Local energy decomposition analysis of hydrogen-bonded dimers within a domain-based pair natural orbital coupled cluster study

• Ahmet Altun,
• Frank Neese and
• Giovanni Bistoni

Beilstein J. Org. Chem. 2018, 14, 919–929, doi:10.3762/bjoc.14.79

• modified PBE0 hybrid functional in which the long-range tail contains 75% of LB94 exchange. The shift parameter applied for the bulk potential within this correction was calculated as the sum of the ionization potential and highest occupied molecular orbital (HOMO) energy of each fragment optimized in the

Phosphodiester models for cleavage of nucleic acids

• Satu Mikkola,
• Tuomas Lönnberg and
• Harri Lönnberg

Beilstein J. Org. Chem. 2018, 14, 803–837, doi:10.3762/bjoc.14.68

• case with DNA that is cleaved by an attack of an external nucleophile. Recent hybrid quantum mechanical/effective fragment potential (QM/EEP) calculations on the hydroxide-ion-catalyzed hydrolysis of diethyl phosphate monoanion, however, suggest that the acyclic phosphorane obtained still is an

Heterogeneous Pd catalysts as emulsifiers in Pickering emulsions for integrated multistep synthesis in flow chemistry

• Katharina Hiebler,
• Georg J. Lichtenegger,
• Manuel C. Maier,
• Eun Sung Park,
• Renie Gonzales-Groom,
• Bernard P. Binks and
• Heidrun Gruber-Woelfler

Beilstein J. Org. Chem. 2018, 14, 648–658, doi:10.3762/bjoc.14.52

• interface populated by catalyst particles. They deposited metallic Pd onto carbon nanotube–inorganic oxide hybrid nanoparticles and used them in emulsions for the hydrodeoxygenation of a phenolic compound and the hydrogenation and etherification of an aldehyde. The advantages of such a system include a high

Carbohydrate inhibitors of cholera toxin

• Vajinder Kumar and
• W. Bruce Turnbull

Beilstein J. Org. Chem. 2018, 14, 484–498, doi:10.3762/bjoc.14.34

• the roles of secondary carbohydrate binding sites, will provide new directions for the future development of inhibitors, for example, fucosylated polymers [75], or hybrid inhibitors that can target both the blood group and the GM1 binding pockets. While other emerging, and sophisticated strategies for

Stimuli-responsive oligonucleotides in prodrug-based approaches for gene silencing

• Françoise Debart,
• Christelle Dupouy and
• Jean-Jacques Vasseur

Beilstein J. Org. Chem. 2018, 14, 436–469, doi:10.3762/bjoc.14.32

• siRNA–mRNA hybrid, disturbing the cleavage of mRNA by the RISC. Subsequently, Deiters used the same approach with photo 6-nitropiperonyloxymethyl (NPOM)-photocaged siRNAs synthesized from phosphoramidites of the caged uridine and guanosine ribonucleotides (Scheme 20B) [83]. As previously demonstrated

Synthetic and semi-synthetic approaches to unprotected N-glycan oxazolines

• Antony J. Fairbanks

Beilstein J. Org. Chem. 2018, 14, 416–429, doi:10.3762/bjoc.14.30

• transferases (namely a β(1–2)-GlcNAc transferase, a β(1–4)-galactosyltransferase, and an α(2–6)-sialyltransferase), and the corresponding hybrid N-glycan oxazoline used as a substrate for ENGases [110]. Conclusion N-Glycan oxazolines have found widespread use as activated donor substrates for ENGase enzymes, a

Recent advances on organic blue thermally activated delayed fluorescence (TADF) emitters for organic light-emitting diodes (OLEDs)

• Thanh-Tuân Bui,
• Fabrice Goubard,
• Malika Ibrahim-Ouali,
• Didier Gigmes and
• Frédéric Dumur

Beilstein J. Org. Chem. 2018, 14, 282–308, doi:10.3762/bjoc.14.18

• the fabrication of highly emissive blue OLEDs. Devices fabricated with D6 furnished a maximum EQE of 19.5% and maintained the high EQE of 16% at 1000 cd/m2 with a satisfactory color purity of coordinates (0.16, 0.20). Recently, high-performance TADF based hybrid WOLEDs employing D6 as the blue emitter

• were successfully fabricated [44]. Interestingly, WOLEDs showed excellent device characteristics with an EQE of 23.0%, a current and power efficiency of 51.0 cd/A and 51.7 lm/W, respectively. These performances are among the highest values reported to date for hybrid WOLEDs using a TADF material as the

Fluorogenic PNA probes

• Tirayut Vilaivan

Beilstein J. Org. Chem. 2018, 14, 253–281, doi:10.3762/bjoc.14.17

• binding domain and the stem part consisted of a chimeric PNA–DNA hybrid linked together by a disulfide bond (Figure 4). The chimeric beacon was immobilized to a microtiter plate via a biotin tag and was employed for the detection of PCR amplicons of rDNA from Entamoeba histolytica [41]. The use of PNA

• ]. Interestingly, switching in the opposite direction, when the excimer signal is enhanced upon hybrid formation, was observed in triplex forming double-pyrene-labeled aegPNA probes [69]. For FRET-based PNA beacons, these have so far been investigated in the context of FIT PNA probes (vide infra), which will be

• detection of 16S RNA from a single cell of Escherichia coli [79]. In addition to the detection of DNA and RNA targets, hybrid PNA-peptide beacons were designed for the detection of non-DNA targets, such as proteins (Figure 10A). According to this design, which was simultaneously proposed in 2007 by Seitz

Synthesis and spectroscopic properties of β-meso directly linked porphyrin–corrole hybrid compounds

• Baris Temelli and
• Hilal Kalkan

Beilstein J. Org. Chem. 2018, 14, 187–193, doi:10.3762/bjoc.14.13

• -5,10,15,20-tetraphenylporphyrins with meso-substituted dipyrromethanes. Hybrid compounds have been characterized by 1H NMR, 13C NMR, 2D NMR, UV–vis absorption and fluorescence spectroscopy. Keywords: corrole; hybrid compounds; indium(III) chloride; porphyrin; porphyrinoids; Introduction Porphyrins and

• conjugates, systematic studies on directly linked porphyrin–corrole hybrid structures are limited and there is no report on β-porphyrin, meso-corrole linked hybrids of these conjugates. Zheng et al. synthesized meso–meso directly linked porphyrin–corrole dyads by the condensation reaction of meso-formylated

• -porphyrin, β-corrole-linked hybrid structure described a Suzuki–Miyaura cross-coupling reaction between a β-borylated corrole and meso-bromoporphyrins (Scheme 1D) [37]. Recently, we have successfully synthesized meso–meso and β-meso-linked imine-bridged porphyrin–corrole conjugates and investigated

Polarization spectroscopy methods in the determination of interactions of small molecules with nucleic acids – tutorial

• Tamara Šmidlehner,
• Ivo Piantanida and
• Gennaro Pescitelli

Beilstein J. Org. Chem. 2018, 14, 84–105, doi:10.3762/bjoc.14.5

Aminosugar-based immunomodulator lipid A: synthetic approaches

• Alla Zamyatina

Beilstein J. Org. Chem. 2018, 14, 25–53, doi:10.3762/bjoc.14.3

• owing to enhanced amphiphilicity of the hybrid molecule inflicted by the hydrophobic character of the fluorescent label and the formation of aggregates which resulted in self-quenching. To circumvent these problems, a longer hydrophilic linker and a less hydrophobic fluorescent group were required. An

Nucleophilic dearomatization of 4-aza-6-nitrobenzofuroxan by CH acids in the synthesis of pharmacology-oriented compounds

• Alexey M. Starosotnikov,
• Dmitry V. Shkaev,
• Maxim A. Bastrakov,
• Ivan V. Fedyanin,
• Svyatoslav A. Shevelev and
• Igor L. Dalinger

Beilstein J. Org. Chem. 2017, 13, 2854–2861, doi:10.3762/bjoc.13.277

• heteroaromatics combining several pharmacophoric moieties in the same molecule, interesting from the standpoint of design of novel pharmaceuticals. The work continues our ongoing project on the synthesis of complex hybrid molecules – furoxan-containing potential NO donors [19][20][21][22][23][24]. Results and

Pyrene–nucleobase conjugates: synthesis, oligonucleotide binding and confocal bioimaging studies

• Artur Jabłoński,
• Yannic Fritz,
• Hans-Achim Wagenknecht,
• Rafał Czerwieniec,
• Tytus Bernaś,
• Damian Trzybiński,
• Krzysztof Woźniak and
• Konrad Kowalski

Beilstein J. Org. Chem. 2017, 13, 2521–2534, doi:10.3762/bjoc.13.249

• using the density functional theory (DFT) with the hybrid gradient corrected correlation functional B3LYP [38] and Gaussian-type basis functions 6-311G(d,p) [39]. TD-DFT calculations were performed in the optimized ground state geometry using the same B3LYP functional and basis sets. Five lowest singlet

Solvent-free copper-catalyzed click chemistry for the synthesis of N-heterocyclic hybrids based on quinoline and 1,2,3-triazole

• Martina Tireli,
• Silvija Maračić,
• Stipe Lukin,
• Marina Juribašić Kulcsár,
• Dijana Žilić,
• Mario Cetina,
• Ivan Halasz,
• Silvana Raić-Malić and
• Krunoslav Užarević

Beilstein J. Org. Chem. 2017, 13, 2352–2363, doi:10.3762/bjoc.13.232

• , Figures S11–S14). Computational details. Calculations were carried out using the B3LYP hybrid functional combined with an empirical Grimme’s D3 dispersion correction [55] (B3LYP-D3) implemented in Gaussian 09 [56]. The standard 6-311+G(2d,p) basis set with the ultrafine method was used for C, H, N, F, Cl

Synthesis and application of trifluoroethoxy-substituted phthalocyanines and subphthalocyanines

• Satoru Mori and
• Norio Shibata

Beilstein J. Org. Chem. 2017, 13, 2273–2296, doi:10.3762/bjoc.13.224

• semiconductors [102]. For example, a hybrid compound consisting of phthalocyanine and fullerene 20a causes the transfer of energy from the phthalocyanine unit to the fullerene unit when irradiated by light (Figure 6) [103][104]. However, such energy transfer does not occur in the hybrid of TFEO-ZnPc and

• was obtained at a rate of 68%. This is because the stability of subphthalocyanine and the reactivity of the substitution reaction at the axial position are improved by the introduction of a trifluoroethoxy group. Using this high reactivity of axial substitution, hybrid dyes in which the axial position

• of TFEO-subPc is substituted with fullerene 27 or phthalocyanine 28 intended to construct energy transfer systems have been synthesized (Figure 7). In the previous section, it was explained that the hybrid dye of TFEO-ZnPc and fullerene does not cause energy transfer between units, but in this case

Phosphonic acid: preparation and applications

• Charlotte M. Sevrain,
• Mathieu Berchel,
• Hélène Couthon and
• Paul-Alain Jaffrès

Beilstein J. Org. Chem. 2017, 13, 2186–2213, doi:10.3762/bjoc.13.219

• bone targeting, for the design of supramolecular or hybrid materials, for the functionalization of surfaces, for analytical purposes, for medical imaging or as phosphoantigen. These applications are covering a large panel of research fields including chemistry, biology and physics thus making the

• phosphorus-containing functional groups [2], on specific applications (hybrid materials [3], surface modification [4], oil industry [5]) or dedicated to a family of compounds (e.g., aminophosphonic acids [6], organometallic phosphonic acids [7]). However, no recent review was focused on the different methods

• chemosensor for trinitrotoluene (TNT) [63]. The third important feature of phosphonic acid arises from its coordination properties. Indeed, the three oxygen atoms can be engaged in coordination or iono-covalent bonds. These coordination properties were used to design molecular hybrid materials [64] also

Intramolecular glycosylation

• Xiao G. Jia and
• Alexei V. Demchenko

Beilstein J. Org. Chem. 2017, 13, 2028–2048, doi:10.3762/bjoc.13.201

• attachments that could provide more flexibility in the synthesis of longer oligosaccharides [62][65]. Some representative examples of this general concept include benzyl–silicon tether [72], which is a hybrid approach to xylylene and a regular silicon [59] type of tethering. Another example of a non

• -symmetrical tethering strategy is benzyl–benzoyl hybrid tethering [72] that elaborated on xylylene and phthaloyl tethering approaches discussed above. Thus, this strategy was used in the synthesis of a trisaccharide through reiterative template-assisted synthesis (Scheme 11). Compound 41, wherein the donor

• and acceptor counterparts were subjected to tethering via this rigid hybrid linker, was subjected to the NIS/TfOH-promoted glycosylation. The tether in the resulting disaccharide 42 could then be selectively opened with NaOMe. This leads to liberating only one hydroxy group (at C-3”) that could be

Are boat transition states likely to occur in Cope rearrangements? A DFT study of the biogenesis of germacranes

• José Enrique Barquera-Lozada and
• Gabriel Cuevas

Beilstein J. Org. Chem. 2017, 13, 1969–1976, doi:10.3762/bjoc.13.192

• choice for pericyclic reactions studies [20][56]. In particular, third generation hybrid functionals have improved the description of the potential energy surface and produce very reliable results [57][58][59][60]. Our studies in terpene biogenesis show that these hybrid functionals competes successfully

• with others in the determination of the energetic profile of reaction coordinates [52]. The third-generation hybrid functional improves the description of the energetic barriers with respect to the popular B3LYP functional [61]. Moreover, the B3LYP functional was used in a Cope rearrangement study of

• several germacranes and it was unable to obtain accurate results when the energy differences between germacranes and elemanes were small [62]. All calculations were performed with Gaussian 09 [63]. All the geometries were fully optimized using the DFT hybrid method M06x [57], a functional that is very

Mechanochemical synthesis of thioureas, ureas and guanidines

• Vjekoslav Štrukil

Beilstein J. Org. Chem. 2017, 13, 1828–1849, doi:10.3762/bjoc.13.178

• more nucleophilic in the addition reaction to isocyanates (Scheme 15a). The ability to selectively convert o-pda into non-symmetrical mono-thioureas provided an opportunity to synthesize hybrid urea–thiourea derivatives 37a–d in a one-pot, two-step mechanochemical solvent-free process. After ball

• mechanochemical conditions. a) HOMO−1 contours of mono-thiourea 19b and mono-urea 36. b) Mechanochemical synthesis of hybrid urea-thioureas 37a–d. Synthesis of ureido derivatives 38 and 39 from KOCN and hydrochloride salts of a) L-phenylalanine methyl ester and b) L-threonine(Ot-Bu) methyl ester. c

Block copolymers from ionic liquids for the preparation of thin carbonaceous shells

• Sadaf Hanif,
• Bernd Oschmann,
• Dmitri Spetter,
• Muhammad Nawaz Tahir,
• Wolfgang Tremel and
• Rudolf Zentel

Beilstein J. Org. Chem. 2017, 13, 1693–1701, doi:10.3762/bjoc.13.163

• treatment at 650 °C of the hybrid material enables the conversion of the polymer shell into a carbon shell. The required block copolymers containing the carbonizable block and the anchoring block, which can bind onto the nanoparticle surface, was synthesized by RAFT polymerization as described in Figure 1b

• alcohol, which was used as a solvent for the synthesis. As a rough estimate for the weight loss of the coordinated polymer only the weight loss above 240 °C is considered to 20%. For the carbonization process the hybrid material was pyrolyzed in argon atmosphere and heated up to 650 °C. The application of

• addition, a macroscopic color change of the hybrid material can be observed. As-synthesized TiO2 nanoparticles coated with the block copolymer looks brown due to the bound catechol. However, the color turns black after the pyrolysis (Figure 4d) indicating the presence of carbon material. This was proven by

Encaging palladium(0) in layered double hydroxide: A sustainable catalyst for solvent-free and ligand-free Heck reaction in a ball mill

• Wei Shi,
• Jingbo Yu,
• Zhijiang Jiang,
• Qiaoling Shao and
• Weike Su

Beilstein J. Org. Chem. 2017, 13, 1661–1668, doi:10.3762/bjoc.13.160

• hybrid LDHs were then reduced by hydrazine hydrate (N2H4·H2O) to obtain the Pd catalyst supported on MgAl-LDHs (Pd/MgAl-LDHs). The as-prepared Pd/MgAl-LDH catalyst was further applied in representative cross-coupling Heck reactions under HSBM conditions (Scheme 1) by using a planetary ball mill

The chemistry and biology of mycolactones

• Matthias Gehringer and
• Karl-Heinz Altmann

Beilstein J. Org. Chem. 2017, 13, 1596–1660, doi:10.3762/bjoc.13.159

2-Methyl-2,4-pentanediol (MPD) boosts as detergent-substitute the performance of ß-barrel hybrid catalyst for phenylacetylene polymerization

• Julia Kinzel,
• Daniel F. Sauer,
• Marco Bocola,
• Marcus Arlt,
• Tayebeh Mirzaei Garakani,
• Andreas Thiel,
• Klaus Beckerle,
• Tino Polen,
• Jun Okuda and
• Ulrich Schwaneberg

Beilstein J. Org. Chem. 2017, 13, 1498–1506, doi:10.3762/bjoc.13.148

• over micelle-forming detergents is demonstrated in the polymerization of phenylacetylene, showing a ten-fold increase in yield and increased molecular weights. Keywords: amphiphilic molecule 2-methyl-2,4-pentanediol; hybrid catalyst; phenylacetylene polymerization; refolding agents; transmembrane

• the β-barrel membrane channel protein FhuA WT co-crystallized with the detergent n-octyl-2-hydroxyethyl sulfoxide [24]. The N-terminal cork domain (residue 1-160) blocking the channel was removed. The amino acid exchanges of the hybrid catalyst model FhuA ΔCVFtev, namely cysteine at position 545

Mechanochemistry-assisted synthesis of hierarchical porous carbons applied as supercapacitors

• Desirée Leistenschneider,
• Nicolas Jäckel,
• Felix Hippauf,
• Volker Presser and
• Lars Borchardt

Beilstein J. Org. Chem. 2017, 13, 1332–1341, doi:10.3762/bjoc.13.130

• distributions were achieved by applying the hybrid QSDFT model for slit-shaped, cylindrical and spherical pores at −196 °C. The micropore volume was calculated from the cumulative QSDFT pore volume data at 2 nm. Energy dispersive X-ray (EDX) analyses were performed with a SU8020 from Hitachi at an acceleration

Correlation of surface pressure and hue of planarizable push–pull chromophores at the air/water interface

• Frederik Neuhaus,
• Fabio Zobi,
• Gerald Brezesinski,
• Marta Dal Molin,
• Stefan Matile and
• Andreas Zumbuehl

Beilstein J. Org. Chem. 2017, 13, 1099–1105, doi:10.3762/bjoc.13.109

• . Computational simulations Geometry optimization, as well as frequency calculations for the flipper mechanophore, were performed in the gas phase at the density functional level of theory with the Gaussian 03 program package [35] using the hybrid B3LYP functional [36] in conjunction with the LanL2DZ basis set