Selenium halide-induced bridge formation in [2.2]paracyclophanes

• Laura G. Sarbu,
• Henning Hopf,
• Peter G. Jones and
• Lucian M. Birsa

Beilstein J. Org. Chem. 2014, 10, 2550–2555, doi:10.3762/bjoc.10.266

• in situ prepared SeCl2 [28], in chloroform at 0 °C, a mixture of unexpected addition products has been obtained (Scheme 1). After separation by column chromatography, we assigned the structures of isomeric cyclic dienes 2 and 3 and the tetrachloro derivative 4 on the basis of 2D NMR studies and mass

• [28], in chloroform at 0 °C, provided a mixture of isomeric cyclic dienes 5 and 6, and the tetrabromo derivative 7 (Scheme 1, Table 1, entry 3) in 76% yield. Again, the structures of these compounds, as well as the configuration of diene 5, have been established on the basis of 2D NMR studies, mass

Regio- and stereoselective synthesis of new diaminocyclopentanols

• Evgeni A. Larin,
• Valeri S. Kochubei and
• Yuri M. Atroshchenko

Beilstein J. Org. Chem. 2014, 10, 2513–2520, doi:10.3762/bjoc.10.262

• aminocyclopentanols 8c and 8d (Supporting Information File 1). In every experiment, 1,2-trans-2,3-cis-aminocyclopentanols, arising from opening of epoxide 3a at C1, were the only regioisomers isolated. The stereo- and regiochemistry of 8a and 8d were assigned by 2D NMR (HSQC-DEPT, 1H,1H COSY and NOESY experiments

• absence of the C(2)H-C(5)H correlation in the NOESY spectrum support the stereochemistry of 8a. The same relative configuration of 8d was assigned from 2D NMR analysis, and the stereochemistry of 8b and 8c was additionally confirmed by the comparison of 3J coupling constants of the resonances

• stereochemistry of the major regioisomers 9a–d was deduced from the analysis of 1H NMR and 2D NMR data as described for 8a–d. Assignments of CH proton resonances of 10a–d were established by 1H,13C HMBC and HSQC-DEPT experiments, and connectivity was established by the analysis of 1H,1H COSY spectra. The

Oxidative phenylamination of 5-substituted 1-hydroxynaphthalenes to N-phenyl-1,4-naphthoquinone monoimines by air and light “on water”

• Julio Benites,
• Juan Meléndez,
• Cynthia Estela,
• David Ríos,
• Luis Espinoza,
• Iván Brito and
• Jaime A. Valderrama

Beilstein J. Org. Chem. 2014, 10, 2448–2452, doi:10.3762/bjoc.10.255

• NMR, 2D NMR) and high resolution mass spectrometry (HRMS). The position of the nitrogen substituent in these aminoquinones was determined by means of HMBC experiments. Encouraged by these results, the preparation of aminojuglones 4a and 4b was attempted by employing the hypothetical one pot procedure

• )naphthalene-1(4H)-one (6, 98% yield). Under similar conditions, but using green LEDs light radiation, compound 6 was isolated in 80% yield. The structure of 6 was established by means of 1D and 2D NMR and by X-ray crystallographic studies (Figure 2 and Table S1 in Supporting Information File 1). This

New highlights of the syntheses of pyrrolo[1,2-a]quinoxalin-4-ones

• Emilian Georgescu,
• Alina Nicolescu,
• Florentina Georgescu,
• Florina Teodorescu,
• Daniela Marinescu,
• Ana-Maria Macsim and
• Calin Deleanu

Beilstein J. Org. Chem. 2014, 10, 2377–2387, doi:10.3762/bjoc.10.248

• -a]quinoxalin-4-ones 4 and 10, and pyrrolo[1,2-a]benzimidazoles 5 were assigned by elemental analysis, IR and NMR spectroscopy. The 1H, 13C and 15N NMR chemical shifts have been unambiguously assigned based on the following 2D NMR experiments: H,H-COSY, H,C-HSQC, H,C-HMBC, H,N-HMBC, H,H-NOESY. In the

• nuclei (CDCl3 referenced at 77.0 ppm), and referenced to liquid ammonia (0.0 ppm) using nitromethane (380.2 ppm) as external standard for 15N nuclei. Unambiguous 1D NMR signal assignments were made based on 2D NMR homo- and heteronuclearcorrelations. H,H-COSY, H,H-NOESY, H,C-HSQC and H,C-HMBC experiments

Facile synthesis of 1H-imidazo[1,2-b]pyrazoles via a sequential one-pot synthetic approach

• András Demjén,
• Márió Gyuris,
• János Wölfling,
• László G. Puskás and
• Iván Kanizsai

Beilstein J. Org. Chem. 2014, 10, 2338–2344, doi:10.3762/bjoc.10.243

• have predominantly been described as 5H-imidazo[1,2-b]pyrazoles with an endo double bond (and not as 1H-imidazo[1,2-b]pyrazoles), but without 2D NMR-based support. However, the GBB-3CR of functionalized pyrazoles might lead to the formation of two regioisomers [24] and four different tautomeric forms

• of 59% during a reaction time of 15 min when a catalytic amount of HClO4 (20 mol %) was used as GBB-3CR promoter [7] in EtOH. 1D- and 2D NMR techniques (1H,13C-HSQC, 1H,13C-HMBC, 1H,1H-COSY and 1H,1H-NOESY) confirmed the exclusive presence of a 1H-imidazo[1,2-b]pyrazole core with an endocyclic double

Expeditive synthesis of trithiotriazine-cored glycoclusters and inhibition of Pseudomonas aeruginosa biofilm formation

• Meriem Smadhi,
• Sophie de Bentzmann,
• Anne Imberty,
• Marc Gingras,
• Raoudha Abderrahim and
• Peter G. Goekjian

Beilstein J. Org. Chem. 2014, 10, 1981–1990, doi:10.3762/bjoc.10.206

• (below). C) PAO1 growth inhibition control test. Synthesis of trivalent trithiotriazine-based glycoclusters. Synthesis of mixed triazine-based glycoclusters. Thermodynamic parameters of glycoclusters upon binding to lecA by ITCa. Supporting Information Full 1D and 2D NMR spectra of compounds 1, 2, and 9

Influence of cyclodextrin on the UCST- and LCST-behavior of poly(2-methacrylamido-caprolactam)-co-(N,N-dimethylacrylamide)

• Alexander Burkhart and
• Helmut Ritter

Beilstein J. Org. Chem. 2014, 10, 1951–1958, doi:10.3762/bjoc.10.203

• Avance DRX 300 by using dimethyl sulfoxide-d6 or chloroform-d as solvents. The chemical shifts (δ) are given in parts per million (ppm) using the solvent peak as an internal standard. 2D NMR-spectroscopy was performed using a Bruker Avance III DRX 300 at 300 MHz in D2O as a solvent. The samples were

• different amounts (Table 2). These solutions are stirred for additional 24 h before recording an 1H NMR. Turbidity curves upon heating and corresponding curves upon cooling of 10 mg ml−1 solution of polymer 6a and 6aCD at a heating/cooling rate of 1 °C min−1. 2D NMR ROESY (300 MHz, D2O) spectrum of monomer

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

• (150 W, 80 °C) facilitated the complete tetra-functionalization in only 40 minutes. Subsequent deacetylation with the Zemplén method led to target compounds 3 and 4, both of which were characterized by 1D and 2D NMR techniques and ESIMS analyses. Gal-3/glycocalixarenes interaction studies by SPR His6

C–H-Functionalization logic guides the synthesis of a carbacyclopamine analog

• Sebastian Rabe,
• Johann Moschner,
• Marina Bantzi,
• Philipp Heretsch and
• Athanassios Giannis

Beilstein J. Org. Chem. 2014, 10, 1564–1569, doi:10.3762/bjoc.10.161

• recording and interpreting the 2D NMR spectra.

Bis(β-lactosyl)-[60]fullerene as novel class of glycolipids useful for the detection and the decontamination of biological toxins of the Ricinus communis family

• Hirofumi Dohi,
• Takeru Kanazawa,
• Akihiro Saito,
• Keita Sato,
• Hirotaka Uzawa,
• Yasuo Seto and
• Yoshihiro Nishida

Beilstein J. Org. Chem. 2014, 10, 1504–1512, doi:10.3762/bjoc.10.155

• toluene/ethyl acetate, hexane/ethyl acetate, cyclohexane/ethyl acetate, and chloroform/methanol mixtures as eluents. 1H NMR (500 MHz), 13C NMR (125 MHz), and 2D NMR spectra were recorded with a JNM-LA-500s or JNM-ECA-500 spectrometer (JEOL, Japan). Unless otherwise stated, NMR spectra were recorded at 22

Efficient routes toward the synthesis of the D-rhamno-trisaccharide related to the A-band polysaccharide of Pseudomonas aeruginosa

• Aritra Chaudhury,
• Sajal K. Maity and
• Rina Ghosh

Beilstein J. Org. Chem. 2014, 10, 1488–1494, doi:10.3762/bjoc.10.153

• –13 and 2D NMR (COSY, HSQC and HMBC) of compound 10. Acknowledgements The authors are grateful to CSIR, New Delhi, India for providing a fellowship (SRF) to AC and funding of project (No. 2382/01/10/2010 EMR II) to RG. Financial assistance from DST-SERB, India to RG and supports from CAS-UGC, India

A complete series of 6-deoxy-monosubstituted tetraalkylammonium derivatives of α-, β-, and γ-cyclodextrin with 1, 2, and 3 permanent positive charges

• Martin Popr,
• Simona Hybelbauerová and
• Jindřich Jindřich

Beilstein J. Org. Chem. 2014, 10, 1390–1396, doi:10.3762/bjoc.10.142

• substituents by 2D NMR techniques. We believe that the products presented in this article will find their use as chiral selectors in CZE. They offer the possibility to choose the number of charges to tune the electrophoretic mobility. Furthermore, the diameter of the CD cavity can be modified so that the

Synthesis of zearalenone-16-β,D-glucoside and zearalenone-16-sulfate: A tale of protecting resorcylic acid lactones for regiocontrolled conjugation

• Hannes Mikula,
• Julia Weber,
• Dennis Svatunek,
• Philipp Skrinjar,
• Gerhard Adam,
• Rudolf Krska,
• Christian Hametner and
• Johannes Fröhlich

Beilstein J. Org. Chem. 2014, 10, 1129–1134, doi:10.3762/bjoc.10.112

• -dimethylimidazole, CH2Cl2, 12 h, rt, 91%, b: TBAF, AcOH, THF, 3 h, −10 °C, c: Zn, HCOONH4, MeOH, 16 h, rt, 65% (2 steps). Supporting Information Supporting Information File 132: Experimental details (including remarks and general procedures), characterization data, copies of NMR spectra of new compounds, 2D NMR

Staudinger ligation towards cyclodextrin dimers in aqueous/organic media. Synthesis, conformations and guest-encapsulation ability

• Malamatenia D. Manouilidou,
• Yannis G. Lazarou,
• Irene M. Mavridis and
• Konstantina Yannakopoulou

Beilstein J. Org. Chem. 2014, 10, 774–783, doi:10.3762/bjoc.10.73

• analytical data for the synthesis of all compounds; additional 2D NMR spectra; the computational procedure and a table of intramolecular distances for the three limiting conformations of 4 and 6 and for a pair of 4. Theoretical geometries of intermolecular dimers of 4 and of the complex 4/ada are also shown

Chromatographically separable rotamers of an unhindered amide

• Mario Geffe,
• Lars Andernach,
• Oliver Trapp and
• Till Opatz

Beilstein J. Org. Chem. 2014, 10, 701–706, doi:10.3762/bjoc.10.63

• and 2D NMR spectra of compounds 3 and 4, atom coordinates and DFT energies for ground- and transition states. Acknowledgements We thank Dr. J. C. Liermann (Mainz) for NMR spectroscopy, the Zentrum für Datenverarbeitung (Mainz) for granting access to the MOGON supercomputer as well as the

End-group-functionalized poly(N,N-diethylacrylamide) via free-radical chain transfer polymerization: Influence of sulfur oxidation and cyclodextrin on self-organization and cloud points in water

• Sebastian Reinelt,
• Daniel Steinke and
• Helmut Ritter

Beilstein J. Org. Chem. 2014, 10, 680–691, doi:10.3762/bjoc.10.61

• -CD (2 equiv) (straight blue line – heating curve; dotted blue line – cooling curve) in aqueous solution at a concentration of 10 mg/mL. 2D NMR NOESY spectrum of polymer 8b with two equivalents RAMEB-CD in D2O (600 MHz, rt). Left: Schematic illustration of the micellar-like structures and

• , characterization methods and syntheses of the obtained compounds; spectroscopic data (1H, 13C and 2D NMR); curves of the turbidity measurements, Mayo-Plot for the determination of the chain transfer constant. Supporting Information File 166: Title Experimental part.

Conformation of dehydropentapeptides containing four achiral amino acid residues – controlling the role of L-valine

• Michał Jewgiński,
• Joanna Krzciuk-Gula,
• Maciej Makowski,
• Rafał Latajka and
• Paweł Kafarski

Beilstein J. Org. Chem. 2014, 10, 660–666, doi:10.3762/bjoc.10.58

• carried out to determine the structures and the conformational preferences of the three dehydropentapeptides shown in Figure 1. NMR spectroscopy The combination of standard 1D and 2D NMR experiments, especially TOCSY, 1H,13C HSQC and 1H,13C HMBC, formed the basis of structural studies of the investigated

Visible-light photoredox catalysis enabled bromination of phenols and alkenes

• Yating Zhao,
• Zhe Li,
• Chao Yang,
• Run Lin and
• Wujiong Xia

Beilstein J. Org. Chem. 2014, 10, 622–627, doi:10.3762/bjoc.10.53

• . The stereochemistry of the bromofuran compound was determined by 2D NMR spectra. Conclusion In summary, we have developed a mild and operationally simple method for the in situ preparation of bromine utilizing a visible-light photoredox catalyst. The reaction proceeds with high chemical yield and

New sesquiterpene hydroquinones from the Caribbean sponge Aka coralliphagum

• Qun Göthel and
• Matthias Köck

Beilstein J. Org. Chem. 2014, 10, 613–621, doi:10.3762/bjoc.10.52

• 2D NMR as well as HRMS-ESI(−) experiments. The 1H and 13C NMR chemical shifts for the five new compounds are given in Table 1. Siphonodictyal E1 (1) was identified by NMR data and its accurate mass of 598.1338 [M + Na − 2H]− which indicated the molecular formula C24H35NO11S2. Comparison of the NMR

• the antiproliferation assays are given in µM. Supporting Information Supporting Information File 138: 1D and 2D NMR spectra of the isolated compounds. Acknowledgements Financial support from the Deutsche Forschungsgemeinschaft (DFG) under grants Ko 1314/5-1 and 5-2 (DFG research unit FOR 934) is

An oxidative amidation and heterocyclization approach for the synthesis of β-carbolines and dihydroeudistomin Y

• Suresh Babu Meruva,
• Akula Raghunadh,
• Raghavendra Rao Kamaraju,
• U. K. Syam Kumar and
• P. K. Dubey

Beilstein J. Org. Chem. 2014, 10, 471–480, doi:10.3762/bjoc.10.45

• -benzoyldihydrocarboline from α-ketoamide 9 [28]. The structure of 2,9-dihydro-β-carboline 7 and 1-hydroxytetrahydro-β-carboline 8 was confirmed by various NMR techniques such as 2D NMR, COSY as well as HSQC (Figure 2). The coupling of the H2 proton with both H1 and H3 protons is clearly evident in the COSY for 7a

Total synthesis and cytotoxicity of the marine natural product malevamide D and a photoreactive analog

• Werner Telle,
• Gerhard Kelter,
• Heinz-Herbert Fiebig,
• Peter G. Jones and
• Thomas Lindel

Beilstein J. Org. Chem. 2014, 10, 316–322, doi:10.3762/bjoc.10.29

• . Most of the carbon signals of the western tripeptide of malevamide D are broadened (see Supporting Information File 1). The 1H NMR spectrum shows many broad and overlapping signals, the assignment of which was only possible by careful interpretation of the 2D NMR data set. The only isolated signals

Convergent synthesis of a tetrasaccharide repeating unit of the O-specific polysaccharide from the cell wall lipopolysaccharide of Azospirillum brasilense strain Sp7

• Pintu Kumar Mandal,
• Debashis Dhara and
• Anup Kumar Misra

Beilstein J. Org. Chem. 2014, 10, 293–299, doi:10.3762/bjoc.10.26

• : 1D and 2D NMR spectra of compounds 1, 2, 7, 8, 9, 10. Acknowledgements D.D. thanks CSIR, New Delhi for providing a Junior Research Fellowship. This work was supported by CDRI, India (CDRI communication no 8596).

Tanzawaic acids I–L: Four new polyketides from Penicillium sp. IBWF104-06

• Louis P. Sandjo,
• Eckhard Thines,
• Till Opatz and
• Anja Schüffler

Beilstein J. Org. Chem. 2014, 10, 251–258, doi:10.3762/bjoc.10.20

• Magnaporthe oryzae, one of the most devastating plant diseases on cultivated rice. Bioactivity-guided fractionation of organic extracts led to the isolation of a series of eight pure compounds, the structures of which were elucidated by 2D NMR spectroscopy as well as by mass spectrometry. Results and

• these assays up to 50 µg/mL. Experimental General experimental procedures. Optical rotations were measured on a Perkin Elmer polarimeter model 241 at 546 and 578 nm and were extrapolated to 589 nm using Drude’s equation [10]. 1H, 13C and 2D NMR spectra were recorded on a Bruker AVANCE III 600 MHz

The regioselective synthesis of spirooxindolo pyrrolidines and pyrrolizidines via three-component reactions of acrylamides and aroylacrylic acids with isatins and α-amino acids

• Tatyana L. Pavlovskaya,
• Fedor G. Yaremenko,
• Victoria V. Lipson,
• Svetlana V. Shishkina,
• Oleg V. Shishkin,
• Vladimir I. Musatov and
• Alexander S. Karpenko

Beilstein J. Org. Chem. 2014, 10, 117–126, doi:10.3762/bjoc.10.8

• compounds 7a–7c (Scheme 2). The unexpected structure of rearranged product 7a was confirmed by 1H, 13C and 2D NMR spectroscopy (Table 3). The main feature of the 13C spectra of compounds 7a–7c is the absence of the signal of the 3C-spiro nucleus. The 1H NMR spectrum of compound 7a displays a singlet at 5.30

Synthesis of novel derivatives of 5-hydroxymethylcytosine and 5-formylcytosine as tools for epigenetics

• Anna Chentsova,
• Era Kapourani and
• Athanassios Giannis

Beilstein J. Org. Chem. 2014, 10, 7–11, doi:10.3762/bjoc.10.2

• diastereomers 6a–c, 7a–d, 8a–e and 9a–d. Supporting Information Supporting Information File 50: Experimental details and analytical data of all synthesized compounds. Acknowledgements We thank Dr. Lothar Hennig (Universität Leipzig) for recording NMR spectra and for his help in interpreting the 2D NMR spectra