: Three new triene carboxylic derivatives from Streptomyces sp. LZ35ΔgdmAI

• Jing-Jing Deng,
• Chun-Hua Lu,
• Yao-Yao Li,
• Shan-Ren Li and
• Yue-Mao Shen

Beilstein J. Org. Chem. 2014, 10, 858–862, doi:10.3762/bjoc.10.82

• for 48 h for antifungal activity and at 37 °C for 24 h for antibacterial activity and examined for the presence of a zone of inhibition. Cuevaenes A–E (1–5) isolated from Streptomyces sp. LZ35. Selected NOESY correlations of compounds 1, 3 and 4, 5. 1H and 13C NMR spectroscopy data for compounds 3, 4