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

• AChE, while pyrazole scaffolds possess the ability to reduce the tau and β-amyloid dual aggregation. Benzofuran-pyrazole aldehydes were employed in the Ugi azide reaction to give the desired hybrids. From the screened compounds, 2a, 2b, 2c, 2d, 2e, and 2f demonstrated notable efficacy in regulating the

• cells containing the Nrf2/antioxidant response element (ARE). The melatonin–lipoic acid (LA) hybrids 3a and 3b emerged as potent antioxidants, successfully inducing the Nrf2 transcriptional pathway at concentrations of 10, 30, and 100 μM (Figure 5). Notably, these hybrids exhibited lower CD values (28.1

• new family of ferulic acid–tacrine hybrids (FATHs), using the Ugi reaction. FATHs were selected because tacrine is a well-known cholinesterase (ChE) inhibitor, although it is hepatotoxic, and ferulic acid is a potent antioxidant. Fourteen FATH were synthesized and tested for hepatotoxicity

Synthesis of the 1,5-disubstituted tetrazole-methanesulfonylindole hybrid system via high-order multicomponent reaction

• Cesia M. Aguilar-Morales,
• América A. Frías-López,
• Nadia V. Emilio-Velázquez,
• Alejandro Islas-Jácome,
• Angelica Judith Granados-López,
• Jorge Gustavo Araujo-Huitrado,
• Yamilé López-Hernández,
• Hiram Hernández-López,
• Luis Chacón-García,
• Jesús Adrián López and
• Carlos J. Cortés-García

Beilstein J. Org. Chem. 2024, 20, 3077–3084, doi:10.3762/bjoc.20.256

• , 98160, México 10.3762/bjoc.20.256 Abstract A series of 1,5-disubstituted tetrazole-indole hybrids were synthesized via a high-order multicomponent reaction consisting of an Ugi-azide/Pd/Cu-catalyzed hetero-annulation cascade sequence. This operationally simple one-pot protocol allowed high bond-forming

• bioactivity study was proposed based on observations that indole-coumarin-thiadiazole hybrid compounds described by Kamath et al. [44], as well as indole-benzimidazole hybrids reported by Singla et al. [45] have shown potential as therapeutic agents for breast cancer treatment. Thereby, we hypothesized that

• with greater efficacy and selectivity against targets related to BC. Thus, the 1,5-disubstituted tetrazole-indole hybrids, presented different effects on cell proliferation inhibition in MCF-7 cells (Figure 1) that could be attributable to the molecular background of cells [46][47][48][49]. The

5th International Symposium on Synthesis and Catalysis (ISySyCat2023)

• Anthony J. Burke and
• Elisabete P. Carreiro

Beilstein J. Org. Chem. 2024, 20, 2704–2707, doi:10.3762/bjoc.20.227

• a new family of isatin-based α-acetamide carboxamide oxindole hybrids using the versatile Ugi four-component reaction [18]. Sixteen hybrids were prepared by reacting 5-amino-1-benzyl-3,3-dimethoxyindolin-2-one, benzyl isocyanide, carboxylic acids, and aldehyde/ketone derivatives, catalyzed by ZnF2

• in MeOH at room temperature with a short reaction time. Some of them were further functionalized with a 1,2,3-triazole ring via copper-catalyzed azide–alkyne cycloaddition (CuAAC) and deprotected with trifluoroacetic acid. Several hybrids were evaluated against six cancer cell lines, displaying GI50

Synthesis, electrochemical properties, and antioxidant activity of sterically hindered catechols with 1,3,4-oxadiazole, 1,2,4-triazole, thiazole or pyridine fragments

• Daria A. Burmistrova,
• Andrey Galustyan,
• Nadezhda P. Pomortseva,
• Kristina D. Pashaeva,
• Maxim V. Arsenyev,
• Oleg P. Demidov,
• Mikhail A. Kiskin,
• Andrey I. Poddel’sky,
• Nadezhda T. Berberova and
• Ivan V. Smolyaninov

Beilstein J. Org. Chem. 2024, 20, 2378–2391, doi:10.3762/bjoc.20.202

• activity against the HeLa cancer cell line [22]. 1,2,4-Triazole thioglycoside derivatives have antiviral activity against influenza strains H3N2 and H5N1 [31][32]. The 1,2,4-triazole-3-thione-imidazole hybrids displayed potential antibacterial activity against E. coli, S. aureus [33]. Heterocyclic thione

The Groebke–Blackburn–Bienaymé reaction in its maturity: innovation and improvements since its 21st birthday (2019–2023)

• Cristina Martini,
• Muhammad Idham Darussalam Mardjan and
• Andrea Basso

Beilstein J. Org. Chem. 2024, 20, 1839–1879, doi:10.3762/bjoc.20.162

• Ganesher [57] reported the one-pot cascade synthesis of indole-imidazo[1,2,a]pyridine hybrids 61 (Scheme 23). In this study, the convertible isocyanide 1-isocyano-2-(2,2-dimethoxyethyl)benzene (59, Kobayashi–Wessjohann isocyanide) was utilized as one of the precursors in the GBB reaction. The acetal

Syntheses and medicinal chemistry of spiro heterocyclic steroids

• Laura L. Romero-Hernández,
• Ana Isabel Ahuja-Casarín,
• Penélope Merino-Montiel,
• Sara Montiel-Smith,
• José Luis Vega-Báez and
• Jesús Sandoval-Ramírez

Beilstein J. Org. Chem. 2024, 20, 1713–1745, doi:10.3762/bjoc.20.152

• is compelling evidence that incorporating a heterocyclic moiety into a steroid can alter its pharmacological and pharmacokinetic properties, driving intense interest in the synthesis of such hybrids among research groups. In this review, we present an overview of recent synthetic methodologies

Synthesis of substituted triazole–pyrazole hybrids using triazenylpyrazole precursors

• Simone Gräßle,
• Laura Holzhauer,
• Nicolai Wippert,
• Olaf Fuhr,
• Martin Nieger,
• Nicole Jung and
• Stefan Bräse

Beilstein J. Org. Chem. 2024, 20, 1396–1404, doi:10.3762/bjoc.20.121

• of Technology, Kaiserstraße 12, 76131 Karlsruhe, Germany 10.3762/bjoc.20.121 Abstract A synthesis route to access triazole–pyrazole hybrids via triazenylpyrazoles was developed. Contrary to existing methods, this route allows the facile N-functionalization of the pyrazole before the attachment of

• the triazole unit via a copper-catalyzed azide–alkyne cycloaddition. The developed methodology was used to synthesize a library of over fifty new multi-substituted pyrazole–triazole hybrids. We also demonstrate a one-pot strategy that renders the isolation of potentially hazardous azides obsolete. In

• strategies to explore access to triazole–pyrazole hybrids. Triazole–pyrazole hybrids, particularly non-fused heterocycles of this class, have not been investigated systematically. Selected known derivatives (Figure 1, 1–4) inhibit the serine-threonine kinase ERK3 [12] or the cholera-causing bacterium Vibrio

The Ugi4CR as effective tool to access promising anticancer isatin-based α-acetamide carboxamide oxindole hybrids

• Carolina S. Marques,
• Aday González-Bakker and
• José M. Padrón

Beilstein J. Org. Chem. 2024, 20, 1213–1220, doi:10.3762/bjoc.20.104

• , we highlight the reputation of this reaction approach to access number and scaffold diversity of a library of isatin-based α-acetamide carboxamide oxindole hybrids, promising anticancer agents, in a mild and fast sustainable reaction process. The library was tested against six human solid tumor cell

• [8][9]. In the last few years we have been active in isatin modification using new synthetic approaches, anticipating the creation of new libraries of small-molecule hybrids with potential as cholinesterase inhibitors [10][11][12][13], important to treat neurodegenerative diseases, and anticancer

• -acetamide carboxamide oxindole hybrids 5 was obtained in moderate yields (26–63%), at room temperature, in short time (2 hours), proving the efficiency and the generality of this methodology. Aliphatic (2a, 2c and 2m), aromatic (2d, 2f, 2g, 2k and 2l), heterocyclic (2e, 2h, 2i, 2n and 2o), alkyne 2b and

Chemoenzymatic synthesis of macrocyclic peptides and polyketides via thioesterase-catalyzed macrocyclization

• Senze Qiao,
• Zhongyu Cheng and
• Fuzhuo Li

Beilstein J. Org. Chem. 2024, 20, 721–733, doi:10.3762/bjoc.20.66

• , and their hybrids, thioesterase (TE) domains play a significant role in late-stage macrocyclization. These domains can accept mimics of native substrates in vitro and exhibit potential for use in total synthesis. This review summarizes the recent advances of TE domains in the chemoenzymatic synthesis

• polyketides; thioesterase; Introduction Nonribosomal peptides, polyketides, and their hybrids exhibit significant diversity and a broad spectrum of bioactivities [1][2][3]. Particularly, macrocycles from these three categories of natural products are vital resources for developing pharmaceuticals and drug

• possible and provides a potential to construct the analogs library of these bioactive macrocycles for further biological investigations. This review presents representative examples of chemoenzymatic approaches for macrocyclic peptides, polyketides, and their hybrids employing TE domains, and particular

Production of non-natural 5-methylorsellinate-derived meroterpenoids in Aspergillus oryzae

• Jia Tang,
• Yixiang Zhang and
• Yudai Matsuda

Beilstein J. Org. Chem. 2024, 20, 638–644, doi:10.3762/bjoc.20.56

• a general understanding of their biosynthesis [7][8]. Polyketide–terpenoid hybrids are among the largest families of meroterpenoids. Orsellinic acid, an aromatic polyketide, and its analogues have been commonly identified as polyketide components in fungal meroterpenoids. Notably, 3,5

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

• version of antiSMASH 7.0 [25] software for the analysis of the Penicillium shentong XL-F41 genome, we identified 46 BGCs. These include 13 NRPS-like fragments, 6 NRPS, 13 type I PKS, 2 PKS/NRPS hybrids, 1 NI-siderophore, 2 NRP-metallophore/NRPS hybrids, 1 fungal RiPP with POP or UstH peptidase types, 1

• fungal-RiPP-like/T1PKS, 1 betalactone, 1 PKS type I/NRPS/indole hybrid, 1 fungal-RiPP-like/T1PKS hybrid, 1 NRP-metallophore/NRPS hybrid, NRPS-like/terpene/phosphonate hybrids, 3 terpenes, and 1 indole-related cluster (Table 5). BGC 7.3, identified as an indole-type gene cluster, includes genes for

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

• of hybrids of 1,2,3-triazole with other heterocycles and to identify biologically active compounds among the synthesized compounds. It is known that the cycloaddition reaction of azidopyrimidinediones with enamines [13] represents an effective method for the synthesis of pyrimidinyl amidines [14

Tying a knot between crown ethers and porphyrins

• Maksym Matviyishyn and
• Bartosz Szyszko

Beilstein J. Org. Chem. 2023, 19, 1630–1650, doi:10.3762/bjoc.19.120

• Maksym Matviyishyn Bartosz Szyszko Faculty of Chemistry, University of Wrocław, 14 F. Joliot-Curie St., 50-383 Wrocław, Poland 10.3762/bjoc.19.120 Abstract Porphyrins and crown ether hybrids have emerged as a promising class of molecules composed of elements of a tetrapyrrole macrocycle and an

• metals. In this perspective article, the overview of both the early designs of porphyrin-crown ether hybrids, as well as the most recent advances in the synthesis and characterisation of this remarkable group of macrocyclic systems, are addressed. The discussion covers the strategies employed in

• synthesising these systems, including cyclisation reactions, self-assembly, and their remarkable reactivity. The potential applications of porphyrin-crown ether hybrids are also highlighted. Moreover, the discussion identifies the challenges associated with synthesising and characterising hybrids, outlining

Pyridine C(sp²)–H bond functionalization under transition-metal and rare earth metal catalysis

• Haritha Sindhe,
• Malladi Mounika Reddy,
• Karthikeyan Rajkumar,
• Akshay Kamble,
• Amardeep Singh,
• Anand Kumar and
• Satyasheel Sharma

Beilstein J. Org. Chem. 2023, 19, 820–863, doi:10.3762/bjoc.19.62

• of the alkene provides the seven-membered cyclic intermediate 203. Subsequent reductive elimination furnishes the endo-annulated product 194 (Scheme 37b). Out of various pyridine-fused heterocyclic hybrids, azaindolines are important scaffolds in natural products and pharmaceuticals serving different

Facile access to 3-sulfonylquinolines via Knoevenagel condensation/aza-Wittig reaction cascade involving ortho-azidobenzaldehydes and β-ketosulfonamides and sulfones

• Ksenia Malkova,
• Andrey Bubyrev,
• Stanislav Kalinin and
• Dmitry Dar’in

Beilstein J. Org. Chem. 2023, 19, 800–807, doi:10.3762/bjoc.19.60

• structures developed recently, and, significantly, quinoline-3-sulfonamides are frequently encountered among such pharmacologically active hybrids (Figure 1b) [31][32][33][34]. Despite these facts, the diversity of quinoline-3-sulfonamides reported in the literature is limited due to obstacles in the

Synthesis of imidazo[1,2-a]pyridine-containing peptidomimetics by tandem of Groebke–Blackburn–Bienaymé and Ugi reactions

• Oleksandr V. Kolomiiets,
• Alexander V. Tsygankov,
• Maryna N. Kornet,
• Aleksander A. Brazhko,
• Vladimir I. Musatov and
• Valentyn A. Chebanov

Beilstein J. Org. Chem. 2023, 19, 727–735, doi:10.3762/bjoc.19.53

• the MCR repertoire. Therefore, an urgent problem is to synthesize structurally complex compounds, molecular hybrids containing pharmacophoric and peptidomimetic fragments, to explore their biological activity. The possibility of inserting an unsubstituted imidazo[1,2-a]pyridine fragment into the

• 7a–t in 28–72% yield (Scheme 4, Table 1). Having obtained several new compounds containing substituted imidazo[1,2-a]pyridine and peptidomimetic fragments linked by a CH2O linker, we further explored the possibility of synthesizing similar hybrids without a CH2O linker between the two moieties. The

CuAAC-inspired synthesis of 1,2,3-triazole-bridged porphyrin conjugates: an overview

• Dileep Kumar Singh

Beilstein J. Org. Chem. 2023, 19, 349–379, doi:10.3762/bjoc.19.29

• of the synthesis and properties of various porphyrin-triazole hybrids, this review will discuss some of the key reactions involved in the preparation of triazole-linked porphyrin conjugates. Keywords: azide–alkyne; click chemistry; CuAAC; 1,3-dipolar cycloaddition; porphyrin; 1,2,3-triazole

• medicinal chemistry. Owing to the strong absorption in the visible region, these 18π-electron systems also demonstrate excellent photoluminescence properties. Therefore, porphyrin hybrids have been widely used as efficient sensitizers for PDT applications and dye-sensitized solar cells (DSSCs). Because the

• majority of porphyrin hybrids are synthesized by modifying β- and meso-positions of porphyrin, thus numerous chromophoric groups and biologically important scaffolds have been attached to porphyrins at these positions in recent years. In the past, many synthetic procedures have been utilized to covalently

Navigating and expanding the roadmap of natural product genome mining tools

• Friederike Biermann,
• Sebastian L. Wenski and
• Eric J. N. Helfrich

Beilstein J. Org. Chem. 2022, 18, 1656–1671, doi:10.3762/bjoc.18.178

• ). Moreover, since these assembly line-like pathways follow the same biosynthetic principle, they often form hybrids with other biosynthetic assembly line-like pathways [21]. Prominent examples of the usage of pHMMs are the original algorithm of the antibiotics & Secondary Metabolite Analysis Shell (antiSMASH

On drug discovery against infectious diseases and academic medicinal chemistry contributions

• Yves L. Janin

Beilstein J. Org. Chem. 2022, 18, 1355–1378, doi:10.3762/bjoc.18.141

• pharmacological data already available for this class of inhibitors such as compounds 63–65 [115][315]. Indeed, out of the structure–activity relationship of the many series of inhibitors of the ATP-ase function of type IIA topoisomerases discovered, it seems plausible to design and synthesize hybrids, combining

Morita–Baylis–Hillman reaction of 3-formyl-9H-pyrido[3,4-b]indoles and fluorescence studies of the products

• Nisha Devi and
• Virender Singh

Beilstein J. Org. Chem. 2022, 18, 926–934, doi:10.3762/bjoc.18.92

• family and is associated with a broad spectrum of biological properties. 3-Formyl-9H-pyrido[3,4-b]indole is a such potent precursor belonging to this family which can be tailored for installing diversity at various positions of β-carboline to generate unique molecular hybrids of biological importance

• group has also investigated the scope of 1-formyl-β-carbolines for generating unique molecular hybrids by application of the Morita–Baylis–Hillman reaction [48][49][50]. It was also revealed from a detailed literature survey that only limited reports have been documented toward exploration of 3-formyl

Progress and challenges in the synthesis of sequence controlled polysaccharides

• Giulio Fittolani,
• Theodore Tyrikos-Ergas,
• Denisa Vargová,
• Manishkumar A. Chaube and
• Martina Delbianco

Beilstein J. Org. Chem. 2021, 17, 1981–2025, doi:10.3762/bjoc.17.129

• observed for cellulose [67][79], while the multifluorinated compound formed considerably shorter platelets. Cellulose–xylan [80] and cellulose–chitin [81] hybrids were also obtained upon enzymatic polymerization of the respective dimers. An amino or azido functionality in the C-6 position allows for

• amylose with narrow MW distribution, amylose hybrids, and amylose-functionalized materials [186]. Linear and branched oligosaccharides with mixed α(1–3) and α(1–4) linkages were synthesized using a glucansucrase from Lactobacillus reuteri [187][188]. Even though several chemical methods are available for

Asymmetric organocatalyzed synthesis of coumarin derivatives

• Natália M. Moreira,
• Lorena S. R. Martelli and
• Arlene G. Corrêa

Beilstein J. Org. Chem. 2021, 17, 1952–1980, doi:10.3762/bjoc.17.128

• multicomponent reaction (IMCR) [31]. The enantioenriched hemiacetals 5 were obtained using the Jørgensen catalyst 7 as previously described by Rueping et al. [32]. This approach enables the rapid assembly of complex natural product hybrids 6 including up to four different molecular fragments, such as

Double-headed nucleosides: Synthesis and applications

• Vineet Verma,
• Jyotirmoy Maity,
• Vipin K. Maikhuri,
• Ritika Sharma,
• Himal K. Ganguly and
• Ashok K. Prasad

Beilstein J. Org. Chem. 2021, 17, 1392–1439, doi:10.3762/bjoc.17.98

• double-headed nucleosides 4a,b were dimethoxytritylated (DMTr), phosphitylated, and incorporated into DNA oligonucleotides using the standard automated phosphoramidite method. The UV-based melting temperature (Tm) of hybrids of the modified oligonucleotides with complementary DNA strands were studied

• nucleoside 37 (Scheme 9) [34]. The double-headed nucleoside 37 was dimethoxytritylated, phosphitylated, and incorporated into 11- to 13-mer oligonucleotides using the standard automated phosphoramidite method. The UV-based melting temperature (Tm) of hybrids of the modified oligonucleotides with

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

• (GraphPad Software, CA). Components of the LNPs. A) Lipid species and lipidated cell-penetrating peptides applied by postinsertion. B) Graphical representation of aptamer–probe hybrids. LNPs with T7 pass through the transwell cell barrier and are taken up by target cells. HeLa (CCR5-negative control cell

[2 + 1] Cycloaddition reactions of fullerene C₆₀ based on diazo compounds

• Yuliya N. Biglova

Beilstein J. Org. Chem. 2021, 17, 630–670, doi:10.3762/bjoc.17.55

• fullerene array 213. The synthetic route to conjugates 214 of fullerene with benzothiadiazole. The synthetic route to conjugates 215 of fullerene with diketopyrrolopyrrole. The synthetic route to fullerene–acetylene hybrids. [60]PCBM derivatives containing various aromatic and alkyl groups bound to the C60