Volatile emission and biosynthesis in endophytic fungi colonizing black poplar leaves

• Christin Walther,
• Pamela Baumann,
• Katrin Luck,
• Beate Rothe,
• Peter H. W. Biedermann,
• Jonathan Gershenzon,
• Tobias G. Köllner and
• Sybille B. Unsicker

Beilstein J. Org. Chem. 2021, 17, 1698–1711, doi:10.3762/bjoc.17.118

• , where only the sesquiterpene trichodiene was detected with FPP, while other substrates were not accepted [69]. In contrast, bi-functionality was also observed for the pinene and guaiene synthase from Daldinia eschscholzii EC12 and the pinene and guaiene synthase from Hypoxylon sp. EC28 (Figure 3) [45

Total synthesis of ent-pavettamine

• Memory Zimuwandeyi,
• Manuel A. Fernandes,
• Amanda L. Rousseau and
• Moira L. Bode

Beilstein J. Org. Chem. 2021, 17, 1440–1446, doi:10.3762/bjoc.17.99

• 17, followed by acetonide protection of the 1,3-diol functionality to yield the previously synthesized intermediate 4. The acetonide protecting group was chosen because of its stability under the future reaction conditions in addition to it being a convenient monitor of the relative configuration of

Antiviral therapy in shrimp through plant virus VLP containing VP28 dsRNA against WSSV

• Santiago Ramos-Carreño,
• Ivone Giffard-Mena,
• Jose N. Zamudio-Ocadiz,
• Alfredo Nuñez-Rivera,
• Ricardo Valencia-Yañez,
• Jaime Ruiz-Garcia,
• Maria Teresa Viana and
• Ruben D. Cadena-Nava

Beilstein J. Org. Chem. 2021, 17, 1360–1373, doi:10.3762/bjoc.17.95

• groups were challenged with WSSV by IM injection, with a dose of 10−6 Son2008 inoculum. (Herein “pellet feed” refers to when animals are fed with treatments, and “oral cavity” refers to when the VLPs treatment is given directly into the oral cavity through a needle to ensure intestinal functionality

• taken orally was more effective than when merely present in the feed as a coating. Taking the VLP-dsRNA28 orally assures capsid functionality by protecting the dsRNA structure. Administering VLP capsids inside the feed resulted in increased shrimp survival after challenged with the WSSV and treated per

Photoinduced post-modification of graphitic carbon nitride-embedded hydrogels: synthesis of 'hydrophobic hydrogels' and pore substructuring

• Cansu Esen and
• Baris Kumru

Beilstein J. Org. Chem. 2021, 17, 1323–1334, doi:10.3762/bjoc.17.92

• were characterized via FTIR analysis to elucidate structural footprints of CM embedding and vTA photographing. The broad peak in the range from 3639 cm−1 to 3136 cm−1 corresponds to the hydrogen bonding between carboxyl and hydroxy groups with amide functionality of the hydrogel backbone. Significant

• release which is highly beneficial for agricultural delivery systems. The grand outcome of embedded g-CN-based surface photomodification has significant advantages in terms of its non-toxic process and cost-efficient material resources. Pore substructuring In porous materials, the functionality of the

• pores is responsible for the main catalytic activity, such as in carbonaceous materials [47][48]. When a network with full functionality cannot be formed easily, one can form a rigid neutral host and modify the pores subsequently. Herein, the nanoporous system is magnified to macropores in hydrogel

A comprehensive review of flow chemistry techniques tailored to the flavours and fragrances industries

• Guido Gambacorta,
• James S. Sharley and
• Ian R. Baxendale

Beilstein J. Org. Chem. 2021, 17, 1181–1312, doi:10.3762/bjoc.17.90

• performance of these reaction types as a continuous-flow process is provided. Condensation reactions A carbonyl functionality is encountered in the vast majority of fragrance ingredients. The ability therefore to manipulate carbonyl moieties within a molecule will forever serve as an important transformation

Structural effects of meso-halogenation on porphyrins

• Keith J. Flanagan,
• Maximilian Paradiz Dominguez,
• Zoi Melissari,
• Hans-Georg Eckhardt,
• René M. Williams,
• Dáire Gibbons,
• Caroline Prior,
• Gemma M. Locke,
• Alina Meindl,
• Aoife A. Ryan and
• Mathias O. Senge

Beilstein J. Org. Chem. 2021, 17, 1149–1170, doi:10.3762/bjoc.17.88

• their relative versatility in areas such as directionality, the tunability of the σ-hole, hydrophobicity, and donor atom size [14]. These traits allow for the design of novel supramolecular architectures which are directive and reproducible, without relying on the hydrogen-bonding functionality which in

• have been omitted due to the alternate functionality muting any effect the halogen would have on the porphyrin molecule. The bond lengths, angles, and atom displacements are outlined in Supporting Information File 2, Table S7. In the structure of compound 20, while containing a halogen, it is apparent

N-tert-Butanesulfinyl imines in the asymmetric synthesis of nitrogen-containing heterocycles

• Joseane A. Mendes,
• Paulo R. R. Costa,
• Miguel Yus,
• Francisco Foubelo and
• Camilla D. Buarque

Beilstein J. Org. Chem. 2021, 17, 1096–1140, doi:10.3762/bjoc.17.86

Synthesis of 10-O-aryl-substituted berberine derivatives by Chan–Evans–Lam coupling and investigation of their DNA-binding properties

• Peter Jonas Wickhorst,
• Mathilda Blachnik,
• Denisa Lagumdzija and
• Heiko Ihmels

Beilstein J. Org. Chem. 2021, 17, 991–1000, doi:10.3762/bjoc.17.81

• functionality. Thus, this synthetic route represents the first successful Cu-mediated coupling reaction of berberine substrates. The DNA-binding properties of the 10-O-arylberberine derivatives with duplex and quadruplex DNA were studied by thermal DNA denaturation experiments, spectrometric titrations as well

• strands [30]. Due to their straightforward synthetic accessibility by substitution at the 9-hydroxy functionality of berberrubine (1b), 9-O-substituted berberine derivatives are particularly attractive. But so far, only functionalization at this position by alkylation [23][24][25][26] and nucleophilic

Beyond ribose and phosphate: Selected nucleic acid modifications for structure–function investigations and therapeutic applications

• Christopher Liczner,
• Kieran Duke,
• Gabrielle Juneau,
• Martin Egli and
• Christopher J. Wilds

Beilstein J. Org. Chem. 2021, 17, 908–931, doi:10.3762/bjoc.17.76

• oligonucleotides challenging. Thio-LNA (Figure 7F), which has sulfur incorporated at the C2' position, has similar binding properties as amino-LNA and β-ᴅ-LNA, but with varying biodistribution patterns and a higher cellular uptake in mice [145]. Work looking at carba-LNA, which lacks the O2' functionality, has

Enhanced target cell specificity and uptake of lipid nanoparticles using RNA aptamers and peptides

• Roslyn M. Ray,
• Anders Højgaard Hansen,
• Maria Taskova,
• Bernhard Jandl,
• Jonas Hansen,
• Citra Soemardy,
• Kevin V. Morris and
• Kira Astakhova

Beilstein J. Org. Chem. 2021, 17, 891–907, doi:10.3762/bjoc.17.75

• report the efficacy, delivery capability, and functionality of the addition of peptides and RNA aptamers in facilitating entry through a simplified BBB model as well as to determine whether inclusion of these molecules could facilitate cell specific uptake. We further show that LNPs generally exhibit a

Microwave-assisted multicomponent reactions in heterocyclic chemistry and mechanistic aspects

• Shivani Gulati,
• Stephy Elza John and
• Nagula Shankaraiah

Beilstein J. Org. Chem. 2021, 17, 819–865, doi:10.3762/bjoc.17.71

• condensation between ketone and formylquinoline. The amine and the intermediate A undergo Michael addition furnishing the keto-amine B. Further, an intramolecular cyclization with the attack of the amino group onto the carbonyl functionality with subsequent elimination of a water molecule results in the

Simulating the enzymes of ganglioside biosynthesis with Glycologue

• Andrew G. McDonald and
• Gavin P. Davey

Beilstein J. Org. Chem. 2021, 17, 739–748, doi:10.3762/bjoc.17.64

• describe an extension of this method to gangliosides, and to the enzyme reactions associated with their biosynthesis. The formalism and the associated web application, now renamed Glycologue, provide a way to explore the effects of mutations that result in a loss of functionality, or promotion of disease

Stereoselective syntheses of 3-aminocyclooctanetriols and halocyclooctanetriols

• Emine Salamci and
• Yunus Zozik

Beilstein J. Org. Chem. 2021, 17, 705–710, doi:10.3762/bjoc.17.59

• the small coupling constant (J = 2.2 Hz) the cis relation of the protons H-3 and H-2. Finally, the desired aminocyclooctanetriol 18 was obtained by hydrogenation of the azide functionality in compound 16 in 97% yield. In the second part of this work, we turned our attention to the stereospecific

• bromo groups, while the halogen functionality was introduced to the molecule by opening of the epoxide ring with HBr(g) or HCl(g) in MeOH. Structures of some important aminocyclitols. Synthesis of cyclic sulfate 9. Synthesis of aminocyclooctanetriol 12. Synthesis of aminocyclooctanetriol 18. Synthesis

α,γ-Dioxygenated amides via tandem Brook rearrangement/radical oxygenation reactions and their application to syntheses of γ-lactams

• Mikhail K. Klychnikov,
• Radek Pohl,
• Ivana Císařová and
• Ullrich Jahn

Beilstein J. Org. Chem. 2021, 17, 688–704, doi:10.3762/bjoc.17.58

• Derivatizations of lactams 12 lead to valuable compound classes for further elaboration. The alkoxyamine functionality of lactam trans-12b was reductively cleaved by excess zinc in the presence of acetic acid at elevated temperature (Scheme 6); the dihydroxy lactam 14 was obtained in 82% yield. In the presence of

Effective microwave-assisted approach to 1,2,3-triazolobenzodiazepinones via tandem Ugi reaction/catalyst-free intramolecular azide–alkyne cycloaddition

• Maryna O. Mazur,
• Oleksii S. Zhelavskyi,
• Eugene M. Zviagin,
• Svitlana V. Shishkina,
• Vladimir I. Musatov,
• Maksim A. Kolosov,
• Elena H. Shvets,
• Anna Yu. Andryushchenko and
• Valentyn A. Chebanov

Beilstein J. Org. Chem. 2021, 17, 678–687, doi:10.3762/bjoc.17.57

• products from substrates with preinstalled functionality for IAAC (azide and alkyne groups) and then optimizing the conditions for the azide–alkyne cycloaddition that should lead to the desired compounds. The key precursor in our study bearing an azide functional group is 2-azidobenzaldehyde 2, which can

Designed whole-cell-catalysis-assisted synthesis of 9,11-secosterols

• Marek Kõllo,
• Marje Kasari,
• Villu Kasari,
• Tõnis Pehk,
• Ivar Järving,
• Margus Lopp,
• Arvi Jõers and
• Tõnis Kanger

Beilstein J. Org. Chem. 2021, 17, 581–588, doi:10.3762/bjoc.17.52

• transformation. Also, the substituent at C17 does not affect the KSH performance: steroids with C17 keto functionality (i.e., 2 and 3) or cholesterol-like side chains at C20 (i.e., 1) were all transformed efficiently to the corresponding 9,11-dihydroxylated products. 1H and 13C 1D and 2D (COSY, HSQ and HMBC) NMR

Synthesis of N-perfluoroalkyl-3,4-disubstituted pyrroles by rhodium-catalyzed transannulation of N-fluoroalkyl-1,2,3-triazoles with terminal alkynes

• Olga Bakhanovich,
• Viktor Khutorianskyi,
• Vladimir Motornov and
• Petr Beier

Beilstein J. Org. Chem. 2021, 17, 504–510, doi:10.3762/bjoc.17.44

• transannulation/carboxylation process was demonstrated for the construction of the functionalized pyrrole 2-carboxylic acid with an N-trifluoromethyl functionality. Thus, this work improves the synthetic access to N-perfluoroalkyl-3,4-disubstituted pyrroles. Selected pyrrole-containing natural products, drugs

Synthesis of legonmycins A and B, C(7a)-hydroxylated bacterial pyrrolizidines

• Wilfred J. M. Lewis,
• David M. Shaw and
• Jeremy Robertson

Beilstein J. Org. Chem. 2021, 17, 334–342, doi:10.3762/bjoc.17.31

• , was also reported in 1980 [10]. Following a 23-year hiatus, two papers submitted within two weeks of each other reported, respectively: (1) the isolation from Streptomyces sp. UMA-044 and characterization of NP25302, that differs from bohemamine in lacking the 6,7-epoxide functionality [11] and (2

• -ketoester 13. The appended ester functionality in 14 has, at some point, to be removed, as its presence complicates a potential application to the (2-methyl-substituted) legonmycins, and it exerts a potentially stabilizing electronic effect on pyrrolic intermediates that could be unhelpful in downstream

Supramolecular polymerization of sulfated dendritic peptide amphiphiles into multivalent L-selectin binders

• David Straßburger,
• Svenja Herziger,
• Katharina Huth,
• Moritz Urschbach,
• Rainer Haag and
• Pol Besenius

Beilstein J. Org. Chem. 2021, 17, 97–104, doi:10.3762/bjoc.17.10

• [6][7][8][9] are only few of the numerous examples for multivalent protein–protein or protein–carbohydrate interactions that underline their pivotal role in biology. Mimicking polyvalency using synthetic systems has therefore become a growing field and the high degree of functionality renders

• purified by RP-HPLC and separated from impurities, like disubstituted byproduct, to finally afford 5 in 68% yield. Subsequently, an azide functionality was easily introduced using azidoacetic acid NHS ester to obtain compound 6. In the next step, the solubilizing side-arm 4 was attached twice to the

Progress in the total synthesis of inthomycins

• Bidyut Kumar Senapati

Beilstein J. Org. Chem. 2021, 17, 58–82, doi:10.3762/bjoc.17.7

• -interrupted oxazolyltriene unit is conjugated to a chiral β-hydroxycarbonyl center of an amide functionality. Inthomycin A ((+)-1), the first member of the inthomycin family, was isolated by Omura’s group from the strain of Streptomyces sp. OM-5714 in 1990 [1]. Then, the following year, Henkel and Zeek had

Molecular basis for protein–protein interactions

• Brandon Charles Seychell and
• Tobias Beck

Beilstein J. Org. Chem. 2021, 17, 1–10, doi:10.3762/bjoc.17.1

• interactions; Introduction From signalling over transport to catalysis, the broad functionality of proteins is essential in the cellular machinery. To this effect, proteins can be seen as the workforce of the cell. Proteins relay some of their functionality via interactions between protein nodes called

• functionality and the corresponding pathways. Important roles of PPIs include hormone reception [2], protease inhibition [3], antibody–antigen complexes [4], gene regulation [5], and large biomolecular assemblies [6]. PPI identification and prediction are important for targeting anticancer strategies [7

Synthesis of imidazo[1,5-a]pyridines via cyclocondensation of 2-(aminomethyl)pyridines with electrophilically activated nitroalkanes

• Dmitrii A. Aksenov,
• Nikolai A. Arutiunov,
• Vladimir V. Maliuga,
• Alexander V. Aksenov and
• Michael Rubin

Beilstein J. Org. Chem. 2020, 16, 2903–2910, doi:10.3762/bjoc.16.239

• superior electrophile in comparison to the ester function. Indeed, this bielectrophilic reagent reacted only at the nitro group, providing the amide 20 as the sole product. The yield was quite marginal, primarily due to decomposition of the fragile ester functionality under the harsh reaction conditions

Incorporation of a metal-mediated base pair into an ATP aptamer – using silver(I) ions to modulate aptamer function

• Marius H. Heddinga and
• Jens Müller

Beilstein J. Org. Chem. 2020, 16, 2870–2879, doi:10.3762/bjoc.16.236

• replaced by coordinate bonds to one (or more) transition metal ions [13][14]. They are compatible with normal DNA duplex structures [15][16] and can be used to introduce a metal-based functionality into DNA [17][18]. Importantly, metal-mediated base-pair formation has been successfully applied in metal

• investigate the envisaged functionality of the modified structure-switching signaling aptamers (f = fluorescein, q = DABCYL). The strand shown in black is derived from the ATP/AMP-binding aptamer. System A: the aptamers 1af, 1bf, 1cf, and 1df with the complementary sequence 1q (X = imidazole, f = fluorescein

Changed reactivity of secondary hydroxy groups in C8-modified adenosine – lessons learned from silylation

• Jennifer Frommer and
• Sabine Müller

Beilstein J. Org. Chem. 2020, 16, 2854–2861, doi:10.3762/bjoc.16.234

• , assays that implement separation steps require RNA molecules conjugated to an affinity tag such as biotin, or any other functionality for functional selection [11][12]. Very importantly, terminal modification/functionalization is not always suitable to a specific aim. Thus, in addition to building blocks

• for 5’- or 3’-terminal attachment of a desired functionality, nucleoside derivatives that, upon site-specific incorporation at a pre-determined position of RNA, can be used for post-synthetic conjugation, are required. A number of chemistries are available to specifically attach a molecular entity to

• , molecular entities to RNA molecules may disturb functionality, and thus requires careful definition of the conjugation site. As mentioned above, in addition to 5’- and 3’-terminal conjugation, often internal modification of RNA molecules is required. Thus, in order to avoid changes to the RNA sequence

Synthesis and investigation of quadruplex-DNA-binding, 9-O-substituted berberine derivatives

• Jonas Becher,
• Daria V. Berdnikova,
• Heiko Ihmels and
• Christopher Stremmel

Beilstein J. Org. Chem. 2020, 16, 2795–2806, doi:10.3762/bjoc.16.230

• terminated with an N-benzylamide functionality to establish the attractive hydrogen bonding and π stacking with the thymidine residues in the loops in G4-DNA, so that this ligand binds with very high selectivity to the particular quadruplex-forming oligonucleotide J19 [49]. Overall, the above-mentioned