Fabrication, characterization and adsorption properties of cucurbit[7]uril-functionalized polycaprolactone electrospun nanofibrous membranes

• Changzhong Chen,
• Fengbo Liu,
• Xiongzhi Zhang,
• Zhiyong Zhao and
• Simin Liu

Beilstein J. Org. Chem. 2019, 15, 992–999, doi:10.3762/bjoc.15.97

• investigated in this work (Scheme 1). Results and Discussion As a common biodegradable polymer, PCL has been frequently reported as the fiber template material for the fabrication of electrospun nanofibers. Various common solvents such as acetone, dichloromethane, chloroform, tetrahydrofuran, DMF or their

Heck- and Suzuki-coupling approaches to novel hydroquinone inhibitors of calcium ATPase

• Robert J. Kempton,
• Taylor A. Kidd-Kautz,
• Soizic Laurenceau and
• Stefan Paula

Beilstein J. Org. Chem. 2019, 15, 971–975, doi:10.3762/bjoc.15.94

• Abstract In this study, we explored Heck- and Suzuki-coupling methodology to modify the template 2,5-di-tert-butylhydroquinone (BHQ, 2), an inhibitor of the enzyme sarco/endoplasmic reticulum calcium ATPase (SERCA). We found that by utilizing Suzuki coupling, we could successfully attach a six-carbon

• complex BHQ template. Furthermore, using a BHQ template could be a valuable alternative to TG-based compounds, should the latter encounter problems such as low bioavailability or drug resistance. The first step towards the development of BHQ-based compounds of therapeutic value is the establishment of a

• with Boc groups present [23]. Conclusion Using Heck- and Suzuki-coupling reactions, we have developed a synthetic route that provides a BHQ template tethered to a leucine residue (14). Similar to its TG-based counterparts, 14 is an active SERCA inhibitor, which is a requirement for its potential use as

Catalytic asymmetric oxo-Diels–Alder reactions with chiral atropisomeric biphenyl diols

• Chi-Tung Yeung,
• Wesley Ting Kwok Chan,
• Wai-Sum Lo,
• Ga-Lai Law and
• Wing-Tak Wong

Beilstein J. Org. Chem. 2019, 15, 955–962, doi:10.3762/bjoc.15.92

• library of aldehydes (aromatic: 97–99% ee; aliphatic: 84–98% ee) [28]. Thereafter, many different kinds of hydrogen bonding-based organocatalysts have been developed for oxo-DA reactions [29][30][31][32][33][34][35]. One kind of organocatalyst in particular, which is based on an oxazoline template with

Synthesis of (macro)heterocycles by consecutive/repetitive isocyanide-based multicomponent reactions

• Angélica de Fátima S. Barreto and
• Carlos Kleber Z. Andrade

Beilstein J. Org. Chem. 2019, 15, 906–930, doi:10.3762/bjoc.15.88

• for the synthesis of molecular cages was described [50]. The approach was based on macromulticycle connectivities through bridgeheads. For the macrocyclization reaction, metal-template-driven and dilution conditions were used. These conditions allowed one-pot synthesis including aryl, heterocyclic

• , polyether, peptidic and steroidal tethers. Scheme 33 shows a template-driven approach to macrotricycles 170, which were obtained from preformed diimine 168 and addition of diacid 169 and diisocyanide 130 as building blocks. Conclusion Based on the many examples shown herein, one can conclude that the

• during the bidirectional macrocyclization [48]. MiBs based on the Passerini-3CR for the synthesis of macrolactones [49]. Template-driven approach for the synthesis of macrotricycles 170 [50]. Acknowledgements CNPq, CAPES and the Universidade de Brasília are acknowledged for financial support.

Mechanochemistry of supramolecules

• Anima Bose and
• Prasenjit Mal

Beilstein J. Org. Chem. 2019, 15, 881–900, doi:10.3762/bjoc.15.86

• ][42]. Review Self-assembly During a metal-directed self-assembly process, the coordination geometry and coordination number at the metal center plays a central role in creating a self-assembled system. In 1962, Busch and coworker first demonstrated the concept of the template effect by choosing a

• suitable metal ion to control a self-assembly process [43][44]. The template enforces the assembly of the smaller units around it in a distinct and organized way favoring the formation of a particular product from a mixture with multiple possibilities [45]. Therefore, the concept of selection of

• interactions of alternating hydrophilic and hydrophobic units in the peptide chains played the vital role in the system. Friščić and Aav with co-workers reported the first solvent-free mechanochemical synthesis of hemicucurbiturils [90] through the anion template effect of dynamic covalent chemistry [47][91

Synthesis of nonracemic hydroxyglutamic acids

• Dorota G. Piotrowska,
• Iwona E. Głowacka,
• Andrzej E. Wróblewski and
• Liwia Lubowiecka

Beilstein J. Org. Chem. 2019, 15, 236–255, doi:10.3762/bjoc.15.22

• chiral template for the synthesis of (2S,3R)-2 since configurations at C3 and C4 in the hexose are retained in the target compound. The disclosed strategy relied on prior transformation of D-glucose into azidofuranoside 57 [66] and next to acid 58. Homologation of acid 58 was accomplished by the Arndt

Thermophilic phosphoribosyltransferases Thermus thermophilus HB27 in nucleotide synthesis

• Ilja V. Fateev,
• Ekaterina V. Sinitsina,
• Aiguzel U. Bikanasova,
• Maria A. Kostromina,
• Elena S. Tuzova,
• Larisa V. Esipova,
• Tatiana I. Muravyova,
• Alexei L. Kayushin,
• Irina D. Konstantinova and
• Roman S. Esipov

Beilstein J. Org. Chem. 2018, 14, 3098–3105, doi:10.3762/bjoc.14.289

• a standard. Protein purity was determined by electrophoresis in a polyacrylamide gel under denaturing conditions [18]. Cloning and creation of producer strain: Genes TT_RS08985 and TT_RS06315, encoding TthHPRT and TthAPRT, respectively, were amplified on the genomic DNA template of the T

Repurposing the anticancer drug cisplatin with the aim of developing novel Pseudomonas aeruginosa infection control agents

• Mingjun Yuan,
• Song Lin Chua,
• Yang Liu,
• Daniela I. Drautz-Moses,
• Joey Kuok Hoong Yam,
• Thet Tun Aung,
• Roger W. Beuerman,
• May Margarette Santillan Salido,
• Stephan C. Schuster,
• Choon-Hong Tan,
• Michael Givskov,
• Liang Yang and
• Thomas E. Nielsen

Beilstein J. Org. Chem. 2018, 14, 3059–3069, doi:10.3762/bjoc.14.284

• transcriptase PCR (qRT-PCR) was performed using a two-step method. First-strand cDNA was synthesized from total RNA using SuperScript III First-Strand Synthesis SuperMix kit (Cat. No. 18080-400, Invitrogen). The cDNA was used as a template for qRT-PCR with a SYBR Select Master Mix kit (Cat. No. 4472953, Applied

Protein–protein interactions in bacteria: a promising and challenging avenue towards the discovery of new antibiotics

• Laura Carro

Beilstein J. Org. Chem. 2018, 14, 2881–2896, doi:10.3762/bjoc.14.267

• antimicrobial molecules are presented below. β-Sliding clamp Sliding clamps are prokaryotic ring-shaped proteins that secure DNA polymerases to the DNA template and slide along the double helix, enabling enzyme activity at a specific region of the DNA and increasing the rapid and processive DNA synthesis [52

• antibacterial effects. In addition to small molecules, peptides have also been investigated as disruptors of protein–protein interactions in the sliding clamp. A structure-based approach, using the natural pentapeptide QL(S/D)LF (8, Figure 3) as a template, led to the identification of the short peptide P6 (16

•  8) as a template, Rush et al. applied a shape-comparison program (rapid overlay of chemical structures, ROCS). This study led to the identification of three lead-like scaffolds among which compound 38 (Figure 8) was the most active with a Kd of 73.9 μM. In spite of the fact that this molecule was

Synthesis of unnatural α-amino esters using ethyl nitroacetate and condensation or cycloaddition reactions

• Glwadys Gagnot,
• Vincent Hervin,
• Eloi P. Coutant,
• Sarah Desmons,
• Racha Baatallah,
• Victor Monnot and
• Yves L. Janin

Beilstein J. Org. Chem. 2018, 14, 2846–2852, doi:10.3762/bjoc.14.263

• de la Recherche Scientifique, 28 rue du Dr. Roux, 75724 Paris Cedex 15, France Université Paris Descartes, Sorbonne Paris Cité, 12 rue de l'École de Médecine, 75006 Paris, France 10.3762/bjoc.14.263 Abstract We report here on the use of ethyl nitroacetate as a glycine template to produce α-amino

Tetrathiafulvalene – a redox-switchable building block to control motion in mechanically interlocked molecules

• Hendrik V. Schröder and
• Christoph A. Schalley

Beilstein J. Org. Chem. 2018, 14, 2163–2185, doi:10.3762/bjoc.14.190

• supramolecular chemistry [28] and for the construction of MIMs [29], the good π-donor properties of TTF are frequently used to template donor–acceptor complexes with π-electron deficient macrocycles. If TTF undergoes oxidation, the π-donating effect decreases, whereas the TTF2+ dication can be considered as a π

• -yielding statistical synthesis to efficient template-controlled synthesis, rotaxanes have become the workhorse of MIMs in the last three decades. Regarding their use as molecular devices, three types of motions can be potentially controlled in rotaxanes: pirouetting of the wheel around the axle

• (6) ring threaded onto a water-soluble axle [80]. The rotaxane was synthesized in 23% yield by a template/capping strategy where one stopper is attached using copper-catalyzed azide–alkyne click chemistry after the formation of the precursor pseudorotaxane. Due to the hydrophobic effect, the neutral

Efficient catenane synthesis by cucurbit[6]uril-mediated azide–alkyne cycloaddition

• Antony Wing Hung Ng,
• Chi-Chung Yee,
• Kai Wang and
• Ho Yu Au-Yeung

Beilstein J. Org. Chem. 2018, 14, 1846–1853, doi:10.3762/bjoc.14.158

• macrocycles will be ensured. One example is the use of an active metal template, in which the macrocyclization is mediated by the metal ion inside the cavity of a metal-coordinating macrocycle [20]. Cucurbit[6]uril (CB[6]) has also been demonstrated to bind to ammonium-containing azides and alkynes and to

Graphitic carbon nitride prepared from urea as a photocatalyst for visible-light carbon dioxide reduction with the aid of a mononuclear ruthenium(II) complex

• Kazuhiko Maeda,
• Daehyeon An,
• Ryo Kuriki,
• Daling Lu and
• Osamu Ishitani

Beilstein J. Org. Chem. 2018, 14, 1806–1812, doi:10.3762/bjoc.14.153

• reactions [21][22]. Apart from mpg-C3N4 that is usually prepared by a hard-template method with multistep procedures [9][23], g-C3N4 having a relatively higher surface area can be readily prepared by heating urea, which is an inexpensive and readily available precursor, in air [14][24]. In fact, the urea

Natural and redesigned wasp venom peptides with selective antitumoral activity

• Marcelo D. T. Torres,
• Gislaine P. Andrade,
• Roseli H. Sato,
• Cibele N. Pedron,
• Tania M. Manieri,
• Giselle Cerchiaro,
• Anderson O. Ribeiro,
• Cesar de la Fuente-Nunez and
• Vani X. Oliveira Jr.

Beilstein J. Org. Chem. 2018, 14, 1693–1703, doi:10.3762/bjoc.14.144

• [9][10]. The two Dec-NH2 analogs designed to fit a leucine zipper (LZ) template [25][26] presented the lowest hemolytic activity against red blood cells and maintained the antimicrobial activity of the parent template molecule vs Gram-positive bacteria, Gram-negative bacteria, and fungi. The authors

• investigated Dec-NH2, its LZ template and single/double substituted derivatives for their ability to selectively kill MCF-7 breast cancer cells. Results and Discussion Peptide design, chemical synthesis, purification and physicochemical analyses Dec-NH2 is a cationic α-helical antimicrobial and antiparasitic

• peptide [9][10][24] that is rich in Leu residues. We took into account these characteristics and designed two of the analogs proposed here using to a leucine zipper template, on which Leu residues were present in both ‘a’ and ‘d’ positions of the heptad sequence. This template design favors helical

On the design principles of peptide–drug conjugates for targeted drug delivery to the malignant tumor site

• Eirinaios I. Vrettos,
• Gábor Mező and
• Andreas G. Tzakos

Beilstein J. Org. Chem. 2018, 14, 930–954, doi:10.3762/bjoc.14.80

Recent advances in synthetic approaches for medicinal chemistry of C-nucleosides

• Kartik Temburnikar and
• Katherine L. Seley-Radtke

Beilstein J. Org. Chem. 2018, 14, 772–785, doi:10.3762/bjoc.14.65

• that the triphosphate of 24 (24-TP) was incorporated opposite U and C of an RNA template by the influenza polymerase [74]. These experiments indicate that the H-bonding motifs of 24 allow it to mimic both A and G (Figure 10A) [74]. Despite the mis-incorporation, an unmodified sugar moiety may not

Enzyme-free genetic copying of DNA and RNA sequences

• Marilyne Sosson and
• Clemens Richert

Beilstein J. Org. Chem. 2018, 14, 603–617, doi:10.3762/bjoc.14.47

• successful modeling of the reaction, the strength of the template effect, the inhibitory effect of spent monomers, and the rate constants of the chemical steps have to be determined experimentally. While challenges remain for the high fidelity copying of long stretches of DNA or RNA, the available data

• examples can also be found in the literature of the 1960s [12]. The early monomer-based work on copying RNA focused on oligomerization of nucleotides on homosequences as templates [13][14]. The best results were observed for poly(C) as template, the 2-methylimidazolide of guanosine as activated monomer

• reaction that was made since our earlier account on the topic [22]. Other reviews that cover enzyme-free copying exist, and the reader is directed to these papers for a more in-depth treatment of issues only touched upon in our account [13][23][24][25]. Review Template effect and sequence dependence One

Fluorogenic PNA probes

• Tirayut Vilaivan

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

• nucleic acid scaffold or template, which allows the two dyes to optically interact, such as by FRET or excimer formation (Figure 11) [83]. In principle, the hybridization of two very short PNA probes should offer a better selectivity than a single longer PNA probe. The relative positions of the two labels

• concentrations typically required for detection of the target molecules (nanomolar range or below). However, binding of the probes at adjacent positions on the same DNA or RNA template increases the local concentration of the probes so that they can readily react, resulting in creating and/or breaking one or

• (Figure 13) [90]. Signal amplification is also possible in the former case provided that the reaction was designed to give a ligated product that does not bind too tightly to the template, for example by using isocysteine-mediated native chemical ligation to provide a ligated PNA with a sub-optimal

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

• ligand chromophores form an aggregate, with a well-defined supramolecular chirality. In this case, the ECD can still be said to be “induced” by the polynucleotide because it acts as a chiral template. An unambiguous interpretation of exciton-coupled bisignate ICD bands is not simple due to many different

Synthetic mRNA capping

• Fabian Muttach,
• Nils Muthmann and
• Andrea Rentmeister

Beilstein J. Org. Chem. 2017, 13, 2819–2832, doi:10.3762/bjoc.13.274

• ], NAD-capped RNAs [23][24], 3'-dephospho-CoA linked RNA [25] or methylphosphate capping [26][27] we refer to the indicated articles. Review Enzymatic preparation of capped mRNA Enzymatic preparation of capped mRNA is based on in vitro transcription (IVT) of a DNA template. While RNA synthesized via

• ] can be used. Primase incorporates cap analogues exclusively in their correct orientation. Normally, gene 4 primase from the T7 phage produces short RNAs with the sequence pppAC from a DNA template. Matsuo et al. observed that GpppA or m7GpppA can be incorporated as efficiently as ATP as the first

• of the replicative DNA polymerase from Thermococcus gorgonarius (Tgo) into a DNA-dependent RNA polymerase (termed TGK) enabled production of up to 1,700 nt long RNAs from a ssDNA template and an RNA primer [119]. The primer-dependent RNA synthesis obviates the need to initiate RNA synthesis with pppG

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

• solution. In respect to the complementary oligothymidine T10 template in water, compounds 3 and 5 both show a self-assembling behavior according to canonical base–base pairing. However, in buffer solution, derivative 5 was much more effective than 3 in binding to the T10 template. Furthermore the adenine

• derivative 5 binds to the double-stranded (dA)10–T10 template with a self-assembly ratio of 112%. Such a high value of a self-assembly ratio can be rationalized by a triple-helix-like binding, intercalation, or a mixture of both. Remarkably, compound 5 also shows dual staining pattern in living HeLa cells

• detecting markers [14], as fluorescent DNA probes [15], non-covalent binders to canonical oligonucleotide templates [16], and antiviral agents [17][18]. Notably, pyrene excimer formation in DNA template assemblies is much less efficient than in normal pyrene conjugates due to the helical twist between

Synthesis of 2-aminosuberic acid derivatives as components of some histone deacetylase inhibiting cyclic tetrapeptides

• Shital Kumar Chattopadhyay,
• Suman Sil and
• Jyoti Prasad Mukherjee

Beilstein J. Org. Chem. 2017, 13, 2153–2156, doi:10.3762/bjoc.13.214

• of peptidomimetics. A cross-metathesis reaction has been utilized to create the diversification on the template 11 in order to obtain orthogonally protected Asu derivatives. Moreover, the Asu derivative 15a has been demonstrated to be useful in the preparation of a plethora of HDAC inhibitors [34

Intramolecular glycosylation

• Xiao G. Jia and
• Alexei V. Demchenko

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

• introduced by Kusumoto et al. [46], however, this term was coined by the same group much later [51]. We adopt this term to generally refer to this concept, which in other applications was also named “intramolecular glycosylation of prearranged glycosides” by Ziegler [52][53], “template-directed cyclo

• category was extensively studied and applied to a variety of sugar series and targets [58][73][74]. Phthaloyl and related tethers Phthaloyl tethering was also introduced by Ziegler [53] and practically concomitantly by Valverde et al. [54] as “template-directed cyclo-glycosylation.” In the latter

• that affected the removal of the template and all benzyl protecting groups followed by acetylation of the resulting hydroxy groups. Peptide tether/template Short peptide chains have also been investigated as templates for glycosylation. The general underpinning idea is to streamline the oligosaccharide

A recursive microfluidic platform to explore the emergence of chemical evolution

• David Doran,
• Marc Rodriguez-Garcia,
• Rebecca Turk-MacLeod,
• Geoffrey J. T. Cooper and
• Leroy Cronin

Beilstein J. Org. Chem. 2017, 13, 1702–1709, doi:10.3762/bjoc.13.164

• autocatalytic networks that reproduce, with more or less the same stoichiometry, all functionally active components of their heterogeneous chemical mixtures. Such systems could easily exist outside the boundaries of known biology, and perhaps may not even require a template-driven genetic polymer to reproduce

• conventional, template-directed genetic system. Thus, the first step is to establish a suitable metric for identifying and measuring their capacity for evolution. We propose that, for any given population of discrete living or proto-living units, the average fitness (wi) of the population will be evaluated as

• . Our aim is to design and fabricate a complete device containing a droplet generator, an incubation chamber, a droplet size sorter, a droplet fuser, and a droplet splitter; see Figure 7 for the device template. Microfluidic droplet generators will produce the droplet populations that will then be co

Chemical systems, chemical contiguity and the emergence of life

• Terrence P. Kee and
• Pierre-Alain Monnard

Beilstein J. Org. Chem. 2017, 13, 1551–1563, doi:10.3762/bjoc.13.155

• association with the interface of chemical systems. For instance, the activity of an RNA polymerase ribozyme was improved when the various RNA compounds of the system (the ribozyme, the template/primer) were derivatized with amphiphilic moieties and co-associated within micelle structures [69]. Although no

• protocellular „metabolism“. Inspired by the non-enzymatic, template-directed RNA polymerization in bulk aqueous solutions [7] (the synthesis of a RNA using a primer/template system and magnesium ions as catalysts), the Szostak group [21][82] has demonstrated that RNA could be synthesized within mixed vesicles

• composed of several types of “prebiotic” fatty acids and co-surfactants. That is, the vesicles could have retained the primer/template system while activated monomers crossed the vesicle bilayers by passive diffusion. Similarly, amino acids could be dimerized within vesicles [86]. In related experiments