N,N'-(Hexane-1,6-diyl)bis(4-methyl-N-(oxiran-2-ylmethyl)benzenesulfonamide): Synthesis via cyclodextrin mediated N-alkylation in aqueous solution and further Prilezhaev epoxidation

• Julian Fischer,
• Simon Millan and
• Helmut Ritter

Beilstein J. Org. Chem. 2013, 9, 2834–2840, doi:10.3762/bjoc.9.318

• calibration, standard tin, indium, and zinc samples were used. Heating and cooling curves were determined between −30 and 130 °C at a heating rate of 15 °C/min. The Tg value was taken from the inflection point of the second heating curve. Electrospray ionization mass spectrometry (ESIMS) was conducted on a

Oligomeric epoxide–amine adducts based on 2-amino-N-isopropylacetamide and α-amino-ε-caprolactam: Solubility in presence of cyclodextrin and curing properties

• Julian Fischer and
• Helmut Ritter

Beilstein J. Org. Chem. 2013, 9, 2803–2811, doi:10.3762/bjoc.9.315

• zinc samples were used. Heating and cooling curves were determined between −30 and 50 °C or −30 and 60 °C at a heating rate of 15 °C/min. The Tg values were calculated from the arithmetic average of the inflection points of the second, third and fourth heating curve. Electrospray ionization mass

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

Synthesis and antibacterial activity of monocyclic 3-carboxamide tetramic acids

• Yong-Chul Jeong and
• Mark G. Moloney

Beilstein J. Org. Chem. 2013, 9, 1899–1906, doi:10.3762/bjoc.9.224

• , respectively) with residual solvent peaks as the internal reference. Mass spectra (MS) and high-resolution mass spectra (HRMS) were obtained with Micro Mass LCT and GCT spectrometers under the conditions of electrospray ionization (ESI) and chemical ionization (CI) respectively, and values were reported as a

Stability of SG1 nitroxide towards unprotected sugar and lithium salts: a preamble to cellulose modification by nitroxide-mediated graft polymerization

• Guillaume Moreira,
• Laurence Charles,
• Mohamed Major,
• Florence Vacandio,
• Yohann Guillaneuf,
• Catherine Lefay and
• Didier Gigmes

Beilstein J. Org. Chem. 2013, 9, 1589–1600, doi:10.3762/bjoc.9.181

• supporting electrolyte (NaCLO4 or TBAPF6) 0.1 mol·L−1. High-resolution mass spectrometry experiments were performed by using a QStar Elite mass spectrometer (Applied Biosystems SCIEX, Concord, ON, Canada) equipped with an electrospray ionization source operated in the positive mode. The capillary voltage was

A study on electrospray mass spectrometry of fullerenol C₆₀(OH)₂₄

• Mihaela Silion,
• Andrei Dascalu,
• Mariana Pinteala,
• Bogdan C. Simionescu and
• Cezar Ungurenasu

Beilstein J. Org. Chem. 2013, 9, 1285–1295, doi:10.3762/bjoc.9.145

• characterization by electrospray ionization mass spectrometry (ESI-MS) have become essential for fullerenol research. Fullerenols C60(OH)18–44 are very small neutral molecules with the highest density of hydroxy groups on a given particle surface (up to 10.7 OH/nm2) [21] achieved so far, complicating spectra

• following Q/TOF MS parameters were optimized: electrospray ionization (positive- and negative-ion mode), drying gas (N2) flow rate, drying-gas temperature, nebulizer pressure, capillary voltage, and fragmentor voltage. The mass scale was calibrated by the standard calibration procedure with compounds

Linkage of α-cyclodextrin-terminated poly(dimethylsiloxanes) by inclusion of quasi bifunctional ferrocene

• Helmut Ritter,
• Berit Knudsen and
• Valerij Durnev

Beilstein J. Org. Chem. 2013, 9, 1278–1284, doi:10.3762/bjoc.9.144

• . This corresponds to an absorption frequency of 300 MHz for 1H NMR and 75 MHz for 13C {1H} NMR. For ESI-measurements on an ion-trap mass spectrometer API Finnigan LCQ Deca, the substances were dissolved in a suitable solvent at a concentration of 2 mg·mL−1. The ionization was carried out by electrospray

• ionization (ESI). The TEM images were obtained on a Zeiss EM 902A microscope at 80 kV. The samples were dissolved in chloroform and dripped on copper grids (Formvar/carbon film 400 mesh). After evaporation of the solvent, the remaining pure substances could be examined under a high vacuum (10−7 bar). The

Quantification of N-acetylcysteamine activated methylmalonate incorporation into polyketide biosynthesis

• Stephan Klopries,
• Uschi Sundermann and
• Frank Schulz

Beilstein J. Org. Chem. 2013, 9, 664–674, doi:10.3762/bjoc.9.75

• Accela HPLC-System (column Hypersil Gold, length 50 mm, inside diameter 1 mm, particle size 1.9 µm, ionization method: Electrospray Ionization). Products were characterized by NMR (1H, 13C) and HRMS. ESI-method for quantification of D3-label incorporation Mass-to-charge ratios of the extracts were

• electrospray ionization was carried out in positive (erythromycin)/negative (rapamycin) ionization mode by using a source voltage of 4 kV. The capillary voltage was set to 18 V, the capillary temperature to 275 °C, and the tube lens voltage to 115 V. Spectra were acquired in full scan centroid mode with a mass

Synthesis of 2,3-dihydronaphtho[2,3-d][1,3]thiazole-4,9-diones and 2,3-dihydroanthra[2,3-d][1,3]thiazole-4,11-diones and novel ring contraction and fusion reaction of 3H-spiro[1,3-thiazole-2,1'-cyclohexanes] into 2,3,4,5-tetrahydro-1H-carbazole-6,11-diones

• Lidia S. Konstantinova,
• Kirill A. Lysov,
• Ljudmila I. Souvorova and
• Oleg A. Rakitin

Beilstein J. Org. Chem. 2013, 9, 577–584, doi:10.3762/bjoc.9.62

• spectra were recorded on a Finnigan MAT INCOS 50 instrument by using electron impact ionization. High-resolution mass spectra (HRMS) were measured on a Bruker micrOTOF II instrument by using electrospray ionization (ESI) [23]. The measurements were done in a positive-ion mode (interface capillary voltage

Synthesis and evaluation of cell-permeable biotinylated PU-H71 derivatives as tumor Hsp90 probes

• Tony Taldone,
• Anna Rodina,
• Erica M. DaGama Gomes,
• Matthew Riolo,
• Hardik J. Patel,
• Raul Alonso-Sabadell,
• Danuta Zatorska,
• Maulik R. Patel,
• Sarah Kishinevsky and
• Gabriela Chiosis

Beilstein J. Org. Chem. 2013, 9, 544–556, doi:10.3762/bjoc.9.60

• = quartet, br = broad, m = multiplet), coupling constant (Hz), integration. High-resolution mass spectra were recorded on a Waters LCT Premier system. Low-resolution mass spectra were obtained on a Waters Acquity Ultra Performance LC with electrospray ionization and SQ detector. High-performance liquid

Chemoenzymatic synthesis and biological evaluation of enantiomerically enriched 1-(β-hydroxypropyl)imidazolium- and triazolium-based ionic liquids

• Paweł Borowiecki,
• Małgorzata Milner-Krawczyk and
• Jan Plenkiewicz

Beilstein J. Org. Chem. 2013, 9, 516–525, doi:10.3762/bjoc.9.56

• (+)-8a–c and (+)-8e–f, which are exceedingly viscous liquids (gums), all of the chiral hydroxy-functionalized imidazolium and one of the triazolium salts are liquid at room temperature. Final products were characterized by 1H, 13C NMR and FTIR spectroscopy as well as high-resolution electrospray

• ionization mass spectrometry (HRMS–ESI). Their structures were found to be spectroscopically well–defined, which was further confirmed by elemental analyses. For the purpose of biological tests, the racemic mixtures all of salts presented in Table 3 were synthesized. Antimicrobial activity of racemic ionic

Multivalent display of the antimicrobial peptides BP100 and BP143

• Imma Güell,
• Rafael Ferre,
• Kasper K. Sørensen,
• Esther Badosa,
• Iteng Ng-Choi,
• Emilio Montesinos,
• Eduard Bardají,
• Lidia Feliu,
• Knud J. Jensen and
• Marta Planas

Beilstein J. Org. Chem. 2012, 8, 2106–2117, doi:10.3762/bjoc.8.237

• and 5 in 99% purity, and their structure was confirmed by electrospray-ionization mass spectrometry (ESIMS). With templates and peptide aldehydes in hand, the four-stranded structure 3 was prepared from Galp and peptide aldehyde 4 (Scheme 2). First, the reaction was conducted in a 1:1 solution of

Preparation of mixed trialkyl alkylcarbonate derivatives of etidronic acid via an unusual route

• Petri A. Turhanen,
• Janne Weisell and
• Jouko J. Vepsäläinen

Beilstein J. Org. Chem. 2012, 8, 2019–2024, doi:10.3762/bjoc.8.228

• [32]. Diastereomeric ratios for each of the compounds 3a–d were calculated from the 31P NMR spectrum. Mass spectra were recorded on a quadrupole time-of-flight mass spectrometer by using electrospray ionization (ESI) with positive-ionization mode for compounds 3a–d and 4 and negative for compound 2

Automated three-component synthesis of a library of γ-lactams

• Erik Fenster,
• David Hill,
• Oliver Reiser and
• Jeffrey Aubé

Beilstein J. Org. Chem. 2012, 8, 1804–1813, doi:10.3762/bjoc.8.206

• TOF spectrometer for electrospray ionization (ESI). General procedure for the asymmetric organocatalyzed Michael addition of aldehyde 2{1} to maleimide 1{1} to produce 3{1,1} (Table 1) Propionaldehyde (2{1}) (31.2 μL, 0.433 mmol, 1.5 equiv) was added to a solution of N-phenylmaleimide (1{1}) (50.0 mg

Synthesis of trifunctional cyclo-β-tripeptide templates

• Frank Stein,
• Tahir Mehmood,
• Tilman Plass,
• Javid H. Zaidi and
• Ulf Diederichsen

Beilstein J. Org. Chem. 2012, 8, 1576–1583, doi:10.3762/bjoc.8.180

• % aq TFA), B (0.1% TFA in methanol) or C (0.1% TFA in MeCN) and water (0.1% TFA) within 30 minutes. Flow rates were taken as 1 mL/min for the analytical columns and 10 mL/min for preparative columns. All crude samples were dissolved in methanol or acetonitrile and filtered prior to use. Electrospray

• ionization (ESI) mass spectra were obtained on a Finnigan LCQ instrument. High-resolution mass spectra (HRMS) were obtained on a Bruker Apex IV FT-ICR-MS instrument. 1H NMR and 13C NMR spectra of samples dissolved in DMSO-d6, CDCl3 or acetone-d6 were recorded on a Varian Unity 300 (300 MHz) spectrometer

Studies on the substrate specificity of a GDP-mannose pyrophosphorylase from Salmonella enterica

• Lu Zou,
• Ruixiang Blake Zheng and
• Todd L. Lowary

Beilstein J. Org. Chem. 2012, 8, 1219–1226, doi:10.3762/bjoc.8.136

• by high-resolution electrospray ionization mass spectrometry revealed an ion with m/z = 604.0691, which corresponds to the [M − H]− ion (calcd m/z = 604.0699) of GDP-Manp. Having established that the enzyme GDP-ManPP was active, we carried out the same incubations for 9–13, and in all cases the

• . To confirm the identity of each GDP-Manp analogue, the product peaks were isolated and analysed by electrospray ionization mass spectrometry. For the reactions involving 9–12 a signal at m/z ≈ 618 was observed, as would be expected for the [M − H]− ion of the methylated GDP-Man derivatives (48–51

Partial thioamide scan on the lipopeptaibiotic trichogin GA IV. Effects on folding and bioactivity

• Marta De Zotti,
• Barbara Biondi,
• Cristina Peggion,
• Matteo De Poli,
• Haleh Fathi,
• Simona Oancea,
• Claudio Toniolo and
• Fernando Formaggio

Beilstein J. Org. Chem. 2012, 8, 1161–1171, doi:10.3762/bjoc.8.129

• of 10−1 deg·cm2·g−1) were measured at 20 °C on a Perkin-Elmer PE241 polarimeter, with a 1 dm path length cell, at the D-wavelength of sodium (589 nm). The concentration of each compound (c) is given in mg/cL. Mass spectroscopy (electrospray ionization, ESIMS) was performed by using a PerSeptive

Synthesis of 4” manipulated Lewis X trisaccharide analogues

• Christopher J. Moore and
• France-Isabelle Auzanneau

Beilstein J. Org. Chem. 2012, 8, 1134–1143, doi:10.3762/bjoc.8.126

• ), doublet of doublet of doublet (ddd), broad singlet (bs), broad triplet (bt), broad doublet of doublet (bdd) and multiplet (m). Mass spectra were obtained with electrospray ionization (ESI) on a high-resolution mass spectrometer. TLC were performed on precoated aluminum plates with Silica Gel 60 F254 and

Synthesis and anion recognition properties of shape-persistent binaphthyl-containing chiral macrocyclic amides

• Marco Caricato,
• Nerea Jordana Leza,
• Claudia Gargiulli,
• Giuseppe Gattuso,
• Daniele Dondi and
• Dario Pasini

Beilstein J. Org. Chem. 2012, 8, 967–976, doi:10.3762/bjoc.8.109

• spectrophotometers. Mass spectra were recorded by using an electrospray ionization instrument. Optical rotations were measured on a polarimeter with a sodium lamp (λ = 589 nm) and are reported as follows: [α]Drt (c = g (100 mL solution)−1). CD spectroscopy was performed by using a spectropolarimeter; spectra were

An easily accessible sulfated saccharide mimetic inhibits in vitro human tumor cell adhesion and angiogenesis of vascular endothelial cells

• Grazia Marano,
• Claas Gronewold,
• Martin Frank,
• Anette Merling,
• Christian Kliem,
• Sandra Sauer,
• Manfred Wiessler,
• Eva Frei and
• Reinhard Schwartz-Albiez

Beilstein J. Org. Chem. 2012, 8, 787–803, doi:10.3762/bjoc.8.89

• , Rheinstetten, Germany) with Me4Si (δ = 0) as the internal standard. Mass spectrometry electrospray ionization (ESI–MS) measurements were recorded on a Finnigan MAT TSQ 7000 instrument. All measurements were performed at the central spectroscopy unit of the DKFZ. Synthesis of 3,4-bis{[(β-D-galactopyranosyl)oxy

Triterpenoid saponins from the roots of Acanthophyllum gypsophiloides Regel

• Elena A. Khatuntseva,
• Vladimir M. Men’shov,
• Alexander S. Shashkov,
• Yury E. Tsvetkov,
• Rodion N. Stepanenko,
• Raymonda Ya. Vlasenko,
• Elvira E. Shults,
• Genrikh A. Tolstikov,
• Tatjana G. Tolstikova,
• Dimitri S. Baev,
• Vasiliy A. Kaledin,
• Nelli A. Popova,
• Valeriy P. Nikolin,
• Pavel P. Laktionov,
• Anna V. Cherepanova,
• Tatiana V. Kulakovskaya,
• Ekaterina V. Kulakovskaya and
• Nikolay E. Nifantiev

Beilstein J. Org. Chem. 2012, 8, 763–775, doi:10.3762/bjoc.8.87

• Bruker micrоTOF II instrument by using electrospray ionization (ESI) [28]. The measurements were done in a positive-ion mode (interface capillary voltage: 4500 V) or in a negative-ion mode (3200 V); mass range from m/z 50–3000 Da; external or internal calibration was achieved with electrospray calibrant

Enantioselective supramolecular devices in the gas phase. Resorcin[4]arene as a model system

• Caterina Fraschetti,
• Matthias C. Letzel,
• Antonello Filippi,
• Maurizio Speranza and
• Jochen Mattay

Beilstein J. Org. Chem. 2012, 8, 539–550, doi:10.3762/bjoc.8.62

• the attention will be focussed on the most recent results obtained by our group with this particular kinetic method. Methodology The proton-bound [M∙H∙G]+ aggregates (M: chiral hosting resorcin[4]arene; G: guest biomolecule) were generated by electrospray ionization (ESI) of M/G methanolic mixtures

Branching out at C-2 of septanosides. Synthesis of 2-deoxy-2-C-alkyl/aryl septanosides from a bromo-oxepine

• Supriya Dey and
• Narayanaswamy Jayaraman

Beilstein J. Org. Chem. 2012, 8, 522–527, doi:10.3762/bjoc.8.59

• Merck plates coated with silica gel GF254 (0.25 mm). Silica gel (230–400 mesh) was used for column chromatography. Optical rotations were recorded on a JASCO Model P-1020 polarimeter at the sodium D line at 24 °C. High-resolution mass spectra were obtained from a Q-TOF instrument by the electrospray

• ionization (ESI) technique. 1H and 13C NMR spectral analyses were performed on 400 MHz and 100 MHz spectrometers, respectively, with the residual solvent signal acting as the internal standard. COSY and HSQC analyses were performed on a 400 MHz NMR spectrometer. Methyl 2-deoxy-2-C-(2-(tert-butoxycarbonyl

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

• B in 15 min (solvent A: water/formic acid (999:1); solvent B: acetonitrile/formic acid (999.4:0.6)). Detection was carried out at 230, 260, 280, 360, and 435 nm. Electrospray ionization (positive and negative ionization) in Ultra Scan mode with capillary voltage of 3.5 kV and drying gas temperature

Self-assembly of Ru₄ and Ru₈ assemblies by coordination using organometallic Ru(II)₂ precursors: Synthesis, characterization and properties

• Sankarasekaran Shanmugaraju,
• Dipak Samanta and
• Partha Sarathi Mukherjee

Beilstein J. Org. Chem. 2012, 8, 313–322, doi:10.3762/bjoc.8.34

• salts in high yields and were characterized fully by multinuclear (1H, 13C and 19F) NMR, infrared (IR) and electrospray ionization mass spectrometry (ESIMS). In addition, the molecular structure of macrocycle 2a was established unequivocally by single-crystal X-ray diffraction analysis and adopts a

• information about the exact composition and nuclearity of the final products. Electrospray ionization mass spectrometry (ESIMS) can be used as a soft-ionization method to elucidate the exact composition of the product [12]. The ESIMS analysis confirmed the formation of the rather unexpected [2 + 1] self