Chemical and biosynthetic potential of Penicillium shentong XL-F41

• Ran Zou,
• Xin Li,
• Xiaochen Chen,
• Yue-Wei Guo and
• Baofu Xu

Beilstein J. Org. Chem. 2024, 20, 597–606, doi:10.3762/bjoc.20.52

• investigations, accompanied by fermentation media optimization, of a newly isolated fungus, Penicillium shentong XL-F41, led to the isolation of twelve compounds. Among these are two novel indole terpene alkaloids, shentonins A and B (1 and 2), and a new fatty acid 3. Shentonin A (1) is distinguished by an

A myo-inositol dehydrogenase involved in aminocyclitol biosynthesis of hygromycin A

• Michael O. Akintubosun and
• Melanie A. Higgins

Beilstein J. Org. Chem. 2024, 20, 589–596, doi:10.3762/bjoc.20.51

• ). bsIDH (Uniprot ID P26935) was gene synthesized with codon optimization and cloned into pET28a by Twist Bioscience. pET28a-bsIDH was transformed into E. coli BL21 star (DE3) (Agilent). For overnight cultures, 5–6 colonies were inoculated into 50 mL of LB supplemented with 10 μg mL−1 ampicillin and 1.5 μg

Recent developments in the engineered biosynthesis of fungal meroterpenoids

• Zhiyang Quan and
• Takayoshi Awakawa

Beilstein J. Org. Chem. 2024, 20, 578–588, doi:10.3762/bjoc.20.50

• the filamentous fungus Stachbotrys bisbyi were produced in A. oryzae to synthesize grifolic acid (60) (Figure 9) [39]. In addition, the gene encoding DCAS, a prenyl group oxidase from the plant Rhododendron dauricum, was additionally expressed in A. oryzae expressing stbAC after codon-optimization to

Possible bi-stable structures of pyrenebutanoic acid-linked protein molecules adsorbed on graphene: theoretical study

• Yasuhiro Oishi,
• Motoharu Kitatani and
• Koichi Kusakabe

Beilstein J. Org. Chem. 2024, 20, 570–577, doi:10.3762/bjoc.20.49

• previous paper [9]. After the structural optimization calculation of the (meta)stable conformations until the Hellman–Feynman force acting on each atom was less than 10−6 Ry/Bohr, the nudged elastic band method determined the minimum energy pathway. Intermediate images created by linear interpolation

Synthesis and biological profile of 2,3-dihydro[1,3]thiazolo[4,5-b]pyridines, a novel class of acyl-ACP thioesterase inhibitors

• Jens Frackenpohl,
• David M. Barber,
• Guido Bojack,
• Birgit Bollenbach-Wahl,
• Ralf Braun,
• Rahel Getachew,
• Sabine Hohmann,
• Kwang-Yoon Ko,
• Karoline Kurowski,
• Bernd Laber,
• Rebecca L. Mattison,
• Thomas Müller,
• Anna M. Reingruber,
• Dirk Schmutzler and
• Andrea Svejda

Beilstein J. Org. Chem. 2024, 20, 540–551, doi:10.3762/bjoc.20.46

• via reduction of the thiazole moiety: optimization of the reaction conditions.a Preemergence in vivo efficacy screening of 2,3-dihydro[1,3]thiazolo[4,5-b]pyridines 7a–c and 13a–c as well as of N-acylated analogs 14a–c and 16a–f against selected monocotyledon weeds, and binding affinity to FAT A from

Ligand effects, solvent cooperation, and large kinetic solvent deuterium isotope effects in gold(I)-catalyzed intramolecular alkene hydroamination

• Ruichen Lan,
• Brock Yager,
• Yoonsun Jee,
• Cynthia S. Day and
• Amanda C. Jones

Beilstein J. Org. Chem. 2024, 20, 479–496, doi:10.3762/bjoc.20.43

• gold and HOTf, however, they are not easily explained by simple either/or mechanisms [14][32][33]. Due in part to optimization challenges and in part to remaining gaps in characterizing structure–activity relationships for alkene hydroamination, we sought to obtain additional understanding by

• characterized as general acid catalysis (without invoking gold alkyl intermediates). Although many facets of this reaction remain to be understood, there are many practical implications of our work. For example, future catalyst optimization should focus on designing ligands that create more electrophilc gold

Synthesis of 2,2-difluoro-1,3-diketone and 2,2-difluoro-1,3-ketoester derivatives using fluorine gas

• Alexander S. Hampton,
• David R. W. Hodgson,
• Graham McDougald,
• Linhua Wang and
• Graham Sandford

Beilstein J. Org. Chem. 2024, 20, 460–469, doi:10.3762/bjoc.20.41

• selective difluorination using fluorine gas. After screening basic additives as mediating agents and subsequent optimization (see Supporting Information File 1), we found that reaction of ethyl benzoylacetate (4a), quinuclidine (1.5 equiv), and fluorine (3 equiv) in acetonitrile gave the desired

Green and sustainable approaches for the Friedel–Crafts reaction between aldehydes and indoles

• Periklis X. Kolagkis,
• Eirini M. Galathri and
• Christoforos G. Kokotos

Beilstein J. Org. Chem. 2024, 20, 379–426, doi:10.3762/bjoc.20.36

• advantages. DBDMH is a well-known brominating and oxidizing agent that has recently gained special attention as a highly efficient, commercially available and inexpensive homogeneous catalyst [81]. After optimization, it was found that when employing a molar ratio of benzaldehyde, indole and DBDMH of 1:2

Facile approach to N,O,S-heteropentacycles via condensation of sterically crowded 3H-phenoxazin-3-one with ortho-substituted anilines

• Eugeny Ivakhnenko,
• Vasily Malay,
• Pavel Knyazev,
• Nikita Merezhko,
• Nadezhda Makarova,
• Oleg Demidov,
• Gennady Borodkin,
• Andrey Starikov and
• Vladimir Minkin

Beilstein J. Org. Chem. 2024, 20, 336–345, doi:10.3762/bjoc.20.34

• ). The DFT calculations [32] were performed using the Gaussian 16 program package [33] with the B3LYP functional [34] and the 6-311++G(d,p) basis set. The structures corresponding to minima on the potential energy surface and states with broken symmetry [20] were found through complete optimization of

Unveiling the regioselectivity of rhodium(I)-catalyzed [2 + 2 + 2] cycloaddition reactions for open-cage C₇₀ production

• Cristina Castanyer,
• Anna Pla-Quintana,
• Anna Roglans,
• Albert Artigas and
• Miquel Solà

Beilstein J. Org. Chem. 2024, 20, 272–279, doi:10.3762/bjoc.20.28

• was obtained from HRMS, which gave a single peak at m/z 1138.0868 corresponding to [2a + Na]+. Further optimization was then carried out to obtain the bis(fulleroid) derivative alone (Table S1 in Supporting Information File 1). On increasing the reaction temperature to 120 °C and 180 °C the results

Nucleophilic functionalization of thianthrenium salts under basic conditions

• Xinting Fan,
• Duo Zhang,
• Xiangchuan Xiu,
• Bin Xu,
• Yu Yuan,
• Feng Chen and
• Pan Gao

Beilstein J. Org. Chem. 2024, 20, 257–263, doi:10.3762/bjoc.20.26

• atmosphere. Isolated yields. Substrate scope of amines. Reaction conditions: alkylthianthrenium salts 1 (0.3 mmol), amines 2 (0.2 mmol), DIPEA (0.4 mmol) in 2.0 mL of MeCN at 80 °C for 16 h under air atmosphere. Isolated yields. Scale-up reaction. Optimization of the thioetherification of S-(alkyl

Optimizations of lipid II synthesis: an essential glycolipid precursor in bacterial cell wall synthesis and a validated antibiotic target

• Milandip Karak,
• Cian R. Cloonan,
• Brad R. Baker,
• Rachel V. K. Cochrane and
• Stephen A. Cochrane

Beilstein J. Org. Chem. 2024, 20, 220–227, doi:10.3762/bjoc.20.22

• have successfully optimized a modular approach for the synthesis of lipid II and its analogues, including variants with distinct prenyl-chain lengths. The key to this methodology lies in the optimization of glycosylation conditions, utilizing readily available glycosyl donors, which is a pivotal step

• lipid II-binding antimicrobials, see recent review by Buijs and co-workers [2]. List of i) glycosyl donors and ii) glycosyl acceptors used in this study. Synthesis of disaccharide pentapeptide core 7. Synthesis of lipid II (11) and its analogues 8–10. Optimization of the glycosylation conditions.a

Copper-catalyzed multicomponent reaction of β-trifluoromethyl β-diazo esters enabling the synthesis of β-trifluoromethyl N,N-diacyl-β-amino esters

• Youlong Du,
• Haibo Mei,
• Ata Makarem,
• Ramin Javahershenas,
• Vadim A. Soloshonok and
• Jianlin Han

Beilstein J. Org. Chem. 2024, 20, 212–219, doi:10.3762/bjoc.20.21

• bring any improvement on the reaction outcome (Table 1, entries 6 and 7). Further optimization of the reaction conditions focused on the variation of the amounts of amine 1a and tert-butyl nitrite (Table 1, entries 8–12). Considering the instability of the diazo structure generated from amine 1a, we

• . Control experiments. Proposed reaction mechanism. Scale-up synthesis. Optimization of reaction conditions.a Supporting Information Supporting Information File 8: Experimental details and spectral data. Funding We gratefully acknowledge the financial support from the National Natural Science Foundation

Chiral phosphoric acid-catalyzed transfer hydrogenation of 3,3-difluoro-3H-indoles

• Yumei Wang,
• Guangzhu Wang,
• Yanping Zhu and
• Kaiwu Dong

Beilstein J. Org. Chem. 2024, 20, 205–211, doi:10.3762/bjoc.20.20

• . Reaction optimization studies.a The effect of Hantzsch esters and other reaction parameters.a Supporting Information Supporting Information File 4: Full experimental details and characterization data of all compounds. Funding We are grateful for the financial support provided by the National Nature

Metal-catalyzed coupling/carbonylative cyclizations for accessing dibenzodiazepinones: an expedient route to clozapine and other drugs

• Amina Moutayakine and
• Anthony J. Burke

Beilstein J. Org. Chem. 2024, 20, 193–204, doi:10.3762/bjoc.20.19

• )aminoaniline.a Optimization of the Chan–Lam coupling conditions between o-phenylenediamine (1a) and 2-bromophenylboronic acid (7).a Substrate scope of the one-pot synthesis of dibenzodiazepine using via Chan–Lam coupling/carbonylative intramolecular cyclization.a Supporting Information Supporting Information

Tandem Hock and Friedel–Crafts reactions allowing an expedient synthesis of a cyclolignan-type scaffold

• Viktoria A. Ikonnikova,
• Cristina Cheibas,
• Oscar Gayraud,
• Alexandra E. Bosnidou,
• Nicolas Casaretto,
• Gilles Frison and
• Bastien Nay

Beilstein J. Org. Chem. 2024, 20, 162–169, doi:10.3762/bjoc.20.15

• , in the sole presence of MgSO4, no reaction was observed (Table 1, entry 6). Furthermore, Yb(OTf)3 or ZnCl2 mainly resulted in aldehyde 3 (Table 1, entries 7 and 8), while AlCl3 performed well with an 83% yield of 4 (Table 1, entry 9). This optimization validated the expected tandem sequence of

• and aromatic nucleophiles in the one-pot transformation. aNot determined (mixture with unidentified products). Reaction optimization toward 4 (see also Scheme 2). Supporting Information Crystallographic data of compound 6 were deposited in the Cambridge Crystallographic Data Center under the CCDC

Copper-promoted C5-selective bromination of 8-aminoquinoline amides with alkyl bromides

• Changdong Shao,
• Chen Ma,
• Li Li,
• Jingyi Liu,
• Yanan Shen,
• Chen Chen,
• Qionglin Yang,
• Tianyi Xu,
• Zhengsong Hu,
• Yuhe Kan and
• Tingting Zhang

Beilstein J. Org. Chem. 2024, 20, 155–161, doi:10.3762/bjoc.20.14

• . Reaction conditions: 1a (0.2 mmol), 2 (0.8 mmol), Cu(OAc)2·H2O (20 mol %), K2CO3 (0.2 mmol), DMSO (1.0 mL), stirred under air at 100 ºC for 12 h. Isolated yield. Further substrate scope investigations and gram-scale application. Control experiments and proposed mechanism. Optimization of the reaction

Visible-light-induced radical cascade cyclization: a catalyst-free synthetic approach to trifluoromethylated heterocycles

• Chuan Yang,
• Wei Shi,
• Jian Tian,
• Lin Guo,
• Yating Zhao and
• Wujiong Xia

Beilstein J. Org. Chem. 2024, 20, 118–124, doi:10.3762/bjoc.20.12

• most suitable CF3 radical source. Further optimization involved screening the substrates’ ratios, which revealed that an excess of substrate 1a resulted in improved yields. Finally, experimenting with anhydrous DCM as the solvent showed that anhydrous conditions were not necessary for the reaction

• derivatives. UV–vis spectra of substrates; [1a] 0.33 M, [2a] 0.11 M. Selected works for the construction of dihydropyrido[1,2-a]indolones and current methodology. Substrate scope of the cascade reaction. Radical trapping experiment. Plausible reaction mechanism. Optimization of reaction conditions.a

Electron-beam-promoted fullerene dimerization in nanotubes: insights from DFT computations

• Laura Abella,
• Gerard Novell-Leruth,
• Josep M. Ricart,
• Josep M. Poblet and
• Antonio Rodríguez-Fortea

Beilstein J. Org. Chem. 2024, 20, 92–100, doi:10.3762/bjoc.20.10

• ). Structure of dimer 5B-Cs•+ found in the metadynamics, however, is not a minimum and leads to dimer 3B-Cs•+ upon geometry optimization. C–C distances of the new bonds are within the range 1.53–1.71 Å. For dimer 1-Cs•+, the two distances are equivalent (1.587 Å) as they are the six distances for HPR-Cs

Preparing a liquid crystalline dispersion of carbon nanotubes with high aspect ratio

• Keiko Kojima,
• Nodoka Kosugi,
• Hirokuni Jintoku,
• Kazufumi Kobashi and
• Toshiya Okazaki

Beilstein J. Org. Chem. 2024, 20, 52–58, doi:10.3762/bjoc.20.7

• this study. On the other hand, despite higher L/D, the CNT orientation in the film prepared from the dispersion was comparable to the previous study. This suggests that further optimization of the deposition process is necessary to create highly oriented CNT films. Results and Discussion To prepare

• consistent with the Onsager theory. On the other hand we found that the order parameter of the DWCNT film, obtained from the LC dispersion, was nearly identical to that of the film composed of lower L/D SWCNTs [23]. Further optimization of experimental conditions, including viscosity of the dispersion and

Cycloaddition reactions of heterocyclic azides with 2-cyanoacetamidines as a new route to C,N-diheteroarylcarbamidines

• Pavel S. Silaichev,
• Tetyana V. Beryozkina,
• Vsevolod V. Melekhin,
• Valeriy O. Filimonov,
• Andrey N. Maslivets,
• Vladimir G. Ilkin,
• Wim Dehaen and
• Vasiliy A. Bakulev

Beilstein J. Org. Chem. 2024, 20, 17–24, doi:10.3762/bjoc.20.3

• -diaminoacrylonitriles 1 with heteroaryl azides (HetN3) 2 [16] leading to 5-amino-1,2,3-triazole-4-N-heteroarylcarbimidamides 3 (Scheme 1C). Results and Discussion Optimization of the reaction of amidine 1a with azide 2a We initiated the study by investigating a model reaction involving the cycloaddition of 3-amino-3

• (method A)a; 1 (0.5 mmol), 2 (0.5 mmol), NaOH (0.5 mmol), EtOH (2 mL), 0 °C → rt, 30 min (method B)b. Proposed mechanism for the formation of triazoles 3. Optimization of the reaction of amidine 1a with 6-azidopyrimidine-2,4-dione 2a.a Cytotoxicity index (IC50 ± SE) in µM of the studied compounds on human

Synthesis of N-acyl carbazoles, phenoxazines and acridines from cyclic diaryliodonium salts

• Nils Clamor,
• Mattis Damrath,
• Thomas J. Kuczmera,
• Daniel Duvinage and
• Boris J. Nachtsheim

Beilstein J. Org. Chem. 2024, 20, 12–16, doi:10.3762/bjoc.20.2

• iodane. bphenoxazines 3b–e required a higher reaction temperature of 135 °C. Optimization of reaction conditions.a Supporting Information Supporting Information File 22: Experimental part. Funding Funding for NC was provided by DFG project NA955/3-1.

1-Butyl-3-methylimidazolium tetrafluoroborate as suitable solvent for BF₃: the case of alkyne hydration. Chemistry vs electrochemistry

• Marta David,
• Elisa Galli,
• Richard C. D. Brown,
• Marta Feroci,
• Fabrizio Vetica and
• Martina Bortolami

Beilstein J. Org. Chem. 2023, 19, 1966–1981, doi:10.3762/bjoc.19.147

• anion. Subsequently, we extended the method to different internal and terminal alkynes. Finally, we studied the reaction in the electrogenerated BF3/BMIm-BF4 system, comparing the results with those obtained with the chemical route (BF3·Et2O). Results and Discussion Optimization of the reaction

• reused up to five times, without adversely affecting the reaction yields. Screening of different ionic liquids as media for the hydration of diphenylacetylene After the optimization of the reaction conditions in BMIm-BF4, different ILs were considered as alternative solvent (Table 2 and Table 3). All the

• BMIm-BF4 catalysed by BF3·Et2O (blue) and by electrogenerated BF3 (orange). Anodic oxidation of tetrafluoroborate anion. Optimization of the reaction conditions for hydration of diphenylacetylene (1a)a. Structure of the ILs used as solvent for the hydration reaction of diphenylacetylene (1a). Hydration

Thienothiophene-based organic light-emitting diode: synthesis, photophysical properties and application

• Recep Isci and
• Turan Ozturk

Beilstein J. Org. Chem. 2023, 19, 1849–1857, doi:10.3762/bjoc.19.137

• . The high thermal stability is profitable for the preparation of stable and durable OLED devices. Computational chemistry Ground-state geometry optimization of DMB-TT-TPA (8) was performed using density functional theory (DFT) calculations with the Gaussian 16 software at the B3LYP/6-31G (d,p) level

Selectivity control towards CO versus H₂ for photo-driven CO₂ reduction with a novel Co(II) catalyst

• Lisa-Lou Gracia,
• Philip Henkel,
• Olaf Fuhr and
• Claudia Bizzarri

Beilstein J. Org. Chem. 2023, 19, 1766–1775, doi:10.3762/bjoc.19.129

• ). Unfortunately, also the generation of H2 increased with the concentration of HFIP, lowering the selectivity to 55%. Nevertheless, these results are promising, and further optimization studies are necessary to achieve high efficiencies and selectivity at the same time. Conclusion We presented a novel Co(II

• the selectivity towards the two electron-reduction product of CO2, carbon monoxide. We successfully achieved a selectivity of 97% with the use of TEA (12.5%) instead of TEOA. The following optimization studies allowed us to tune the efficiency for CO production with a maximum TON of 86, after 15 h of