A chiral self-sorting photoresponsive coordination cage based on overcrowded alkenes

• Constantin Stuckhardt,
• Diederik Roke,
• Wojciech Danowski,
• Edwin Otten,
• Sander J. Wezenberg and
• Ben L. Feringa

Beilstein J. Org. Chem. 2019, 15, 2767–2773, doi:10.3762/bjoc.15.268

• by using the Stokes–Einstein equation [54]. By means of ESI high-resolution mass spectrometry, we were able to verify the Pd2L4 constitution of both cages. The HRMS spectrum of Pd2(stable Z-1)4 shows the signals for the cations [Pd2(stable Z-1)4(NO3)3]+, [Pd2(stable Z-1)4(NO3)2]2+, [Pd2(stable Z-1)4

Fluorinated maleimide-substituted porphyrins and chlorins: synthesis and characterization

• Valentina A. Ol’shevskaya,
• Elena G. Kononova and
• Andrei V. Zaitsev

Beilstein J. Org. Chem. 2019, 15, 2704–2709, doi:10.3762/bjoc.15.263

• ) or Ni(II) with N-propargylmaleimide via the CuAAC click reaction to afford fluorinated porphyrin–triazole–maleimide conjugates. New maleimide derivatives were isolated in reasonable yields and identified by UV–vis, 1H NMR, 19F NMR spectroscopy and mass-spectrometry. Keywords: chlorin; maleimide

• spectroscopy and mass spectrometry. These novel porphyrins and chlorins are expected to be efficient photosensitizers for cancer treatment. The presence of four maleimide groups in these compounds may provide improved binding with proteins in living systems. Synthesis of fluorinated maleimide-substituted

Acid-catalyzed rearrangements in arenes: interconversions in the quaterphenyl series

• Sarah L. Skraba-Joiner,
• Carter J. Holt and
• Richard P. Johnson

Beilstein J. Org. Chem. 2019, 15, 2655–2663, doi:10.3762/bjoc.15.258

• through time-of-flight matrix assisted laser desorption ionization (MALDI–TOF–MS) mass spectrometry, using sulfur as a matrix. Suzuki–Miyaura coupling to form m,p’-quaterphenyl (13) [35]: 4-Biphenylboronic acid (0.18 g, 0.91 mmol) and 1 M K2CO3 (1.5 mL) were added to a 10 mL Pyrex microwave tube. 3

Nanangenines: drimane sesquiterpenoids as the dominant metabolite cohort of a novel Australian fungus, Aspergillus nanangensis

• Heather J. Lacey,
• Cameron L. M. Gilchrist,
• Andrew Crombie,
• John A. Kalaitzis,
• Daniel Vuong,
• Peter J. Rutledge,
• Peter Turner,
• John I. Pitt,
• Ernest Lacey,
• Yit-Heng Chooi and
• Andrew M. Piggott

Beilstein J. Org. Chem. 2019, 15, 2631–2643, doi:10.3762/bjoc.15.256

• -resolution positive electrospray ionisation mass spectrometry (HRESI(+)MS) analysis of nanangenine A (1) revealed an adduct ion ([M + Na]+ m/z 305.1363) indicative of a molecular formula C15H22O5 requiring five double bond equivalents (DBE). No distinguishing absorption maxima were observed in the UV–vis

Synthesis of novel sulfide-based cyclic peptidomimetic analogues to solonamides

• José Brango-Vanegas,
• Luan A. Martinho,
• Lucinda J. Bessa,
• Andreanne G. Vasconcelos,
• Alexandra Plácido,
• Alex L. Pereira,
• José R. S. A. Leite and
• Angelo H. L. Machado

Beilstein J. Org. Chem. 2019, 15, 2544–2551, doi:10.3762/bjoc.15.247

• sulfhydryl group to the electrophilic MBH residue. Spectral characterization of the chemical structures of the solonamide analogues 9 The compounds were characterized by one- and two-dimensional NMR spectroscopy, infrared spectroscopy (IR) and mass spectrometry. The high-resolution MS/MS analysis allowed the

Formation of alkyne-bridged ferrocenophanes using ring-closing alkyne metathesis on 1,1’-diacetylenic ferrocenes

• Celine Bittner,
• Dirk Bockfeld and
• Matthias Tamm

Beilstein J. Org. Chem. 2019, 15, 2534–2543, doi:10.3762/bjoc.15.246

• performed RCAM with a higher substrate concentration of 1a of 21 mM. When further increasing the concentration of 1a to 125 mM a product mixture of the monomeric ferrocenophane 2a, the fully ring-closed dimeric compound as well as the open dimer can be identified with the help of mass spectrometry (see also

• conversion of 1b could be achieved in the metathesis reaction after 4 hours as the signal for the terminal proton cannot be observed anymore in the 1H NMR spectrum. With the aid of mass spectrometry, the two species could be assigned as the monomeric ferrocenophane 2b as well as its fully ring-closed dimeric

Anion-driven encapsulation of cationic guests inside pyridine[4]arene dimers

• Anniina Kiesilä,
• Jani O. Moilanen,
• Anneli Kruve,
• Christoph A. Schalley,
• Perdita Barran and
• Elina Kalenius

Beilstein J. Org. Chem. 2019, 15, 2486–2492, doi:10.3762/bjoc.15.241

• Berlin, Germany Michael Barber Centre for Collaborative Mass Spectrometry, Manchester Institute of Biotechnology, School of Chemistry, The University of Manchester, Princess Street, Manchester, UK 10.3762/bjoc.15.241 Abstract Pyridine[4]arenes have previously been considered as anion binding hosts due

• in pyridine[4]arene is an anion-driven process. Keywords: cation binding; DFT calculations; ion mobility mass spectrometry; macrocycles; pyridinearenes; resorcinarenes; Introduction Resorcinarenes and their derivatives are known for the molecular recognition properties of their self-assembled

• capsules were originally assumed to encapsulate anionic guests inside their cavity due to the π-acidic character of the aromatic walls [7][8]. Mattey et al. detected 1:1 complex formation with PF6− and BF4− by mass spectrometry, however, without ion mobility mass spectrometry, the location of the anion

Indium-mediated C-allylation of melibiose

• Christian Denner,
• Manuel Gintner,
• Hanspeter Kählig and
• Walther Schmid

Beilstein J. Org. Chem. 2019, 15, 2458–2464, doi:10.3762/bjoc.15.238

• information file of compound 2-syn. Acknowledgements We would like to thank the NMR center for NMR analysis, the mass spectrometry center for mass analysis and A. Roller for X-ray crystallographic analysis. We also thank T. Wrodnigg for critical comments on the manuscript.

Photochromic diarylethene ligands featuring 2-(imidazol-2-yl)pyridine coordination site and their iron(II) complexes

• Andrey G. Lvov,
• Max Mörtel,
• Anton V. Yadykov,
• Frank W. Heinemann,
• Valerii Z. Shirinian and
• Marat M. Khusniyarov

Beilstein J. Org. Chem. 2019, 15, 2428–2437, doi:10.3762/bjoc.15.235

• successfully applied for the synthesis of a new family of photochromic ligands. The structures of the synthesized diarylethene-based ligands 3, 4, 6, and 7 were confirmed by 1H and 13C NMR spectroscopy and mass spectrometry. The molecular structure of 6 was additionally confirmed by X-ray crystallography. In

Effect of ring size on photoisomerization properties of stiff stilbene macrocycles

• Sandra Olsson,
• Óscar Benito Pérez,
• Magnus Blom and
• Adolf Gogoll

Beilstein J. Org. Chem. 2019, 15, 2408–2418, doi:10.3762/bjoc.15.233

• by the Swedish National Infrastructure for Computing (SNIC) at National Supercomputer Centre (NSC), Linköping University. We are indebted to Dr. Lisa Haigh, Imperial College London, Department of Chemistry, Mass spectrometry service, for the HRMS analyses.

Harnessing enzyme plasticity for the synthesis of oxygenated sesquiterpenoids

• Melodi Demiray,
• David J. Miller and
• Rudolf K. Allemann

Beilstein J. Org. Chem. 2019, 15, 2184–2190, doi:10.3762/bjoc.15.215

• this work and of Dr. Rob Jenkins and Mr Thomas Williams with mass spectrometry and NMR spectroscopy is gratefully acknowledged. This work forms part of the Ph.D. project carried out by Dr. Melodi Demiray and is contained within her Ph.D. Thesis (Cardiff University, 2017) and was supported by the UK

Synthesis and properties of sulfur-functionalized triarylmethylium, acridinium and triangulenium dyes

• Marco Santella,
• Eduardo Della Pia,
• Jakob Kryger Sørensen and
• Bo W. Laursen

Beilstein J. Org. Chem. 2019, 15, 2133–2141, doi:10.3762/bjoc.15.210

• ). These conditions consisted of heating the reaction components in refluxing acetonitrile in the presence of collidine as base. For all three carbenium salts examinations showed that only ethanethiol lead to substitution. The progress of the reaction was conveniently followed by MALDI–TOF mass

• spectrometry. In case of the reactions with tert-butylthiolate, neither detection of the target molecule nor any of the intermediates were observed. This lack of reactivity is likely explained by the tert-butylthiolate nucleophile being too bulky to undergo reaction. In the successful reactions, which had

Multiple threading of a triple-calix[6]arene host

• Veronica Iuliano,
• Roberta Ciao,
• Emanuele Vignola,
• Carmen Talotta,
• Patrizia Iannece,
• Margherita De Rosa,
• Annunziata Soriente,
• Carmine Gaeta and
• Placido Neri

Beilstein J. Org. Chem. 2019, 15, 2092–2104, doi:10.3762/bjoc.15.207

• axle 7+ was studied by HR-ESI-FT-ICR mass spectrometry and 1D/2D NMR (Figure 3). A 1:1 mixture of 6 and 7+·TFPB− in CHCl3 was stirred at 298 K for 15 min, until the solution was clarified, and then used for mass spectrometry analysis. An ESI-FT-ICR mass spectrum of this solution (Figure 3, bottom

Characterization of two new degradation products of atorvastatin calcium formed upon treatment with strong acids

• Jürgen Krauß,
• Monika Klimt,
• Markus Luber,
• Peter Mayer and
• Franz Bracher

Beilstein J. Org. Chem. 2019, 15, 2085–2091, doi:10.3762/bjoc.15.206

• concentrated sulfuric acid, lactonization/dehydration is accompanied by complete loss of the carboxanilide residue to give pyrrole 7. Complete one-step removal of carboxamide residues from aromatic rings has been observed before in investigations of fragmentations of protonated species in mass spectrometry [21

α-Photooxygenation of chiral aldehydes with singlet oxygen

• Dominika J. Walaszek,
• Magdalena Jawiczuk,
• Jakub Durka,
• Olga Drapała and
• Dorota Gryko

Beilstein J. Org. Chem. 2019, 15, 2076–2084, doi:10.3762/bjoc.15.205

• chemical shifts (δ) and coupling constants (J) are expressed in ppm and Hertz, respectively. High-resolution mass spectrometry (HRMS) data were obtained at the Synapt G2-S HDMS mass spectrometer equipped with an electrospray ion source and q-TOF type mass analyzer. Specific rotation was measured on a JASCO

Genome mining in Trichoderma viride J1-030: discovery and identification of novel sesquiterpene synthase and its products

• Xiang Sun,
• You-Sheng Cai,
• Yujie Yuan,
• Guangkai Bian,
• Ziling Ye,
• Zixin Deng and
• Tiangang Liu

Beilstein J. Org. Chem. 2019, 15, 2052–2058, doi:10.3762/bjoc.15.202

• construct the plasmid pXS222. Next, pXS222 was transformed into BL21 to overexpress and purify Tvi09626 (Figure S2, Supporting Information File 1). The substrates GPP, FPP and GGPP were incubated with the protein individually and the products were detected and analysed by gas chromatography/mass

• spectrometry (GC–MS) [30][34]. In vitro assays clearly showed that Tvi09626 could use FPP as its only substrate to produce compound 1 (Figure 3 and Figure S3, Supporting Information File 1). Heterologous expression of Tvi09626 in S. cerevisiae To further verify the function of the putative terpene synthase, a

Isolation and characterisation of irinans, androstane-type withanolides from Physalis peruviana L.

• Annika Stein,
• Dave Compera,
• Bianka Karge,
• Mark Brönstrup and
• Jakob Franke

Beilstein J. Org. Chem. 2019, 15, 2003–2012, doi:10.3762/bjoc.15.196

• , Waters 2424 ELS detector, and a Waters SQ Detector 2 for mass spectrometry in ESI+ and ESI– modes between m/z 150 and 1000. In analytical mode, a Phenomenex Kinetex column (2.6 µm, C18, 100 Å, 4.6 × 100 mm) was used with a gradient of [solvent A: H2O + 0.05% formic acid; solvent B: acetonitrile + 0.045

Attempted synthesis of a meta-metalated calix[4]arene

• Christopher D. Jurisch and
• Gareth E. Arnott

Beilstein J. Org. Chem. 2019, 15, 1996–2002, doi:10.3762/bjoc.15.195

• strategy involved using a mesoionic carbene to direct C–H activation, but proved to form an unexpectedly unstable intermediate that was identified through high-resolution mass spectrometry. On route to our target, a new optimized method to mononitrocalix[4]arenes was developed, including optimized and high

Synthesis and anion binding properties of phthalimide-containing corona[6]arenes

• Meng-Di Gu,
• Yao Lu and
• Mei-Xiang Wang

Beilstein J. Org. Chem. 2019, 15, 1976–1983, doi:10.3762/bjoc.15.193

• investigate their anion binding behaviour. Taking compound 3a as a representative, we examined the interaction of macrocycles 3 with anions of tetra-n-butylammonium salts by means of electron spray ionization (ESI) mass spectrometry. It was found that the mass spectra of mixed samples of 3a with n-Bu4NX gave

Analysis of sesquiterpene hydrocarbons in grape berry exocarp (Vitis vinifera L.) using in vivo-labeling and comprehensive two-dimensional gas chromatography–mass spectrometry (GC×GC–MS)

• Philipp P. Könen and
• Matthias Wüst

Beilstein J. Org. Chem. 2019, 15, 1945–1961, doi:10.3762/bjoc.15.190

• chromatograms, i.e., compounds of common structure classes are grouped. The coupling of comprehensive two-dimensional gas chromatography with mass spectrometry as the “third dimension” also provides important information for substance identification. The combination of these advantages makes the GC×GC one of

• of d6-α-cubebene could be confirmed by mass spectrometry as the isotopologue with the highest, possible incorporation of deuterium when d2-DOX was used as a precursor. The molecular ion peak [M]+• of d6-α-cubebene therefore has a mass-to-charge ratio of 210. The abstraction of a single deuterated

Morphology-tunable and pH-responsive supramolecular self-assemblies based on AB₂-type host–guest-conjugated amphiphilic molecules for controlled drug delivery

• Yang Bai,
• Cai-ping Liu,
• Di Chen,
• Long-hai Zhuo,
• Huai-tian Bu and
• Wei Tian

Beilstein J. Org. Chem. 2019, 15, 1925–1932, doi:10.3762/bjoc.15.188

• –3.9, 4.3–4.9 and 5.6–5.9 and protons of BM at δ = 7.0–8.4 could be observed obviously in the 1H NMR spectrum of β-CD-BM2 (Figure S1B-d, Supporting Information File 1). Furthermore, the molecular weight of β-CD-BM2 (Figure S1C, Supporting Information File 1) measured by high-resolution mass

• spectrometry was 1497.5266 [M + H+], which was in accordance with the theoretical value of 1496.5236. On the basis of the above results, AB2-type host–guest-conjugated amphiphilic monomer β-CD-BM2 has been successfully synthesized. Supramolecular self-assembly behavior of β-CD-BM2 The morphology of the self

Synthesis of a [6]rotaxane with singly threaded γ-cyclodextrins as a single stereoisomer

• Jason Yin Hei Man and
• Ho Yu Au-Yeung

Beilstein J. Org. Chem. 2019, 15, 1829–1837, doi:10.3762/bjoc.15.177

• HKU Foundation Postgraduate Fellowship. We acknowledge UGC funding administered by The University of Hong Kong for support of the Electrospray Ionization Quadrupole Time-of-Flight Mass Spectrometry Facilities under support for Interdisciplinary Research in Chemical Science.

Complexation of 2,6-helic[6]arene and its derivatives with 1,1′-dimethyl-4,4′-bipyridinium salts and protonated 4,4'-bipyridinium salts: an acid–base controllable complexation

• Jing Li,
• Qiang Shi,
• Ying Han and
• Chuan-Feng Chen

Beilstein J. Org. Chem. 2019, 15, 1795–1804, doi:10.3762/bjoc.15.173

• reaction of 4,4′-bipyridine with concentrated HCl in acetonitrile followed by counteranion exchange with sodium tetrakis[3,5-di(trifluoromethyl)phenyl]borate (NaBArF) in dichloromethane. The new compounds were confirmed by NMR spectroscopy and high-resolution mass spectrometry (Supporting Information File

Synthesis, enantioseparation and photophysical properties of planar-chiral pillar[5]arene derivatives bearing fluorophore fragments

• Guojuan Li,
• Chunying Fan,
• Guo Cheng,
• Wanhua Wu and
• Cheng Yang

Beilstein J. Org. Chem. 2019, 15, 1601–1611, doi:10.3762/bjoc.15.164

• -resolution mass spectrometry (HRMS, Supporting Information File 1, Figures S19–S21). Photophysical properties The photophysical properties were investigted by UV–vis absorption and fluorescence spectroscopy, as well as through fluorescence decay measurements. As shown in Figure 1a, the UV–vis spectrum of P5A

Synthesis of 9-O-arylated berberines via copper-catalyzed C_Ar–O coupling reactions

• Qiaoqiao Teng,
• Xinhui Zhu,
• Qianqian Guo,
• Weihua Jiang,
• Jiang Liu and
• Qi Meng

Beilstein J. Org. Chem. 2019, 15, 1575–1580, doi:10.3762/bjoc.15.161

• products was firstly indicated by mass spectrometry (ESIMS), in which the respective [M − I]+ signal was observed as the base peak. The NMR spectra resembled those of BBR, with the methylene protons resonating as triplets in the range of 5.00–3.00 ppm. Only one rotamer was observed in the 1H NMR spectrum