Synthesis and anticancer activity of bis(2-arylimidazo[1,2-a]pyridin-3-yl) selenides and diselenides: the copper-catalyzed tandem C–H selenation of 2-arylimidazo[1,2-a]pyridine with selenium

• Mio Matsumura,
• Tsutomu Takahashi,
• Hikari Yamauchi,
• Shunsuke Sakuma,
• Yukako Hayashi,
• Tadashi Hyodo,
• Tohru Obata,
• Kentaro Yamaguchi,
• Yasuyuki Fujiwara and
• Shuji Yasuike

Beilstein J. Org. Chem. 2020, 16, 1075–1083, doi:10.3762/bjoc.16.94

• mechanisms are currently underway in our group. Biologically active selenides and diselenides having heteroaryl groups. Ortep drawings of 2a (a and b) and 3a (c and d, thermal elipsoids indicate 50% probability). The synthesis of bis(2-arylimidazopyridin-3-yl) diselenides. Reaction conditions: 1 (2 mmol), Se

Synthesis of C₇₀-fragment buckybowls bearing alkoxy substituents

• Yumi Yakiyama,
• Shota Hishikawa and
• Hidehiro Sakurai

Beilstein J. Org. Chem. 2020, 16, 681–690, doi:10.3762/bjoc.16.66

• drawing of the crystallographically independent unit with thermal ellipsoid at 50% probability b) Packing structure viewed from the a axis and c) from the b axis. The dotted lines indicate; blue: π–π, grey: CH···π, red: CH···O interactions. In b) and c), hydrogen atoms which are not engaged in any

• colored ones are aromatic carbons. Crystal structure of 5b. a) ORTEP drawing of the crystallographically independent unit with thermal ellipsoid at 50% probability. b) Packing structure viewed from the b axis and c) from the a axis. The dotted lines indicate; grey: CH···π, red: CH···O interactions. In b

• ) and c), hydrogen atoms which are not engaged in any interactions and the contribution of the one enantiomer are omitted for clarity. Crystal structure of 5c. a) ORTEP drawing of the crystallographically independent unit with thermal ellipsoid at 50% probability b) Packing structure viewed from the b

Direct borylation of terrylene and quaterrylene

• Haruka Kano,
• Keiji Uehara,
• Kyohei Matsuo,
• Hironobu Hayashi,
• Hiroko Yamada and
• Naoki Aratani

Beilstein J. Org. Chem. 2020, 16, 621–627, doi:10.3762/bjoc.16.58

• -bridging oligorylenes, d) bay-alkoxy oligorylenes, and e) tetra-tert-butyl oligorylenes. (Top) Single crystal X-ray structure of TB4. The thermal ellipsoids are scaled at 50% probability. (Bottom) Packing diagram of TB4. The solvent molecules are omitted for clarity. UV–vis absorption and fluorescence

Synthesis of triphenylene-fused phosphole oxides via C–H functionalizations

• Md. Shafiqur Rahman and
• Naohiko Yoshikai

Beilstein J. Org. Chem. 2020, 16, 524–529, doi:10.3762/bjoc.16.48

• benzo[b]phospholes accessible by the three-component assembly hold promise for further explorations inot novel π-extended phosphole derivatives. Examples of functional molecules based on π-extended phospholes. ORTEP drawings of compound 8a (thermal ellipsoids set at 50% probability). a) top view; b

Six-fold C–H borylation of hexa-peri-hexabenzocoronene

• Mai Nagase,
• Kenta Kato,
• Akiko Yagi,
• Yasutomo Segawa and
• Kenichiro Itami

Beilstein J. Org. Chem. 2020, 16, 391–397, doi:10.3762/bjoc.16.37

• 50% probability; all hydrogen atoms and solvent molecules (pentane) are omitted for clarity; gray: carbon; olive green: boron; red: oxygen. (b) Side view of 1. (c) Packing mode of 1. Photophysical properties of 1. (a) UV–vis absorption (solid lines) spectra, fluorescence (dotted line) spectrum

Synthesis and circularly polarized luminescence properties of BINOL-derived bisbenzofuro[2,3-b:3’,2’-e]pyridines (BBZFPys)

• Ryo Takishima,
• Yuji Nishii,
• Tomoaki Hinoue,
• Yoshitane Imai and
• Masahiro Miura

Beilstein J. Org. Chem. 2020, 16, 325–336, doi:10.3762/bjoc.16.32

• × 10−5 M) and in solid states (dispersed in Fomblin®). ORTEP drawings of 4b and 4c with 50% thermal probability. Hydrogen atoms and solvent molecules are omitted for clarity. Only major orientation of the disordered structure is displayed. The CCDC numbers are 1971471 for (R)-4b and 1971470 for (R)-4c

Absolute configurations of talaromycones A and B, α-diversonolic ester, and aspergillusone B from endophytic Talaromyces sp. ECN211

• Ken-ichi Nakashima,
• Junko Tomida,
• Takao Hirai,
• Yoshiaki Kawamura and
• Makoto Inoue

Beilstein J. Org. Chem. 2020, 16, 290–296, doi:10.3762/bjoc.16.28

• been deposited with the Cambridge Crystallographic Data Centre (CCDC 1952663). Structures of compounds 1–6. Key HMBC (blue arrows) and COSY (bold bonds) correlations in 1 and 2. a) ORTEP drawing of 1, with thermal ellipsoids indicating 50% probability. The atoms of the minor disordered component have

• been omitted for clarity. b) Electronic circular dichroism spectra of 1 (black solid line) and 2 (red dashed line). a) ORTEP drawing of 3, with thermal ellipsoids indicating 50% probability. b) Electronic circular dichroism spectra of 3 (black solid line) and 4 (red dashed line). a) ORTEP drawing of 5

• , with thermal ellipsoids indicating 50% probability. b) Electronic circular dichroism spectrum of 5. 1H (400 MHz) and 13C (100 MHz) NMR data for 1 and 2 in CDCl3. Supporting Information Supporting Information File 265: A phytogenic tree for ECN211 and related species and NMR spectra of 1 and 2

Reversible photoswitching of the DNA-binding properties of styrylquinolizinium derivatives through photochromic [2 + 2] cycloaddition and cycloreversion

• Sarah Kölsch,
• Heiko Ihmels,
• Jochen Mattay,
• Norbert Sewald and
• Brian O. Patrick

Beilstein J. Org. Chem. 2020, 16, 111–124, doi:10.3762/bjoc.16.13

• nm in H2O (B). ORTEP drawings of cyclobutane derivatives 4b (A) and 4c (B) in the solid state (thermal ellipsoids indicate 50% probability). The tetrafluoroborate counterions were omitted for clarity. A) Spectrophotometric titration of ct DNA to dimer 4b in BPE buffer (cL = 20 µM, cct DNA = 1.45 mM

SnCl₄-catalyzed solvent-free acetolysis of 2,7-anhydrosialic acid derivatives

• Kesatebrhan Haile Asressu and
• Cheng-Chung Wang

Beilstein J. Org. Chem. 2019, 15, 2990–2999, doi:10.3762/bjoc.15.295

• thiosialoside and sialyl halide donors in order to serve as alternative building blocks for the synthesis of sialic acid-containing glycans. Representative structures of bacterial glycans containing sialic acid. a) ORTEP diagram of compound 4. Thermal ellipsoids indicate 50% probability. b) HMBC spectrum of 6

Two new aromatic polyketides from a sponge-derived Fusarium

• Mada Triandala Sibero,
• Tao Zhou,
• Keisuke Fukaya,
• Daisuke Urabe,
• Ocky K. Karna Radjasa,
• Agus Sabdono,
• Agus Trianto and
• Yasuhiro Igarashi

Beilstein J. Org. Chem. 2019, 15, 2941–2947, doi:10.3762/bjoc.15.289

• , C8, C8a, C9, C10, and C10a) were significantly smaller for structure a than structure b (Table 2). Then, DP4+ was used to quantify this calculated result [25]. DP4+ probability analysis provides reliable guidance on the correct structure among several possible isomers. The developers recommend to use

• the combination of 1H and 13C data for enhancement of DP4+ performance. In this study, the DP4+ probability using only 1H data or only 13C data gave an inconsistent result, but the DP4+ probability using both 1H and 13C data supported the structure a, in which the methoxy group was present at C7, as a

One-pot synthesis of substituted pyrrolo[3,4-b]pyridine-4,5-diones based on the reaction of N-(1-(4-hydroxy-6-methyl-2-oxo-2H-pyran-3-yl)-2-oxo-2-arylethyl)acetamide with amines

• Valeriya G. Melekhina,
• Andrey N. Komogortsev,
• Boris V. Lichitsky,
• Vitaly S. Mityanov,
• Artem N. Fakhrutdinov,
• Arkady A. Dudinov,
• Vasily A. Migulin,
• Yulia V. Nelyubina,
• Elizaveta K. Melnikova and
• Michail M. Krayushkin

Beilstein J. Org. Chem. 2019, 15, 2840–2846, doi:10.3762/bjoc.15.277

• ellipsoids indicate 50% probability. Solvent molecules have been omitted for clarity. General synthetic pathway to 1. Synthesis of acetamides 2. Possible reaction pathways for the formation of enaminone 7. Possible reaction pathways for the formation of pyrrolo[3,4-b]pyridin-5-one derivatives 1. Tautomeric

Synthesis of aryl-substituted thieno[3,2-b]thiophene derivatives and their use for N,S-heterotetracene construction

• Nadezhda S. Demina,
• Nikita A. Kazin,
• Nikolay A. Rasputin,
• Roman A. Irgashev and
• Gennady L. Rusinov

Beilstein J. Org. Chem. 2019, 15, 2678–2683, doi:10.3762/bjoc.15.261

• synthesized in this work. ORTEP diagram for the X-ray structure of compound 7d. Thermal ellipsoids of 50% probability are shown. Synthesis of aryl-substituted TT derivatives 3a–k, product scope, and yields. Synthesis of thieno[3,2-b]thiophen-3(2H)-one 4a–k, product scope, and yields. Synthesis of TTI

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

• sensing. ORTEP diagram of 1a with thermal displacement parameters drawn at 50% probability; hydrogen atoms are omitted for clarity; occupation Fe 74%, Fe’ 26%. Selected bond lengths [Å] and angles [°]: Fe–Ct1 1.6947(12), Fe-Ct11 1.6695(12), Ct1-Fe-Ct11 176.96(8), C9–C10 1.186(11), C8–C9–C10 177.2(9), C19

• –C20 1.165(12), C18–C19–C20 178.1(10). ORTEP diagram of 1b with thermal displacement parameters drawn at 50% probability; hydrogen atoms are omitted for clarity. Selected bond lengths [Å] and angles [°]: Fe–Ct 1.6523(7), Ct–Fe–Ct‘ 180.0, C10–C11 1.127(2), C9–C10–C11 176.3(2). ORTEP diagram of 2a with

• thermal displacement parameters drawn at 50% probability; hydrogen atoms are omitted for clarity. Selected bond lengths [Å] and angles [°]: Fe–Ct 1.6414(6), Ct–Fe–Ct’ 178.809(1), C9–C9‘ 1.193(2), C8–C9–C9‘ 172.1(2). ORTEP diagram of 2b (one of two molecules of the asymmetric unit) with thermal

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

• drawn at the 50% probability level. Variable temperature χT product (blue) and χ (green) of 8 (top) and 9 (bottom) measured at an external magnetic field of 1 T in the heating mode (see Supporting Information File 1 for fitting parameters). Synthesis of photochromic ligands. Reversible photocyclization

In water multicomponent synthesis of low-molecular-mass 4,7-dihydrotetrazolo[1,5-a]pyrimidines

• Irina G. Tkachenko,
• Sergey A. Komykhov,
• Vladimir I. Musatov,
• Svitlana V. Shishkina,
• Viktoriya V. Dyakonenko,
• Vladimir N. Shvets,
• Mikhail V. Diachkov,
• Valentyn A. Chebanov and
• Sergey M. Desenko

Beilstein J. Org. Chem. 2019, 15, 2390–2397, doi:10.3762/bjoc.15.231

• % probability level. Three synthetic approaches to dihydrotetrazolo[1,5-a]pyrimidines. Three-component reaction of 1, 7a,b and 8a–d in water. Three-component reaction of 5-aminotetrazole (1) with formaldehyde (7a) and acetylacetone (10). a) Three-component reaction of 5-aminotetrazole (1) with acetaldehyde (7b

An overview of the cycloaddition chemistry of fulvenes and emerging applications

• Ellen Swan,
• Kirsten Platts and
• Anton Blencowe

Beilstein J. Org. Chem. 2019, 15, 2113–2132, doi:10.3762/bjoc.15.209

• reactive, is prone to dimerization and polymerisation [59][111]. If the reaction is conducted under aqueous conditions, the probability of dimerization has been reported to increase further due to hydrophobic packing of the fulvene molecules [120][121]. Intramolecular cycloadditions Whilst not as widely

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

• probability level. Bottom: Molecular structure of artefact 7 (drawn at the 50% ellipsoid probability level). Separation of atorvastatin (1; retention time: 5.8 min) from the four decomposition products 2 (retention time: 9.2 min), 3 (retention time: 15.6 min), 6 (retention time: 21.4 min) and 7 (retention

Synthesis of benzo[d]imidazo[2,1-b]benzoselenoazoles: Cs₂CO₃-mediated cyclization of 1-(2-bromoaryl)benzimidazoles with selenium

• Mio Matsumura,
• Yuki Kitamura,
• Arisa Yamauchi,
• Yoshitaka Kanazawa,
• Yuki Murata,
• Tadashi Hyodo,
• Kentaro Yamaguchi and
• Shuji Yasuike

Beilstein J. Org. Chem. 2019, 15, 2029–2035, doi:10.3762/bjoc.15.199

• residue was purified by silica gel chromatography (n-hexane/AcOEt). (a) Ortep drawing of 2a (50% probability, only one of two independent molecules is shown) and (b) packing structure. The component based solvent was omitted for clarity. Cs2CO3-mediated cyclization of 1-(2-bromoaryl)imidazoles with Se

Functional panchromatic BODIPY dyes with near-infrared absorption: design, synthesis, characterization and use in dye-sensitized solar cells

• Quentin Huaulmé,
• Cyril Aumaitre,
• Outi Vilhelmiina Kontkanen,
• David Beljonne,
• Alexandra Sutter,
• Gilles Ulrich,
• Renaud Demadrille and
• Nicolas Leclerc

Beilstein J. Org. Chem. 2019, 15, 1758–1768, doi:10.3762/bjoc.15.169

• devices sensitized with BOD-TTPA-alk are slightly higher compared to the ones prepared out of BOD-TTPA. This could be explained by the presence of the alkyl chains on the TPA units that are known to prevent the redox mediator to interact with the TiO2 surface thus reducing the probability to observe a

Recent advances on the transition-metal-catalyzed synthesis of imidazopyridines: an updated coverage

• Gagandeep Kour Reen,
• Ashok Kumar and
• Pratibha Sharma

Beilstein J. Org. Chem. 2019, 15, 1612–1704, doi:10.3762/bjoc.15.165

• aliphatic alkynes gave an optimal yield of the final product in the range of 50–78%. Successful formation of the product on application of 2,2,6,6-tetramethylpiperidine-1-oxyl (TEMPO: a radical scavenger) has nullified the probability of radical pathway. It was thought to be initiated by the coordination of

Transient and intermediate carbocations in ruthenium tetroxide oxidation of saturated rings

• Manuel Pedrón,
• Laura Legnani,
• Maria-Assunta Chiacchio,
• Pierluigi Caramella,
• Tomás Tejero and
• Pedro Merino

Beilstein J. Org. Chem. 2019, 15, 1552–1562, doi:10.3762/bjoc.15.158

• attractors [74], that are the areas in which the probability of finding an electron pair is maximal. Monosynaptic and disynaptic basins correspond to separate atoms and bonds, respectively. When a bond is formed, two monosynaptic basins merge into a new disynaptic basin. The complete ELF analyses of the IRCs

One-pot activation–alkynylation–cyclization synthesis of 1,5-diacyl-5-hydroxypyrazolines in a consecutive three-component fashion

• Christina Görgen,
• Katharina Boden,
• Guido J. Reiss,
• Walter Frank and
• Thomas J. J. Müller

Beilstein J. Org. Chem. 2019, 15, 1360–1370, doi:10.3762/bjoc.15.136

• ) and antibacterial activity (center and right). ORTEP plot of 5-benzoyl-3-phenyl-1H-pyrazole (6a) (thermal ellipsoids at 30% probability); the direction of intermolecular N−H···O hydrogen bonding is indicated by dashed lines. Ellipsoid plot of 1-Boc-5-benzoyl-5-hydroxypyrazoline 5a. ORTEP plot and

• dimer of compound 5r (thermal ellipsoids at 30% probability). Glyoxylation–alkynylation (GA) and activation–alkynylation (AA) synthesis of alkynediones in a one-pot fashion. Consecutive three-component synthesis to give 5-benzoyl-3-phenyl-1H-pyrazole (6a) after alkaline deacylation of intermediate 5a

Formation of an unexpected 3,3-diphenyl-3H-indazole through a facile intramolecular [2 + 3] cycloaddition of the diazo intermediate

• Andrew T. King,
• Hugh G. Hiscocks,
• Lidia Matesic,
• Mohan Bhadbhade,
• Roger Bishop and
• Alison T. Ung

Beilstein J. Org. Chem. 2019, 15, 1347–1354, doi:10.3762/bjoc.15.134

• . Possible compounds with the molecular formula C33H26N2O (structure 7 contains 27 hydrogen atoms). ORTEP view of the molecule 8 showing the atom labelling (ellipsoids are drawn at 50% probability level). Significant intermolecular interactions made by the benzhydryl group (a, upper) and the gem-diphenyl

Doebner-type pyrazolopyridine carboxylic acids in an Ugi four-component reaction

• Maryna V. Murlykina,
• Oleksandr V. Kolomiets,
• Maryna M. Kornet,
• Yana I. Sakhno,
• Sergey M. Desenko,
• Victoriya V. Dyakonenko,
• Svetlana V. Shishkina,
• Oleksandr A. Brazhko,
• Vladimir I. Musatov,
• Alexander V. Tsygankov,
• Erik V. Van der Eycken and
• Valentyn A. Chebanov

Beilstein J. Org. Chem. 2019, 15, 1281–1288, doi:10.3762/bjoc.15.126

• -(4-chlorophenyl)-2-oxoethyl)-6-(4-methoxyphenyl)-3-methyl-N-p-tolyl-1H-pyrazolo[3,4-b]pyridine-4-carboxamide (11n) according to X-ray diffraction data. Non-hydrogen atoms are presented as thermal ellipsoids with 50% probability. An overview of heterocyclic acids used in the Ugi reaction. Synthesis of

Understanding the unexpected effect of frequency on the kinetics of a covalent reaction under ball-milling conditions

• Ana M. Belenguer,
• Adam A. L. Michalchuk,
• Giulio I. Lampronti and
• Jeremy K. M. Sanders

Beilstein J. Org. Chem. 2019, 15, 1226–1235, doi:10.3762/bjoc.15.120

• the temperature term of the traditional Arrhenius equation can be (to a first approximation) replaced by the rate of supply of mechanical energy, W [29], (Equation 2) Hence, k2 represents the ‘per impact’ probability of reaction. We note that the individual terms of Equation 2 are indeed expected to

• ) can dominate subsequent stages of the transformation, as the probability of contact formation decreases. While further work is required to capture detailed mechanistic insight, we can suggest that kinetic modelling of covalent mechanochemical reactions likely requires a model that accounts for both