Adsorption of RNA on mineral surfaces and mineral precipitates

• Elisa Biondi,
• Yoshihiro Furukawa,
• Jun Kawai and
• Steven A. Benner

Beilstein J. Org. Chem. 2017, 13, 393–404, doi:10.3762/bjoc.13.42

• (25 °C, 37 °C, 55 °C, 75 °C, or 95 °C), and incubated for two hours. After incubation, RNA was eluted from aragonite with 1 M formic acid, purified, and loaded on denaturing PAGE with a set of control samples where RNA was treated the same way, but in aqueous phase (see Materials and Methods

• to the tubes’ plastic, was released by washing the surfaces with 100 mM aqueous formic acid (100 µL); the released RNA was recovered in new tubes. These samples were subjected to three cycles of evaporation and resuspension in ddH2O to eliminate formic acid. The residue was then dissolved in 95

Stabilization of nanosized titanium dioxide by cyclodextrin polymers and its photocatalytic effect on the degradation of wastewater pollutants

• Tamás Zoltán Agócs,
• István Puskás,
• Erzsébet Varga,
• Mónika Molnár and
• Éva Fenyvesi

Beilstein J. Org. Chem. 2016, 12, 2873–2882, doi:10.3762/bjoc.12.286

• ) analytical column and elution with 45% acetonitrile and 0.05% formic acid in water at a flow rate of 1.0 mL/min. The column temperature was set to 40 °C. The samples were diluted with 50% acetonitrile in 1:1 ratio before injecting 5 μL. Characterization of the molecular weight distribution by HPLC The same

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

• and water (with 0.1% formic acid) were used as eluents at a total flow rate of 1.0 mL min−1 with the following gradient method: acetonitrile/water (+ 0.1% formic acid) = 10:90 (0–0.2 min), 10:90 to 90:10 (0.2–4.0 min), and 90:10 (4.0–6.0 min). An Ascentis Express C18 column (length: 3 cm, diameter

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

• ) silica. Racemic naringenin was purchased from Sigma-Aldrich and used without further purification. Preparative HPLC Chemicals and reagents Acetonitrile used in the preparative chromatographic separation was gradient grade LiChrosolv purchased from Merck. The formic acid was reagent grade from Sigma

• . Preparative separation procedure The sample (500 µL/injection) was loaded to a Kinetex 5 µm phenyl-hexyl AXIA packed 21.2 × 150 mm column in the concentration of 20 mg/mL. The separation was achieved with isocratic elution (75% HPLC grade water containing 0.1% formic acid, 25% acetonitrile containing 0.1

• % formic acid) at 25 °C. The flow rate was 21 mL/min. The fractions were collected based on UV absorption at 220 nm wavelength. Chiral HPLC–ECD analysis Chiral HPLC separations were carried out with a Jasco HPLC system on Chiralpak IC column (250 × 4.6 mm i.d.; 5 μm) using eluent hexane/acetonitrile 97:3

A direct method for the N-tetraalkylation of azamacrocycles

• Andrew J. Counsell,
• Angus T. Jones,
• Matthew H. Todd and
• Peter J. Rutledge

Beilstein J. Org. Chem. 2016, 12, 2457–2461, doi:10.3762/bjoc.12.239

• ][30], the simplest N-tetraalkyl cyclam derivative, this class of compounds has been extensively investigated [2]. While the N-tetramethyl derivative is readily accessed by treating cyclam with formaldehyde and formic acid [29], this transformation (the Eschweiler–Clarke methylation) [31] is not

Tunable microwave-assisted method for the solvent-free and catalyst-free peracetylation of natural products

• Manuela Oliverio,
• Paola Costanzo,
• Monica Nardi,
• Carla Calandruccio,
• Raffaele Salerno and
• Antonio Procopio

Beilstein J. Org. Chem. 2016, 12, 2222–2233, doi:10.3762/bjoc.12.214

• carrier gas) and by an DSQ II mass detector. Chromatography was performed using a Thermo Scientific Dionex Ultimate 3000 RS, injecting directly onto a Thermo Scientific Hypersil Gold C18 column (50 × 2.1 mm, 1.9 µm particle size), equilibrated in 95% solvent A (0.1% aqueous solution of formic acid), 5

The in situ generation and reactive quench of diazonium compounds in the synthesis of azo compounds in microreactors

• Faith M. Akwi and
• Paul Watts

Beilstein J. Org. Chem. 2016, 12, 1987–2004, doi:10.3762/bjoc.12.186

• ) column under the following conditions; flow rate: 1.2 mL/min, mobile phase (acetonitrile 0.1% formic acid (75:25)) equipped with a variable wavelength detector was used for sample analysis. The external standard calibration HPLC method was used to quantify the amount of coupler utilized in the reaction

Synthesis and NMR studies of malonyl-linked glycoconjugates of N-(2-aminoethyl)glycine. Building blocks for the construction of combinatorial glycopeptide libraries

• Markus Nörrlinger,
• Sven Hafner and
• Thomas Ziegler

Beilstein J. Org. Chem. 2016, 12, 1939–1948, doi:10.3762/bjoc.12.183

• ) and 3-oxo-3-(2-acetamido-2-deoxy-3,4,6-tetra-O-acetyl-β-D-galactopyranosylamino)propanoic acid (6d), respectively. The resulting AEG glycoconjugates 1a–d were converted into the corresponding free acids 2a–d in 97–98% yield by treatment with aqueous formic acid. The Fmoc group of compound 1c was

• , the tert-butyl ester groups of building blocks 1a–d were removed under acid conditions with a 2:1 mixture of formic acid and dichloromethane at room temperature to give the corresponding free acids 2a–d in 97–98% yield (Scheme 1, Table 2). Partially deprotected building block 3 was prepared from 1a as

A convenient route to symmetrically and unsymmetrically substituted 3,5-diaryl-2,4,6-trimethylpyridines via Suzuki–Miyaura cross-coupling reaction

• Dariusz Błachut,
• Joanna Szawkało and
• Zbigniew Czarnocki

Beilstein J. Org. Chem. 2016, 12, 835–845, doi:10.3762/bjoc.12.82

• , the forensic community treats them as "route-specific impurities" or "route markers". The formation of these compounds results from the condensation of the drug precursors, like arylacetones with formamide or ammonia, in the presence of formic acid. This leads to di- and tetrahydrobenzyl/arylpyridines

Three new trixane glycosides obtained from the leaves of Jungia sellowii Less. using centrifugal partition chromatography

• Luíse Azevedo,
• Larissa Faqueti,
• Marina Kritsanida,
• Antonia Efstathiou,
• Despina Smirlis,
• Gilberto C. Franchi Jr,
• Grégory Genta-Jouve,
• Sylvie Michel,
• Louis P. Sandjo,
• Raphaël Grougnet and
• Maique W. Biavatti

Beilstein J. Org. Chem. 2016, 12, 674–683, doi:10.3762/bjoc.12.68

• area of compounds in upper phase divided by that in the lower phase. Chromatographic conditions employed for the peak area measurement were column Acquity UPLC BEH C18 1.7 µm (2.1 × 50 mm), with a flow rate of 0.3 mL/min using gradient mode composed of formic acid 0.1% (A) and acetonitrile (B

Highly stable and reusable immobilized formate dehydrogenases: Promising biocatalysts for in situ regeneration of NADH

• Barış Binay,
• Dilek Alagöz,
• Deniz Yildirim,
• Ayhan Çelik and
• S. Seyhan Tükel

Beilstein J. Org. Chem. 2016, 12, 271–277, doi:10.3762/bjoc.12.29

• decrease operational costs. NAD+-dependent formate dehydrogenase (FDH, EC 1.2.1.2) catalyzes oxidation of formate to carbon dioxide (CO2) [6]. FDH is industrially used as coenzyme for the regeneration of NADH [7][8], as sensor for the determination of formic acid [9], and as catalyst for the production of

Supramolecular structures based on regioisomers of cinnamyl-α-cyclodextrins – new media for capillary separation techniques

• Gabor Benkovics,
• Ondrej Hodek,
• Martina Havlikova,
• Zuzana Bosakova,
• Pavel Coufal,
• Milo Malanga,
• Eva Fenyvesi,
• Andras Darcsi,
• Szabolcs Beni and
• Jindrich Jindrich

Beilstein J. Org. Chem. 2016, 12, 97–109, doi:10.3762/bjoc.12.11

• )-(−)-mandelic acid). Cations were separated in BGE consisted of 0.11 mol L−1 formic acid pH 2.3, while anions were separated in BGE with 10 mmol L−1 TRIS, pH 8.0 (pH was adjusted by formic acid). Because of the observation that the temperature differently influenced the size of the aggregates formed by Cin-α

New metathesis catalyst bearing chromanyl moieties at the N-heterocyclic carbene ligand

• Agnieszka Hryniewicka,
• Szymon Suchodolski,
• Agnieszka Wojtkielewicz,
• Jacek W. Morzycki and
• Stanisław Witkowski

Beilstein J. Org. Chem. 2015, 11, 2795–2804, doi:10.3762/bjoc.11.300

• (2,2,5,7,8-pentamethylchroman-6-yl)ethane-1,2-diamine (13) To a solution of 2,2,5,7,8-pentamethylchromanyl-6-amine (12, 500 mg, 2.3 mmol) in ethanol (96%, 20 mL), 2,3-dihydroxy-1,4-dioxane (138 mg, 1.15 mmol) and two drops of formic acid were added in a manner similar to a that described in [40]. The

Biocatalysis for the application of CO₂ as a chemical feedstock

• Apostolos Alissandratos and
• Christopher J. Easton

Beilstein J. Org. Chem. 2015, 11, 2370–2387, doi:10.3762/bjoc.11.259

• . Zeolite systems utilising Ge or Si, recently described, were able to efficiently dehydrogenate formic acid. This was guided through computational calculations, allowing the design of a zeolite catalyst displaying over 94% selectivity over the counter-productive formate dehydration reaction [145]. The

• mediated application of solar energy for the fixation of CO2. Finally, electrons can be stored within chemical species that may then be oxidised by organisms to regenerate the electrons on-demand [20]. Hydrogen and formic acid appear most suited for such applications, due to their chemical properties, and

Efficient synthetic protocols for the preparation of common N-heterocyclic carbene precursors

• Morgan Hans,
• Jan Lorkowski,
• Albert Demonceau and
• Lionel Delaude

Beilstein J. Org. Chem. 2015, 11, 2318–2325, doi:10.3762/bjoc.11.252

• needs to be checked beforehand. Formic acid is sometimes added as a catalyst but does not seem to be mandatory, maybe because glyoxal is often contaminated with glyoxylic and oxalic acids, especially upon prolonged storage under aerobic conditions. More significant alterations were brought to the

• presence of a catalytic amount of formic acid. In this reaction, the orthoester served both as a solvent and a precarbenic C2 provider. Following the seminal contribution of Arduengo and co-workers, several other research groups proposed experimental procedures for the preparation of imidazolinium salts

• this condensation in dichloromethane containing formic acid as a catalyst and anhydrous magnesium sulfate as a dehydrating agent. We found this procedure difficult to reproduce. Moreover, a rather tedious work-up was required to separate and to purify the product. Inspired by a report from Cole and co

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

• suggested the nitrogen N-10 in the aromatic ring which is connected to the aliphatic chain at position C-9 (59.8 ppm). The correlations H-11 and H-15 to C-9 proved this substitution and the correlations H-11 and H-13 to C-16 (163.2 ppm) showed the second substituent to be a formic acid group. The structure

The enantioselective synthesis of (S)-(+)-mianserin and (S)-(+)-epinastine

• Piotr Roszkowski,
• Jan. K. Maurin and
• Zbigniew Czarnocki

Beilstein J. Org. Chem. 2015, 11, 1509–1513, doi:10.3762/bjoc.11.164

• ruthenium complex 11 which contain (1R,2R)- or (1S,2S)-N-tosyl-1,2-cyclohexanediamine as chiral ligand (Figure 2). The reaction was carried out in acetonitrile using an azeotropic mixture of formic acid/triethylamine as hydrogen source with 50:1 substrate to catalyst ratio. Under these conditions the

A simple and efficient method for the preparation of 5-hydroxy-3-acyltetramic acids

• Johanna Trenner and
• Evgeny V. Prusov

Beilstein J. Org. Chem. 2015, 11, 323–327, doi:10.3762/bjoc.11.37

• organic phase was purified with preparative HPLC (Machery Nagel, Nucleodur VP250/21 C18 Gravity, 5 µm; 280 nm; 90:10 MeCN/(H2O + 1% formic acid); 10 mL/min) to give the corresponding 5-hydroxy-3-cyclohexanecarbonyl tetramic acid as a white solid. Naturally occurring 5-hydroxylated 3-acyltetramic acids

Cross-dehydrogenative coupling for the intermolecular C–O bond formation

• Igor B. Krylov,
• Vera A. Vil’ and
• Alexander O. Terent’ev

Beilstein J. Org. Chem. 2015, 11, 92–146, doi:10.3762/bjoc.11.13

• carboxylic acids occurs in benzene in the presence of KMnO4 to form coupling products 221 (Scheme 46) [211]. Acids were present in a large excess relative to ketones. The synthesis was successfully accomplished, in particular, with readily oxidizable formic acid; the corresponding formates (for example, 221b

An integrated photocatalytic/enzymatic system for the reduction of CO₂ to methanol in bioglycerol–water

• Michele Aresta,
• Angela Dibenedetto,
• Tomasz Baran,
• Antonella Angelini,
• Przemysław Łabuz and
• Wojciech Macyk

Beilstein J. Org. Chem. 2014, 10, 2556–2565, doi:10.3762/bjoc.10.267

• , namely: formate dehydrogenase (FateDH), formaldehyde dehydrogenase (FaldDH), and alcohol dehydrogenase (ADH). These enzymes promote the cascade reduction of CO2 to methanol through formic acid (FateDH), formaldehyde (FaldDH) and aldehyde (ADH). The reduction process is enabled by NADH, which is oxidized

Electrocarboxylation: towards sustainable and efficient synthesis of valuable carboxylic acids

• Roman Matthessen,
• Jan Fransaer,
• Koen Binnemans and
• Dirk E. De Vos

Beilstein J. Org. Chem. 2014, 10, 2484–2500, doi:10.3762/bjoc.10.260

• promising technology for environmentally friendly chemical processes [26]. The electroreduction of CO2 can be applied for the synthesis of fuels like formic acid [27], methanol [28] or methane [29] via two-, six- and eight-electron reductions, respectively (Scheme 2). This way electric energy from periodic

• acids is a very interesting approach in this respect, minimizing the amount of process steps and waste (Scheme 6b). Protons produced at the anode, however, can have a detrimental effect on the electrocarboxylation efficiency, through cathodic formation of hydrogen, formic acid and other side products

• catholyte decreases the total current efficiency, due to the formation of formic acid [41][42]. It must be noted that, when using an aqueous and organic solvent in anolyte and catholyte, respectively, the transfer of hydrated protons through the membrane will cause water to enter the catholyte. Protons in

A small azide-modified thiazole-based reporter molecule for fluorescence and mass spectrometric detection

• Stefanie Wolfram,
• Hendryk Würfel,
• Stefanie H. Habenicht,
• Christine Lembke,
• Phillipp Richter,
• Eckhard Birckner,
• Rainer Beckert and
• Georg Pohnert

Beilstein J. Org. Chem. 2014, 10, 2470–2479, doi:10.3762/bjoc.10.258

• photodiode array detector using the solvents A (water/acetonitrile/formic acid 98:2:0.1; v/v/v) and B (acetonitrile/0.1% formic acid; v/v). The peaks of equimolar amounts were integrated at their absorption maxima resulting in the highest integrated peak area for NBD (9) followed by BPT (1) (Figure 5A). BPT

• ) measured with C18-UPLC–ESIMS using a linear gradient of solvents A (water/acetonitrile/formic acid 98:2:0.1; v/v/v) and B (acetonitrile/0.1% formic acid; v/v) and solvent composition and masses of imines 11–14 formed in a model reaction between L-lysine and DDY (10) followed by CuAAC with the different

Synthesis of aromatic glycoconjugates. Building blocks for the construction of combinatorial glycopeptide libraries

• Markus Nörrlinger and
• Thomas Ziegler

Beilstein J. Org. Chem. 2014, 10, 2453–2460, doi:10.3762/bjoc.10.256

• formic acid and dichloromethane at room temperature to give the corresponding free acids, i.e., building blocks 1a–d and 2a–d in 68–95% yield (Table 2). In order to demonstrate that building blocks 1 and 2 are indeed suitable for the construction of combinatorial glycopeptide libraries we chose glucose

• (Scheme 2). Treatment of 6 and 8 with a 2:1 mixture of formic acid and dichloromethane at room temperature for 38 h, as described for the preparation of building blocks 1 and 2 (see Table 2), afforded the benzoic acid derivatives 15 and 18 in 93% yield for each. Likewise, treatment of 5 and 8 with 20

A versatile δ-aminolevulinic acid (ΑLA)-cyclodextrin bimodal conjugate-prodrug for PDT applications with the help of intracellular chemistry

• Chrysie Aggelidou,
• Theodossis A. Theodossiou,
• Antonio Ricardo Gonçalves,
• Mariza Lampropoulou and
• Konstantina Yannakopoulou

Beilstein J. Org. Chem. 2014, 10, 2414–2420, doi:10.3762/bjoc.10.251

• conditions [(i) ΜeOH, Pd/C, H2, (ii) ΜeOH, formic acid, Pd/C, H2, (iii) ΜeOH, acetic acid, Pd/C, H2, (iv) ΜeOH, trifluoroacetic acid, Pd/C, H2]. A successful alternative was subsequently adopted comprising the linking of 4 to δ-azidolevulinic acid (8) (Scheme 2). The latter, having the nucleophilicity of the

Expanding the scope of cyclopropene reporters for the detection of metabolically engineered glycoproteins by Diels–Alder reactions

• Anne-Katrin Späte,
• Verena F. Schart,
• Julia Häfner,
• Andrea Niederwieser,
• Thomas U. Mayer and
• Valentin Wittmann

Beilstein J. Org. Chem. 2014, 10, 2235–2242, doi:10.3762/bjoc.10.232

• min–1; mobile phase: gradient of acetonitrile with 0.1% formic acid (solvent A) in water with 0.1% formic acid (solvent B). Microscopy was performed using a point laser scanning confocal microscope Zeiss LSM 510 Meta equipped with a Meta detector for spectral imaging. The synthesis of 1 and 2 was