Synthesis of N-doped chiral macrocycles by regioselective palladium-catalyzed arylation

• Shuhai Qiu and
• Junzhi Liu

Beilstein J. Org. Chem. 2025, 21, 1917–1923, doi:10.3762/bjoc.21.149

• asymmetric geometry due to the fusion of the pyrene unit (Figure 2c). The two pyrene units are oriented antiparallel, which is distinctive from that observed in 3a and MC2. Notably, the pyrene-fused moiety is highly curved with a bending angle of 85.3° as defined by the angle of the planes of the terminal

• absorption maximum of MC1 is more redshifted by 42 nm compared to MC2, which is attributed to the extended conjugation after the fusion of one pyrene unit. Similarly, both MC1 and MC2 have higher ΦF values of 0.45 and 0.69 than compound MC3 (ΦF = 0.13). The optical energy bandgaps were determined to be 2.48

Research progress on calixarene/pillararene-based controlled drug release systems

• Liu-Huan Yi,
• Jian Qin,
• Si-Ran Lu,
• Liu-Pan Yang,
• Li-Li Wang and
• Huan Yao

Beilstein J. Org. Chem. 2025, 21, 1757–1785, doi:10.3762/bjoc.21.139

3-Aryl-2H-azirines as annulation reagents in the Ni(II)-catalyzed synthesis of 1H-benzo[4,5]thieno[3,2-b]pyrroles

• Julia I. Pavlenko,
• Pavel A. Sakharov,
• Anastasiya V. Agafonova,
• Derenik A. Isadzhanyan,
• Alexander F. Khlebnikov and
• Mikhail S. Novikov

Beilstein J. Org. Chem. 2025, 21, 1595–1602, doi:10.3762/bjoc.21.123

• reactions of heteroaromatics with azirines are known only for 2-chloro- and 2-sulfanylpyridines [14][15], which result in the formation of imidazo[1,2-a]pyridines (Scheme 1, reactions 4 and 5). To the best of our knowledge, no successful methods enabling the fusion of a pyrrole or azole ring to a 5-membered

Synthesis of an aza[5]helicene-incorporated macrocyclic heteroarene via oxidation of an o-phenylene-pyrrole-thiophene icosamer

• Yusuke Matsuo,
• Aoi Nakagawa,
• Shu Seki and
• Takayuki Tanaka

Beilstein J. Org. Chem. 2025, 21, 1561–1567, doi:10.3762/bjoc.21.119

• , Japan 10.3762/bjoc.21.119 Abstract The intramolecular oxidative fusion reaction of macrocyclic heteroaromatic arrays has provided strained polycyclic heteroaromatic macrocycles as promising functional molecules. In this study, we prepared an ortho-phenylene-pyrrole-thiophene hybrid icosamer, as the

• largest cyclic array in the series. The oxidative fusion reaction with [bis(trifluoroacetoxy)iodo]benzene (PIFA) afforded a cyclophane-type aza[5]helicene-incorporated macrocycle, the structure of which was unambiguously revealed by X-ray diffraction analysis. Its optical properties have been investigated

• thiophene units [24][25]. The influence of heteroaromatic positioning on the reaction outcome has been rationalized in our previous work [25]. As a further extension of this molecular design, herein we report the synthesis of an o-phenylene-pyrrole-thiophene hybrid icosamer and its oxidative fusion to yield

Advances in nitrogen-containing helicenes: synthesis, chiroptical properties, and optoelectronic applications

• Meng Qiu,
• Jing Du,
• Nai-Te Yao,
• Xin-Yue Wang and
• Han-Yuan Gong

Beilstein J. Org. Chem. 2025, 21, 1422–1453, doi:10.3762/bjoc.21.106

• , Tanaka’s group synthesized benzannulated double aza[9]helicene 32a and its alkylated derivatives 32b and 32c via a one-pot oxidative fusion strategy [46]. Compared to the parent compound 32a (ΦF = 0.07), compounds 32b and 32c exhibit significantly enhanced ΦF (0.35), red-shifted absorption bands, and |gabs

Recent advances and future challenges in the bottom-up synthesis of azulene-embedded nanographenes

• Bartłomiej Pigulski

Beilstein J. Org. Chem. 2025, 21, 1272–1305, doi:10.3762/bjoc.21.99

• constructing various benzenoid polycyclic aromatic hydrocarbons (PAHs) [9]. So it is not a surprise that such fusion reactions were used in construction of azulene embedded in various nanographenes. However, when applied to complex and sterically crowded precursors, the reaction often involves a degree of

• 114 and 115 exhibit NIR optical absorption, with azulene subunits that retain their aromatic properties. Intramolecular C–H arylation: The intramolecular, palladium-catalysed C–H arylation can also serve as an effective tool for the fusion of azulene-embedded nanographenes. Liu and co-workers reported

• | values of helicenes in the visible range. Miscellaneous reactions: The scope of reactions that can be used as the final fusion step when azulene-containing precursors are employed is not limited to those described above. A synthetic strategy involving condensation followed by the reaction of the

Silver(I) triflate-catalyzed post-Ugi synthesis of pyrazolodiazepines

• Muhammad Hasan,
• Anatoly A. Peshkov,
• Syed Anis Ali Shah,
• Andrey Belyaev,
• Chang-Keun Lim,
• Shunyi Wang and
• Vsevolod A. Peshkov

Beilstein J. Org. Chem. 2025, 21, 915–925, doi:10.3762/bjoc.21.74

• attention due to their modular hydrogen bond donor/acceptor profile that can be tuned by varying the nitrogen position and the degree of unsaturation as well as by fusion with other rings [3]. Benzodiazepines, which contain a seven-membered diazepine core fused to a benzene ring, are recognized as

Synthesis of HBC fluorophores with an electrophilic handle for covalent attachment to Pepper RNA

• Raphael Bereiter and
• Ronald Micura

Beilstein J. Org. Chem. 2025, 21, 727–735, doi:10.3762/bjoc.21.56

• fluorescent protein (GFP), has revolutionized genetics by providing highly accurate real-time detection of fusion proteins in vitro and in vivo [1]. Pioneering work on GFP-tagged proteins for real-time monitoring of gene expression was first reported by Chalfie and co-workers in 1994 [2]. For a long time

Photocatalyzed elaboration of antibody-based bioconjugates

• Marine Le Stum,
• Eugénie Romero and
• Gary A. Molander

Beilstein J. Org. Chem. 2025, 21, 616–629, doi:10.3762/bjoc.21.49

• tremendous promise within the domains of biotechnology and biomedical research [57][58]. To date, such entities have most often been formulated from the expression of fusion proteins, although more recently post-translational protein–protein conjugation has been recognized as a means to access such

Unraveling aromaticity: the dual worlds of pyrazole, pyrazoline, and 3D carborane

• Zahra Noori,
• Miquel Solà,
• Clara Viñas,
• Francesc Teixidor and
• Jordi Poater

Beilstein J. Org. Chem. 2025, 21, 412–420, doi:10.3762/bjoc.21.29

• Barcelona, Spain 10.3762/bjoc.21.29 Abstract A new series of o-carborane-fused pyrazoles has been recently successfully synthesized. This fusion was expected to create a hybrid 3D/2D aromatic system, combining the 3D aromaticity of o-carborane with the 2D aromaticity of pyrazole. However, while the boron

• the n + 1 MOs of the carborane prevents significant electronic delocalization between the two fused components. This contrasts with the fusion of pyrazole and benzene to form indazole, where both rings maintain their 2D aromaticity. Our findings demonstrate that the peripheral σ-aromaticity of

• [37]. A priori, this fusion between 3D aromatic o-carborane and 2D aromatic pyrazole should give a 3D/2D aromatic o-carborane-fused pyrazole. However, we recently demonstrated that, unlike many 2D/2D and 3D/3D aromatic fusions that retain their aromaticity, a 3D/2D aromatic combination is not feasible

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

Oxidation of [3]naphthylenes to cations and dications converts local paratropicity into global diatropicity

• Abel Cárdenas,
• Zexin Jin,
• Yong Ni,
• Jishan Wu,
• Yan Xia,
• Francisco Javier Ramírez and
• Juan Casado

Beilstein J. Org. Chem. 2025, 21, 277–285, doi:10.3762/bjoc.21.20

• consists of a single band at 1704 cm−1, assigned to the ν(CC)exo-CBD vibration, which moved to 1689 cm−1 in 2•+, and to 1686 cm−1 in 22+. This continuous downshift upon oxidation is in contrast to the observed upshift in 1•+ → 12+, corroborating that the fusion topology of the two molecules determines the

• and CBD. The reliability of the values is supported by the good fit between theoretical and experimental Raman spectra (see Figures S4 and S5 in Supporting Information File 1 for the calculated spectra of the oxidized species). As regarding the neutral species, fusion of these molecular groups

• , 0.13 mdyn/Å for m-2 and 0.31 mdyn/Å for m-1. These data evidence the sensitivity of the ν(CC)exo-CBD Raman band to the fusion topology. In summary, the force constant analysis tells us that the structural changes upon oxidation are largely localized in CBD for m-1 (marked by the zig-zag shift of the

Multicomponent reactions driving the discovery and optimization of agents targeting central nervous system pathologies

• Lucía Campos-Prieto,
• Aitor García-Rey,
• Eddy Sotelo and
• Ana Mallo-Abreu

Beilstein J. Org. Chem. 2024, 20, 3151–3173, doi:10.3762/bjoc.20.261

• strategic approach allows precise control of the stereogenic centers at the C3-position during cyclization (Scheme 16). Ugi-4CR/metal-catalyzed reaction: The fusion of MCRs with cross-coupling reactions represents an attractive approach as a result of the increased intricacy and effectiveness [62]. Moreover

Cell-free protein synthesis with technical additives – expanding the parameter space of in vitro gene expression

• Tabea Bartsch,
• Stephan Lütz and
• Katrin Rosenthal

Beilstein J. Org. Chem. 2024, 20, 2242–2253, doi:10.3762/bjoc.20.192

• workflows [45]) and performance evaluation. This is convenient because product formation and even concentration can be easily quantified measuring the fluorescence intensity. To take advantage of this, fusion proteins with sfGFP can be constructed for CFPS performance evaluation [46]. Therefore, sfGFP was

• GMP-AMP (cGAMP) are part of the innate immune response in higher eukaryotes [58]. cGAMP is therefore a promising candidate for pharmaceutical applications [59]. The successful synthesis of the fusion protein of truncated human cGAS and superfolder GFP (thscGAS-sfGFP) using the in-house E. coli-based

Natural resorcylic lactones derived from alternariol

• Joachim Podlech

Beilstein J. Org. Chem. 2024, 20, 2171–2207, doi:10.3762/bjoc.20.187

• biological activity was determined for these compounds. Pestauvicomorpholine A (34) is an exceptional hybrid metabolite with fusion of a polyketide-derived resorcylic lactone and the steroid dihydroergosterol, which was isolated from the fungus Pestalotiopsis uvicola [174]. Its structure was determined by

Computational toolbox for the analysis of protein–glycan interactions

• Ferran Nieto-Fabregat,
• Maria Pia Lenza,
• Angela Marseglia,
• Cristina Di Carluccio,
• Antonio Molinaro,
• Alba Silipo and
• Roberta Marchetti

Beilstein J. Org. Chem. 2024, 20, 2084–2107, doi:10.3762/bjoc.20.180

Chemo-enzymatic total synthesis: current approaches toward the integration of chemical and enzymatic transformations

• Ryo Tanifuji and
• Hiroki Oguri

Beilstein J. Org. Chem. 2024, 20, 1693–1712, doi:10.3762/bjoc.20.151

• utilizing Streptomyces venezuelae DHS316, developed by the same group, mediated the desosaminylation of 4 at C5 and afforded M-4365 G1 (80) in 70% yield [87]. For further oxidative modifications, they prepared the fusion proteins Tyll-RhFRED and JuvD-RhFRED, comprising P450 monooxygenases (TylI, JuvD) with

• aldehyde at the C6 sidechain. Furthermore, the fusion protein, JuvD-RhFRED, enabled regio- and diastereoselective epoxidation of the C12 double bond of macrocycles 80–82, culminating in the total synthesis of M-4365 A1 (83), M-4365 A3 (juvenimicin A4, 84), and M-4365 A2 (juvenimicin A3, 85), respectively

Methyltransferases from RiPP pathways: shaping the landscape of natural product chemistry

• Maria-Paula Schröder,
• Isabel P.-M. Pfeiffer and
• Silja Mordhorst

Beilstein J. Org. Chem. 2024, 20, 1652–1670, doi:10.3762/bjoc.20.147

• the core, the precursor is cleaved and the MT domain is presumably degraded without catalysing any further methylating reactions [98]. The OphMA fusion functions as a homodimer, with the active site of the interlocking dimers modifying the substrate peptide (Figure 7) [99]. The MT domain of OphMA is

Computation-guided scaffold exploration of 2E,6E-1,10-trans/cis-eunicellanes

• Zining Li,
• Sana Jindani,
• Volga Kojasoy,
• Teresa Ortega,
• Erin M. Marshall,
• Khalil A. Abboud,
• Sandra Loesgen,
• Dean J. Tantillo and
• Jeffrey D. Rudolf

Beilstein J. Org. Chem. 2024, 20, 1320–1326, doi:10.3762/bjoc.20.115

• natural products containing a foundational 6/10-bicyclic framework and can be divided into two main classes, cis and trans, based on the configurations of their ring fusion at C1 and C10. Previous studies on two bacterial diterpene synthases, Bnd4 and AlbS, revealed that these enzymes form cis- and trans

• family members in bacteria and plants [4], these diterpenoids have four main structural differences: the number and location of oxidized carbons, the absence or presence of transannular ether bridges, the configuration (cis or trans) of the bicyclic ring fusion, and the presence and configuration (E or Z

• Ring fusion configuration does not affect protonation-induced cyclization Our initial observation that albireticulene (2) was unstable in chloroform, resulting in two tricyclic isomers gersemienes A (5) and B (6) [7], while benditerpetriene (1) was stable [5], led us to investigate the protonation

Synthesis of indano[60]fullerene thioketone and its application in organic solar cells

• Yong-Chang Zhai,
• Shimon Oiwa,
• Shinobu Aoyagi,
• Shohei Ohno,
• Tsubasa Mikie,
• Jun-Zhuo Wang,
• Hirofumi Amada,
• Koki Yamanaka,
• Kazuhira Miwa,
• Naoyuki Imai,
• Takeshi Igarashi,
• Itaru Osaka and
• Yutaka Matsuo

Beilstein J. Org. Chem. 2024, 20, 1270–1277, doi:10.3762/bjoc.20.109

• Fusion, Resonac Corporation, 5-1 Okawa-cho, Kawasaki-ku, Kawasaki-shi, Kanagawa 210-0858, Japan Institute of Materials Innovation, Institutes for Future Society, Nagoya University, Furo-cho, Chikusa-ku, Nagoya 464-8603, Japan 10.3762/bjoc.20.109 Abstract Evaporable indano[60]fullerene ketone (FIDO) was

Research progress on the pharmacological activity, biosynthetic pathways, and biosynthesis of crocins

• Zhongwei Hua,
• Nan Liu and
• Xiaohui Yan

Beilstein J. Org. Chem. 2024, 20, 741–752, doi:10.3762/bjoc.20.68

• heterologous hosts. Xie et al. introduced a multigene expression vector (GjCCD4a-GjALDH2C3-GjUGT74F8-GjUGT94E13) into N. benthamiana by using the fusion and 2A polypeptides strategy and obtained a crocin yield of 78,362 ng/g (fresh weight). The content of crocin-I (2a) and crocin-II (2b) accounted for 99% of

Genome mining of labdane-related diterpenoids: Discovery of the two-enzyme pathway leading to (−)-sandaracopimaradiene in the fungus Arthrinium sacchari

• Fumito Sato,
• Terutaka Sonohara,
• Shunta Fujiki,
• Akihiro Sugawara,
• Yohei Morishita,
• Taro Ozaki and
• Teigo Asai

Beilstein J. Org. Chem. 2024, 20, 714–720, doi:10.3762/bjoc.20.65

• AsCPS synthesized copalyl diphosphate and that AsPS then converted it to (−)-sandaracopimaradiene. Since AsPS and AsCPS have distinct domain organizations from those of known fungal TCs and are likely generated through fusion or loss of catalytic domains, our findings provide insight into the evolution

• existing in their substrates. From a structural point of view, TCs consist of α, β, and γ domains in various combinations. As these TCs are assumed to be evolved by fusion and loss of domains [2][3][4], the functional analysis of terpene synthases of unique domain organization is of great significance to

• proposed to be derived from the early fusion of bacterial class I and II enzymes [3][15]. Fungal genomes contain a number of biosynthetic genes that are attractive targets for genome mining of novel natural products and biosynthetic enzymes [16][17][18]. In our research group, genome-guided exploration of

Elucidating the glycan-binding specificity and structure of Cucumis melo agglutinin, a new R-type lectin

• Jon Lundstrøm,
• Emilie Gillon,
• Valérie Chazalet,
• Nicole Kerekes,
• Antonio Di Maio,
• Ten Feizi,
• Yan Liu,
• Annabelle Varrot and
• Daniel Bojar

Beilstein J. Org. Chem. 2024, 20, 306–320, doi:10.3762/bjoc.20.31

• ). In parallel, we also expressed CMA1 in a bacterial expression system, which allowed us to ascertain whether binding was influenced by lectin glycosylation. The full-length mature protein (6–264) and individual N- or C-terminal domains were expressed using a N-terminal fusion comprising DsbC and a

• hexa-His tag, cleavable by TEV (Tobacco etch virus) protease. Despite the presence of the DsbC signal peptide, we did not observe periplasmic localization, and all proteins were instead purified from the cytoplasm. Ni-NTA affinity chromatography followed by TEV protease cleavage of the fusion construct

Synthesis of π-conjugated polycyclic compounds by late-stage extrusion of chalcogen fragments

• Aissam Okba,
• Pablo Simón Marqués,
• Kyohei Matsuo,
• Naoki Aratani,
• Hiroko Yamada,
• Gwénaël Rapenne and
• Claire Kammerer

Beilstein J. Org. Chem. 2024, 20, 287–305, doi:10.3762/bjoc.20.30

• -resolution STM and AFM images, revealing the linear fusion of benzene rings with a zigzag edge (Figure 3), and their electronic properties were investigated at the single-molecule scale, with a particular attention devoted to the evolution of the HOMO–LUMO gap along the incremental series of acenes

Perspectives on push–pull chromophores derived from click-type [2 + 2] cycloaddition–retroelectrocyclization reactions of electron-rich alkynes and electron-deficient alkenes

• Michio Yamada

Beilstein J. Org. Chem. 2024, 20, 125–154, doi:10.3762/bjoc.20.13

• solution as well as contradictory propensity to form luminescent nanostructure suspensions in hexane (Figure 5) [137]. It was posited that 65 features hollow vesicles, with vesicle fusion releasing curvature energy, leading to a thermodynamically more stable tubular structure. Such aggregation-induced