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

• . It gave a pseudo-molecular ion of m/z 403.2090 (calcd for [C21H32O6 + Na]+, 403.2097) in its HR-ESI mass spectrum. The composition accounted for six double bond equivalents and a characteristic absorption band for α,β-unsaturated γ-lactones was revealed in the UV spectrum at 207 nm. This was

The myxocoumarins A and B from Stigmatella aurantiaca strain MYX-030

• Tobias A. M. Gulder,
• Snežana Neff,
• Traugott Schüz,
• Tammo Winkler,
• René Gees and
• Bettina Böhlendorf

Beilstein J. Org. Chem. 2013, 9, 2579–2585, doi:10.3762/bjoc.9.293

• . Comparison of UV and molecular mass data of these secondary metabolites with an in-house compound library resulted in no hits, thus prompting us to their isolation and structural elucidation. The UV spectrum of 7 revealed maxima at 218 and 286 nm, strongly suggesting the presence of an aromatic system within

Microflow photochemistry: UVC-induced [2 + 2]-photoadditions to furanone in a microcapillary reactor

• Sylvestre Bachollet,
• Kimitada Terao,
• Shin Aida,
• Yasuhiro Nishiyama,
• Kiyomi Kakiuchi and
• Michael Oelgemöller

Beilstein J. Org. Chem. 2013, 9, 2015–2021, doi:10.3762/bjoc.9.237

• ][6][7][8][9]. FEP is transparent above 230 nm and shows a good UV-stability [37]. In acetonitrile, furanone 1 gave a simple UV-spectrum with the important n→π* absorption as a shoulder between 240 to 270 nm. It thus matches well with the dominant emission of the UVC lamp at 254 nm (Figure 3a). At

• with inserted μ-capillary unit. A 10 AU-cent coin is shown for comparison. (b) μ-Capillary unit. (a) UV-spectrum of 1 (in MeCN) vs emission spectrum of the UVC lamp. (b) Light-penetration profile for a 0.1 M solution of 1 at 254 nm. The vertical lines represent the effective pathlength in the test tube

• (Ministry of Education, Culture, Sports, Science and Technology of the Japanese Government) and the Student Exchange Support Program from the Japan Student Service Organization (JASSO). The authors thank Dr. Norbert Hoffmann (University of Reims) for providing the UV-spectrum of 1.

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

• , after work-up, the diol 60 in the form of colorless cubes. The IR spectrum of the compound is dominated by an intense OH absorption band at 3220 cm−1; in the 1H NMR spectrum both the olefinic (δ 6.99 ppm) and the methyl protons (δ 1.54 ppm) appear as sharp singlets; the UV spectrum reveals the presence

Amino-substituted diazocines as pincer-type photochromic switches

• Hanno Sell,
• Christian Näther and
• Rainer Herges

Beilstein J. Org. Chem. 2013, 9, 1–7, doi:10.3762/bjoc.9.1

• retained. For determination of the ratio of isomers in photostationary states we used 1H NMR (for details see Supporting Information File 1). The UV spectrum of cis-3,3’-diamino-EBAB 4 exhibits a π–π* transition at 350 nm, and a shoulder at approximately 400 nm, which arises from the n–π* transition of the

Molecular solubilization of fullerene C₆₀ in water by γ-cyclodextrin thioethers

• Hai Ming Wang and
• Gerhard Wenz

Beilstein J. Org. Chem. 2012, 8, 1644–1651, doi:10.3762/bjoc.8.188

• with C60. Particle sizes of C60 were determined by dynamic light scattering. Keywords: C60; cyclodextrins; dynamic light scattering; particle size; solubilization; UV spectrum; Introduction Since the first spectroscopic discovery of buckminsterfullerene, C60, by Kroto, Heath, Curl and Smalley in 1985

Control over molecular motion using the cis–trans photoisomerization of the azo group

• Estíbaliz Merino and
• María Ribagorda

Beilstein J. Org. Chem. 2012, 8, 1071–1090, doi:10.3762/bjoc.8.119

• azobenzene. Representative example of an UV spectrum of an azocompound of the azobenzene type (blue line: trans isomer; magenta line: cis isomer). Mechanistic proposals for the isomerization of azobenzenes. Representation of the photocontrol of a K+ channel in the cellular membrane based on the isomerization

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

• ); solvent B, methanol) and detection at 252 and 365 nm. Additionally, a UV spectrum from 200 to 400 nm was logged by a photodiode array detector. The absorbance at 365 nm was used for quantitative analysis, employing an authentic reference sample of PCA as the external standard. Analysis by LC–MS The

Conserved and species-specific oxylipin pathways in the wound-activated chemical defense of the noninvasive red alga Gracilaria chilensis and the invasive Gracilaria vermiculophylla

• Martin Rempt,
• Florian Weinberger,
• Katharina Grosser and
• Georg Pohnert

Beilstein J. Org. Chem. 2012, 8, 283–289, doi:10.3762/bjoc.8.30

• an additional signal of an arachidonic acid derived metabolite with a characteristic UV spectrum of a conjugated tetraene. Purification yielded about 2.3 mg of an unstable metabolite, which was submitted to MS, 1D and 2D-NMR analysis. The molecular formula C20H28O2 was determined by HRMS–ESI ([M + Na

Microphotochemistry: 4,4'-Dimethoxybenzophenone mediated photodecarboxylation reactions involving phthalimides

• Oksana Shvydkiv,
• Kieran Nolan and
• Michael Oelgemöller

Beilstein J. Org. Chem. 2011, 7, 1055–1063, doi:10.3762/bjoc.7.121

• chemtech) under a UV exposure panel (Luzchem) and connected to a syringe pump. UV-spectrum of DMBP (in MeCN) versus emission spectrum of the UVA lamp. The vertical dotted line represents the cut-off wavelength of Foturan™ and Pyrex at 300 nm (approx. 30% transmission). Light-penetration profile for a 1.5

Stereogenic boron in 2-amino-1,1-diphenylethanol-based boronate–imine and amine complexes

• Sebastian Schlecht,
• Walter Frank and
• Manfred Braun

Beilstein J. Org. Chem. 2011, 7, 615–621, doi:10.3762/bjoc.7.72

• as shown in Figure 1. Although the compound crystallized as a conglomerate, the (S)-enantiomer is shown arbitrarily in Figure 1a. The boron–nitrogen distance of 156.3 pm clearly shows the existence of a coordinate bond. The UV spectrum of compound 8 displays a high-wavelength absorption maximum at λ

β-Hydroxy carbocation intermediates in solvolyses of di- and tetra-hydronaphthalene substrates

• Jaya S. Kudavalli and
• Rory A. More O'Ferrall

Beilstein J. Org. Chem. 2010, 6, 1035–1042, doi:10.3762/bjoc.6.118

• acetonitrile into 2 mL of water or aqueous acetonitrile in a cuvette and monitoring the reaction from the change in the UV spectrum. For 1-chloro-1,2,3,4-tetrahydronaphthalene rate constants (s−1) were measured for the following acetonitrile water solvent mixtures: 50% MeCN, 0.0320; 60% MeCN, 0.0106; 70% MeCN

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

• UV spectrum (Figure 8e); the intensity of the band increased with increasing temperature (Figure 8a). As reported for the self-assembled alanine based gelators, the CD signal at around 232 nm can be ascribed to the n,π*-transition of the amide carbonyl [72][73][74]. Hence, the λ = 234 nm band that

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

• determination of the helicity. Even the Cotton effects at around 350 nm are of the same sign in both spectra. However, the calculations overestimate the intensity of this excitation; this overestimation can also be found in the calculated UV spectrum. Moreover, in both spectra the excitations at higher

• wavelengths exhibit a positive Cotton effect. As the calculated maximum of the UV spectrum (530 nm) shows a bathochromic shift relative to the measured UV spectrum (470 nm), the corresponding peak in the calculated CD spectrum (540 nm) is shifted to higher wavelengths relative to the experimentally measured

Reversible intramolecular photocycloaddition of a bis(9-anthrylbutadienyl)paracyclophane – an inverse photochromic system. (Photoactive cyclophanes 5)

• Henning Hopf,
• Christian Beck,
• Jean-Pierre Desvergne,
• Henri Bouas-Laurent,
• Peter G. Jones and
• Ludger Ernst

Beilstein J. Org. Chem. 2009, 5, No. 20, doi:10.3762/bjoc.5.20

• for the structure rests on the electronic absorption spectrum and the NMR spectral data. The UV spectrum clearly shows the disappearance of the 350–450 nm absorption band, indicating that the anthryl groups have reacted. The new band with a maximum at 306 nm suggests the formation of substituted

Synthesis of 2,3,6,7-tetrabromoanthracene

• Christian Schäfer,
• Friederike Herrmann and
• Jochen Mattay

Beilstein J. Org. Chem. 2008, 4, No. 41, doi:10.3762/bjoc.4.41

• (1.04 mmol, 58%), Rf 0.79 (dichloromethane); Rf 0.27 (cyclohexane); mp >220 °C (decomposition); 1H NMR (CDCl3): δ [ppm] = 8.20 (s, 2 H, ArH), 8.30 (s, 4 H, ArH); 13C NMR (CDCl3): δ [ppm] = 122.8 (CAr,q), 124.8 (CArH), 131.2 (CAr,q), 132.2 (CArH); UV spectrum: λmax(cyclohexane)/nm (ε/dm3 mol−1 cm−1) 395