Synthesis and properties of 6-alkynyl-5-aryluracils

• Ruben Manuel Figueira de Abreu,
• Till Brockmann,
• Alexander Villinger,
• Peter Ehlers and
• Peter Langer

Beilstein J. Org. Chem. 2024, 20, 898–911, doi:10.3762/bjoc.20.80

• molecules within and between a layer with two molecules at the top and the bottom of the unit cell. b) Determined from X-ray structural analysis at 123 K. Element color: carbon (grey), hydrogen (white), oxygen (red) and nitrogen (blue). The thermal ellipsoids are drawn at the 50% probability level. UV–vis

Synthesis of imidazo[4,5-e][1,3]thiazino[2,3-c][1,2,4]triazines via a base-induced rearrangement of functionalized imidazo[4,5-e]thiazolo[2,3-c][1,2,4]triazines

• Dmitry B. Vinogradov,
• Alexei N. Izmest’ev,
• Angelina N. Kravchenko,
• Yuri A. Strelenko and
• Galina A. Gazieva

Beilstein J. Org. Chem. 2023, 19, 1047–1054, doi:10.3762/bjoc.19.80

• –spin interaction constants of other doublets (2JCH = 1.3–1.5 Hz) indicate the position of the carboxyl (for 4a, red) or carbonyl (for 5a, blue) groups through two bonds relative to the olefinic proton. The structure of compound 5a was additionally confirmed by X-ray structural analysis data (Figure 5

Inclusion complexes of the steroid hormones 17β-estradiol and progesterone with β- and γ-cyclodextrin hosts: syntheses, X-ray structures, thermal analyses and API solubility enhancements

• Alexios I. Vicatos,
• Zakiena Hoossen and
• Mino R. Caira

Beilstein J. Org. Chem. 2022, 18, 1749–1762, doi:10.3762/bjoc.18.184

• and DSC results for each sample are available (Section 5, pp. S15 and S16 in Supporting Information File 1). Single crystal X-ray structural analysis The crystal structures of β-CD·BES, β-CD·PRO and γ-CD·PRO were solved by isomorphous replacement using as trial models the rigid host atom frameworks of

Synthesis, optical and electrochemical properties of (D–π)₂-type and (D–π)₂Ph-type fluorescent dyes

• Kosuke Takemura,
• Kazuki Ohira,
• Taiki Higashino,
• Keiichi Imato and
• Yousuke Ooyama

Beilstein J. Org. Chem. 2022, 18, 1047–1054, doi:10.3762/bjoc.18.106

• , compared with those in toluene. The Φfl-solid (0.24) of OTT-2 is higher than that (Φfl-solid = 0.15) of OTK-2, while the Φfl-solid of OTK-2 and OTT-2 are lower than those in toluene. Although single crystals of OTK-2 and OTT-2 with sufficient size for X-ray structural analysis were not obtained, the

Synthesis of bis-spirocyclic derivatives of 3-azabicyclo[3.1.0]hexane via cyclopropene cycloadditions to the stable azomethine ylide derived from Ruhemann's purple

• Alexander S. Filatov,
• Olesya V. Khoroshilova,
• Anna G. Larina,
• Vitali M. Boitsov and
• Alexander V. Stepakov

Beilstein J. Org. Chem. 2022, 18, 769–780, doi:10.3762/bjoc.18.77

• triple bonds due to ring strain. It is noteworthy that we managed to determine the relative configuration of cycloadduct 3e by carrying out the corresponding X-ray structural analysis (Figure 1 and Table S2 in Supporting Information File 1). As anticipated, the azomethine ylide 1 cycloaddition to

The enzyme mechanism of patchoulol synthase

• Houchao Xu,
• Bernd Goldfuss,
• Gregor Schnakenburg and
• Jeroen S. Dickschat

Beilstein J. Org. Chem. 2022, 18, 13–24, doi:10.3762/bjoc.18.2

• no. 1491695) [17], but these data did not allow to conclude on the absolute configuration of compound 3. We now obtained 3 as a crystalline material and performed an X-ray structural analysis through anomalous dispersion using Cu Kα irradiation (Table S2 in Supporting Information File 1), resulting

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

• -QN-BF4 30-3, and F-QD-BF4 30-4 in good yields (Scheme 69). Soon after in 2001, they reported the X-ray structural analysis of F-CD-BF4 30-1 [98]. The enantioselective fluorination of the sodium enolate of 2-methyl-1-tetralone was examined using these N-F alkaloid salts (Scheme 70). F-CD-BF4 30-1 gave

Amino- and polyaminophthalazin-1(2H)-ones: synthesis, coordination properties, and biological activity

• Zbigniew Malinowski,
• Emilia Fornal,
• Agata Sumara,
• Renata Kontek,
• Karol Bukowski,
• Beata Pasternak,
• Dariusz Sroczyński,
• Joachim Kusz,
• Magdalena Małecka and
• Monika Nowak

Beilstein J. Org. Chem. 2021, 17, 558–568, doi:10.3762/bjoc.17.50

• compound moiety. Based on the results of X-ray structural analysis of the Cu(II) complex with 7, it can be assumed, that also in the case of ligand 5i (L2) the nitrogen atoms of the pyridin-2-yl and azomethin moiety participate in the coordination with Cu(II) ions. Crystallography of complex 17 The copper

Synthesis, crystal structures and properties of carbazole-based [6]helicenes fused with an azine ring

• Daria I. Tonkoglazova,
• Anna V. Gulevskaya,
• Konstantin A. Chistyakov and
• Olga I. Askalepova

Beilstein J. Org. Chem. 2021, 17, 11–21, doi:10.3762/bjoc.17.2

• without THF solvent producing alkyne 9b in 82% yield (Table 4, entry 2). The structure of 9c was unambiguously proved by X-ray structural analysis (see Supporting Information File 1, Figure S34). Earlier, at the final step of a similar synthesis of the azine-fused [5]helicenes, we used trifluoroacetic

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

• . Supporting Information File 266: Crystal structure information files for 1, 3, and 5. Acknowledgements The authors thank the Rigaku Corporation for the single-crystal X-ray structural analysis of talaromycone A. The authors are also grateful to Dr. Hiromi Ota at the Division of Instrumental Analysis for the

Synthesis, photophysical and electrochemical properties of pyridine, pyrazine and triazine-based (D–π–)₂A fluorescent dyes

• Keiichi Imato,
• Toshiaki Enoki,
• Koji Uenaka and
• Yousuke Ooyama

Beilstein J. Org. Chem. 2019, 15, 1712–1721, doi:10.3762/bjoc.15.167

• dye molecules in the solid state, although we could not prepare single crystals of OUY-2, OUK-2 and OUJ-2 for the X-ray structural analysis. Electrochemical properties The electrochemical properties of OUY-2, OUK-2 and OUJ-2 were investigated by cyclic voltammetry (CV) in DMF containing 0.1 M

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

• the indazole ring. The ambiguity was overcome through the X-ray structural analysis of the compound. The single crystals were easily obtained by recrystallisation from CH2Cl2. Crystal structure analysis The X-ray crystal analysis revealed that the product was not the diazonium intermediate 7, but

Synthesis of pyrrolidine-based hamamelitannin analogues as quorum sensing inhibitors in Staphylococcus aureus

• Jakob Bouton,
• Kristof Van Hecke,
• Reuven Rasooly and
• Serge Van Calenbergh

Beilstein J. Org. Chem. 2018, 14, 2822–2828, doi:10.3762/bjoc.14.260

• which the cationic character of the pyrrolidine nitrogen is removed, were also synthesized. The correct stereochemistry of the synthesized analogues was unequivocally proven via X-ray structural analysis of compound 3a (Figure 2). Biological evaluation The synthesized analogues were tested in a S

Recent advances in hypervalent iodine(III)-catalyzed functionalization of alkenes

• Xiang Li,
• Pinhong Chen and
• Guosheng Liu

Beilstein J. Org. Chem. 2018, 14, 1813–1825, doi:10.3762/bjoc.14.154

• epoxidation products. Not only terminal styrenes but also internal alkenes were suitable to this reaction, affording the anti-diamination products. The exact mode of stereoinduction with the new catalyst 23 was examined, and the single crystal X-ray structural analysis of 26 revealed that a water molecule

A chiral analog of the bicyclic guanidine TBD: synthesis, structure and Brønsted base catalysis

• Mariano Goldberg,
• Denis Sartakov,
• Jan W. Bats,
• Michael Bolte and
• Michael W. Göbel

Beilstein J. Org. Chem. 2016, 12, 1870–1876, doi:10.3762/bjoc.12.176

• (42%, 48% ee) yielded 26% of material with 95% ee. Assignment of absolute configurations (Scheme 3): Well grown crystals of enantiopure Michael product 30 suitable for X-ray structural analysis could be obtained by a second recrystallization from CH2Cl2/cyclohexane. The 4-bromophenyl residue allowed

Modular synthesis of the pyrimidine core of the manzacidins by divergent Tsuji–Trost coupling

• Sebastian Bretzke,
• Stephan Scheeff,
• Felicitas Vollmeyer,
• Friederike Eberhagen,
• Frank Rominger and
• Dirk Menche

Beilstein J. Org. Chem. 2016, 12, 1111–1121, doi:10.3762/bjoc.12.107

• an X-ray structure of tert-butylsulfinylamine 28 was obtained. Remarkably, these types of substances have not been broadly evaluated by X-ray structural analysis which adds to the importance of this general evaluation. Next, we focused on further homologation towards a suitably functionalized urea

Grubbs–Hoveyda type catalysts bearing a dicationic N-heterocyclic carbene for biphasic olefin metathesis reactions in ionic liquids

• Maximilian Koy,
• Hagen J. Altmann,
• Benjamin Autenrieth,
• Wolfgang Frey and
• Michael R. Buchmeiser

Beilstein J. Org. Chem. 2015, 11, 1632–1638, doi:10.3762/bjoc.11.178

• . Selected bond lengths (pm) for Ru-2 and Ru-1 [21]. ROMP reactions under biphasic conditions.a,b ROMP of M1 under biphasic conditions with recycling.a Supporting Information Supporting Information File 310: Analytical data for Ru-2, the polymers prepared, details on the single crystal X-ray structural

• analysis of Ru-2, results for biphasic RCM. Acknowledgements Financial support provided by the Deutsche Forschungsgemeinschaft (DFG, grant no. BU 2174/8-1) is gratefully acknowledged.

The chemical behavior of terminally tert-butylated polyolefins

• Dagmar Klein,
• Henning Hopf,
• Peter G. Jones,
• Ina Dix and
• Ralf Hänel

Beilstein J. Org. Chem. 2015, 11, 1246–1258, doi:10.3762/bjoc.11.139

• (as well as many of their precursors) were characterized by X-ray structural analysis. These polyolefins are substructures of the most famous polyene, “polyacetylene”. Having prepared and unambiguously characterized the hydro-carbons 2, we now turn to their chemical behavior. In the sense that these

• prepare crystals of 17 suitable for an X-ray structural analysis. Interestingly, Kuhn and Winterstein in their study on the chemical behavior of α,ω-diphenyloligoenes obtained different results: for 1,4-diphenylbuta-1,3-diene, bromine addition furnished the 1,2-adduct in 95% yield [3]. As in the case of

• produced in good yield (73%). The compound could be kept at −10 °C without decomposition for considerable times and was recrystallized from pentane to provide needles "suitable" for X-ray structural analysis; its qualitative structure in the solid state is reproduced in Figure 3, but should be interpreted

The preparation of new functionalized [2.2]paracyclophane derivatives with N-containing functional groups

• Henning Hopf,
• Swaminathan Vijay Narayanan and
• Peter G. Jones

Beilstein J. Org. Chem. 2015, 11, 437–445, doi:10.3762/bjoc.11.50

• ) resulted in the formation of the next higher homolog 19 (73%). Both compounds were readily characterized by their analytical data (see Supporting Information File 1) and also by an X-ray structural analysis of 18. Several features are common to all structures presented in this paper. The usual features of

• characterized by their spectroscopic data (Supporting Information File 1), and for 22 we could additionally determine the solid-state structure by X-ray structural analysis (Figure 4a). The orientation of the side chains in 22 is described by the torsion angles C14–C15–N1–C17 131.2(2)°, C15–N1–C17–O −1.3(2

• preparation of various cyclophanes bearing substituents with nitrogen-containing functional groups, e.g., the pseudo-ortho diamine 8, the bis secondary amine 23, and the crownophanes 18 and 19. Several of these new cyclophane derivatives (18, 19, 22, 26, 28) have been characterized by X-ray structural

Five-membered ring annelation in [2.2]paracyclophanes by aldol condensation

• Henning Hopf,
• Swaminathan Vijay Narayanan and
• Peter G. Jones

Beilstein J. Org. Chem. 2014, 10, 2021–2026, doi:10.3762/bjoc.10.210

• -38106 Braunschweig, Germany 10.3762/bjoc.10.210 Abstract Under basic conditions 4,5,12,13-tetraacetyl[2.2]paracyclophane (9) cyclizes by a double aldol condensation to provide the two aldols 12 and 15 in a 3:7 ratio. The structures of these compounds were obtained from X-ray structural analysis

• deuteriochloroform) that combine to form a complex three-dimensional pattern (Table 1). Several attempts to obtain crystals of the major isomer 15 suitable for X-ray analysis failed. The anti-orientation of the carbonyl groups of compound 15 was proved by the X-ray structural analysis of the product resulting from a

Building complex carbon skeletons with ethynyl[2.2]paracyclophanes

• Ina Dix,
• Lidija Bondarenko,
• Peter G. Jones,
• Thomas Oeser and
• Henning Hopf

Beilstein J. Org. Chem. 2014, 10, 2013–2020, doi:10.3762/bjoc.10.209

• their usual spectroscopic and analytical data, the new cyclophanes 11, 12, 19, 20, 22, and 26 were characterized by X-ray structural analysis. Keywords: carbon-rich molecules; complex carbon scaffolds; cyclophanes; Glaser coupling; multibridged cyclophanes; X-ray analysis; Introduction Several years

• recrystallized to provide single crystals suitable for X-ray structural analysis. Figure 1 shows that dimer 11 indeed possesses the “crossed” structure; it crystallizes with imposed twofold symmetry, but the effective (non-crystallographic) symmetry is the unusual D2 (222) with r.m.s. deviation 0.01 Å. Despite

Intermediates in monensin biosynthesis: A late step in biosynthesis of the polyether ionophore monensin is crucial for the integrity of cation binding

• Wolfgang Hüttel,
• Jonathan B. Spencer and
• Peter F. Leadlay

Beilstein J. Org. Chem. 2014, 10, 361–368, doi:10.3762/bjoc.10.34

• crystallised as their monosodium salts from an isohexane/ethyl acetate mixture and single crystals were subjected to X-ray structural analysis (Figure 2). Dehydroxydemethylmonensin A did not form crystals under any conditions tested. When the demethylmonensin A structure is overlaid on the structure of the

Modulating NHC catalysis with fluorine

• Yannick P. Rey and
• Ryan Gilmour

Beilstein J. Org. Chem. 2013, 9, 2812–2820, doi:10.3762/bjoc.9.316

• catalyst 10 (Scheme 3; lower) was prepared in a short synthesis starting from the primary bromide 23 [22]. Hydrogenolysis (24, 67%) [41] and subsequent conversion to the triazolium salt completed the short synthesis (52% over 3 steps). X-Ray structural analysis of 5, 6 and 7 The X-ray crystal structures of

The preparation of several 1,2,3,4,5-functionalized cyclopentane derivatives

• André S. Kelch,
• Peter G. Jones,
• Ina Dix and
• Henning Hopf

Beilstein J. Org. Chem. 2013, 9, 1705–1712, doi:10.3762/bjoc.9.195

• with various bromination reagents. Whenever possible we confirm the structures of intermediate compounds or byproducts by X-ray structural analysis. Results and Discussion cis,cis,cis,cis-1,2,3,4,5-Pentakis(hydroxymethyl)cyclopentane (16) and derivatives The pentaalcohol 16 is a known compound, having

• silica gel, the main isomer began to crystallize partially from the highly viscous hydrogenation mixture after standing for several months. The crystals obtained were suitable for X-ray structural analysis, which showed that this isomer has the cis,cis,cis,trans-geometry, i.e. 26 (Figure 3). The

• the best results. Under these conditions the hexabromide 32 was produced in 45% yield. The structure of this cyclopentadiene derivative was derived from its spectroscopic data (see Supporting Information File 1) and also by an X-ray structural analysis (Figure 4). A rationalization of the route from 8

Isolation and X-ray characterization of palladium–N complexes in the guanylation of aromatic amines. Mechanistic implications

• Abdessamad Grirrane,
• Hermenegildo Garcia and
• Eleuterio Álvarez

Beilstein J. Org. Chem. 2013, 9, 1455–1462, doi:10.3762/bjoc.9.165

• complexes of the type of bis(guanidino)Pd(II) (4a–c) (Scheme 2) whose structures have been characterized by single-crystal X-ray structural analysis, as well as to obtain evidence for the intermediacy of these complexes in the catalytic process. Overall the present data reinforce the previous proposal for