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Search for "structural features" in Full Text gives 223 result(s) in Beilstein Journal of Organic Chemistry. Showing first 200.
Evaluation of dispersion type metal···π arene interaction in arylbismuth compounds – an experimental and theoretical study
Beilstein J. Org. Chem. 2018, 14, 2125–2145, doi:10.3762/bjoc.14.187
- , Professur Anorganische Chemie, 09107 Chemnitz, Germany 10.3762/bjoc.14.187 Abstract The dispersion type Bi···π arene interaction is one of the important structural features in the assembly process of arylbismuth compounds. Several triarylbismuth compounds and polymorphs are discussed and compared based on
- interactions between different structural features balance in order to stabilize molecular arrangements present in the crystal structure. Furthermore, the computational results allow to group this class of compounds into the range of heavy main group element compounds which have been characterized as
- interactions (Bi···π, π···π or C–H···π) is observed and thus leads to different structural features in the solid state (Table 1). Here the question arises how important and how large these interactions are and whether any type of interaction is dominating. For this reason computational studies have been
Water-soluble SNS cationic palladium(II) complexes and their Suzuki–Miyaura cross-coupling reactions in aqueous medium
Beilstein J. Org. Chem. 2018, 14, 1859–1870, doi:10.3762/bjoc.14.160
- nature of the backbone on the catalytic activity of the SNS pincer Pd(II) complexes. In the future, efforts to fine tune the electronic and structural features of the thiophenyl and pyridinyl groups will be carried out in order to enable the catalysts to activate aryl chlorides, possessing electron
Enzyme-free genetic copying of DNA and RNA sequences
Beilstein J. Org. Chem. 2018, 14, 603–617, doi:10.3762/bjoc.14.47
- (kcov/khydr), when reacting with an RNA primer. It will not be trivial to find such a leaving group, as the nucleophilicity of alcohols is quite similar to that of water, so that it is difficult to utilize the chemoselectivity toward reaction partners with different softness, pKa, or other structural
- features. Copying on solid support As mentioned above, one option to avoid stalling of primer extension reactions is to perform them on solid support. For RNA, the immobilization of the primer–template duplex was achieved by employing a biotinylated capture strand that was bound to streptavidin-coated
Carbohydrate inhibitors of cholera toxin
Beilstein J. Org. Chem. 2018, 14, 484–498, doi:10.3762/bjoc.14.34
- particular emphasis on exploiting the multivalency of the toxin to enhance activity. In this review we introduce the structural features of the toxin that have guided the design of diverse inhibitors and summarise recent developments in the field. Keywords: carbohydrate; cholera; multivalency; toxin
5-Aminopyrazole as precursor in design and synthesis of fused pyrazoloazines
Beilstein J. Org. Chem. 2018, 14, 203–242, doi:10.3762/bjoc.14.15
Aminosugar-based immunomodulator lipid A: synthetic approaches
Beilstein J. Org. Chem. 2018, 14, 25–53, doi:10.3762/bjoc.14.3
- isolates obtained from bacterial cultures as well as possible contamination with other pro-inflammatory bacterial components makes it difficult to obtain unambiguous immunobiological data correlating specific structural features of lipid A with its endotoxic activity. Advanced understanding of the
- structural homologs having a variable number of the long-chain acyl residues of different chain lengths. The structural heterogeneity of lipid A preparations obtained through LPS isolation from bacterial cultures makes it difficult to get an unbiased correlation of specific structural features of lipid A and
- dependent manner via the action of an oxidase located in the outer membrane [113][114]. The unique Rhizobium lipid A lacks the structural features which are necessary for the TLR4-mediated stimulation of the innate immune system in animals. This might conceivably help bacteroids to evade the innate immune
Binding abilities of a chiral calix[4]resorcinarene: a polarimetric investigation on a complex case of study
Beilstein J. Org. Chem. 2017, 13, 2698–2709, doi:10.3762/bjoc.13.268
- known from the literature as NMR shift reagent able to perform chiral recognition [24][25][26][27]. Guests 1–12 were selected for their diverse structural features. We considered both neutral and ionic species, in particular aliphatic and aromatic cations of different size and hydrophobic character
- M−1). Owing to the diverse behaviours observed, a comparison between the different guests is not straightforward, and a full rationalization of the outcome of their structural features on the binding equilibrium is not simple. Nevertheless, the data allow some further interesting observations. In
Development of a fluorogenic small substrate for dipeptidyl peptidase-4
Beilstein J. Org. Chem. 2017, 13, 2690–2697, doi:10.3762/bjoc.13.267
- different, ideally, non-fluorescence and intensive fluorescence, respectively. On the basis of the structural features of 1, we expected that its fluorescence would disappear as a result of peptide derivatization of the amino group, because electron donation by the amino group would be attenuated and the
Pyrene–nucleobase conjugates: synthesis, oligonucleotide binding and confocal bioimaging studies
Beilstein J. Org. Chem. 2017, 13, 2521–2534, doi:10.3762/bjoc.13.249
- are characterized by structural features originated from their components: a planar pyrenyl group and the heterocyclic nucleobase unit. While the pyrenyl group is known to act as intercalator [8][9], the nucleobases are known to self-assemble via a network of hydrogen bonds [16][34]. Our aim was to
Synthesis of ergostane-type brassinosteroids with modifications in ring A
Beilstein J. Org. Chem. 2017, 13, 2326–2331, doi:10.3762/bjoc.13.229
- -, 3-keto-, 3α- and 3β-hydroxy-, 2α-hydroxy-3-keto-) which are characteristic for biosynthetic precursors/metabolites of BS. The 2α,3α-diol function of ergostane BS was shown to be transformable into the required functionalities in only two to four standard chemical transformations. Structural features
Novel approach to hydroxy-group-containing porous organic polymers from bisphenol A
Beilstein J. Org. Chem. 2017, 13, 2131–2137, doi:10.3762/bjoc.13.211
- Information File 1), it can be found that the 13C chemical shifts of these polymers are similar. It is reasonable considering the structural features of these polymers. Typically, taking the spectrum of PPOP-1 for example, two major resonances at 127 and 140 ppm are assigned to the unsubstituted phenyl carbon
Difunctionalization of alkenes with iodine and tert-butyl hydroperoxide (TBHP) at room temperature for the synthesis of 1-(tert-butylperoxy)-2-iodoethanes
Beilstein J. Org. Chem. 2017, 13, 2023–2027, doi:10.3762/bjoc.13.200
- unique structural features, which make them available to serve as starting materials for a wide range of organic oxidations to access other oxygenated products [36]. Results and Discussion A pilot reaction setup comprised of styrene (1a, 208 mg, 2.0 mmol) in the presence of I2 (1.0 equiv), TBHP (2.0
Mechanochemical synthesis of thioureas, ureas and guanidines
Beilstein J. Org. Chem. 2017, 13, 1828–1849, doi:10.3762/bjoc.13.178
- , mechanochemistry has been demonstrated as an effective tool in reaction discovery, with emphasis on the reactivity differences in solution and in the solid state. These three classes of organic compounds share some structural features which are reflected in their physical and chemical properties, important for
The chemistry and biology of mycolactones
Beilstein J. Org. Chem. 2017, 13, 1596–1660, doi:10.3762/bjoc.13.159
- toxin. III. Total synthesis of mycolactones The fascinating biology and the challenging structural features of mycolactones have attracted significant interest from research groups worldwide with a focus on natural product synthesis. In this chapter the synthetic work on mycolactones that has been
Glycoscience@Synchrotron: Synchrotron radiation applied to structural glycoscience
Beilstein J. Org. Chem. 2017, 13, 1145–1167, doi:10.3762/bjoc.13.114
- , the double helices have a radial orientation, and are perpendicular to the surface of the granule. At the resolution of these ultra-structural features (10 µm) there is no discontinuity of orientation, i.e., no disclination of orientation. Between 10 µm steps, the change of the direction of the double
Cyclodextrins tethered with oligolactides – green synthesis and structural assessment
Beilstein J. Org. Chem. 2017, 13, 779–792, doi:10.3762/bjoc.13.77
- characterization should be performed in order to fully describe such systems. We showed that understanding of molecular level structural features of such complex mixtures (free CDs, homopolymers, CD-oligoesters) have to take into consideration the mass spectrometry methods in direct correlation with the NMR
Inclusion complexes of β-cyclodextrin with tricyclic drugs: an X-ray diffraction, NMR and molecular dynamics study
Beilstein J. Org. Chem. 2017, 13, 714–719, doi:10.3762/bjoc.13.70
- , consistent with the 1:1 host–guest stoichiometry. Some important structural features of the inclusion complexes of 1 and 2 can be outlined by the analysis of the 1H NMR spectra: the spectrum of 1 shows that the AB quartet assigned to H9–H10 spin system is split into two AB quartets on passing from pure 1 to
- compound 1. Compounds 1 and 2 are not planar and the exocyclic double bond prevents the free rotation of the side chain with respect to the ring system. Consequently, 1 and 2 show inherent chirality [9] as lacking of symmetry elements. The main purpose of the work is the comparison of the structural
- features obtained in the solid state and in D2O solution by X-ray diffraction and NMR spectroscopy, respectively. The dynamic behaviour of the examined systems is simulated by MD runs of the complexes with explicit water. Suitable structural descriptors thus obtained as time averages are then compared to
Secondary metabolome and its defensive role in the aeolidoidean Phyllodesmium longicirrum, (Gastropoda, Heterobranchia, Nudibranchia)
Beilstein J. Org. Chem. 2017, 13, 502–519, doi:10.3762/bjoc.13.50
- 1H,1H spin system required heteronuclear long range correlations for the elucidation of the remaining structural features and the closure of the cembrane ring. Methylene group CH2-3 exhibited HMBC correlations with resonances of the keto at C-2, sp2 quaternary carbon C-4 and tertiary carbon C-5 and
Structure–efficiency relationships of cyclodextrin scavengers in the hydrolytic degradation of organophosphorus compounds
Beilstein J. Org. Chem. 2017, 13, 417–427, doi:10.3762/bjoc.13.45
- pesticides and soman was evaluated. Some structural features of the scavengers could be identified as the key elements in charge to accelerate the decontamination of organophosphorus compounds: (1) the degradation kinetics of organophosphorus constituents is dependent on their affinity for the cyclodextrin
Efficient access to β-vinylporphyrin derivatives via palladium cross coupling of β-bromoporphyrins with N-tosylhydrazones
Beilstein J. Org. Chem. 2017, 13, 195–202, doi:10.3762/bjoc.13.22
- diversity of structural features that can be induced in the porphyrin structure [14][15][16]. Alkenyl-type moieties are examples of versatile functional groups which are present in several biologically active natural porphyrin derivatives or are substituents that can be introduced into the macrocycles
Dynamics and interactions of ibuprofen in cyclodextrin nanosponges by solid-state NMR spectroscopy
Beilstein J. Org. Chem. 2017, 13, 182–194, doi:10.3762/bjoc.13.21
- on passing from the empty CDNS to the drug-loaded CDNS, thus showing that the drug encapsulation can be seen as the formation of a real supramolecular aggregate rather than a conglomerate of two solid components. Finally, the structural features obtained from the different solid-state NMR approaches
Phosphated cyclodextrins as water-soluble chiral NMR solvating agents for cationic compounds
Beilstein J. Org. Chem. 2017, 13, 43–53, doi:10.3762/bjoc.13.6
- structural features are examined and enantiomeric differentiation obtained with P-CDs is compared to prior results acquired with CM-CDs. Results and Discussion Thirty-three substrates including α-methylbenzylamine (1), N,α-dimethylbenzylamine (2), N,N-dimethyl-1-phenethylamine (3), N-allyl-α
Supramolecular frameworks based on [60]fullerene hexakisadducts
Beilstein J. Org. Chem. 2017, 13, 1–9, doi:10.3762/bjoc.13.1
- the spacer length, the solvent-filled pore systems in the solid-state structures have been tuned and structural features such as porosity of the materials have been investigated by PXRD, TGA analysis and sorption studies. Results and Discussion Recently, we reported on the synthesis and solid-state
Synthesis of acylhydrazino-peptomers, a new class of peptidomimetics, by consecutive Ugi and hydrazino-Ugi reactions
Beilstein J. Org. Chem. 2016, 12, 2865–2872, doi:10.3762/bjoc.12.285
- allows an easy access to highly functionalized peptomers in good yields and a reduced number of steps. This method may also be employed to obtain new classes of peptidomimetics with potential biological activity. Structural features of (a) peptide, (b) peptoid, (c) peptomer, (d) azapeptide, (e
New approaches to organocatalysis based on C–H and C–X bonding for electrophilic substrate activation
Beilstein J. Org. Chem. 2016, 12, 2834–2848, doi:10.3762/bjoc.12.283
- attempting to elucidate the nature of halogen complexes have emerged since then; however, the structural features of these interactions were unclear until the work of Mulliken who proposed the formation of donor–acceptor complexes [65][66] and Odd Hassel who conducted crystallographic studies of bromine
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