Synthesis of N-phenyl- and N-thiazolyl-1H-indazoles by copper-catalyzed intramolecular N-arylation of ortho-chlorinated arylhydrazones

• Yara Cristina Marchioro Barbosa,
• Guilherme Caneppele Paveglio,
• Claudio Martin Pereira de Pereira,
• Sidnei Moura,
• Cristiane Storck Schwalm,
• Gleison Antonio Casagrande and
• Lucas Pizzuti

Beilstein J. Org. Chem. 2022, 18, 1079–1087, doi:10.3762/bjoc.18.110

• electrospray ionization (ESI) source (MicrOTOF-QII, Bruker Scientific) in positive mode. The compounds were individually dissolved in a solution of 50% chromatographic grade MeCN and 50% deionized H2O + 0.1% formic acid. General experimental procedure for the synthesis of hydrazones 1a–i In a 100 mL round

A versatile way for the synthesis of monomethylamines by reduction of N-substituted carbonylimidazoles with the NaBH₄/I₂ system

• Lin Chen,
• Xuan Zhou,
• Zhiyong Chen,
• Changxu Wang,
• Shunjie Wang and
• Hanbing Teng

Beilstein J. Org. Chem. 2022, 18, 1032–1039, doi:10.3762/bjoc.18.104

• the methylation reagents and the reductive amination reactions by using formaldehyde or paraformaldehyde as the “indirect” alkylation reagents [16][17][18][19]. Recently, a variety of promising methylating agents or C1 sources such as formic acid [20][21], methanol [22][23][24][25][26][27][28][29][30

Synthesis of odorants in flow and their applications in perfumery

• Merlin Kleoff,
• Paul Kiler and
• Philipp Heretsch

Beilstein J. Org. Chem. 2022, 18, 754–768, doi:10.3762/bjoc.18.76

• safe two-step synthesis of 56 from cyclohexanone. In the first step, a solution of cyclohexanone in dodecane is mixed in a Q-piece with hydrogen peroxide, nitric acid, and formic acid and subsequently pumped at room temperature through a PTFE tube reactor with a residence time of 93 min. The resulting

Identification of the new prenyltransferase Ubi-297 from marine bacteria and elucidation of its substrate specificity

• Jamshid Amiri Moghaddam,
• Huijuan Guo,
• Karsten Willing,
• Thomas Wichard and
• Christine Beemelmanns

Beilstein J. Org. Chem. 2022, 18, 722–731, doi:10.3762/bjoc.18.72

• appropriate fraction was collected, evaporated, and purified by preparative HPLC (Shimadzu) over a phenyl-hexyl column (Luna, 5 µm, 250 × 21.2 mm, 100 Å) (eluent: H2O/MeCN + 0.1% formic acid 80:20 to 50:50). The appropriate fraction was collected and evaporated to afford farnesylated 8-HQA. HRMS/MS analysis

• °C using a Luna Omega C18 column (100 × 2.1 mm, 1.6 μm, 100 Å, Phenomenex) preceded by a SecurityGuardTM ULTRA guard cartridge (2 × 2.1 mm, Phenomenex). Mobile phases were acidified with 0.1% formic acid and consisted of H2O (A), and acetonitrile (B) with a flow rate of 0.3 mL/min and the injection

Inductive heating and flow chemistry – a perfect synergy of emerging enabling technologies

• Conrad Kuhwald,
• Sibel Türkhan and
• Andreas Kirschning

Beilstein J. Org. Chem. 2022, 18, 688–706, doi:10.3762/bjoc.18.70

• ) [93]. Cyclohexanone (25) was mixed with conc. formic acid, and a mixture of H2O2 (30%)/HNO3 (65%) in a PTFE reactor at rt. This led to the formation of the cyclic triperoxide 91 in 48% (isolated) yield. Interestingly, the equilibrium favors the formation of the trimer 91 over the corresponding dimeric

Terpenoids from Glechoma hederacea var. longituba and their biological activities

• Dong Hyun Kim,
• Song Lim Ham,
• Zahra Khan,
• Sun Yeou Kim,
• Sang Un Choi,
• Chung Sub Kim and
• Kang Ro Lee

Beilstein J. Org. Chem. 2022, 18, 555–566, doi:10.3762/bjoc.18.58

• . The monosaccharide of 5 was detected at 13.8 min, the same detection time (13.8 min) as ᴅ-glucopyranoside. LC–MS analysis was perfomed under the following conditions: flow rate 0.7 mL/min; 25% MeCN with 0.1% formic acid, column, Kinetex C18 column (250 mm × 4.6 mm, 5 µm, Phenomenex). Sugar analysis

Synthesis of a new water-soluble hexacarboxylated tribenzotriquinacene derivative and its competitive host–guest interaction for drug delivery

• Man-Ping Li,
• Nan Yang and
• Wen-Rong Xu

Beilstein J. Org. Chem. 2022, 18, 539–548, doi:10.3762/bjoc.18.56

• 90% acetonitrile with 0.1% formic acid and 10% water with 0.1% formic acid at a flow rate of 0.4 mL/min. Freeze-drying was conducted on a Scientz-18N freeze-dryer. Synthesis of compound 2. A mixture of compound 1 (2.30 g, 3.7 mmol), ethyl azidoacetate (5.76 g, 44.7 mmol), copper(II) sulfate

Synthetic strategies toward 1,3-oxathiolane nucleoside analogues

• Umesh P. Aher,
• Dhananjai Srivastava,
• Girij P. Singh and
• Jayashree B. S

Beilstein J. Org. Chem. 2021, 17, 2680–2715, doi:10.3762/bjoc.17.182

• ammonolysis in methanol affords compound 1c. The silylation of 1c with TBDPSCl was carried out, and then coupling reaction with tert-Boc-Met-Leu-Phe-OH in the presence of DCC and HOBt provided compound 98. The tert-Boc protecting group was further removed in formic acid, and the resulting nucleoside peptide

Recent advances in the tandem annulation of 1,3-enynes to functionalized pyridine and pyrrole derivatives

• Yi Liu,
• Puying Luo,
• Yang Fu,
• Tianxin Hao,
• Xuan Liu,
• Qiuping Ding and
• Yiyuan Peng

Beilstein J. Org. Chem. 2021, 17, 2462–2476, doi:10.3762/bjoc.17.163

• pyrrole derivatives: i) Knorr reaction: the condensation of α-aminoketones or α-amino esters in the presence of zinc powder and sodium acetate; ii) Paal–Knorr reaction: the condensation of 1,4-dicarbonyl compounds and amines, catalyzed by formic acid in anhydrous alcohol; iii) Hantzsch reaction: the

Advances in mercury(II)-salt-mediated cyclization reactions of unsaturated bonds

• Sumana Mandal,
• Raju D. Chaudhari and
• Goutam Biswas

Beilstein J. Org. Chem. 2021, 17, 2348–2376, doi:10.3762/bjoc.17.153

• materials. For example, Zhang et al. showed that refluxing anilide 177 in presence of a catalytic amount of Hg(OAc)2 and 90% formic acid gave the tricyclic heterocyclic scaffold 178 [113]. It involved a two-step process with the rearrangement of the primary cyclization products (Scheme 53). In 2013, Lin et

Development of N-F fluorinating agents and their fluorinations: Historical perspective

• Teruo Umemoto,
• Yuhao Yang and
• Gerald B. Hammond

Beilstein J. Org. Chem. 2021, 17, 1752–1813, doi:10.3762/bjoc.17.123

• acid, or its metal salt in acetonitrile or as a 50:1 mixture of acetonitrile/formic acid at −40 to 0 °C. The yields were good to excellent [86] (Figure 7). The trimer 24-3 and polymer homologues 24-4 were also prepared. The N,N’-difluorobipyridinium salts are stable and generally furnished non

Analogs of the carotane antibiotic fulvoferruginin from submerged cultures of a Thai Marasmius sp.

• Birthe Sandargo,
• Leon Kaysan,
• Rémy B. Teponno,
• Christian Richter,
• Benjarong Thongbai,
• Frank Surup and
• Marc Stadler

Beilstein J. Org. Chem. 2021, 17, 1385–1391, doi:10.3762/bjoc.17.97

• , Bruker, Bremen, Germany) [column 2.1 × 50 mm, 1.7 µm, C18 Acquity UPLC BEH (Waters, Eschborn, Germany)], with deionized water + 0.1% formic acid (solvent A) as well as acetonitrile + 0.1% formic acid (solvent B) and a gradient of 5% B for 0.5 min increasing to 100% B in 19.5 min, maintaining 100% B for 5

• (Phenomenex, Inc., Aschaffenburg, Germany) and subsequently pre-fractionated utilizing RP-HPLC with a Gilson PLC 2250 purification system (Middleton, WI, USA) and a VP Nucleodur 100-5 C18 ec 250 × 40 mm, 7 µm column (Macherey-Nagel, Düren, Germany). Acetonitrile + 0.1% formic acid and deionized water + 0.1

Chemical constituents of Chaenomeles sinensis twigs and their biological activity

• Joon Min Cha,
• Dong Hyun Kim,
• Lalita Subedi,
• Zahra Khan,
• Sang Un Choi,
• Sun Yeou Kim and
• Chung Sub Kim

Beilstein J. Org. Chem. 2020, 16, 3078–3085, doi:10.3762/bjoc.16.257

• was subjected without purification to LC–MS analysis (0.7 mL/min; 25% aqueous CH3CN with 0.1% formic acid for 30 min). The authentic samples of ᴅ-glucopyranose and ʟ-glucopyranose were derivatized and analyzed by the same method as described above. The hydrolysate derivative of compound 1 was detected

Semiautomated glycoproteomics data analysis workflow for maximized glycopeptide identification and reliable quantification

• Steffen Lippold,
• Arnoud H. de Ru,
• Jan Nouta,
• Peter A. van Veelen,
• Magnus Palmblad,
• Manfred Wuhrer and
• Noortje de Haan

Beilstein J. Org. Chem. 2020, 16, 3038–3051, doi:10.3762/bjoc.16.253

• File 2) but may occur at the peptide portion as well [24][25][26]. Formylation is likely introduced by the exposure of the tryptic peptides to formic acid during the acid precipitation of sodium deoxycholate in the final step of the sample preparation and during subsequent storage [24]. Within the

• agitation, the beads were washed three times with PBS and three times with water. The immunoglobulins were released by acid elution (100 mM formic acid) and collected into a 96-well PCR plate (Greiner Bio-One, Kremsmünster, Austria). Finally, the eluates were dried for 2.5 h at 60 °C by centrifugation under

• to room temperature. Tryptic digestion was started by the addition of 50 µL digestion buffer containing 50 mM ammonium bicarbonate pH 8.5 and 200 ng sequencing-grade trypsin. Upon mixing for 5 min, the sample was incubated at 37 °C overnight. Acid precipitation using 1.2 µL formic acid was performed

Clustering and curation of electropherograms: an efficient method for analyzing large cohorts of capillary electrophoresis glycomic profiles for bioprocessing operations

• Ian Walsh,
• Matthew S. F. Choo,
• Sim Lyn Chiin,
• Amelia Mak,
• Shi Jie Tay,
• Pauline M. Rudd,
• Yang Yuansheng,
• Andre Choo,
• Ho Ying Swan and
• Terry Nguyen-Khuong

Beilstein J. Org. Chem. 2020, 16, 2087–2099, doi:10.3762/bjoc.16.176

• of the RFMS-labelled glycans was performed using a 96-well GlycoWorks HILIC μElution Plate (Waters Corp). The plate was initially equilibrated with sequential washes with dH2O and 85% ACN. The samples were loaded onto the wells and washed with 90% ACN/1% formic acid (FA). The glycans were eluted with

Syntheses of spliceostatins and thailanstatins: a review

• William A. Donaldson

Beilstein J. Org. Chem. 2020, 16, 1991–2006, doi:10.3762/bjoc.16.166

• -butyl esters with formic acid gave the carboxylic acid 9, 7, or 5. Additionally, the treatment of the thailanstatin A tert-butyl ester with lithium chloride generated the thailanstatin B tert-butyl ester. Ghosh used a similar cross-metathesis/Suzuki–Miyaura coupling sequence for the preparation of

One-pot synthesis of isosorbide from cellulose or lignocellulosic biomass: a challenge?

• Isaline Bonnin,
• Raphaël Mereau,
• Thierry Tassaing and
• Karine De Oliveira Vigier

Beilstein J. Org. Chem. 2020, 16, 1713–1721, doi:10.3762/bjoc.16.143

• 1.5 h in an ethanol/water (50:50) mixture at 210 °C, and ii) CIMV (Compagnie Industrielle de la Matière Végétale) technology, where wheat straw was treated during 3.5 h of acetic acid/formic acid/water (50:30:15 m/m/m) extraction at 105 °C and then in the presence of H2O2 and organic acids (peracetic

A dynamic combinatorial library for biomimetic recognition of dipeptides in water

• Florian Klepel and
• Bart Jan Ravoo

Beilstein J. Org. Chem. 2020, 16, 1588–1595, doi:10.3762/bjoc.16.131

• stirring overnight (100 rpm), the samples were acidified with a 5% solution of formic acid in water. The samples were diluted 1:10 with water and measured with HPLC–MS setup I. HPLC–MS measurements The HPLC setup was based on a Shimadzu system and consisted of a CBM-20A controller, a SIL-HTA auto sampler

Synthesis of 3-substituted isoxazolidin-4-ols using hydroboration–oxidation reactions of 4,5-unsubstituted 2,3-dihydroisoxazoles

• Lívia Dikošová,
• Júlia Laceková,
• Ondrej Záborský and
• Róbert Fischer

Beilstein J. Org. Chem. 2020, 16, 1313–1319, doi:10.3762/bjoc.16.112

• (Scheme 4). According to the literature, the N-debenzylation by a Pd-catalyzed hydrogenolysis in methanol with formic acid as the hydrogen source [37][38] should allow the access to N-deprotected isoxazolidines. Unfortunately, all attempts to remove the benzyl group directly from the model isoxazolidine

Design and synthesis of diazine-based panobinostat analogues for HDAC8 inhibition

• Sivaraman Balasubramaniam,
• Sajith Vijayan,
• Liam V. Goldman,
• Xavier A. May,
• Kyra Dodson,
• Sweta Adhikari,
• Fatima Rivas,
• Davita L. Watkins and
• Shana V. Stoddard

Beilstein J. Org. Chem. 2020, 16, 628–637, doi:10.3762/bjoc.16.59

• an ESI–TOF mass spectrometer (Agilent 6220 Time-of-Flight), gas temperature – 350 °C, drying gas (N2) – 8.0 L/min, mobile phase(s): methanol with 0.1% formic acid, flow rate: 0.2 mL/min, sample preparation: The sample was dissolved in 1 drop of chloroform and diluted with 1 mL methanol. Additional

A systematic review on silica-, carbon-, and magnetic materials-supported copper species as efficient heterogeneous nanocatalysts in “click” reactions

• Pezhman Shiri and
• Jasem Aboonajmi

Beilstein J. Org. Chem. 2020, 16, 551–586, doi:10.3762/bjoc.16.52

• dispersed in triethylorthoformate and some drops of formic acid were added. The mixture was heated at reflux for 20 h to receive the new functionalized nanoparticles 103. The nanoparticles 103 were dispersed in 1,6-diisopropylaniline (104) by ultrasonication. The mixture was heated at 120 °C for about 20 h

Architecture and synthesis of P,N-heterocyclic phosphine ligands

• Wisdom A. Munzeiwa,
• Bernard Omondi and
• Vincent O. Nyamori

Beilstein J. Org. Chem. 2020, 16, 362–383, doi:10.3762/bjoc.16.35

• treated with triflic anhydride to afford the corresponding triflate 55. Microwave-assisted reduction of compound 55 with pyridinium chloride afforded the α-chloropyridine derivative 56, which was further catalytically dehalogenated with palladium on carbon and formic acid to generate the pyridine scaffold

Palladium-catalyzed Sonogashira coupling reactions in γ-valerolactone-based ionic liquids

• László Orha,
• József M. Tukacs,
• László Kollár and
• László T. Mika

Beilstein J. Org. Chem. 2019, 15, 2907–2913, doi:10.3762/bjoc.15.284

• mixture containing 0.1% (v/v) formic acid. Solutions were directly introduced into the ion source using a syringe pump. Under the applied conditions, the compounds form protonated molecules, [M + H]+ in positive ionization mode (ESI). Detailed experimental procedures, characterization data are reported in

Skeletocutins M–Q: biologically active compounds from the fruiting bodies of the basidiomycete Skeletocutis sp. collected in Africa

• Tian Cheng,
• Clara Chepkirui,
• Cony Decock,
• Josphat C. Matasyoh and
• Marc Stadler

Beilstein J. Org. Chem. 2019, 15, 2782–2789, doi:10.3762/bjoc.15.270

• , solvent A: H2O + 0.1% formic acid, solvent B: acetonitrile + 0.1% formic acid, elution gradient: 5% solvent B for 0.5 min, increasing solvent B to 100% within 19.5 min, 100% solvent B for 5 min, flow rate: 0.6 mL/min, UV–vis detection at λ = 200–600 nm) and ESI–TOF–MS analysis (maXis™ system, Bruker, scan

Bipolenins K–N: New sesquiterpenoids from the fungal plant pathogen Bipolaris sorokiniana

• Chin-Soon Phan,
• Hang Li,
• Simon Kessler,
• Peter S. Solomon,
• Andrew M. Piggott and
• Yit-Heng Chooi

Beilstein J. Org. Chem. 2019, 15, 2020–2028, doi:10.3762/bjoc.15.198

• 200–800 nm, gradient: 0–10 min 5–95% MeCN with 0.1% formic acid, 10–15 min 95% MeCN with 0.1% formic acid) eluted 1 (tR 5.10 min), 2 (tR 4.79 min), 3 (tR 5.28 min), 4 (tR 5.96 min), 5 (tR 7.64 min), 6 (tR 6.00 min), 7 (tR 6.45 min), 8 (tR 4.85 min), 9 (tR 5.69 min), 10 (tR 6.37 min), 11 (tR 6.48 min