Secondary metabolites of Bacillus subtilis impact the assembly of soil-derived semisynthetic bacterial communities

• Heiko T. Kiesewalter,
• Carlos N. Lozano-Andrade,
• Mikael L. Strube and
• Ákos T. Kovács

Beilstein J. Org. Chem. 2020, 16, 2983–2998, doi:10.3762/bjoc.16.248

• synthesised by NRPS gene clusters (surfactin, plipastatin, and bacillibactin) and one by a hybrid NRPS–PKS gene cluster (bacillaene, Figure 1). The well-studied biosurfactant surfactin, encoded by the srfAA-AD gene cluster, reduces the surface tension needed for swarming and sliding motility [38][39]. The

• incubated at 30 °C with continuous shaking (548 cpm, 2 mm), and the OD600 was measured in 15 min intervals over 24 h. All graphical visualisations were prepared using ggplot2 [79]. Overview of the NRPs surfactin, plipastatin, bacillibactin, and iturin as well as the hybrid NRP-PK bacillaene produced by

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

• temperature than the other ones. Most notably, the representative DNA denaturation analysis with ligand 4e and different quadruplex forms clearly reveals a significant selectivity. Hence, the hybrid antiparallel G4-DNA 22AG as well as the parallel quadruplex-forming KRAS sequence are stabilized to a

Ring-closing metathesis of prochiral oxaenediynes to racemic 4-alkenyl-2-alkynyl-3,6-dihydro-2H-pyrans

• Viola Kolaříková,
• Markéta Rybáčková,
• Martin Svoboda and
• Jaroslav Kvíčala

Beilstein J. Org. Chem. 2020, 16, 2757–2768, doi:10.3762/bjoc.16.226

• internal standards. Chemical shifts are given in parts per million and coupling constants in hertz. Mass spectra (ESI, APCI) and HRMS spectra were measured with a hybrid LTQ Obitrap XL instrument (Thermo Fisher Scientific). All reactions were performed in a dry inert atmosphere (Ar) in oven-dried flasks

Encrypting messages with artificial bacterial receptors

• Pragati Kishore Prasad,
• Naama Lahav-Mankovski,
• Leila Motiei and
• David Margulies

Beilstein J. Org. Chem. 2020, 16, 2749–2756, doi:10.3762/bjoc.16.225

• during bacterial growth. The emission spectra of the bacterial samples labeled with the three DNA-based receptors were recorded using black flat-bottom 384-well microplates (Corning) and a BioTek synergy H4 hybrid multiwell plate reader. The fluorescence responses were measured using excitation

Leveraging glycomics data in glycoprotein 3D structure validation with Privateer

• Haroldas Bagdonas,
• Daniel Ungar and
• Jon Agirre

Beilstein J. Org. Chem. 2020, 16, 2523–2533, doi:10.3762/bjoc.16.204

• containing glycans that were previously unreported and inconsistent with glycan biosynthetic pathways. In particular, the model contained oligosaccharide chains with Man-(1→3)-GlcNAc and GlcNAc-(1→3)-GlcNAc linkages, β-galactosyl motifs capping oligomannose-type glycans and hybrid-type glycans containing

Palladium nanoparticles supported on chitin-based nanomaterials as heterogeneous catalysts for the Heck coupling reaction

• Tony Jin,
• Malickah Hicks,
• Davis Kurdyla,
• Sabahudin Hrapovic,
• Edmond Lam and
• Audrey Moores

Beilstein J. Org. Chem. 2020, 16, 2477–2483, doi:10.3762/bjoc.16.201

• parameters were performed on PdCl2 and either ChNC or ChsNC, but with no H2 reductant. In this case, the solution color remained yellow, indicating that using either ChNC or ChsNC alone cannot fully reduce PdCl2. The resulting hybrid materials are noted PdNP@ChNC and PdNP@ChsNC, respectively. Dihydrogen was

Catalytic trifluoromethylation of iodoarenes by use of 2-trifluoromethylated benzimidazoline as trifluoromethylating reagent

• Tatsuhiro Uchikura,
• Nanami Kamiyama,
• Taisuke Ishikawa and
• Takahiko Akiyama

Beilstein J. Org. Chem. 2020, 16, 2442–2447, doi:10.3762/bjoc.16.198

• diamine ligandsa. Supporting Information Supporting Information File 480: Details of screening experiments, synthetic procedures and characterization data of new compounds, and copies of spectra. Funding JSPS KAKENHI Grant Numbers JP17H03060, JP20H00380, and JP20H04826 (Hybrid Catalysis)

Recent developments in enantioselective photocatalysis

• Callum Prentice,
• James Morrisson,
• Andrew D. Smith and
• Eli Zysman-Colman

Beilstein J. Org. Chem. 2020, 16, 2363–2441, doi:10.3762/bjoc.16.197

How and why plants and human N-glycans are different: Insight from molecular dynamics into the “glycoblocks” architecture of complex carbohydrates

• Carl A. Fogarty,
• Aoife M. Harbison,
• Amy R. Dugdale and
• Elisa Fadda

Beilstein J. Org. Chem. 2020, 16, 2046–2056, doi:10.3762/bjoc.16.171

• ][21][22][23]. More specifically, we investigate how core α(1-3)-linked fucose (Fuc) and β(1-2)-linked xylose (Xyl) affect the structure and dynamics of plants N-glycoforms [23] and of hybrid constructs with mammalian N-glycoforms [24]. At first glance plants protein N-glycosylation [23] is quite

• refer to N-glycans as either “plant” or “hybrid” separately. Nevertheless, it is important to underline that some of these motifs, such as β(1-2) xylosylation and difucosylated core are also found in invertebrate N- glycosylation [30]. Finally, we discuss these findings within a framework where the

• position of the deoxy-C6 of the fucose in LeX relative to LeA. Hybrid N-glycans. To understand how characteristic plant N-glycan motifs can affect the structure of mammalian N-glycoforms, we have designed and analysed the dynamics of a set of hybrid systems. In particular, we were interested in the effect

Synthesis, docking study and biological evaluation of ᴅ-fructofuranosyl and ᴅ-tagatofuranosyl sulfones as potential inhibitors of the mycobacterial galactan synthesis targeting the galactofuranosyltransferase GlfT2

• Marek Baráth,
• Jana Jakubčinová,
• Zuzana Konyariková,
• Stanislav Kozmon,
• Katarína Mikušová and
• Maroš Bella

Beilstein J. Org. Chem. 2020, 16, 1853–1862, doi:10.3762/bjoc.16.152

• mechanism studies using computational chemistry methods. The probable reaction mechanisms were studied by hybrid DFT QM/MM molecular dynamics simulations [11] where the possible transition state (TS) structures were localized. The observation of the possible TS structure opens the opportunities for the in

Et₃N/DMSO-supported one-pot synthesis of highly fluorescent β-carboline-linked benzothiophenones via sulfur insertion and estimation of the photophysical properties

• Dharmender Singh,
• Vipin Kumar and
• Virender Singh

Beilstein J. Org. Chem. 2020, 16, 1740–1753, doi:10.3762/bjoc.16.146

• hybrid containing the benzothiophene moiety (Figure 1) [57][58]. The present study was inspired by the recent findings of Nguyen and co-workers [59][60][61]. As a part of our ongoing project [62][63], we devised a simple and efficient one-pot practical approach for the construction of β-carboline

Microwave-assisted efficient one-pot synthesis of N²-(tetrazol-5-yl)-6-aryl/heteroaryl-5,6-dihydro-1,3,5-triazine-2,4-diamines

• Moustafa Sherief Moustafa,
• Ramadan Ahmed Mekheimer,
• Saleh Mohammed Al-Mousawi,
• Mohamed Abd-Elmonem,
• Hesham El-Zorba,
• Afaf Mohamed Abdel Hameed,
• Tahany Mahmoud Mohamed and
• Kamal Usef Sadek

Beilstein J. Org. Chem. 2020, 16, 1706–1712, doi:10.3762/bjoc.16.142

• specific biological target such as a receptor or an enzyme. A promising strategy that overcomes the classical one-target, one-molecule approach is the design of stable chemical hybrid molecules which are a combination of two biologically active scaffolds acting at different targets [20][21][22][23][24

NHC-catalyzed enantioselective synthesis of β-trifluoromethyl-β-hydroxyamides

• Alyn T. Davies,
• Mark D. Greenhalgh,
• Alexandra M. Z. Slawin and
• Andrew D. Smith

Beilstein J. Org. Chem. 2020, 16, 1572–1578, doi:10.3762/bjoc.16.129

• stereogenic trifluoromethyl centers is through enantioselective addition of enolates or their equivalents to prochiral trifluoromethyl ketones (Figure 1A). Within this area, a common catalytic approach has utilized aliphatic ketones as enolate equivalents using prolinamide, cinchona, or hybrid catalysts that

Five-component, one-pot synthesis of an electroactive rotaxane comprising a bisferrocene macrocycle

• Natalie Lagesse,
• Luca Pisciottani,
• Maxime Douarre,
• Pascale Godard,
• Brice Kauffmann,
• Vicente Martí-Centelles and
• Nathan D. McClenaghan

Beilstein J. Org. Chem. 2020, 16, 1564–1571, doi:10.3762/bjoc.16.128

• Rigaku FRX® high flux rotating anode with a Pilatus 200K hybrid pixel detector. Using Olex2 [27], the structure was solved with the ShelXT [28] structure solution program using Intrinsic Phasing and refined with the ShelXL [29] refinement package using the full least-squares correlation matrix. The non

Heterogeneous photocatalysis in flow chemical reactors

• Christopher G. Thomson,
• Ai-Lan Lee and
• Filipe Vilela

Beilstein J. Org. Chem. 2020, 16, 1495–1549, doi:10.3762/bjoc.16.125

• conjugated porous polymers (CPPs) [3][10][171], covalent organic frameworks (COFs) [172][173][174][175], and hybrid materials, such as metal–organic frameworks (MOFs) [1][176][177]. MOFs, for example, have three distinct origins of photocatalysis; (i) semiconducting metal cluster nodes, (ii) photocatalytic

In silico rationalisation of selectivity and reactivity in Pd-catalysed C–H activation reactions

• Liwei Cao,
• Mikhail Kabeshov,
• Steven V. Ley and
• Alexei A. Lapkin

Beilstein J. Org. Chem. 2020, 16, 1465–1475, doi:10.3762/bjoc.16.122

• modern supercomputer clusters [19]. The structures were generated by the Python module developed in house and explained in detail elsewhere [20]. Electronic energies were evaluated using Becke’s three-parameter hybrid B3LYP functional, while the molecular orbitals are expanded in triple-zeta all electron

Synthesis and properties of quinazoline-based versatile exciplex-forming compounds

• Rasa Keruckiene,
• Simona Vekteryte,
• Ervinas Urbonas,
• Matas Guzauskas,
• Eigirdas Skuodis,
• Dmytro Volyniuk and
• Juozas V. Grazulevicius

Beilstein J. Org. Chem. 2020, 16, 1142–1153, doi:10.3762/bjoc.16.101

• . The potentials were calibrated against the standard ferrocene/ferrocenium (Fc/Fc+) redox system [24]. The ground-state geometries were optimized by using the B3LYP (Becke three parameters hybrid functional with Lee–Yang–Perdew correlation) [25] functional at the 6-31G (d, p) level of theory in vacuum

Fabclavine diversity in Xenorhabdus bacteria

• Sebastian L. Wenski,
• Harun Cimen,
• Natalie Berghaus,
• Sebastian W. Fuchs,
• Selcuk Hazir and
• Helge B. Bode

Beilstein J. Org. Chem. 2020, 16, 956–965, doi:10.3762/bjoc.16.84

• for bioactive compounds are required, such as the bacterial genera Xenorhabdus or Photorhabdus. In these strains, fabclavines are widely distributed SMs with a broad-spectrum bioactivity. Fabclavines are hybrid SMs derived from nonribosomal peptide synthetases (NRPS), polyunsaturated fatty acid (PUFA

• of fabclavines as major antibiotics in several entomopathogenic strains, our work lays the foundation for the rapid fabclavine identification and dereplication as the basis for future work of this widespread and bioactive SM class. Keywords: antibiotic; fabclavine; NRPS-PKS hybrid; secondary

• originally also contained the NRPS-PKS-hybrid genes (Figure 2) [22]. In contrast, the BGC of P. temperata is reduced to only harbor the homologous genes of fclC, fclD and fclE (Figure 2) [22]. X. innexi also harbors a fcl-like BGC, with protein identities of 68–90% compared to X. stockiae (Figure S1

Diversity-oriented synthesis of 17-spirosteroids

• Benjamin Laroche,
• Thomas Bouvarel,
• Martin Louis-Sylvestre and
• Bastien Nay

Beilstein J. Org. Chem. 2020, 16, 880–887, doi:10.3762/bjoc.16.79

• transcription, or directly bind nuclear receptors [59][60][61]. In principle, steroids could thus be used as cargo molecules to deliver new chemical entities inside the nucleus, highlighting the potential of hybrid steroid molecules [62]. For example, De Riccardis designed steroid scaffolds directly fused to a

Copper catalysis with redox-active ligands

• Agnideep Das,
• Yufeng Ren,
• Cheriehan Hessin and
• Marine Desage-El Murr

Beilstein J. Org. Chem. 2020, 16, 858–870, doi:10.3762/bjoc.16.77

• another family of galactose oxidase mimics based on copper(II) complex 4 bearing a non-innocent iminophenol-iminopyridine hybrid ligand 3 that performed two-electron oxidations of primary alcohols to aldehydes (Scheme 2) [15]. Catalyst 4 was fully characterized by combined EPR, cyclic voltammetry and

A systematic review on silica-, carbon-, and magnetic materials-supported copper species as efficient heterogeneous nanocatalysts in “click” reactions

• Pezhman Shiri and
• Jasem Aboonajmi

Beilstein J. Org. Chem. 2020, 16, 551–586, doi:10.3762/bjoc.16.52

• . Subsequently, a range of hybrid molecules, including triazole–benzimidazoles 50–53, triazole–benzothiazole 54, and triazole–benzoxazole 55, was prepared under the above-mentioned conditions (Scheme 8). The benefits of this catalytic system were mild reaction conditions, low catalyst loadings, a diverse set of

Synthesis of triphenylene-fused phosphole oxides via C–H functionalizations

• Md. Shafiqur Rahman and
• Naohiko Yoshikai

Beilstein J. Org. Chem. 2020, 16, 524–529, doi:10.3762/bjoc.16.48

• phosphole oxides, which are distinct from Saito’s compounds [15] as well as from other reported examples [26][27][28] in terms of the mode of fusion of the phosphole and triphenylene units. The present phosphole/triphenylene hybrid molecules displayed absorption and emission profiles that reflected the

Six-fold C–H borylation of hexa-peri-hexabenzocoronene

• Mai Nagase,
• Kenta Kato,
• Akiko Yagi,
• Yasutomo Segawa and
• Kenichiro Itami

Beilstein J. Org. Chem. 2020, 16, 391–397, doi:10.3762/bjoc.16.37

• rotating anode (Graphite-monochromated Mo Kα radiation (λ = 0.71073 Å)) and PILATUS200K hybrid photon-counting detector. Cell parameters were determined and refined, and raw frame data were integrated using CrysAlisPro (Agilent Technologies, 2010). The structures were solved by direct methods with (SHELXT

Room-temperature Pd/Ag direct arylation enabled by a radical pathway

• Amy L. Mayhugh and
• Christine K. Luscombe

Beilstein J. Org. Chem. 2020, 16, 384–390, doi:10.3762/bjoc.16.36

• mechanism has been recently supported by 13C and 2H KIE experiments for the arylation of benzo[b]thiophene, although at C3 [13]. In contrast to these pathways, the radical trap and dark experiments reported above indicate a hybrid Pd(I) radical species induced by visible light is involved in the catalytic

• to form hybrid palladium-radical intermediate 5. This carbon-centered radical can then add to the indole. From here, three different pathways to rearomatize 7 are possible, eventually affording the arylated product 10. Pd(0) can be regenerated by a base; in this case, the silver carboxylate. This

Architecture and synthesis of P,N-heterocyclic phosphine ligands

• Wisdom A. Munzeiwa,
• Bernard Omondi and
• Vincent O. Nyamori

Beilstein J. Org. Chem. 2020, 16, 362–383, doi:10.3762/bjoc.16.35

• steps, the lithiation and the introduction of the phosphine were performed at low temperature (−70 °C), compound 81 was obtained in 63% yield [80]. In both instances, the other isomer was present in minute quantities and could be separated by recrystallization. Hybrid phosphine N-heterocyclic carbenes

• , which can present possibilities for other interesting applications not only limited to organometallic catalysis. The combination of different heterocycles to make hybrid ligands can stimulate studies on their applicability in medicinal and OLEDs among other applications. In short, this review article