Aggregation behaviour of amphiphilic cyclodextrins: the nucleation stage by atomistic molecular dynamics simulations

• Giuseppina Raffaini,
• Antonino Mazzaglia and
• Fabio Ganazzoli

Beilstein J. Org. Chem. 2015, 11, 2459–2473, doi:10.3762/bjoc.11.267

• periodically saved for further analysis. The system equilibration was monitored by the time change of the total and potential energy of the system and of its components, and of relevant intermolecular distances, in particular those between the centres of mass of the interacting macrocycles. Based on these

• H and P groups in neighbouring macrocycles. Thus, in addition to a shallow self-inclusion of an H group, molecule B of Figure 7c shows inclusion of one H group in the macrocycle of C, and of two H groups in the macrocycle of A. Moreover, molecule A shows inclusion of one P group within the

• between the centers of mass of their macrocycles. These molecules are somewhat off-axis so as to optimize the interactions between their H groups that tightly inter-digitate, with a mutual shallow inclusion of a few of them into the cavity of the facing molecule. Furthermore, there is a looser side

Life lessons

• Jonathan R. Nitschke

Beilstein J. Org. Chem. 2015, 11, 2350–2354, doi:10.3762/bjoc.11.256

• ) macrocycles [1][2].

Beyond catalyst deactivation: cross-metathesis involving olefins containing N-heteroaromatics

• Kevin Lafaye,
• Cyril Bosset,
• Lionel Nicolas,
• Amandine Guérinot and
• Janine Cossy

Beilstein J. Org. Chem. 2015, 11, 2223–2241, doi:10.3762/bjoc.11.241

• for avoiding the nitrogen-induced deactivation of the catalyst by both electronic and steric effects (Scheme 22). Macrocycles embedding N-heteroaromatics have been prepared using a RCM reaction. Shirbate et al. used a RCM to synthesize normuscopyridine and analogues [62]. When a diastereomeric mixture

• hindrance may be invoked to explain the absence of catalyst deactivation (Scheme 24). Similarly, 15- to 18-membered ring macrocycles that incorporate an imidazole group were synthesized using a RCM of the corresponding dienes using GII as the catalyst (Scheme 25) [64][65][66]. By examining all these

• involving alkenes containing various N-heteroaromatics. Synthesis of dihydroisoquinoline using a RCM. Formation of tricyclic compound 59. RCM in the synthesis of normuscopyridine. Synthesis of macrocycle 64. Synthesis of macrocycles possessing an imidazole group. Retrosynthesis of an analogue of

Easy access to heterobimetallic complexes for medical imaging applications via microwave-enhanced cycloaddition

• Nicolas Desbois,
• Sandrine Pacquelet,
• Adrien Dubois,
• Clément Michelin and
• Claude P. Gros

Beilstein J. Org. Chem. 2015, 11, 2202–2208, doi:10.3762/bjoc.11.239

• agents for MRI. Indeed, manganese complexes of DOTA/NOTA macrocycles are thermodynamically less stable than other transition metal ions or Gd3+ analogues [13]. Over the years and to overcome this problem, a variety of Mn(III) porphyrins have been prepared and investigated for their potential use as MRI

Supramolecular chemistry: from aromatic foldamers to solution-phase supramolecular organic frameworks

• Zhan-Ting Li

Beilstein J. Org. Chem. 2015, 11, 2057–2071, doi:10.3762/bjoc.11.222

• Lin. I finished the synthesis of several fluorine-containing macrocycles and published my first research paper in the journal Heterocycles [2]. The starting materials for these macrocycles were initially designed for the preparation of biologically active molecules, which was the main project in this

• laboratory. Using them to prepare new macrocycles became a small independent dissertation project for me. In 1990, I joined Professor Qing-Yun Chen’s group as a Ph.D. candidate. Professor Chen is a distinguished, esteemed Chinese chemist in organic fluorine chemistry. His group developed new

• intramolecular hydrogen bonding, which is typical for aromatic amide backbones [40][41][42]. The diamine and diacyl chloride precursors for 21 had been used by Gong and co-workers to prepare the first family of hydrogen bonding-promoted aromatic amide macrocycles [43]. The main aim for designing these folded

Preparative semiconductor photoredox catalysis: An emerging theme in organic synthesis

• David W. Manley and
• John C. Walton

Beilstein J. Org. Chem. 2015, 11, 1570–1582, doi:10.3762/bjoc.11.173

• far accessed include adducts from alkenes and imines, a wide range of heterocycles from ring closures, radical homo-dimers and macrocycles as well as hydrogenated products from nitro-aromatics, alkenes and aldehydes. There is obvious scope for the discovery of additional donor and acceptor precursors

Synthesis and spectroscopic properties of β-triazoloporphyrin–xanthone dyads

• Dileep Kumar Singh and
• Mahendra Nath

Beilstein J. Org. Chem. 2015, 11, 1434–1440, doi:10.3762/bjoc.11.155

• fluorescence spectra of these porphyrin–xanthone dyads. Keywords: 1,3-dipolar cycloaddition; fluorescence; synthesis; triazoloporphyrin-xanthone dyads; UV–vis spectroscopy; Introduction In the past few decades, porphyrin macrocycles have emerged as a unique class of heterocyclic compounds and as most

Selected synthetic strategies to cyclophanes

• Sambasivarao Kotha,
• Mukesh E. Shirbhate and
• Gopalkrushna T. Waghule

Beilstein J. Org. Chem. 2015, 11, 1274–1331, doi:10.3762/bjoc.11.142

• -binding abilities, an improved affinity can be achieved by polytopic hosts [61][62][63] through multivalency effects in macrocycles. Olefin metathesis has played a key role in the development of cyclophane chemistry. Some of the catalysts used for this purpose are listed in Figure 3. The development of

• macrocycles. These molecules show excellent chiroptical properties such as high fluorescence quantum efficiency and a large circularly polarized luminescence dissymmetry factor. Cyclophanes are carbon-rich materials containing extensive alkyne moieties with a persistent molecular architecture. Orita and co

• have reported the synthesis of ethylene-bridged phenothiazinophane 92 using the McMurry coupling reaction. Also cyclic voltammetry experiments indicated the intramolecular electronic communication between the phenothiazinyl subunits. Calixarene-based macrocycles bind with various metal ions. Lee and

Hybrid macrocycle formation and spiro annulation on cis-syn-cis-tricyclo[6.3.0.0^2,6]undeca-3,11-dione and its congeners via ring-closing metathesis

• Sambasivarao Kotha,
• Ajay Kumar Chinnam and
• Rashid Ali

Beilstein J. Org. Chem. 2015, 11, 1123–1128, doi:10.3762/bjoc.11.126

• based macrocycle 6 involving Fischer indolization and ring-closing metathesis (RCM). Various spiro-polyquinane derivatives have been assembled via RCM as a key step. Keywords: aza-polyquiananes; Fischer indolization; macrocycles; ring-closing metathesis; spiropolyquinanes; Introduction Design and

Advances in the synthesis of functionalised pyrrolotetrathiafulvalenes

• Luke J. O’Driscoll,
• Sissel S. Andersen,
• Marta V. Solano,
• Dan Bendixen,
• Morten Jensen,
• Troels Duedal,
• Jess Lycoops,
• Cornelia van der Pol,
• Rebecca E. Sørensen,
• Karina R. Larsen,
• Kenneth Myntman,
• Christian Henriksen,
• Stinne W. Hansen and
• Jan O. Jeppesen

Beilstein J. Org. Chem. 2015, 11, 1112–1122, doi:10.3762/bjoc.11.125

• systems [11][27], to the incorporation of MPTTFs and BPTTFs into more complex molecular architectures such as macrocycles [8][9][14], calix-pyrroles [1][10][11], calixarenes [29] and porphyrins [30]. Note that for MPTTFs, R1 and R2 can be either the same or different. Here, we present recent developments

Carboxylated dithiafulvenes and tetrathiafulvalene vinylogues: synthesis, electronic properties, and complexation with zinc ions

• Yunfei Wang and
• Yuming Zhao

Beilstein J. Org. Chem. 2015, 11, 957–965, doi:10.3762/bjoc.11.107

• some TTFV-based macrocycles and polymers [12][28]. Previously, we have investigated a series of diphenyl-TTFVs with alkynyl groups attached to the phenyl units as synthetic building blocks, through which extension of π-conjugated structures could be conveniently executed via the Pd-catalysed coupling

Tuning of tetrathiafulvalene properties: versatile synthesis of N-arylated monopyrrolotetrathiafulvalenes via Ullmann-type coupling reactions

• Vladimir A. Azov,
• Diana Janott,
• Dirk Schlüter and
• Matthias Zeller

Beilstein J. Org. Chem. 2015, 11, 860–868, doi:10.3762/bjoc.11.96

• regioselective functionalization of TTF, however, remains problematic due to the presence of four identical attachment sites. Incorporation of the TTF moiety in macrocycles usually leads to poorly separable mixtures of cis/trans isomers [7][8][9]. Even if separation is possible, TTFs are prone to cis/trans

Synthesis of antibacterial 1,3-diyne-linked peptoids from an Ugi-4CR/Glaser coupling approach

• Martin C. N. Brauer,
• Ricardo A. W. Neves Filho,
• Bernhard Westermann,
• Ramona Heinke and
• Ludger A. Wessjohann

Beilstein J. Org. Chem. 2015, 11, 25–30, doi:10.3762/bjoc.11.4

• , this reaction has been used in the synthesis of bioactive peptides and pseudopeptides, e.g., tubulysin mimetics [13], julocrotine derivatives [14], architecturally complex peptoid macrocycles [15][16], building blocks for diversity-oriented synthesis [17], and heterocyclic compounds [18]. Complex

Synthesis of an organic-soluble π-conjugated [3]rotaxane via rotation of glucopyranose units in permethylated β-cyclodextrin

• Jun Terao,
• Yohei Konoshima,
• Akitoshi Matono,
• Hiroshi Masai,
• Tetsuaki Fujihara and
• Yasushi Tsuji

Beilstein J. Org. Chem. 2014, 10, 2800–2808, doi:10.3762/bjoc.10.297

• IMWs with polyrotaxane structures via polymerization of π-conjugated [1]rotaxane monomers bearing PMCDs as macrocycles [14]. Further, we confirmed that such IMWs with poly[1]rotaxane structure are highly soluble in a variety of organic solvents and have good rigidity, photoluminescence efficiency [15

Mono- and multilayers of molecular spoked carbazole wheels on graphite

• Stefan-S. Jester,
• A. Vikas Aggarwal,
• Daniel Kalle and
• Sigurd Höger

Beilstein J. Org. Chem. 2014, 10, 2783–2788, doi:10.3762/bjoc.10.295

• ]. They can be viewed as shape-persistent arylene–alkynylene macrocycles in which the intraannular spoke system increases the stiffness (persistence length) of the ring. They are non-collapsible monodisperse cyclooligomers with a fixed and predictable conformation, and their side-chain substitution

• guarantees their solubility in organic media. Our previous works on freely rotating chains of rigid rod segments and on shape-persistent macrocycles [6][7] have recently led us to a set of molecular polygons (macrocycles) of discrete sizes and symmetries, e.g., triangles, squares, pentagons, and hexagons [8

• resulting molecule–surface interaction decrease the ability to form a regular pattern, probably (also) due to a lower compound solubility. We observed a similar behavior for phenylene–ethynylene–butadiynylene macrocycles which we compared to their acyclic analoga of identical oligomerization degree [7

Self-assembled monolayers of shape-persistent macrocycles on graphite: interior design and conformational polymorphism

• Joscha Vollmeyer,
• Friederike Eberhagen,
• Sigurd Höger and
• Stefan-S. Jester

Beilstein J. Org. Chem. 2014, 10, 2774–2782, doi:10.3762/bjoc.10.294

• macrocycles of identical backbone structures and extraannular substitution patterns but different (empty, apolar, polar) nanopore fillings are self-assembled at the solid/liquid interface of highly oriented pyrolytic graphite and 1,2,4-trichlorobenzene. Submolecularly resolved images of the resulting two

• macrocycle distances are mainly determined by their size and symmetry. This is an excellent example that the graphite acts as a template for the macrocycle organization independent from their specific interior. Keywords: conformational polymorphism; self-assembled monolayers; shape-persistent macrocycles

• –alkynylene macrocycles are promising candidates as future mounts for functional units. These are separated from each other and cannot interact intermolecularly if the rings are adsorbed in parallel to the substrate. The exterior of the macrocycles can be substituted with alkyl side chains (or their alkoxy

De novo macrolide–glycolipid macrolactone hybrids: Synthesis, structure and antibiotic activity of carbohydrate-fused macrocycles

• Richard T. Desmond,
• Anniefer N. Magpusao,
• Chris Lorenc,
• Jeremy B. Alverson,
• Nigel Priestley and
• Mark W. Peczuh

Beilstein J. Org. Chem. 2014, 10, 2215–2221, doi:10.3762/bjoc.10.229

• of Montana, Missoula, MT 59812, USA 10.3762/bjoc.10.229 Abstract Natural product-like macrocycles were designed as potential antibacterial compounds. The macrocycles featured a D-glucose unit fused into a 12- or 13-member macrolactone. The rings are connected via the C6’ and anomeric (C1’) positions

• of the monosaccharide. The new macrocycles/macrolides were characterized by X-ray crystallography. Their structures showed that, in addition to the ester and alkene units, the dihedral angle about the glycosidic linkage (exo-anomeric effect) influenced the overall shape of the molecules

• macrocycle through the C1’ (glycosidic) and C6’ oxygens. The new macrolides bear a resemblance to sophorolipid lactone 2 and to polyketide macrocycles that contain a tetrahydropyran moiety [20][21][22]. We report on the synthesis, X-ray crystal structures and antibiotic activities of the new compounds

The effect of permodified cyclodextrins encapsulation on the photophysical properties of a polyfluorene with randomly distributed electron-donor and rotaxane electron-acceptor units

• Aurica Farcas,
• Ana-Maria Resmerita,
• Pierre-Henri Aubert,
• Flavian Farcas,
• Iuliana Stoica and
• Anton Airinei

Beilstein J. Org. Chem. 2014, 10, 2145–2156, doi:10.3762/bjoc.10.222

• accurately due to the strong UV absorbance of this solvent. Thus, Ks measurements were performed in CHCl3. The Ks was determined by measuring the change in the absolute optical density (OD) at 314 nm with an increasing concentration of TMS-β-CD or TMS-γ-CD macrocycles and the fitting according to a 1:1 host

• DCM solution of 4a and 4b copolymers suggested no improvements of Φ compared with previously reported results [13], which restrict us to point out a distinctive effect of the rotaxane formation with TMS-β-CD and TMS-γ-CD macrocycles. To further understand Φ results, we also carried out fluorescence

Macrocyclic bis(ureas) as ligands for anion complexation

• Claudia Kretschmer,
• Gertrud Dittmann and
• Johannes Beck

Beilstein J. Org. Chem. 2014, 10, 1834–1839, doi:10.3762/bjoc.10.193

• planar ligand, as was shown by indole-based macrocycles [9]. This ligand system represents a stiff ring of two bis(indole) units connected via two ethynylene groups as linkers. As proven by a crystal structure determination, a chloride ion fits into the cavity bound via four N−H∙∙∙Cl bonds and strong

Improving the reactivity of phenylacetylene macrocycles toward topochemical polymerization by side chains modification

• Simon Rondeau-Gagné,
• Jules Roméo Néabo,
• Maxime Daigle,
• Katy Cantin and
• Jean-François Morin

Beilstein J. Org. Chem. 2014, 10, 1613–1619, doi:10.3762/bjoc.10.167

• -assembly of two new phenylacetylene macrocycle (PAM) organogelators were performed. Polar 2-hydroxyethoxy side chains were incorporated in the inner part of the macrocycles to modify the assembly mode in the gel state. With this modification, it was possible to increase the reactivity of the macrocycles in

• ; phenylacetylene macrocycles; polydiacetylenes; topochemical polymerization; Introduction The self-assembly of molecular building blocks is an increasingly popular method for the preparation of new semiconducting materials. Rational design of building blocks and their assembly using non-covalent interactions can

• . Moreover, subtle changes in the chemical nature of the building blocks can have a dramatic impact on the self-assembly process. This was exemplified in the case of nanotubes obtained from self-assembled butadiyne-containing macrocycles, which stack on top of each other in columnar fashion to give

Design and synthesis of multivalent neoglycoconjugates by click conjugations

• Feiqing Ding,
• Li Ji,
• Ronny William,
• Hua Chai and
• Xue-Wei Liu

Beilstein J. Org. Chem. 2014, 10, 1325–1332, doi:10.3762/bjoc.10.134

• especially versatile for the effective construction of complex glycosylated structures such as clusters, dendrimers, polymers, peptides and macrocycles. In all the cases the triazole ring plays a crucial role in combining divergent units together to establish a complex molecular architecture [23][24][25][26

Homochiral BINOL-based macrocycles with π-electron-rich, electron-withdrawing or extended spacing units as receptors for C₆₀

• Marco Caricato,
• Silvia Díez González,
• Idoia Arandia Ariño and
• Dario Pasini

Beilstein J. Org. Chem. 2014, 10, 1308–1316, doi:10.3762/bjoc.10.132

• several homochiral macrocycles has been achieved by using π-electron-rich, electron-deficient or extended aromatic dicarboxylic acids in combination with an axially-chiral dibenzylic alcohol, derived from enantiomerically-pure BINOL. Two series of cyclic adducts with average molecular D2 and D3 molecular

• cyclic adducts exhibit recognition properties towards C60 in toluene solutions (up to log Ka = 3.2) with variable stoichiometries and variable intensities of the charge-tranfer band upon complexation. Keywords: BINOL; C60; carbon nanomaterials; carbon nanostructures; chirality; macrocycles; sensors

• ; supramolecular chemistry; Introduction Shape persistent macrocycles are carbon-based nanomaterials and are more and more in demand. They enrich the molecular toolkit available to a variety of disciplines, e.g., supramolecular chemistry and materials science [1][2][3][4]. Shape persistency properties are

Substitution effect and effect of axle’s flexibility at (pseudo-)rotaxanes

• Friedrich Malberg,
• Jan Gerit Brandenburg,
• Werner Reckien,
• Oldamur Hollóczki,
• Stefan Grimme and
• Barbara Kirchner

Beilstein J. Org. Chem. 2014, 10, 1299–1307, doi:10.3762/bjoc.10.131

• low-barrier molecular rotary motors with rotaxane architecture [24]. The co-conformational selectivity of two dibenzo-24-crown-8 macrocycles to ammonia binding sites in a [3]rotaxane [25], and the hydrogen bonding strength in polymeric urethane rotaxanes in a mean-field model [26] were investigated by

Synthesis of a sucrose dimer with enone tether; a study on its functionalization

• Zbigniew Pakulski,
• Norbert Gajda,
• Magdalena Jawiczuk,
• Jadwiga Frelek,
• Piotr Cmoch and
• Sławomir Jarosz

Beilstein J. Org. Chem. 2014, 10, 1246–1254, doi:10.3762/bjoc.10.124

• become engaged in the preparation of the analogs of crown and aza-crown ethers with sucrose scaffold. It is based on a selective protection of 1’,2,3,3’,4,4’-hexa-O-benzylsucrose (1) either at the glucose (C-6) [8] or fructose (C-6’) [9] end and further transformations to a variety of macrocycles (2–4

• ; Figure 1). Such receptors exhibit interesting complexing properties towards chiral ammonium salts including amino acids [10][11][12][13][14]. More complex sucrose macrocycles, such as 5, are available, although in rather low yield [15]. In this paper we present an approach to other derivatives containing

• two sucrose units. This type of dimers may be eventually used for the construction of macrocycles by (simple) connecting their C-6’ (fructose) ends. Results and Discussion Coupling of two sugar units can be performed by a number of methods. The best one in our hands was the Wittig-type methodology

Consecutive isocyanide-based multicomponent reactions: synthesis of cyclic pentadepsipeptoids

• Angélica de Fátima S. Barreto,
• Otilie E. Vercillo,
• Ludger A. Wessjohann and
• Carlos Kleber Z. Andrade

Beilstein J. Org. Chem. 2014, 10, 1017–1022, doi:10.3762/bjoc.10.101

• 11a,b. Synthesis of macrocycles 2a-f. Supporting Information Supporting Information File 34: General procedures, NMR and mass spectra of all compounds. Acknowledgements The authors thank the Instituto de Química, Universidade de Brasília, FINEP-CT INFRA nº 970/01, CAPES, CNPq, and DAAD for financial