Archangelolide: A sesquiterpene lactone with immunobiological potential from Laserpitium archangelica

• Silvie Rimpelová,
• Michal Jurášek,
• Lucie Peterková,
• Jiří Bejček,
• Vojtěch Spiwok,
• Miloš Majdl,
• Michal Jirásko,
• Miloš Buděšínský,
• Juraj Harmatha,
• Eva Kmoníčková,
• Pavel Drašar and
• Tomáš Ruml

Beilstein J. Org. Chem. 2019, 15, 1933–1944, doi:10.3762/bjoc.15.189

• , efficient isolation must first be performed in order to gain sufficient amount of pure SLs. Even though the presence of several immuno-active SLs, including compound 1 and 2, was previously reported in Laser trilobum (L.) Borkh and the method of their isolation from petroleum ether extracts of plant roots

Efficient resolution of racemic crown-shaped cyclotriveratrylene derivatives and isolation and characterization of the intermediate saddle isomer

• Sven Götz,
• Andreas Schneider and
• Arne Lützen

Beilstein J. Org. Chem. 2019, 15, 1339–1346, doi:10.3762/bjoc.15.133

• are Xe inclusion complexes that are of special interest as they help to establish laser-polarized 129Xe NMR spectroscopy for the imaging in biological systems [22][23][24][25]. For the formation of Xe cryptophane complexes, cryptophane-1.1.1 has proven to be a very suitable host as it still shows the

Bambusuril analogs based on alternating glycoluril and xylylene units

• Tomáš Lízal and
• Vladimír Šindelář

Beilstein J. Org. Chem. 2019, 15, 1268–1274, doi:10.3762/bjoc.15.124

• ESI/APCI as an ion source and a manual pump for sampling. Matrix-assisted laser desorption ionization–time-of-flight mass spectra (MALDI–TOF MS) were measured on a MALDI–TOF MS UltrafleXtreme (Bruker Daltonics) and samples were ionized with the aid of a Nd:YAG laser (355 nm) from α-cyano-4

Precious metal-free molecular machines for solar thermal energy storage

• Meglena I. Kandinska,
• Snejana M. Kitova,
• Vladimira S. Videva,
• Stanimir S. Stoyanov,
• Stanislava B. Yordanova,
• Stanislav B. Baluschev,
• Silvia E. Angelova and
• Aleksey A. Vasilev

Beilstein J. Org. Chem. 2019, 15, 1096–1106, doi:10.3762/bjoc.15.106

• solution concentrations were chosen to give an absorbance ≤0.05 at the excitation wavelength of 440 and 488 nm. The photoisomerization of the dyes and their complexes was performed by irradiating the samples in quartz cells (1 cm) with 16 mW laser (Qioptiq iFLEX2000-P-2-488) at λ = 488 nm for 3 min, a time

• fluorescent measurements was used allowing recording of the absorbance spectra during the laser irradiation in the perpendicular direction and immediately after the stop of irradiation. Computational details Equilibrium geometries and intermolecular interaction energies for the host–guest assemblies between

Photochemical generation of the 2,2,6,6-tetramethylpiperidine-1-oxyl (TEMPO) radical from caged nitroxides by near-infrared two-photon irradiation and its cytocidal effect on lung cancer cells

• Ayato Yamada,
• Manabu Abe,
• Yoshinobu Nishimura,
• Shoji Ishizaka,
• Masashi Namba,
• Taku Nakashima,
• Kiyofumi Shimoji and
• Noboru Hattori

Beilstein J. Org. Chem. 2019, 15, 863–873, doi:10.3762/bjoc.15.84

• (Figure 2c,e). The TP photolysis of 2a (10 mM) and 2b (10 mM) was carried out in benzene under atmospheric conditions using 710, 720, 730, 740, 750, and 760 nm near infrared light from a Ti:sapphire laser (pulse width 100 fs, 80 MHz) emitting at an average of 700 mW (Figure 3 for 2a and Supporting

Low-budget 3D-printed equipment for continuous flow reactions

• Jochen M. Neumaier,
• Amiera Madani,
• Thomas Klein and
• Thomas Ziegler

Beilstein J. Org. Chem. 2019, 15, 558–566, doi:10.3762/bjoc.15.50

• ], selective laser sintering (SLS) [15], or stereolithography (SLA) [16][17]. Each method however, has advantages and disadvantages [18]. While the printing with SLA and SLS allows a very high resolution, the used photopolymer materials in stereolithography printing are poorly resistant against standard

Fabrication of supramolecular cyclodextrin–fullerene nonwovens by electrospinning

• Hiroaki Yoshida,
• Ken Kikuta and
• Toshiyuki Kida

Beilstein J. Org. Chem. 2019, 15, 89–95, doi:10.3762/bjoc.15.10

• ). Because the red photoluminescence of C60 is useful for a bioimaging applications [30][31], the electrospun fibers were measured with confocal laser scanning microscopy (CLSM). Interestingly, a uniform red color distribution is observed (Figure S9, in Supporting Information File 1), indicating the presence

Degenerative xanthate transfer to olefins under visible-light photocatalysis

• Atsushi Kaga,
• Xiangyang Wu,
• Joel Yi Jie Lim,
• Hirohito Hayashi,
• Yunpeng Lu,
• Edwin K. L. Yeow and
• Shunsuke Chiba

Beilstein J. Org. Chem. 2018, 14, 3047–3058, doi:10.3762/bjoc.14.283

• excited triplet state of 1a formed by direct 355 nm laser light excitation and triplet–triplet energy transfer involving the excited photocatalyst 8. To confirm the possibility of a direct photoexcitation of xanthate 1 using blue LED light irradiation as an alternative mechanism, a steady-state UV–vis

Organometallic vs organic photoredox catalysts for photocuring reactions in the visible region

• Aude-Héloise Bonardi,
• Frédéric Dumur,
• Guillaume Noirbent,
• Jacques Lalevée and
• Didier Gigmes

Beilstein J. Org. Chem. 2018, 14, 3025–3046, doi:10.3762/bjoc.14.282

• observed after a strong absorption of the complex centered at 380 nm (Table 4). Thus, it can react through a redox cycle with similar reaction than the Ru-based complexes under irradiation by different visible light such as a halogen lamp, laser diodes (405 and 457 nm) or LEDs (405 and 455 nm) [63]. Iron

Copolymerization of epoxides with cyclic anhydrides catalyzed by dinuclear cobalt complexes

• Yo Hiranoi and
• Koji Nakano

Beilstein J. Org. Chem. 2018, 14, 2779–2788, doi:10.3762/bjoc.14.255

• initiated by monofunctional pentafluorobenzoate from (R,R,S,S)-1 and [PPN][OCOC6F5] [19]. The formation of the alternating copolymers initiated by monofunctional pentafluorobenzoate and the bifunctional chain-transfer agents was confirmed by matrix-assisted laser desorption/ionization time-of-flight mass

Novel solid-phase strategy for the synthesis of ligand-targeted fluorescent-labelled chelating peptide conjugates as a theranostic tool for cancer

• Sagnik Sengupta,
• Mena Asha Krishnan,
• Premansh Dudhe,
• Ramesh B. Reddy,
• Bishnubasu Giri,
• Sudeshna Chattopadhyay and
• Venkatesh Chelvam

Beilstein J. Org. Chem. 2018, 14, 2665–2679, doi:10.3762/bjoc.14.244

• bioconjugates a potential theranostic tool for cancer. The newly synthesized bioconjugates 13 and 17, that can selectively target PSMA+ and FR+ cancers, were further evaluated by performing in vitro studies using laser scanning confocal microscopy on PSMA+ LNCaP cells, FR+ epithelial CHO-β cells and PSMA−, FR

• folate receptors. The in vitro uptake study has been performed using laser scanning confocal microscopy and the bioconjugates are found to be delivered specifically to cells expressing corresponding cell surface proteins. The small molecule targeted imaging probes prepared in this study are designed for

• °C. Procedure for uptake study of peptide conjugates 13 and 17 using laser scanning confocal microscope in human cancer cell lines LNCaP, PC-3 and epithelial cell line CHO-β: LNCaP cells (15,000 cells/well in 1 mL), CHO-β (10,000 cells/well in 1 mL) and PC-3 (10,000 cells/well) were seeded into

Synthesis of aryl sulfides via radical–radical cross coupling of electron-rich arenes using visible light photoredox catalysis

• Amrita Das,
• Mitasree Maity,
• Simon Malcherek,
• Burkhard König and
• Julia Rehbein

Beilstein J. Org. Chem. 2018, 14, 2520–2528, doi:10.3762/bjoc.14.228

• (1,3,5-TMB•+) is formed indeed during the quenching process of the catalyst by 1,3,5-TMB (Scheme 5) ns-time-resolved transient absorption spectroscopy was used [50]. To allow for a decomposition of the multicomponent spectra we conducted laser flash photolysis (LFP) experiments on the single components

• , indicating that probably a fragmentation of the disulfide bond took place due to the laser irradiation. Since this effect occurred also under reduced laser power (70% of the original 58 mJ/pulse) we restricted the current analysis to the two-component solution (A). Since 1,3,5-TMB did not show any transient

• : UV–vis spectrum of the degassed [Ir] + 1,3,5-TMB mixture (solution A) in ACN. Blue and red lines: Absorption spectra averaged over 10–30 ns after 355 nm laser-pulse with red being derived from the [Ir] solution I and representing the emission spectrum of the catalyst. Whereas, the blue line was

Dynamic light scattering studies of the effects of salts on the diffusivity of cationic and anionic cavitands

• Anthony Wishard and
• Bruce C. Gibb

Beilstein J. Org. Chem. 2018, 14, 2212–2219, doi:10.3762/bjoc.14.195

• software (Mestrelab Research, S.L.). All dynamic light scattering measurements were performed on a Nicomp ZLS Z3000 particle size analyzer (Particle Sizing Systems – Port Richey, FL), with a 50 mW laser diode (660 nm wavelength) and an avalanche photodiode (APD) detector. Measurements of scattered light

Synergistic electrodeposition of bilayer films and analysis by Raman spectroscopy

• Saadeldin E. T. Elmasly,
• Luca Guerrini,
• Joseph Cameron,
• Alexander L. Kanibolotsky,
• Neil J. Findlay,
• Karen Faulds and
• Peter J. Skabara

Beilstein J. Org. Chem. 2018, 14, 2186–2189, doi:10.3762/bjoc.14.191

• attributed to the PEDOT system, such as bands at 576 and 991 cm−1, can be recognised in the bilayer spectrum. The appearance of signals arising from the underlying PEDOT layer, although distant from the focal point of the laser, is likely the result of a partial de-doping of the underlying PEDOT layer. Thus

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

• gave molecular ion peaks with expulsion of two (in the case of 4) or four (in the case of 8) N2 fragments due to the lability of the azide group upon laser desorption [39]. The spatial structure of the product 8a was established by X-ray crystallography and is presented in Figure 1 including the atomic

• or DMSO-d6) as internal standard. MALDI mass spectra were measured on an UltraFlex III TOF/TOF with PNA matrix, laser Nd:YAG, λ = 355 nm. The IR spectra were recorded on a Bruker Vector-22 spectrometer. Samples were prepared as suspension in mineral oil or as thin films, obtained from chloroform

• scattering (DLS) measurements Dynamic light scattering (DLS) experiments and zeta-potential measurements (ELS) were carried out on a Zetasizer Nano ZS instrument (Malvern Instruments, USA) with 4 mW 633 nm He–Ne laser light source and a light scattering angle of 173°. The data were treated with DTS software

Rational design of boron-dipyrromethene (BODIPY) reporter dyes for cucurbit[7]uril

• Mohammad A. Alnajjar,
• Jürgen Bartelmeß,
• Robert Hein,
• Pichandi Ashokkumar,
• Mohamed Nilam,
• Werner M. Nau,
• Knut Rurack and
• Andreas Hennig

Beilstein J. Org. Chem. 2018, 14, 1961–1971, doi:10.3762/bjoc.14.171

• macrocyclic hosts and dyes that have so far been reported [16] are only of limited use for these currently emerging life science applications of CBs. Many of the fluorescent dyes which bind to CBs with significant fluorescence changes have a limited photostability, in particular under intense laser light

• illumination in confocal laser scanning microscopy [23][25], or absorb at shorter wavelengths, where biological samples show a high background from autofluorescence [26][27]. An ideal fluorescent dye would be highly photostable in biological media, have long-wavelength absorption to minimize background

• BODIPYs introduced herein matches the emission wavelength of an Ar laser, which is still the most common excitation source in fluorescence correlation spectroscopy (FCS) and fluorescence microscopy. FCS has been established to study dynamic processes in biological systems and, more recently, also in

Defining the hydrophobic interactions that drive competence stimulating peptide (CSP)-ComD binding in Streptococcus pneumoniae

• Bimal Koirala,
• Robert A. Hillman,
• Erin K. Tiwold,
• Michael A. Bertucci and
• Yftah Tal-Gan

Beilstein J. Org. Chem. 2018, 14, 1769–1777, doi:10.3762/bjoc.14.151

• liquid chromatography (RP-HPLC) was performed using two Shimadzu systems each equipped with a CBM-20A communications bus module, two LC-20AT pumps, an SIL-20A auto sampler, an SPD-20A UV–vis detector, a CTO-20A column oven, one with an FRC-10A fraction collector and one without. Matrix-assisted laser

• desorption ionization time-of-flight mass spectrometry (MALDI–TOF MS) data were obtained on either a Bruker Autoflex or Bruker Microflex spectrometer equipped with a 60 Hz nitrogen laser and a reflectron. In positive ion mode, the acceleration voltage on Ion Source 1 was 19.01 kV. Exact mass (EM) data were

Synthesis and photophysical studies of a multivalent photoreactive Ru^II-calix[4]arene complex bearing RGD-containing cyclopentapeptides

• Sofia Kajouj,
• Lionel Marcelis,
• Alice Mattiuzzi,
• Adrien Grassin,
• Damien Dufour,
• Pierre Van Antwerpen,
• Didier Boturyn,
• Eric Defrancq,
• Mathieu Surin,
• Julien De Winter,
• Pascal Gerbaux,
• Ivan Jabin and
• Cécile Moucheron

Beilstein J. Org. Chem. 2018, 14, 1758–1768, doi:10.3762/bjoc.14.150

• ; source temperature, 150 °C and desolvation temperature, 200 °C. Matrix-assisted laser desorption/ionization time-of-flight (MALDI-ToF) mass spectra were recorded using a Waters QToF Premier mass spectrometer equipped with a Nd-YAG laser of 355 nm with a maximum pulse energy of 65 μJ delivered to the

• -SPC) technique with the Edinburgh Instruments LifeSpecII Picosecond Fluorescence Lifetime Spectrometer equipped with a laser diode (λ = 439 nm, pulse = 100 ps). The samples were thermostatted at 20 ± 2 °C with a Haake Model NB22 temperature controller. The data were collected by a multichannel

• 500 ns after the laser pulse (gray, top) and 1 µs after the laser pulse in the presence of 10 mM GMP (purple, bottom). MALDI–MS analysis of a solution containing conjugate 9 and GMP after continuous light irradiation. In the inset, the experimental (bottom) and theoretical (top) isotope distributions

The phenyl vinyl ether–methanol complex: a model system for quantum chemistry benchmarking

• Dominic Bernhard,
• Fabian Dietrich,
• Mariyam Fatima,
• Cristóbal Pérez,
• Hannes C. Gottschalk,
• Axel Wuttke,
• Ricardo A. Mata,
• Martin A. Suhm,
• Melanie Schnell and
• Markus Gerhards

Beilstein J. Org. Chem. 2018, 14, 1642–1654, doi:10.3762/bjoc.14.140

• °C, respectively) and co-expanded with the carrier gas neon (2.5–3.0 bar). For the one- and two-color R2PI, the IR/R2PI and the UV/IR/UV experiments up to three tunable nanosecond laser systems were necessary, including two independent UV laser systems and one IR laser system. The UV laser radiation

• is obtained via second harmonic generation in a BBO crystal using the output of a dye laser (Cobra-Stretch and PrecisionScan, Sirah). They are pumped by the second harmonic (532 nm) of a Nd:YAG laser (SpitLight 600 and SpitLight 1000, Innolas). The IR laser radiation in the range of 3520–3750 cm−1 is

• generated by difference frequency mixing (DFM) in a LiNbO3 crystal using the fundamental (1064 nm) of a seeded Nd:YAG laser (Quanta-Ray Pro-230, Spectra-Physics) and the output of a further dye laser (PrecisionScan, Sirah), which is pumped by the second harmonic (532 nm) of the same Nd:YAG laser

Design and biological characterization of novel cell-penetrating peptides preferentially targeting cell nuclei and subnuclear regions

• Anja Gronewold,
• Mareike Horn and
• Ines Neundorf

Beilstein J. Org. Chem. 2018, 14, 1378–1388, doi:10.3762/bjoc.14.116

• viability values in %. Experiments were done in triplicate. Microscopy For microscopic analyses, a confocal laser scanning system (Nikon D-Eclipse C1) with an inverted microscope (Nikon Eclipse Ti) was used. Pictures were taken with a 60× oil immersion objective (N.A. 1.4, Plan APO VC; Nikon) using the

One hundred years of benzotropone chemistry

• Arif Dastan,
• Haydar Kilic and
• Nurullah Saracoglu

Beilstein J. Org. Chem. 2018, 14, 1120–1180, doi:10.3762/bjoc.14.98

Synthesis and in vitro biochemical evaluation of oxime bond-linked daunorubicin–GnRH-III conjugates developed for targeted drug delivery

• Sabine Schuster,
• Beáta Biri-Kovács,
• Bálint Szeder,
• Viktor Farkas,
• László Buday,
• Zsuzsanna Szabó,
• Gábor Halmos and
• Gábor Mező

Beilstein J. Org. Chem. 2018, 14, 756–771, doi:10.3762/bjoc.14.64

• reported on the identification of a novel daunorubicin–GnRH-III conjugate (GnRH-III–[4Lys(Bu), 8Lys(Dau=Aoa)] with efficient in vitro and in vivo antitumor activity. To get a deeper insight into the mechanism of action of our lead compound, the cellular uptake was followed by confocal laser scanning

• linked to the DNA by formation of a tyrosine phosphodiester [10][11][12]. Moreover, anthracyclines provide a beneficial auto-fluorescence allowing the performance of fluorescence based studies like confocal laser scanning microscopy (CLSM) and fluorescence-activated cell sorting (FACS) to investigate the

• or even higher than the IC50 value of the other compounds 2, 4 and 5. It can be assumed that this effect occurred due to the reduced release of the smallest Dau-containing metabolite. Confocal laser scanning microscopy (CLSM) studies Next to the quantitative analysis of the cellular uptake by flow

Heterogeneous Pd catalysts as emulsifiers in Pickering emulsions for integrated multistep synthesis in flow chemistry

• Katharina Hiebler,
• Georg J. Lichtenegger,
• Manuel C. Maier,
• Eun Sung Park,
• Renie Gonzales-Groom,
• Bernard P. Binks and
• Heidrun Gruber-Woelfler

Beilstein J. Org. Chem. 2018, 14, 648–658, doi:10.3762/bjoc.14.52

• in Figure 4 (note nonlinear scale). Mean particle diameter in aqueous dispersions as a function of Ce0.495Sn0.495Pd0.01O2–δ concentration. Particle size measurements were carried out with a Mastersizer 2000 laser diffraction granulometer with the dispersion unit Hydro2000SM(A). Variation of the zeta

Mannich base-connected syntheses mediated by ortho-quinone methides

• Petra Barta,
• Ferenc Fülöp and
• István Szatmári

Beilstein J. Org. Chem. 2018, 14, 560–575, doi:10.3762/bjoc.14.43

• , mutagenous properties were also shown. Freccero et al. examined the photogeneration by laser flash photolysis and reactivity of naphthoquinone methides as well as their activity as purine selective DNA alkylating agents [93]. Farrell et al. studied the mechanism of the cytotoxic action of naphthoquinone

• phenolic Mannich bases bearing functional groups that are suitable for cross-linking DNA; therefore, their antitumor effects could also be confirmed [96]. The formation of o-QMs and their biological properties were also illustrated by kinetic studies. Rokita et al. using laser flash photolysis showed that

Halogen-containing thiazole orange analogues – new fluorogenic DNA stains

• Aleksey A. Vasilev,
• Meglena I. Kandinska,
• Stanimir S. Stoyanov,
• Stanislava B. Yordanova,
• David Sucunza,
• Juan J. Vaquero,
• Obis D. Castaño,
• Stanislav Baluschev and
• Silvia E. Angelova

Beilstein J. Org. Chem. 2017, 13, 2902–2914, doi:10.3762/bjoc.13.283

• irradiation at 532 nm by 80 mW continuous wave frequency doubled DPSS (diode pumped solid state) laser, (Figures S21–S24, Supporting Information File 1). Computational studies Optimized structures of the preferred conformers of the cationic fragments of all dyes with the counterion I− (in the preffered