One-pot syntheses of blue-luminescent 4-aryl-1H-benzo[f]isoindole-1,3(2H)-diones by T3P^® activation of 3-arylpropiolic acids

• Melanie Denißen,
• Alexander Kraus,
• Guido J. Reiss and
• Thomas J. J. Müller

Beilstein J. Org. Chem. 2017, 13, 2340–2351, doi:10.3762/bjoc.13.231

• . Supporting Information The Supporting Information contains all experimental procedures, spectroscopic and analytical data as well as copies of NMR spectra of compounds 2, 4, 5, and 6. X-ray structure analyses of compounds 4b, 5, and 6, and Hammett–Taft correlations of compounds 4a,b,d–f are also given

Synthesis and photophysical properties of novel benzophospholo[3,2-b]indole derivatives

• Mio Matsumura,
• Mizuki Yamada,
• Atsuya Muranaka,
• Misae Kanai,
• Naoki Kakusawa,
• Daisuke Hashizume,
• Masanobu Uchiyama and
• Shuji Yasuike

Beilstein J. Org. Chem. 2017, 13, 2304–2309, doi:10.3762/bjoc.13.226

• -dimethylaniline. Using the obtained benzophosphole-fused indole as a common starting material, simple modifications were carried out at the phosphorus center of the phosphole, synthesizing various functionalized analogs. The X-ray structure analysis of trivalent phosphole and phosphine oxide showed that the fused

Mechanochemical Knoevenagel condensation investigated in situ

• Sebastian Haferkamp,
• Franziska Fischer,
• Werner Kraus and
• Franziska Emmerling

Beilstein J. Org. Chem. 2017, 13, 2010–2014, doi:10.3762/bjoc.13.197

• grinding process, whereas p-nitrobenzaldehyde remains crystalline until the onset of the product formation. The crystalline product was of sufficient quality for single crystal X-ray structure determination. Results and Discussion Scheme 1 illustrates the investigated Knoevenagel condensation of p

Molecular recognition of N-acetyltryptophan enantiomers by β-cyclodextrin

• Spyros D. Chatziefthimiou,
• Mario Inclán,
• Petros Giastas,
• Athanasios Papakyriakou,
• Konstantina Yannakopoulou and
• Irene M. Mavridis

Beilstein J. Org. Chem. 2017, 13, 1572–1582, doi:10.3762/bjoc.13.157

• crystallization, as a consequence of accumulation of many soft host–guest interactions and of the imposed crystallographic order, thus resulting in very dissimilar propensity of each enantiomer to produce crystals with β-CD. Keywords: β-cyclodextrin; enantiomeric discrimination; N-acetyltryptophan; NMR; X-ray

• structure; Introduction Cyclodextrins (CDs) are cyclic, water-soluble carbohydrates with a rather non-polar cavity that can host a variety of organic molecules (guests) and form inclusion complexes [1]. The guest molecules may be completely or partly enclosed inside the cavity depending on their size and

A speedy route to sterically encumbered, benzene-fused derivatives of privileged, naturally occurring hexahydropyrrolo[1,2-b]isoquinoline

• Olga Bakulina,
• Alexander Ivanov,
• Vitalii Suslonov,
• Dmitry Dar’in and
• Mikhail Krasavin

Beilstein J. Org. Chem. 2017, 13, 1413–1424, doi:10.3762/bjoc.13.138

• chloroform. Anti- and syn-diastereomers of 10 and 10'. Single-crystal X-ray structure of compound 10l. Typical J(H11-H11a)-values and corresponding dihedral angles for syn- and anti-diastereomers of compounds 10 derived from 2H-indolenines. The difference in the 13C NMR chemical shifts of the angular methyl

Glycoscience@Synchrotron: Synchrotron radiation applied to structural glycoscience

• Serge Pérez and
• Daniele de Sanctis

Beilstein J. Org. Chem. 2017, 13, 1145–1167, doi:10.3762/bjoc.13.114

• and solving the X-ray structure of this intermediate [75]. The A and B antigenic determinants are synthesised by the blood group A (GTA) and the blood group B (GTB) glycosyltransferases which transfer GalNAc from UDP-GalNAc for the A type and a Gal residue from UDP-Gal for the B-type. A mutant of the

G-Protein coupled receptors: answers from simulations

• Timothy Clark

Beilstein J. Org. Chem. 2017, 13, 1071–1078, doi:10.3762/bjoc.13.106

• atomistic resolution are needed to decipher the intimate details of the modes of action of GPCRs. X-ray crystallographic studies on GPCRs are, however, fraught with difficulties [6]. The structure of rhodopsin, the first GPCR X-ray structure, was published in 2000 [7], was not followed by the second, the β2

• relevant one than the X-ray structure. Also, the simulations do not need the modifications outlined above for obtaining suitable crystals; they can be performed for the original biological system. Thus, simulations can reasonably be expected in many cases to give a closer picture of the biological

• a mechanism for allosteric modulation for the muscarinic M2 receptor [33]. Most importantly, though, long unconstrained simulations were able to demonstrate the deactivation of an active conformation of the β2-adrenergic receptor (taken from the X-ray structure) [18] in binary ligand–receptor

A strategic approach to [6,6]-bicyclic lactones: application towards the CD fragment of DHβE

• Tue Heesgaard Jepsen,
• Emil Glibstrup,
• François Crestey,
• Anders A. Jensen and
• Jesper Langgaard Kristensen

Beilstein J. Org. Chem. 2017, 13, 988–994, doi:10.3762/bjoc.13.98

• from our previous deconstruction approach [3] and a few degradation studies [6][7]. Balle and co-workers recently published an X-ray structure of the acetylcholine binding protein (AChBP) in complex with DHβE [8] and based on this structure, two key pharmacophores of DHβE were proposed as shown in

Synthesis of tetrasubstituted pyrazoles containing pyridinyl substituents

• Josef Jansa,
• Ramona Schmidt,
• Ashenafi Damtew Mamuye,
• Laura Castoldi,
• Alexander Roller,
• Vittorio Pace and
• Wolfgang Holzer

Beilstein J. Org. Chem. 2017, 13, 895–902, doi:10.3762/bjoc.13.90

• Organic Syntheses (VUOS), Rybitví 296, CZ-533 54 Pardubice-Rybitví, Czech Republic Department of Organic Chemistry, Faculty of Science, Palacký University, 17. listopadu 1192/12, CZ-771 46 Olomouc, Czech Republic X-ray Structure Analysis Centre, Faculty of Chemistry, University of Vienna, Währinger Straße

• condensation product was confirmed by crystal structure analysis. Keywords: Negishi coupling; NMR (1H; 13C; 15N); pyrazole; pyridine; X-ray structure analysis; Introduction The pyrazole nucleus is a frequently occurring motif in many pharmaceuticals [1][2] and biologically active compounds [3][4

• [3,4-a]quinolizin-6-ium structure 12 was established, which was confirmed by single crystal X-ray structure analysis (see Supporting Information File 1), proving also iodide as the corresponding anion [39] which acts as a leaving group in the coupling reaction and also could origin from the CuI co

First total synthesis of kipukasin A

• Chuang Li,
• Haixin Ding,
• Zhizhong Ruan,
• Yirong Zhou and
• Qiang Xiao

Beilstein J. Org. Chem. 2017, 13, 855–862, doi:10.3762/bjoc.13.86

• kipukasin A. X-ray structure of compound 13. Synthesis of 2,4-dimethoxy-6-methylbenzoic chloride. Reagents and conditions: (a) POCl3, DMF, 0 °C to rt, 75%; (b) MeI, K2CO3, acetone, rt, 93%; (c) NaClO2, NaH2PO4, DMSO, rt, 81%; (d) (COCl)2, CH2Cl2, refux. Total synthesis of kipukasin A. Reagents and

Nucleophilic and electrophilic cyclization of N-alkyne-substituted pyrrole derivatives: Synthesis of pyrrolopyrazinone, pyrrolotriazinone, and pyrrolooxazinone moieties

• Işıl Yenice,
• Sinan Basceken and
• Metin Balci

Beilstein J. Org. Chem. 2017, 13, 825–834, doi:10.3762/bjoc.13.83

• and methylene protons in 13c and 16 with the relevant carbon atoms (from the HMBC spectrum). Single-crystal X-ray structure of 12c shown with 40% probability displacement ellipsoids. The structure of allene 17 formed during the reaction of 7d with a base. Single-crystal X-ray structure of 19c shown

Fluorinated cyclohexanes: Synthesis of amine building blocks of the all-cis 2,3,5,6-tetrafluorocyclohexylamine motif

• Tetiana Bykova,
• Nawaf Al-Maharik,
• Alexandra M. Z. Slawin and
• David O'Hagan

Beilstein J. Org. Chem. 2017, 13, 728–733, doi:10.3762/bjoc.13.72

• chromatography. Finally fluorination of 10b and 10c in separate reactions with Et3N·3HF at 120 °C furnished nitrile 11b (51% yield) and 11c (31% yield) respectively. The structure and stereochemistry of both products were unambiguously confirmed by X-ray structure analysis (Scheme 3). Reduction of 11b with

• nickel boride delivered amine 5b in 65% yield as a crystalline solid and an analogous reduction of 11c generated the racemic amine 5c as a colourless liquid. The structure of 11b was confirmed by X-ray structure analysis (Scheme 3). Amines 5a and 5b were reacted with terephthaloyl chloride as a means of

• . However suitable crystals were obtained from acetone/acetonitrile for X-ray structure analysis. The X-ray structures of 13, 14 and 15 are illustrated in Figure 2. It was assumed that the facial polarity of the tetrafluorocyclohexane rings would be apparent in the molecular ordering in the solid state

Inclusion complexes of β-cyclodextrin with tricyclic drugs: an X-ray diffraction, NMR and molecular dynamics study

• Franca Castiglione,
• Fabio Ganazzoli,
• Luciana Malpezzi,
• Andrea Mele,
• Walter Panzeri and
• Giuseppina Raffaini

Beilstein J. Org. Chem. 2017, 13, 714–719, doi:10.3762/bjoc.13.70

• comparison of the X-ray structure and the MD simulations in water of 2/β-CD complex showed that 2 is present as single conformer in the crystal and in two conformations in the solution state. Materials and Methods X-ray diffraction Single crystals of 1/β-CD and 2/β-CD were obtained after many attempts by

Derivatives of the triaminoguanidinium ion, 5. Acylation of triaminoguanidines leading to symmetrical tris(acylamino)guanidines and mesoionic 1,2,4-triazolium-3-aminides

• Jan Szabo,
• Julian Greiner and
• Gerhard Maas

Beilstein J. Org. Chem. 2017, 13, 579–588, doi:10.3762/bjoc.13.57

• , indicate a static, unsymmetrical molecule around 300 K, showing for example separate signals for the three CH2 and Ccarbonyl nuclei. A single-crystal X-ray structure determination was performed for 6b, which gave suitable crystals of 6b·2C2H5OH when crystallized from ethanol. The guanidine structure could

Secondary metabolome and its defensive role in the aeolidoidean Phyllodesmium longicirrum, (Gastropoda, Heterobranchia, Nudibranchia)

• Alexander Bogdanov,
• Cora Hertzer,
• Stefan Kehraus,
• Samuel Nietzer,
• Sven Rohde,
• Peter J. Schupp,
• Heike Wägele and
• Gabriele M. König

Beilstein J. Org. Chem. 2017, 13, 502–519, doi:10.3762/bjoc.13.50

• of [α]D20 +160 [31]. X-ray structure determination performed by Bernstein et al. for the closely related sarcophine (epoxide function at C-7, C-8) revealed also 2S configuration [38]. Sarcophine exhibited a negative Cotton effect at 246 nm. A CD measurement of bisepoxide 12 in acetonitrile did not

Highly bulky and stable geometry-constrained iminopyridines: Synthesis, structure and application in Pd-catalyzed Suzuki coupling of aryl chlorides

• Yi Lai,
• Zhijian Zong,
• Yujie Tang,
• Weimin Mo,
• Nan Sun,
• Baoxiang Hu,
• Zhenlu Shen,
• Liqun Jin,
• Wen-hua Sun and
• Xinquan Hu

Beilstein J. Org. Chem. 2017, 13, 213–221, doi:10.3762/bjoc.13.24

• -ray crystallography were performed on a Bruker Smart Apex CCD area detector diffractometer using graphite-monochromated Mo Kα radiation (λ = 0.71073 Å). Details of the X-ray structure determinations and refinements are provided in Table 5. According to the synthetic procedures in the literature, the

Silyl-protective groups influencing the reactivity and selectivity in glycosylations

• Mikael Bols and
• Christian Marcus Pedersen

Beilstein J. Org. Chem. 2017, 13, 93–105, doi:10.3762/bjoc.13.12

• the NMR spectrum of this compound displayed line broadening indicating some conformational inversion, but the X-ray structure of the crystalline compound was in the conventional 1C4 conformation. Yet the compound was clearly very reactive as it selectively could glycosylate the 2-OH of thioglycoside

Diastereoselective anodic hetero- and homo-coupling of menthol-, 8-methylmenthol- and 8-phenylmenthol-2-alkylmalonates

• Matthias C. Letzel,
• Hans J. Schäfer and
• Roland Fröhlich

Beilstein J. Org. Chem. 2017, 13, 33–42, doi:10.3762/bjoc.13.5

• diastereoselectivity ranging from 5 to 65% de. Electrolyses without a coacid led to diastereomeric homo-coupling products in 21–50% yield with ratios of diastereomers being 1.17:2.00:0.81 to 7.03:2.00. The stereochemistry of the new stereogenic centers was confirmed by X-ray structure analysis and 13C NMR data

Supramolecular frameworks based on [60]fullerene hexakisadducts

• Andreas Kraft,
• Johannes Stangl,
• Ana-Maria Krause,
• Klaus Müller-Buschbaum and
• Florian Beuerle

Beilstein J. Org. Chem. 2017, 13, 1–9, doi:10.3762/bjoc.13.1

• electron microscopy were carried out on activated and non-activated samples of HFF-3. They corroborate the strong anisotropic character of crystalline needles of the X-ray structure determination and do not show changes upon activation (see Figure S13 in Supporting in Information File 1). However, powder X

Organofluorine chemistry: Difluoromethylene motifs spaced 1,3 to each other imparts facial polarity to a cyclohexane ring

• Mathew J. Jones,
• Ricardo Callejo,
• Alexandra M. Z. Slawin,
• Michael Bühl and
• David O'Hagan

Beilstein J. Org. Chem. 2016, 12, 2823–2827, doi:10.3762/bjoc.12.281

• offer new possibilities for the design of performance molecules extending from organic materials research to medicinal chemistry. Selected fluorinated polar alicyclic scaffolds. X-ray structure of compound 4c. The image shows two molecules stacked with the non-fluorine face pointing to an adjacent

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

• was possible by comparison of the experimental and DFT-calculated VCD spectra (Figure 5) with a satisfactory ESI value of 80%. Eventually, the absolute configuration of (S)-3 could be unambiguously determined by X-ray structure analysis of a single crystal, which was obtained by slow cooling of a hot

From betaines to anionic N-heterocyclic carbenes. Borane, gold, rhodium, and nickel complexes starting from an imidazoliumphenolate and its carbene tautomer

• Ming Liu,
• Jan C. Namyslo,
• Martin Nieger,
• Mika Polamo and
• Andreas Schmidt

Beilstein J. Org. Chem. 2016, 12, 2673–2681, doi:10.3762/bjoc.12.264

• of the carbene atom appears at δ = 183.9 ppm. Single crystals of the gold complex 9 were obtained by slow evaporation of a concentrated solution of 9 in MeOH and a molecular drawing is shown in Figure 3. The X-ray structure revealed a mixed occupation of the same position with chloride and bromide

Sydnone C-4 heteroarylation with an indolizine ring via Chichibabin indolizine synthesis

• Florin Albota,
• Mino R. Caira,
• Constantin Draghici,
• Florea Dumitrascu and
• Denisa E. Dumitrescu

Beilstein J. Org. Chem. 2016, 12, 2503–2510, doi:10.3762/bjoc.12.245

• formation of sydnone-indolizines 12. Supporting Information Experimental details of synthetic procedures and experimental details of X-ray structure analyses. Crystallographic information files (CIF) for compound 9d and 12c, listing crystal data, experimental and refinement details, and molecular

Synthesis, dynamic NMR characterization and XRD studies of novel N,N’-substituted piperazines for bioorthogonal labeling

• Constantin Mamat,
• Marc Pretze,
• Matthew Gott and
• Martin Köckerling

Beilstein J. Org. Chem. 2016, 12, 2478–2489, doi:10.3762/bjoc.12.242

• showed a Tc of 248 K with a ΔG# of 11.1 kJ/mol [23] whereas piperidine shows a higher ΔG# of 42.3 and N-methylpiperidine a ΔG# = 49.8 kJ/mol [21][28]. X-ray structure analyses of 3a and 4b Single crystals of 3a and 4b were obtained and their molecular structures determined using single crystal X-ray

• from coalescence temperatures Tc which were determined from dynamic 1H NMR measurements. The formation of conformers resulting from the partial double bond was additionally determined and verified using single crystal X-ray structure analysis. The second coalescence point is caused by the reduced

• structure analysis. Crystals of 3a have monoclinic symmetry of the space group C2/c. Crystals of 4b have monoclinic symmetry of the space group P21/n. The C14–C15 distance of 1.188(1) Å and the C13–C14–C15 angle of 178.2(1)° clearly indicate this group to be an alkyne residue, thus enabling the use of the

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

• via recrystallization or by passing the product through a short silica plug (see Table 1 and Supporting Information File 1 for details). Recrystallisation of 3 from a methanolic solution containing KClO4 yielded large, colourless, crystalline prisms. Single crystal X-ray structure determination