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Search for "derivatives" in Full Text gives 2815 result(s) in Beilstein Journal of Organic Chemistry. Showing first 200.

Antibiofilm and cytotoxic metabolites from the entomopathogenic fungus Samsoniella aurantia

  • Rita Toshe,
  • Syeda J. Khalid,
  • Blondelle Matio Kemkuignou,
  • Esteban Charria-Girón,
  • Paul Eckhardt,
  • Birthe Sandargo,
  • Kunlapat Nuchthien,
  • J. Jennifer Luangsa-ard,
  • Till Opatz,
  • Hedda Schrey,
  • Sherif S. Ebada and
  • Marc Stadler

Beilstein J. Org. Chem. 2025, 21, 327–339, doi:10.3762/bjoc.21.23

Graphical Abstract
  • and five 2-pyridone derivatives that revealed potential antibiofilm activity against Staphylococcus aureus biofilms [7]. These results encouraged us to explore a member of the Cordycipitaceae, in the genus Samsoniella that was segregated from Akanthomyces based on morphological and molecular evidence
  • δC 34.2 (C-12) and 29.7 (C-13), respectively. The HMBC correlations (Figure 3) indicated that the side chain in 1 ends as –C(CH3)=CH-CH(CH3)-CH2-CH3 resembling those from farinosones A/B [8] and tenellin derivatives [10][11]. The relative configuration of 1 was elucidated based on its ROESY spectrum
  • groups ascribed to H3-14 and H3-15 together with a diastereotopic methylene group at δH 1.25/1.36 (H2-13) confirming the depicted end of the aliphatic sidechain as –C(CH3)=CH-CH(CH3)-CH2-CH3 similar to that in farinosones A/B [8] and tenellin derivatives [10][11]. To establish the absolute configuration
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Published 11 Feb 2025

Red light excitation: illuminating photocatalysis in a new spectrum

  • Lucas Fortier,
  • Corentin Lefebvre and
  • Norbert Hoffmann

Beilstein J. Org. Chem. 2025, 21, 296–326, doi:10.3762/bjoc.21.22

Graphical Abstract
  • photocatalysts, such as helical carbenium ions and advanced nitrobenzofuran derivatives for applications in phototherapy and controlled drug release, underscoring the potential of red-light photocatalysis in biomedicine. Review Red-light photocatalysis with metal-based complexes Metal-based complexes naturally
  • properties of metal complexes. Phthalocyanins, porphyrins, and their derivatives exemplify this, as their rigid macrocyclic structures enable strong absorption in the visible to NIR regions, making them appealing for photoredox catalysis applications. For instance, ruthenium phthalocyanin complexes have
  • emerged as potent catalysts for red-light-mediated photoreactions. Furuyama et al. demonstrated that a ruthenium phthalocyanin complex could catalyze trifluoromethylation reactions of styrene derivatives 18 with either CF3SO2Cl or Umemoto’s reagent 19 under red-light irradiation without the need for
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Published 07 Feb 2025

Molecular diversity of the reactions of MBH carbonates of isatins and various nucleophiles

  • Zi-Ying Xiao,
  • Jing Sun and
  • Chao-Guo Yan

Beilstein J. Org. Chem. 2025, 21, 286–295, doi:10.3762/bjoc.21.21

Graphical Abstract
  • . Diverse functionalized 3-substituted oxindole derivatives were successfully prepared in satisfactory yields and with high diastereoselectivity. In addition, the base-promoted dimerization of MBH carbonates of isatin afforded the ethylene-bridged bis(3-methylene)oxindole derivatives with nearly 4:1
  • biologically important 3-substituted and spirooxindole derivatives [5][6][7]. The unique molecular architecture and remarkable pharmacological activities have made spirooxindole one of the hottest synthetic targets with fruitful chemical and steric selectivity [8][9][10][11][12][13][14][15]. In recent years
  • ]. In the presence of a Lewis base, MBH carbonates of isatins can be easily converted to activated allylic ylides, which in turn can undergo allylic substitution and annulation reactions to give diverse 3-substituted and spirooxindole derivatives [36][37][38][39][40][41]. Inspired by these elegant
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Published 06 Feb 2025

Synthesis and characterizations of highly luminescent 5-isopropoxybenzo[rst]pentaphene

  • Islam S. Marae,
  • Jingyun Tan,
  • Rengo Yoshioka,
  • Zakaria Ziadi,
  • Eugene Khaskin,
  • Serhii Vasylevskyi,
  • Ryota Kabe,
  • Xiushang Xu and
  • Akimitsu Narita

Beilstein J. Org. Chem. 2025, 21, 270–276, doi:10.3762/bjoc.21.19

Graphical Abstract
  • by scanning electron microscopy. The intriguing optical properties of BPP and its derivatives may lead to their application as fluorophores. Keywords: benzo[rst]pentaphene; intramolecular charge transfer; nanocrystals; photoluminescence; polycyclic aromatic hydrocarbon; Introduction Polycyclic
  • facile access to BPP was reported by Amsharov and co-workers through the so-called "dehydrative π-extension (DPEX)” reaction [12]. However, functionalized derivatives of BPP have scarcely been explored in comparison to the extensive studies on the derivatives of other PAHs, such as pyrene [15][16][17
  • -substituted derivatives [21][22]. In comparison to the absorption spectrum of BPP 2, this lowest-energy absorption band of BPP-OiPr 3 was red-shifted by ≈26 nm, which marked the inductive and resonance effects of the electron-donating isopropyloxy group with lone pairs of electrons, raising the HOMO level
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Published 04 Feb 2025

Three-component reactions of conjugated dienes, CH acids and formaldehyde under diffusion mixing conditions

  • Dmitry E. Shybanov,
  • Maxim E. Kukushkin,
  • Eugene V. Babaev,
  • Nikolai V. Zyk and
  • Elena K. Beloglazkina

Beilstein J. Org. Chem. 2025, 21, 262–269, doi:10.3762/bjoc.21.18

Graphical Abstract
  • , which should significantly reduce undesirable polycondensations involving CH2O as well as polymerization of the intermediately formed methylidene derivatives. In this work, we generated methylidene adducts by formaldehyde condensation under diffusion mixing conditions in three-component reactions with
  • various CH acid derivatives and conjugated dienes (cyclopentadiene, 1,3-cyclohexadiene, 2,3-dimethylbutadiene and isoprene), leading to [4 + 2]-cycloaddition adducts (Scheme 1). It should be noted that in previous works describing three-component reactions of carbonyl compounds, conjugated dienes and
  • conditions, we studied the possibility of generating active methylidene derivatives from malonic ester, Meldrum's acid, cyanoacetic acid ester, acetoacetic ester, acetylacetone and 1,3-diphenylpropane-1,3-dione (1). We found that, with the exception of malonic ester, all compounds reacted with formaldehyde
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Published 04 Feb 2025

Synthesis of disulfides and 3-sulfenylchromones from sodium sulfinates catalyzed by TBAI

  • Zhenlei Zhang,
  • Ying Wang,
  • Xingxing Pan,
  • Manqi Zhang,
  • Wei Zhao,
  • Meng Li and
  • Hao Zhang

Beilstein J. Org. Chem. 2025, 21, 253–261, doi:10.3762/bjoc.21.17

Graphical Abstract
  • importance. In the field of disulfide synthesis, the conventional approach mainly involves oxidizing thiols to form disulfides. This process employs various oxidation agents, which can be categorized as nonmetallic and metal derivatives [12][13][14][15][16]. Over the past few years, the implementation of
  • (sp2)–H radical sulfenylation of enaminones or chromones has emerged as a popular strategy using various sulfenyl precursors such as thiophenols [38][39][40], sulfonyl hydrazides [41][42], disulfides [43], KSCN [44], S8 [45], methylsulfinyl derivatives [46], sodium sulfinates [47], and thiosulfonates
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Published 03 Feb 2025

Effect of substitution position of aryl groups on the thermal back reactivity of aza-diarylethene photoswitches and prediction by density functional theory

  • Misato Suganuma,
  • Daichi Kitagawa,
  • Shota Hamatani and
  • Seiya Kobatake

Beilstein J. Org. Chem. 2025, 21, 242–252, doi:10.3762/bjoc.21.16

Graphical Abstract
  • push–pull derivatives bearing electron-donating and electron-withdrawing groups at the para-position of the benzene rings are known to exhibit very fast thermal isomerizations [53]. Velasco and co-workers also reported that a pyrimidine-based azophenol exhibits thermal back reaction on the nanosecond
  • calculations can be a powerful tool for molecular design. In this work, we newly synthesize various aza-diarylethene derivatives N3, N4, and I1–I4 with different substitution positions of the aryl group, and investigate their photochromic behaviors and thermal back reactivities as the data set for the
  • thermal back reactivities on the order of sub-ms to ms as well as N1 and N2. These thermal back reaction rates are comparable to those of diarylbenzene derivatives, hexaarylbiimidazole derivatives, and naphthopyran derivatives, which are known as fast T-type molecules [41][65][66]. Investigating the ΔH
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Published 31 Jan 2025

Visible-light-promoted radical cyclisation of unactivated alkenes in benzimidazoles: synthesis of difluoromethyl- and aryldifluoromethyl-substituted polycyclic imidazoles

  • Yujun Pang,
  • Jinglan Yan,
  • Nawaf Al-Maharik,
  • Qian Zhang,
  • Zeguo Fang and
  • Dong Li

Beilstein J. Org. Chem. 2025, 21, 234–241, doi:10.3762/bjoc.21.15

Graphical Abstract
  • derivatives exhibit improved pharmacokinetic properties [17], which has further sparked interest in their development. Consequently, constructing benzimidazoles bearing the CF2H and PhCF2 groups has garnered significant attention. However, despite this growing interest, only a limited number of research
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Published 30 Jan 2025

Heteroannulations of cyanoacetamide-based MCR scaffolds utilizing formamide

  • Marios Zingiridis,
  • Danae Papachristodoulou,
  • Despoina Menegaki,
  • Konstantinos G. Froudas and
  • Constantinos G. Neochoritis

Beilstein J. Org. Chem. 2025, 21, 217–225, doi:10.3762/bjoc.21.13

Graphical Abstract
  • synthesis was efficient and rapid as the final adducts could be isolated only by precipitation. In addition, the reactions were performed in a parallel setup using custom-made metal blocks. Specifically, thienopyrimidine and thienopyrimidone derivatives exhibit a range of biological activities, i.e
  • ., analgesia, anti-inflammation, antihypertension and many more (DB06889, DB07397, DB08777) [47][48][49][50][51][52][53][54][55][56]. Thienopyrimidone derivatives have also been used in the context of other Gewald-based MCRs in the past, but the reported diversity has been rather low [57][58][59][60]. The
  • reaction of 2 with formamide was performed within only 3 h (Scheme 3), yielding the N-substituted thienopyrimidones 5a–e in 30–99% total yield (2 steps), as well with aliphatic and (hetero)aromatic substituents. Quinoline derivatives are prevalent in nature, and many exhibit a range of biological
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Published 24 Jan 2025

Dioxazolones as electrophilic amide sources in copper-catalyzed and -mediated transformations

  • Seungmin Lee,
  • Minsuk Kim,
  • Hyewon Han and
  • Jongwoo Son

Beilstein J. Org. Chem. 2025, 21, 200–216, doi:10.3762/bjoc.21.12

Graphical Abstract
  • amidation Recently, Cao and co-workers reported the copper-catalyzed synthesis of 1,2,4-triazole derivatives via an N-acyl nitrene intermediate [76]. As illustrated in Scheme 3, dioxazolones 4 and N-iminoquinolinium ylides 5 served as reactive substrates, leading to the formation of various polycyclic 1,2,4
  • -triazole analogues 6. Both dioxazolones 4 and N-iminoquinolinium ylides 5 demonstrated excellent tolerance in this transformation. Notably, electron-rich dioxazolones exhibited slightly higher reactivity. The proposed catalytic cycle for the copper-catalyzed synthesis of 1,2,4-triazole derivatives is
  • , styrene derivatives bearing both electron-rich and electron-poor groups underwent the desired transformation with high yields and enantioselectivities (23g and 23h). However, the styrene scaffold bearing a trifluoromethyl group showed reduced enantioselectivity (23i). Styrenes containing heterocyclic
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Published 22 Jan 2025

Hydrogen-bonded macrocycle-mediated dimerization for orthogonal supramolecular polymerization

  • Wentao Yu,
  • Zhiyao Yang,
  • Chengkan Yu,
  • Xiaowei Li and
  • Lihua Yuan

Beilstein J. Org. Chem. 2025, 21, 179–188, doi:10.3762/bjoc.21.10

Graphical Abstract
  • , including pyridinium and its derivatives [40]. More importantly, it favors intermolecular π-stacking interactions with aromatic guests [48]. Herein, we report on a novel supramolecular dimerization motif in 2:2 stoichiometry using H-bonded aramide macrocycles for constructing orthogonal supramolecular
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Published 17 Jan 2025

Recent advances in electrochemical copper catalysis for modern organic synthesis

  • Yemin Kim and
  • Won Jun Jang

Beilstein J. Org. Chem. 2025, 21, 155–178, doi:10.3762/bjoc.21.9

Graphical Abstract
  • optimized conditions allowed the reaction to proceed under a constant current electrolysis at 1.5 mA for 6 hours, followed by stirring for additional 24 hours with the electricity turned off. These reaction conditions were applicable to various N-aryl-THIQ derivatives with various functional groups. Using
  • asymmetric electrocatalytic cyanophosphinoylation of vinylarenes (Figure 14) [69]. In the presence of a copper catalyst and the chiral ligand sBOX(iPr) (L8) in an electrochemical cell, these three component reactions using styrene derivatives 27, TMSCN (21), and diarylphosphine oxide 80 as starting materials
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Published 16 Jan 2025

Cu(OTf)2-catalyzed multicomponent reactions

  • Sara Colombo,
  • Camilla Loro,
  • Egle M. Beccalli,
  • Gianluigi Broggini and
  • Marta Papis

Beilstein J. Org. Chem. 2025, 21, 122–145, doi:10.3762/bjoc.21.7

Graphical Abstract
  • intermediate VIII. At this stage, the amido–copper complex IX selectively attacks the intermediate providing the 1-aryl-2-sulfonamidopropane 8. This procedure is a valuable alternative to a similar approach for the synthesis of amphetamine derivatives 9 from allyl carbamates that requires excess of Cu(OTf)2 [6
  • Biginelli reaction was carried out starting from salicylaldehyde providing hydroxyphenyl-substituted dihydropyrimidines 18 [30]. Subsequently, the regioselective oxidation of the dihydropyrimidine ring in the presence of CAN allowed the formation of new pyrimidinone derivatives 19. The efficacy of Cu(OTf)2
  • , reacts with an enol species activated by the copper catalyst, affording the final product. The same research group reported an extension of this study by starting from arylacetylenes instead of arylketones [42]. Imidazo[1,2-a]pyridine derivatives 33 can be achieved by Cu(OTf)2-catalyzed multicomponent
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Published 14 Jan 2025

Recent advances in organocatalytic atroposelective reactions

  • Henrich Szabados and
  • Radovan Šebesta

Beilstein J. Org. Chem. 2025, 21, 55–121, doi:10.3762/bjoc.21.6

Graphical Abstract
  • compounds comprising a stereogenic plane or axis is much less developed. Axially chiral compounds are well known as chiral ligands in asymmetric catalysis, with notable examples of binaphthyl-based derivatives such as BINAP, SEGPHOS, or binaphthyl-based phosphoric acid derivatives, which are among the
  • reacted with aminoarylaldehydes 5 to form axially chiral 2-arylquinoline derivatives 6 (Scheme 2). Using the pyrrolidine derivative C2 as the most efficient organocatalyst, a range of quinoline derivatives were obtained in high yields and enantiomeric purities. The postulated mechanism consists of iminium
  • was carried out to provide the final biaryl products 17. In a related strategy, Hayashi´s team realized an organocatalytic Michael/aldol cascade leading to chiral dihydronaphthalene derivatives 20a–e [25]. Through a series of one-pot reactions, aromatization was achieved with concomitant central-to
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Published 09 Jan 2025

Facile one-pot reduction of β-nitrostyrenes to phenethylamines using sodium borohydride and copper(II) chloride

  • Laura D’Andrea and
  • Simon Jademyr

Beilstein J. Org. Chem. 2025, 21, 39–46, doi:10.3762/bjoc.21.4

Graphical Abstract
  • atmosphere, special precautions, and with isolated yields up to 60% [14][15]. Due to the formation of side products, final purification of the amino derivatives requires the use of either multiple separation techniques, chromatography, or distillation [15][16][17][18] (Scheme 1). Differently from lithium
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Published 07 Jan 2025

Synthesis, characterization, and photophysical properties of novel 9‑phenyl-9-phosphafluorene oxide derivatives

  • Shuxian Qiu,
  • Duan Dong,
  • Jiahui Li,
  • Huiting Wen,
  • Jinpeng Li,
  • Yu Yang,
  • Shengxian Zhai and
  • Xingyuan Gao

Beilstein J. Org. Chem. 2024, 20, 3299–3305, doi:10.3762/bjoc.20.274

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  • Chemistry & Environmental Engineering, Anyang Institute of Technology, Anyang 455000, China 10.3762/bjoc.20.274 Abstract A novel series of D−A−D-type 9-phenyl-9-phosphafluorene oxide (PhFlOP) derivatives was prepared and is reported herein. The synthetic protocol involved 5 steps from commercially
  • HRMS spectrometry were in full agreement with the expected structures, and single-crystal X-ray diffraction analysis was conducted to confirm the structure of compound 7-H. Moreover, the photophysical properties of these PhFlOP derivatives were determined by UV–vis absorption and photoluminescence
  • acceptor group in TADF emitters, indicating great potential for the development of highly efficient TADF molecules. In 2019, Nishida and co-workers prepared 5 D–A–D-type PhFlOP derivatives with electron-donating diarylamine or carbazole moieties in positions 2 and 8. They conducted optical and
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Published 30 Dec 2024

Synthesis of acenaphthylene-fused heteroarenes and polyoxygenated benzo[j]fluoranthenes via a Pd-catalyzed Suzuki–Miyaura/C–H arylation cascade

  • Merve Yence,
  • Dilgam Ahmadli,
  • Damla Surmeli,
  • Umut Mert Karacaoğlu,
  • Sujit Pal and
  • Yunus Emre Türkmen

Beilstein J. Org. Chem. 2024, 20, 3290–3298, doi:10.3762/bjoc.20.273

Graphical Abstract
  • -catalyzed annulation reaction between bromo-chloronaphthalene dicarboximides 6 and heteroarylboronic esters that enabled the syntheses of acenaphthylene-fused thiophene and indole derivatives 7 having donor-acceptor units (Scheme 1a) [40]. In 2021, Jin and co-workers developed an elegant Pd-catalyzed
  • -diiodonaphthalene (12) and thiophene-3-ylboronic acid and ester derivatives 17 under the optimized conditions reported in our previous work (Table 1) [43]. Gratifyingly, the reaction worked smoothly with the use of thiophene-3-ylboronic acid (17a) to give acenaphtho[1,2-b]thiophene (15a) in 76% yield when Pd(dppf
  • multi-substituted benzo[j]fluoranthene derivatives, which have the potential to be useful in natural product synthesis. However, all oxygens in compound 18 are protected as methyl ethers, and therefore, demethylating one or some of these methoxy groups selectively is anticipated to be extremely
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Published 23 Dec 2024

Reactivity of hypervalent iodine(III) reagents bearing a benzylamine with sulfenate salts

  • Beatriz Dedeiras,
  • Catarina S. Caldeira,
  • José C. Cunha,
  • Clara S. B. Gomes and
  • M. Manuel B. Marques

Beilstein J. Org. Chem. 2024, 20, 3281–3289, doi:10.3762/bjoc.20.272

Graphical Abstract
  • reactivity, yielding numerous derivatives with wide applications [2][3][4][6][7][8]. Their enhanced stability, compared to other HIRs, is due to: (i) the molecular geometry, which allows better overlap between the non-bonding electrons of the central iodine atom and the π-orbitals of the aromatic ring [2][9
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Published 19 Dec 2024

Giese-type alkylation of dehydroalanine derivatives via silane-mediated alkyl bromide activation

  • Perry van der Heide,
  • Michele Retini,
  • Fabiola Fanini,
  • Giovanni Piersanti,
  • Francesco Secci,
  • Daniele Mazzarella,
  • Timothy Noël and
  • Alberto Luridiana

Beilstein J. Org. Chem. 2024, 20, 3274–3280, doi:10.3762/bjoc.20.271

Graphical Abstract
  • functionalization (LSF) of peptide scaffolds. α,β-Unsaturated amino acids like dehydroalanine (Dha) derivatives have emerged as particularly useful structures, as the electron-deficient olefin moiety can engage in late-stage functionalization reactions, like a Giese-type reaction. Cheap and widely available
  • derivatives. Upon abstraction of a hydride from tris(trimethylsilyl)silane (TTMS) by an excited benzophenone derivative, the formed silane radical can undergo a XAT with an alkyl bromide to generate an alkyl radical. Consequently, the alkyl radical undergoes a Giese-type reaction with the Dha derivative
  • photocatalyst (Figure 1d) [25]. Noël et al. [26] have further extended this approach to include alkyl bromides (Figure 1e) [26]. Despite the effectiveness of the photolysis, benzophenone derivatives have also been shown to enhance the productivity of silane-mediated conjugate additions, using alkyl halides [27
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Published 17 Dec 2024

Efficient synthesis of fluorinated triphenylenes with enhanced arene–perfluoroarene interactions in columnar mesophases

  • Yang Chen,
  • Jiao He,
  • Hang Lin,
  • Hai-Feng Wang,
  • Ping Hu,
  • Bi-Qin Wang,
  • Ke-Qing Zhao and
  • Bertrand Donnio

Beilstein J. Org. Chem. 2024, 20, 3263–3273, doi:10.3762/bjoc.20.270

Graphical Abstract
  • organolithium derivatives 2,2'-dilithio-4,4',5,5'-tetraalkoxy-1,1'-biphenyl (2Li-BPn). In a continuation of this study, aiming at testing the limits of the reaction and providing a large diversity of structures, a structurally related series of compounds is reported here, namely 1,2,4-trifluoro-6,7,10,11
  • -tetraalkoxy-3-(perfluorophenyl)triphenylenes (Fn). They were obtained by reacting the above mentioned 2,2’-dilithiobiphenyl derivatives with decafluorobiphenyl, C6F5–C6F5. These compounds differ from the previously reported series, 1,2,4-trifluoro-6,7,10,11-tetraalkoxy-3-aryltriphenylenes (PHn), solely by the
  • derivatives and the antiparallel stacking mode into columnar structures stabilized by arene–perfluoroarene intermolecular interactions were confirmed by the single-crystal structure of the alkoxy-free side chain analog, i.e., 1,2,4-trifluoro-3-(perfluorophenyl)triphenylene (F). UV–vis absorption and
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Published 16 Dec 2024

Intramolecular C–H arylation of pyridine derivatives with a palladium catalyst for the synthesis of multiply fused heteroaromatic compounds

  • Yuki Nakanishi,
  • Shoichi Sugita,
  • Kentaro Okano and
  • Atsunori Mori

Beilstein J. Org. Chem. 2024, 20, 3256–3262, doi:10.3762/bjoc.20.269

Graphical Abstract
  • % yield, respectively. The related reaction is also carried out with amides of non-pyridine derivatives terephthal- and benzamides to afford multiply fused heterocyclic compounds in 81% and 89% yields, respectively. Keywords: intramolecular C–H arylation; multiply fused heterocycles; palladium acetate
  • ][7] are found in a variety of advanced materials [8][9] and biologically important molecules [10][11][12]. A wide range of pyridine derivatives have been employed as extractants of metal ions through chelation [13]. Phenanthrolines, a class of pyridine derivatives, have attracted attention for the
  • effective to afford 2a in 94% yield. The reaction was then carried out with several pyridine derivatives including amide derivatives composed of 6-methylpicoline (1b) and unsubstituted picoline (1c) as summarized in Table 2. When the reaction was examined in the absence of a phosphine ligand, the yields of
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Published 13 Dec 2024

Non-covalent organocatalyzed enantioselective cyclization reactions of α,β-unsaturated imines

  • Sergio Torres-Oya and
  • Mercedes Zurro

Beilstein J. Org. Chem. 2024, 20, 3221–3255, doi:10.3762/bjoc.20.268

Graphical Abstract
  • enables the synthesis of structurally distinct cyclic derivatives which are difficult to access by other methodologies, using an efficient and atom-economical path from simple precursors. In recent years several asymmetric catalytic cyclization strategies have been accomplished for the construction of N
  • cyclic derivatives. Conjugated imines are usually synthesized from the corresponding carbonyl precursors by reaction with a sulfonamide in the presence of Lewis acids and a dehydrating agent such as molecular sieves [3]. Also, recently a palladium-catalyzed dehydrogenation of aliphatic imines was
  • example. This review discusses different examples involving IEDADA reactions and other cyclizations, with a special focus on the mode of action of the organocatalysts, and aims to show the synthetic applicability of the formed cyclic derivatives. The three non-covalent organocatalysts which will be
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Published 10 Dec 2024

Ceratinadin G, a new psammaplysin derivative possessing a cyano group from a sponge of the genus Pseudoceratina

  • Shin-ichiro Kurimoto,
  • Kouta Inoue,
  • Taito Ohno and
  • Takaaki Kubota

Beilstein J. Org. Chem. 2024, 20, 3215–3220, doi:10.3762/bjoc.20.267

Graphical Abstract
  • ]undeca-2,7,9-trien-4-ol moiety classified as psammaplysin derivatives. About 50 psammaplysin derivatives have been identified so far [2][3]. Among bromotyrosine alkaloids, the psammaplysin derivatives are particularly intriguing due to their structural complexity and biological activities. Psammaplysin
  • derivatives exhibit a range of bioactivities, including antibacterial, anticancer, antimalarial, and antiviral effects. Since the discovery of the first psammaplysin derivative, psammaplysin A [4][5], these alkaloids have been recognized as challenging targets for total synthesis. The absolute configuration
  • have identified various bioactive bromotyrosine alkaloids [8]. Previously, we isolated two psammaplysin derivatives, ceratinadins E and F, containing two or three 11-N-methylmoloka’iamine units, from the Okinawan marine sponge Pseudoceratina sp. [9]. Further investigation of this sponge has led to the
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Published 09 Dec 2024

Synthesis of 2H-azirine-2,2-dicarboxylic acids and their derivatives

  • Anastasiya V. Agafonova,
  • Mikhail S. Novikov and
  • Alexander F. Khlebnikov

Beilstein J. Org. Chem. 2024, 20, 3191–3197, doi:10.3762/bjoc.20.264

Graphical Abstract
  • derivatives [1]. In particular, the catalytic isomerization of 5-chloroisoxazoles allows the generation of azirine-2-carbonyl chlorides, which can be easily converted into a variety of azirine-2-carboxylic acid derivatives by reactions with nucleophilic reagents. Using this approach, numerous 2-(1H-pyrazol-1
  • -carboxylic acid derivatives are not only valuable synthetic building blocks [3][4][5][6][7][8][9][10][11] but also show useful biological activities [12][13][14][15][16][17][18]. Although many 2,2-bifunctionalized azirines have been synthesized [3][4][5][6][7][8][9][10][11], the synthesis of only one 2H
  • only one azirine-2,2-dicarboxylic acid derivative from a certain isoxazole precursor. Herein, we would like to report a method for the synthesis of 2H-azirine-2,2-dicarboxylic acids and their various derivatives from a single starting material, 3-substituted 2H-azirine-2,2-dicarbonyl dichloride 2, via
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Published 05 Dec 2024

Direct trifluoroethylation of carbonyl sulfoxonium ylides using hypervalent iodine compounds

  • Radell Echemendía,
  • Carlee A. Montgomery,
  • Fabio Cuzzucoli,
  • Antonio C. B. Burtoloso and
  • Graham K. Murphy

Beilstein J. Org. Chem. 2024, 20, 3182–3190, doi:10.3762/bjoc.20.263

Graphical Abstract
  • % yield, and comparable yields were observed for the p-tolyl and p-chlorophenyl derivatives 3n and 3o. A slight increase in yield was found with the p-anisyl derivative (3p, 61% yield), whereas the yield decreased when the arene was appended with an electron-withdrawing CF3 group (3q, 45% yield). Though
  • polyfluoroalkylated derivatives in moderate to very good (45–92%) yields. It is nonetheless crucial to underscore that the reaction developed herein was ineffective with aromatic and aliphatic variants of both keto and imino sulfoxonium ylides, and no reaction was observed in any of the attempts (see Supporting
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Published 04 Dec 2024
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