Microfluidic radiosynthesis of [¹⁸F]FEMPT, a high affinity PET radiotracer for imaging serotonin receptors

• Thomas Lee Collier,
• Steven H. Liang,
• J. John Mann,
• Neil Vasdev and
• J. S. Dileep Kumar

Beilstein J. Org. Chem. 2017, 13, 2922–2927, doi:10.3762/bjoc.13.285

• LC–MS, using the trapping system to improve the sensitivity. Red line is the UV spectra observed at 254 nm. Column = 3 µm, 4.6 × 150 mm C18, Phenomenex, Luna. Solvent MeCN:0.1% formic acid, Flow rate = 1 mL/min, Gradient from 20% ACN to 95% ACN at 10 minutes, hold for 2 minutes at 95% MeCN. Insets

BODIPY-based fluorescent liposomes with sesquiterpene lactone trilobolide

• Ludmila Škorpilová,
• Silvie Rimpelová,
• Michal Jurášek,
• Miloš Buděšínský,
• Jana Lokajová,
• Roman Effenberg,
• Petr Slepička,
• Tomáš Ruml,
• Eva Kmoníčková,
• Pavel B. Drašar and
• Zdeněk Wimmer

Beilstein J. Org. Chem. 2017, 13, 1316–1324, doi:10.3762/bjoc.13.128

• and fluorescence spectra of compounds 3–6. UV spectra (part A) were recorded with a concentration of 10 μM in DCM and fluorescence spectra (part B) with a concentration of 0.1 μM in DCM using an excitation wavelength of 475 nm. A typical Stokes shift (10 nm) is demonstrated for construct 6 (part C

Cycloheximide congeners produced by Streptomyces sp. SC0581 and photoinduced interconversion between (E)- and (Z)-2,3-dehydroanhydrocycloheximides

• Li Yang,
• Ping Wu,
• Jinghua Xue,
• Huitong Tan,
• Zheng Zhang and
• Xiaoyi Wei

Beilstein J. Org. Chem. 2017, 13, 1039–1049, doi:10.3762/bjoc.13.103

• state, arising from the chiral nature of molecules. Experimental General experimental procedures Optical rotations were recorded in MeOH on a Perkin-Elmer 343 spectropolarimeter. UV spectra and ECD spectra were obtained simultaneously on a Chirascan CD spectrometer (Applied Photophysics Ltd., England

Characterization of the synthetic cannabinoid MDMB-CHMCZCA

• Carina Weber,
• Stefan Pusch,
• Dieter Schollmeyer,
• Sascha Münster-Müller,
• Michael Pütz and
• Till Opatz

Beilstein J. Org. Chem. 2016, 12, 2808–2815, doi:10.3762/bjoc.12.279

• CO and/or a cyclohexyl radical or methylenecyclohexane. As MDMB-CHMCZCA bears a stereogenic center at C-1', the elucidation of the absolute configuration of the sample was attempted by ECD spectroscopy. While the UV spectra can be adequately predicted by TD-DFT calculations (time-dependent density

• . Enthalpy-Boltzmann-averaged UV and ECD spectra were then generated in all cases. Using SpecDis 1.64 [16], the experimental and calculated UV spectra were fitted in the range from 200 nm to 400 nm using screening values of 0.1 eV to 0.5 eV for the line broadening σ/γ as well as −60 nm to +60 nm for the

Enzymatic synthesis and phosphorolysis of 4(2)-thioxo- and 6(5)-azapyrimidine nucleosides by E. coli nucleoside phosphorylases

• Vladimir A. Stepchenko,
• Anatoly I. Miroshnikov,
• Frank Seela and
• Igor A. Mikhailopulo

Beilstein J. Org. Chem. 2016, 12, 2588–2601, doi:10.3762/bjoc.12.254

• (10 mL) and put on top of silica gel column (2 × 10 cm) that was eluted with chloroform/methanol, 30:1 (v/v). 2-Thio-6-azathymidine (5b) was obtained as white powder (25 mg, 0.097 mmol, 50%), that was recrystallized from acetonitrile; mp 174–176 °C. UV spectra (H2O): λmax, nm (ε, M−1∙cm−1): 272

• )uracil (lower structures). The UV spectra of 4-thio-2′-deoxyuridine (1b). The UV spectra of 6-aza-2-thiothymidine (5b). Enzymatic synthesis of 2-deoxy-β-D-ribofuranosides 1b–5b of the heterocyclic bases 1a–5a. Regents and conditions: dG/base ratio: 1.5:1.0 (mol), 10 mM K,Na-phosphate buffer; 40 °C, 48–72

Biomimetic synthesis and HPLC–ECD analysis of the isomers of dracocephins A and B

• Viktor Ilkei,
• András Spaits,
• Anita Prechl,
• Áron Szigetvári,
• Zoltán Béni,
• Miklós Dékány,
• Csaba Szántay Jr,
• Judit Müller,
• Árpád Könczöl,
• Ádám Szappanos,
• Attila Mándi,
• Sándor Antus,
• Ana Martins,
• Attila Hunyadi,
• György Tibor Balogh,
• György Kalaus (†),
• Hedvig Bölcskei,
• László Hazai and
• Tibor Kurtán

Beilstein J. Org. Chem. 2016, 12, 2523–2534, doi:10.3762/bjoc.12.247

• -810 CD spectropolarimeter equipped with a 1 cm HPLC flow cell and the baseline was zeroed after the start of each run. The on-line ECD and UV spectra were recorded simultaneously by stopping the flow at the UV absorption maximum of each peak. ECD ellipticity values (Φ) were not corrected for

Inhibition of peptide aggregation by means of enzymatic phosphorylation

• Kristin Folmert,
• Malgorzata Broncel,
• Hans v. Berlepsch,
• Christopher H. Ullrich,
• Mary-Ann Siegert and
• Beate Koksch

Beilstein J. Org. Chem. 2016, 12, 2462–2470, doi:10.3762/bjoc.12.240

• by dissolving the purified, Abz labeled peptide in HFIP (≈1 mg mL−1) and sonicating for 15 minutes to dissolve all aggregates. 50 µL of this solution were aliquoted and dried under nitrogen flow, before the residue was dissolved in 1 mL 50 mM Tris/HCl buffer containing 10 mM MgCl2 at pH 7.5. UV

• spectra were recorded in a 1 cm path length cuvette using a Cary 50 UV–vis spectrophotometer (Varian, Palo Alto, CA, USA) and the absorbance maximum at 312 nm was compared to a standard curve of the dipeptide H2N-Abz-Gly-OH·HCl to calculate the concentration of the peptide stock solution. The stock

Varioloid A, a new indolyl-6,10b-dihydro-5aH-[1]benzofuro[2,3-b]indole derivative from the marine alga-derived endophytic fungus Paecilomyces variotii EN-291

• Peng Zhang,
• Xiao-Ming Li,
• Xin-Xin Mao,
• Attila Mándi,
• Tibor Kurtán and
• Bin-Gui Wang

Beilstein J. Org. Chem. 2016, 12, 2012–2018, doi:10.3762/bjoc.12.188

• an Optical Activity AA-55 polarimeter. UV spectra were measured by a Lengguang Gold S54 photometer. ECD data were collected using JASCO J-715 or J-810 spectropolarimeters. NMR data were recorded on a Bruker Avance 500 MHz spectrometer with TMS as internal standard. Low and high resolution ESI-mass

The role of alkyl substituents in deazaadenine-based diarylethene photoswitches

• Christopher Sarter,
• Michael Heimes and
• Andres Jäschke

Beilstein J. Org. Chem. 2016, 12, 1103–1110, doi:10.3762/bjoc.12.106

• irreversible reaction. This decay is strongest for phenyl derivative 1c which loses ~50% of its absorbance upon an irradiation of 1 hour. The same three tendencies can also be observed when the UV spectra are measured in ethanol and methanol (Supporting Information File 1, Figures S2 and S3), indicating that

Interactions of cyclodextrins and their derivatives with toxic organophosphorus compounds

• Sophie Letort,
• Sébastien Balieu,
• William Erb,
• Géraldine Gouhier and
• François Estour

Beilstein J. Org. Chem. 2016, 12, 204–228, doi:10.3762/bjoc.12.23

• technics [43]. Despite the pronounced solubility changes consistent with complex formation, little variations in the UV spectra, combined with the guest’s small chemical shifts observed in 1H NMR experiments (0.01–0.06 ppm), suggest the formation of external complexes rather than an inclusion complex

Determination of formation constants and structural characterization of cyclodextrin inclusion complexes with two phenolic isomers: carvacrol and thymol

• Miriana Kfoury,
• David Landy,
• Steven Ruellan,
• Lizette Auezova,
• Hélène Greige-Gerges and
• Sophie Fourmentin

Beilstein J. Org. Chem. 2016, 12, 29–42, doi:10.3762/bjoc.12.5

• an algorithmic treatment applied to the first derivatives of UV spectra. Experiments were done in triplicate. Phase solubility studies Phase solubility studies were carried out as described by Higuchi and Connors [56]. Excess amounts of 1 or 2 were added to 1 mL of CD solution at different

Synthesis of cyclic N¹-pentylinosine phosphate, a new structurally reduced cADPR analogue with calcium-mobilizing activity on PC12 cells

• Ahmed Mahal,
• Stefano D’Errico,
• Nicola Borbone,
• Brunella Pinto,
• Agnese Secondo,
• Valeria Costantino,
• Valentina Tedeschi,
• Giorgia Oliviero,
• Vincenzo Piccialli and
• Gennaro Piccialli

Beilstein J. Org. Chem. 2015, 11, 2689–2695, doi:10.3762/bjoc.11.289

• 4.8 × 150 mm C-18 reversed-phase column (particle size 5 µm) eluted with a linear gradient of CH3CN in 0.1 M triethylammonium bicarbonate (TEAB) buffer (from 0 to 50% in 45 min, flow 1.3 mL/min). UV spectra were recorded on a Jasco V-530 UV spectrophotometer. High-resolution MS spectra were recorded

Bromotyrosine-derived alkaloids from the Caribbean sponge Aplysina lacunosa

• Qun Göthel,
• Thanchanok Sirirak and
• Matthias Köck

Beilstein J. Org. Chem. 2015, 11, 2334–2342, doi:10.3762/bjoc.11.254

• . Experimental UV spectra were recorded during HPLC separation with a DAD detector (JASCO MD-2010 Plus). CD spectra were recorded on a JASCO J-810 spectropolarimeter. Low and high resolution ESIMS was performed with a Bruker micrOTOFLC mass spectrometer. Mass calibration was performed using sodium formate

Photoinduced 1,2,3,4-tetrahydropyridine ring conversions

• Baiba Turovska,
• Henning Lund,
• Viesturs Lūsis,
• Anna Lielpētere,
• Edvards Liepiņš,
• Sergejs Beljakovs,
• Inguna Goba and
• Jānis Stradiņš

Beilstein J. Org. Chem. 2015, 11, 2166–2170, doi:10.3762/bjoc.11.234

• (Figure 3) has only one absorption band at λmax = 282 nm in the range of 250–900 nm which corresponds to the spin allowed S→S* transition (ε = 19000). If a series of UV spectra is recorded after subsequent periods of 1 min irradiation of the sample with an external UV lamp (254 nm, 8 W), the absorption

The marine sponge Agelas citrina as a source of the new pyrrole–imidazole alkaloids citrinamines A–D and N-methylagelongine

• Christine Cychon,
• Ellen Lichte and
• Matthias Köck

Beilstein J. Org. Chem. 2015, 11, 2029–2037, doi:10.3762/bjoc.11.220

• min: 10% MeCN/90% HCOOH (0.1%); 30 min: 60% MeCN/40% HCOOH (0.1%) with a flow rate of 0.4 mL min−1]. Preparative chromatography: Prontosil Eurobond C18 column (20 mm × 250 mm, 5 µm) with a MeCN/TFA (0.1%) gradient. UV spectra were recorded during HPLC analysis with a DAD (Agilent). Animal material The

Chiroptical properties of 1,3-diphenylallene-anchored tetrathiafulvalene and its polymer synthesis

• Masashi Hasegawa,
• Junta Endo,
• Seiya Iwata,
• Toshiaki Shimasaki and
• Yasuhiro Mazaki

Beilstein J. Org. Chem. 2015, 11, 972–979, doi:10.3762/bjoc.11.109

• -substituted allenes 1–3. (a) ECD spectra of (R)-(−)-3 (3.5 × 10−5 M), (S)-(+)-3 (3.8 × 10−5 M), (R)-(−)-9 (3.0 × 10−5 M), and (S)-(+)-9 (2.9 × 10−5 M) in CH2Cl2 together with the simulated ECD spectra of 3 and 9 in (R)-configuration. (b) UV spectra of 3 (3.5 × 10−5 M) and 9 (3.8 × 10−5 M) in CH2Cl2. (a) UV

Inclusion of trans-resveratrol in methylated cyclodextrins: synthesis and solid-state structures

• Lee Trollope,
• Dyanne L. Cruickshank,
• Terence Noonan,
• Susan A. Bourne,
• Milena Sorrenti,
• Laura Catenacci and
• Mino R. Caira

Beilstein J. Org. Chem. 2014, 10, 3136–3151, doi:10.3762/bjoc.10.331

• syringe filters and diluted appropriately. The concentration of RSV was determined using UV–vis spectrophotometry at a wavelength of 316 nm. The UV spectra were recorded on a GCB Cintra 20 UV–vis spectrometer over a wavelength range of 200–500 nm at a scanning rate of 200 nm min−1. The extinction

Synthesis and characterization of pH responsive D-glucosamine based molecular gelators

• Navneet Goyal,
• Hari P. R. Mangunuru,
• Bargav Parikh,
• Sonu Shrestha and
• Guijun Wang

Beilstein J. Org. Chem. 2014, 10, 3111–3121, doi:10.3762/bjoc.10.328

• released. That the absorption of released naproxen at 9 h is greater than the naproxen control is caused by the p-methoxybenzaldehyde generated from the gelator molecule’s decomposition. p-Methoxybenzaldehyde exhibits a strong absorption in the wavelength range of 260–320 nm. The UV spectra of the gelator

• 16 under the same acidic conditions are shown in Figure S3 (Supporting Information File 1), and the full range of UV spectra of the released naproxen are shown in Figure S4, Supporting Information File 1. Conclusion In summary, we have synthesized and studied a new series of D-glucosamine derivatives

Trogopterins A–C: Three new neolignans from feces of Trogopterus xanthipes

• Soyoon Baek,
• Xuikui Xia,
• Byung Sun Min,
• Chanil Park and
• Sang Hee Shim

Beilstein J. Org. Chem. 2014, 10, 2955–2962, doi:10.3762/bjoc.10.313

• with a Jasco P1000 digital polarimeter. UV spectra were recorded by a Hewlett Packard 8453 UV–vis spectrometer. CD spectra were obtained with a Jasco J-715 circular dichroism spectrophotometer. 1D and 2D NMR were performed on a VNS 600 MHz spectrometer operating at 600 MHz for protons and 150 MHz for

Synthesis and characterization of a new photoinduced switchable β-cyclodextrin dimer

• Florian Hamon,
• Claire Blaszkiewicz,
• Marie Buchotte,
• Estelle Banaszak-Léonard,
• Hervé Bricout,
• Sébastien Tilloy,
• Eric Monflier,
• Christine Cézard,
• Laurent Bouteiller,
• Christophe Len and
• Florence Djedaini-Pilard

Beilstein J. Org. Chem. 2014, 10, 2874–2885, doi:10.3762/bjoc.10.304

• ; HRMS–ESI (m/z): [M + Na]+ calcd for C30H46N4O6Na, 581.3315; found, 581.3299. Overlaid UV spectra of the irradiation of AZO-CDim 1 (a) from 0 to 120 min at 365 nm and then (b) from 0 to 90 min at 254 nm; (c = 10−4 M, water, 6 W lamp). HPLC quantification of the cis/trans ratio of AZO-CDim 1 before

Synthesis and characterization of a hyper-branched water-soluble β-cyclodextrin polymer

• Francesco Trotta,
• Fabrizio Caldera,
• Roberta Cavalli,
• Andrea Mele,
• Carlo Punta,
• Lucio Melone,
• Franca Castiglione,
• Barbara Rossi,
• Monica Ferro,
• Vincenza Crupi,
• Domenico Majolino,
• Valentina Venuti and
• Dominique Scalarone

Beilstein J. Org. Chem. 2014, 10, 2586–2593, doi:10.3762/bjoc.10.271

• between SF and the branched β-CD polymer was further supported by UV–vis spectroscopy. The UV spectra of SF in the absence and presence of increasing amounts of polymer are shown in Figure 7. A decrease of absorbance was observed for the UV band of FS (490 nm) and an increase of absorbance of a new band

Effect of cyclodextrin complexation on phenylpropanoids’ solubility and antioxidant activity

• Miriana Kfoury,
• David Landy,
• Lizette Auezova,
• Hélène Greige-Gerges and
• Sophie Fourmentin

Beilstein J. Org. Chem. 2014, 10, 2322–2331, doi:10.3762/bjoc.10.241

• variation between the absorbance of free and complexed forms of MO. All Kf values were calculated by an algorithmic treatment applied to the first derivatives of UV spectra in order to avoid any spectral influence of diffraction phenomena. Absorption studies were performed using a UV–visible dual-beam

Reversibly locked thionucleobase pairs in DNA to study base flipping enzymes

• Christine Beuck and
• Elmar Weinhold

Beilstein J. Org. Chem. 2014, 10, 2293–2306, doi:10.3762/bjoc.10.239

• restored (Figure 4). The UV spectra of the cross-linked duplex 1I6S-Et-S4U2 before and after addition of 1 mM DTT show the full reappearance of the band at long wavelength around 330 nm identical to the unlinked duplex 1I6S∙2U4S, corroborating that the linker was fully removed from both thionucleobases. In

• mol−1 cm−1 at 260 nm was derived from an experimental spectrum of the free nucleoside and the published extinction coefficient of 24,800 L mol−1 cm−1 at 342 nm [83]. For dI6S and dU4S the low absorption at 260 nm was neglected. UV spectra of duplex ODN were recorded from 220 nm to 365 nm at a DNA

• ), ethanethiol (EtSH, 2 mM), or no thiol reagent were added. UV spectra were recorded (DTT: 0 min; BME: 0 min, EtSH: 0–25 min in 5 min increments) from 300 nm to 365 nm to monitor the reappearance of the band >300 nm which is characteristic for the non-alkylated thionucleobases. At the end of each time course

Sacrolide A, a new antimicrobial and cytotoxic oxylipin macrolide from the edible cyanobacterium Aphanothece sacrum

• Naoya Oku,
• Miyako Matsumoto,
• Kohsuke Yonejima,
• Keijiroh Tansei and
• Yasuhiro Igarashi

Beilstein J. Org. Chem. 2014, 10, 1808–1816, doi:10.3762/bjoc.10.190

• as chemical shift reference signals. HRMS–ESI–TOF and LC–MS analyses were carried out by an Agilent 1200 HPLC-DAD system coupled with a Bruker micrOTOF mass spectrometer. Optical rotation and UV spectra were recorded on a JASCO DIP-3000 polarimeter and a Hitachi U-3210 spectrophotometer, respectively

• ). Supporting Information Supporting Information File 656: Procedures for chemical conversion/derivatization, NMR assignments, copies of NMR, MS and UV spectra for 1, NMR spectra for 2, 3, 3a and 3b. Acknowledgements This work was supported in part by the President’s Fund Initiative at the Toyama Prefectural

The chemoenzymatic synthesis of clofarabine and related 2′-deoxyfluoroarabinosyl nucleosides: the electronic and stereochemical factors determining substrate recognition by E. coli nucleoside phosphorylases

• Ilja V. Fateev,
• Konstantin V. Antonov,
• Irina D. Konstantinova,
• Tatyana I. Muravyova,
• Frank Seela,
• Roman S. Esipov,
• Anatoly I. Miroshnikov and
• Igor A. Mikhailopulo

Beilstein J. Org. Chem. 2014, 10, 1657–1669, doi:10.3762/bjoc.10.173

• laboratory. Experimental General methods NMR spectra: Bruker Avance-700-DRX (Bruker, Germany). Mass spectra: Agilent 6224, ESI-TOF, LC/MS (USA) in positive ion mode (ESI+) and negative ion mode (ESI−). The UV spectra were recorded on the UV-spectrophotometer Shimadzu UV-160 (Japan). The preparation of