Homochiral BINOL-based macrocycles with π-electron-rich, electron-withdrawing or extended spacing units as receptors for C₆₀

• Marco Caricato,
• Silvia Díez González,
• Idoia Arandia Ariño and
• Dario Pasini

Beilstein J. Org. Chem. 2014, 10, 1308–1316, doi:10.3762/bjoc.10.132

• chemical shifts for compounds in CDCl3 (25 °C).a Thermodynamic binding constants of the complexation of C60 with macrocycles 4 in toluene (25 °C).a Supporting Information Supporting Information File 158: UV spectra for selected macrocycles, additional NMR and MS spectra for all newly synthesized

cis–trans Isomerization of silybins A and B

• Michaela Novotná,
• Radek Gažák,
• David Biedermann,
• Florent Di Meo,
• Petr Marhol,
• Marek Kuzma,
• Lucie Bednárová,
• Kateřina Fuksová,
• Patrick Trouillas and
• Vladimír Křen

Beilstein J. Org. Chem. 2014, 10, 1047–1063, doi:10.3762/bjoc.10.105

• novel compounds with UV spectra similar to that of silybin. Enzymatic alcoholysis (n-butanol) of this mixture by Novozym 435 led, after a prolonged reaction time, to the removal of the acetyl groups from trans-isomers 2a and 2b to give 1a and 1b (Figure 1), while the two minor isomers remained

Theoretical studies on the intramolecular cyclization of 2,4,6-t-Bu₃C₆H₂P=C: and effects of conjugation between the P=C and aromatic moieties

• Masaaki Yoshifuji and
• Shigekazu Ito

Beilstein J. Org. Chem. 2014, 10, 1032–1036, doi:10.3762/bjoc.10.103

• –H insertion of phosphanylidenecarbene. Supporting Information Supporting Information File 99: UV Spectra for 2 and Mes*P=C(H)Me and MO for 2 and Mes*P=CH2. Supporting Information File 100: Calculation data for 1, TS, 2, Mes*P=CH2 and [MeP=C:]. Acknowledgements One of the authors (MY) thanks Prof

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

• spectrometer equipped with a cryo platform and a Bruker Avance 400 MHz NMR spectrometer. All experiments were measured at 303 K. HPLC separation was achieved by a Kromasil RP-18 column (16 mm × 250 mm, 5 µm) applying a H2O (5 mM NH4OAc)/MeCN/MeOH gradient. UV spectra were recorded during HPLC separation with a

Decandrinin, an unprecedented C₉-spiro-fused 7,8-seco-ent-abietane from the Godavari mangrove Ceriops decandra

• Hui Wang,
• Min-Yi Li,
• Félix Zongwe Katele,
• Tirumani Satyanandamurty,
• Jun Wu and
• Gerhard Bringmann

Beilstein J. Org. Chem. 2014, 10, 276–281, doi:10.3762/bjoc.10.23

• double bond of int B could yield int C. Finally, the lactonization of int C would give decandrinin (1) (Scheme 1). Experimental General methods Optical rotation values were recorded on a JASCO P-1020 polarimeter. CD spectra were recorded on a J-715 spectropolarimeter (JASCO, Gross-Umstadt, Germany). UV

• spectra were obtained on a Beckman DU-640 UV spectrophotometer. NMR spectra were recorded on a Bruker Avance 400 NMR spectrometer in CDCl3. High-resolution ESI mass spectra were performed on a Bruker maXis UHR-TOF mass spectrometer in positive ion mode. For column chromatography, silica gel (200–300 mesh

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

• with a LockSpray-interface. A Bruker IFS48 FTIR spectrometer and a Perkin-Elmer Lambda-16 spectrophotometer were used to measure the IR and UV spectra, respectively. Producing organism. The producing fungus IBWF104-06 was isolated from a soil sample. The strain was determined as a Penicillium species

SF002-96-1, a new drimane sesquiterpene lactone from an Aspergillus species, inhibits survivin expression

• Silke Felix,
• Louis P. Sandjo,
• Till Opatz and
• Gerhard Erkel

Beilstein J. Org. Chem. 2013, 9, 2866–2876, doi:10.3762/bjoc.9.323

• were measured from a solution of the analyte in acetonitrile with a Waters Q-TOF-Ultima 3 equipped with a LockSpray interface (tri-n-octylamine as external reference). IR and UV spectra were measured with a Bruker IFS48 FTIR spectrometer and a Perkin-Elmer Lambda-16 spectrophotometer, respectively. The

Less reactive dipoles of diazodicarbonyl compounds in reaction with cycloaliphatic thioketones – First evidence for the 1,3-oxathiole–thiocarbonyl ylide interconversion

• Valerij A. Nikolaev,
• Alexey V. Ivanov,
• Ludmila L. Rodina and
• Grzegorz Mlostoń

Beilstein J. Org. Chem. 2013, 9, 2751–2761, doi:10.3762/bjoc.9.309

• spectra were registered by using Perkin-Elmer "Spectrum BXII" instrument as KBr pellets. UV spectra were obtained by using a Shimadzu UV-1800 instrument in EtOH solution. Mass spectra were determined by electrospray ionization with a Bruker micrOTOF spectrometer. Quantitative analysis of the reaction

Towards a biocompatible artificial lung: Covalent functionalization of poly(4-methylpent-1-ene) (TPX) with cRGD pentapeptide

• Lena Möller,
• Christian Hess,
• Jiří Paleček,
• Yi Su,
• Axel Haverich,
• Andreas Kirschning and
• Gerald Dräger

Beilstein J. Org. Chem. 2013, 9, 270–277, doi:10.3762/bjoc.9.33

• ) F 1s core level, (c) N 1s core level. UV spectra of TPX 8c and 8d functionalized with fluorescein revealing the efficiency of the 1,3-dipolar cycloaddition reactions on modified TPX membranes. Continuous line: 8d; dotted line: 8c; dashed line: substrate for Huisgen-type “click” reaction 7a. Cell

The β-cyclodextrin/benzene complex and its hydrogen bonds – a theoretical study using molecular dynamics, quantum mechanics and COSMO-RS

• Jutta Erika Helga Köhler and
• Nicole Grczelschak-Mick

Beilstein J. Org. Chem. 2013, 9, 118–134, doi:10.3762/bjoc.9.15

• in good qualitatively agreement with the complex formation constants that were experimentally determined from UV spectra in [34] and showed that the complex was more stable at lower temperatures. At 300 K benzene tried to leave the cavity early at the O6 side, but always returned. It spent most of

Polar reactions of acyclic conjugated bisallenes

• Reiner Stamm and
• Henning Hopf

Beilstein J. Org. Chem. 2013, 9, 36–48, doi:10.3762/bjoc.9.5

• could be separated (under considerable material loss) by preparative gas chromatography, and according to their spectral data (see Supporting Information File 1), we assign structures 55 and 56 to them (Scheme 11). As in the case of the HCl addition to 2, the UV spectra of the products were particularly

Bioactive selaginellins from Selaginella tamariscina (Beauv.) Spring

• Chao Yang,
• Yutian Shao,
• Kang Li and
• Wujiong Xia

Beilstein J. Org. Chem. 2012, 8, 1884–1889, doi:10.3762/bjoc.8.217

• Elmer Spectrum 100 FT-IR Spectrometer. All NMR spectra data were recorded on a Bruker 400 MHz AVANCE III FT-NMR spectrometer operating at 400 MHz for 1H and 100 MHz for 13C NMR by using TMS as the internal standard. HRMS–ESI spectrum was obtained on an Agilent 1200-6520 QTOF. UV spectra were recorded on

Design of a novel tryptophan-rich membrane-active antimicrobial peptide from the membrane-proximal region of the HIV glycoprotein, gp41

• Evan F. Haney,
• Leonard T. Nguyen,
• David J. Schibli and
• Hans J. Vogel

Beilstein J. Org. Chem. 2012, 8, 1172–1184, doi:10.3762/bjoc.8.130

• previous scan, indicating that equilibrium had been reached. Circular dichroism spectroscopy CD spectra were collected at room temperature on a Jasco J815 spectropolarimeter by using a 0.1 cm path length cuvette. Far-UV spectra of 50 μM peptide solutions were collected between 190–260 nm with a 0.5 nm step

Synthesis and structure of tricarbonyl(η⁶-arene)chromium complexes of phenyl and benzyl D-glycopyranosides

• Thomas Ziegler and
• Ulrich Heber

Beilstein J. Org. Chem. 2012, 8, 1059–1070, doi:10.3762/bjoc.8.118

• IR spectrometer. UV spectra were recorded with a Shimadzu UV 2102 PC spectrometer. Elemental analyses were performed on a Hekatech Euro 3000 CHN analyzer. Optical rotations were measured with a Perkin-Elmer Polarimeter 341. Melting points were determined with a Büchi B-540 apparatus and are

Mutational analysis of a phenazine biosynthetic gene cluster in Streptomyces anulatus 9663

• Orwah Saleh,
• Katrin Flinspach,
• Lucia Westrich,
• Andreas Kulik,
• Bertolt Gust,
• Hans-Peter Fiedler and
• Lutz Heide

Beilstein J. Org. Chem. 2012, 8, 501–513, doi:10.3762/bjoc.8.57

• M512(ppzOS04) after five days of cultivation. The oxygen carrier Q2-5247 was not included in the culture medium in this experiment. Detection wavelength: 365 nm. The lower panels show the UV spectra of endophenazine A and endophenazine E. Extracted ion chromatograms for the mass of endophenazine B (m/z

Carbamate derivatives and sesquiterpenoids from the South China Sea gorgonian Melitodes squamata

• Li-Si Huang,
• Fei He,
• Hui Huang,
• Xiao-Yong Zhang and
• Shu-Hua Qi

Beilstein J. Org. Chem. 2012, 8, 170–176, doi:10.3762/bjoc.8.18

• quantity of compound, we did not further test the other bioactivities of 6 and 7. Experimental General experimental procedures Optical rotations were measured with a Horiba SEAP-300 spectropolarimeter. UV spectra were measured with a Shimadzu double-beam 210A spectrophotometer in MeOH solution. 1H, 13C NMR

Equilibrium constants and protonation site for N-methylbenzenesulfonamides

• José A. Moreira,
• Ana M. Rosa da Costa,
• Luis García-Río and
• Márcia Pessêgo

Beilstein J. Org. Chem. 2011, 7, 1732–1738, doi:10.3762/bjoc.7.203

• to stand in a water bath at 20 °C and the final volume in the volumetric flask was adjusted. Spectroscopic measurements Solutions of 3a–d (5.0 × 10−5 M) were prepared by adding a small amount, typically 30 µL, of a stock solution to 10 mL of the sulfuric acid solution. UV spectra were recorded in a

Ratiometric fluorescent probe for enantioselective detection of D-cysteine in aqueous solution

• Xiao-bo Zhou,
• Wing-Hong Chan,
• Albert W. M. Lee and
• Chi-Chung Yeung

Beilstein J. Org. Chem. 2011, 7, 1508–1515, doi:10.3762/bjoc.7.176

• -Glu; D-Lys; L-Lys; D-Ser; L-Ser; D-Tyr; L-Tyr; D-Val; L-Val; D-Phe; L-Phe; D-His; L-His. UV spectra of Cd2+–ACAQ (25 µm) upon the titration of (a) D-Cys, (b) L-Cys (0–12 equiv) in buffer solution (10 mM , HEPES, 50% ACN, pH 7.4 ) at 298 K. The inset shows the titration data points and the nonlinear

Novel carbazole–pyridine copolymers by an economical method: synthesis, spectroscopic and thermochemical studies

• Aamer Saeed,
• Madiha Irfan and
• Shahid Ameen Samra

Beilstein J. Org. Chem. 2011, 7, 638–647, doi:10.3762/bjoc.7.75

• . The weight average molecular masses (Mw) of the polymers were estimated by the laser light scattering (LLS) technique. Keywords: carbazole–pyridine copolymers; fluorescent materials; organic light emitting diode (OLED); photoluminescence spectra; UV spectra; Introduction An immense research effort

Photoinduced electron-transfer chemistry of the bielectrophoric N-phthaloyl derivatives of the amino acids tyrosine, histidine and tryptophan

• Axel G. Griesbeck,
• Jörg Neudörfl and
• Alan de Kiff

Beilstein J. Org. Chem. 2011, 7, 518–524, doi:10.3762/bjoc.7.60

• decarboxylation product, the N-phthaloyl tryptamine (14). Compound 10 represents a donor–ethylene bridge–acceptor situation and intramolecular electron transition (ET) is feasible. The UV spectra of the three substrates 8–10 (Figure 3) showed in fact two major absorption peaks for 8 and 10 at 280 and 300 nm

Light-induced olefin metathesis

• Yuval Vidavsky and
• N. Gabriel Lemcoff

Beilstein J. Org. Chem. 2010, 6, 1106–1119, doi:10.3762/bjoc.6.127

• reactions was not explained, even though it is slightly counterintuitive. In order to improve the understanding of the photoactivation mechanism, complex 16g was irradiated by visible light both in the presence and absence of cyclooctene. NMR and UV spectra confirmed the release of p-cymene from the complex

Oxalyl retro-peptide gelators. Synthesis, gelation properties and stereochemical effects

• Janja Makarević,
• Milan Jokić,
• Leo Frkanec,
• Vesna Čaplar,
• Nataša Šijaković Vujičić and
• Mladen Žinić

Beilstein J. Org. Chem. 2010, 6, 945–959, doi:10.3762/bjoc.6.106

• 1-butanol gel (c = 2.8·10−2 M); e), f) UV spectra of (S,R)-1b (red curve), (R,S)-1b and (S,S)-1b taken in decalin at specified concentrations. X-ray powder diffractograms of (a) (S,R)-1b and (b) (S,S)-1b xerogels prepared from their toluene gels. (a) Fully minimized the lowest energy conformations

A perfluorocyclopentene based diarylethene bearing two terpyridine moieties – synthesis, photochemical properties and influence of transition metal ions

• Falk Wehmeier and
• Jochen Mattay

Beilstein J. Org. Chem. 2010, 6, No. 53, doi:10.3762/bjoc.6.53

• synthesized according to previously reported procedures. Solvents and chemicals were dried by standard methods. Irradiation experiments were carried out in a quartz cuvette (d = 1 cm) and the solutions were not degassed before irradiation. UV-spectra were recorded with a Lambda 40 (Perkin-Elmer) at room

Self-association of an indole based guanidinium-carboxylate-zwitterion: formation of stable dimers in solution and the solid state

• Carolin Rether,
• Wilhelm Sicking,
• Roland Boese and
• Carsten Schmuck

Beilstein J. Org. Chem. 2010, 6, No. 3, doi:10.3762/bjoc.6.3

• the Attenuated Total Reflectance (ATR). Melting points are not corrected. The pH values were measured with a Knick pH meter 766 Calimatic at 25 °C. UV spectra were measured in 10 mm rectangular cells with a Jasco V660 spectrometer. Ethyl 7-amino-1H-indole-2-carboxylate (4): A mixture of ethyl 7-nitro

An enantiomerically pure siderophore type ligand for the diastereoselective 1 : 1 complexation of lanthanide(III) ions

• Markus Albrecht,
• Olga Osetska,
• Thomas Abel,
• Gebhard Haberhauer and
• Eva Ziegler

Beilstein J. Org. Chem. 2009, 5, No. 78, doi:10.3762/bjoc.5.78

• reliable behaviour (Figure 5). The spectra for the two different metal ions are very similar indicating that the observed transitions are ligand-centered. CD as well as UV spectra of the titration of 1a-H3 with lanthanum(III) are shown in Figure 4, while Figure 5 depicts the corresponding titration curve