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

• only for most of unhindered small ones), their partial instability and their potential toxicity [27], thus in situ generation represents a sustainable alternative for their conventional use and this issue has been recently reviewed by Baht and Heravi [28]. In situ generation of isocyanides has been

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

• synthesized compounds were evaluated for their DNA binding properties and screened for cytotoxicity against leukemia cancer cells (Jurkat), demonstrating IC50 values in the micromolar range (14.2 to 36.5 µM). Importantly, these derivatives exhibited minimal toxicity toward normal cells (PBMCs). Furthermore

Polymer degrading marine Microbulbifer bacteria: an un(der)utilized source of chemical and biocatalytic novelty

• Weimao Zhong and
• Vinayak Agarwal

Beilstein J. Org. Chem. 2024, 20, 1635–1651, doi:10.3762/bjoc.20.146

• , other parabens were not detected. Parabens are used as preservatives in pharmaceutical, food, and cosmetic industries due to their low toxicity, stability, and activity against a broad spectrum of microorganisms [124]. Industrially, parabens are prepared starting from 4HBA, which in turn, is a

Divergent role of PIDA and PIFA in the AlX₃ (X = Cl, Br) halogenation of 2-naphthol: a mechanistic study

• Kevin A. Juárez-Ornelas,
• Manuel Solís-Hernández,
• Pedro Navarro-Santos,
• J. Oscar C. Jiménez-Halla and
• César R. Solorio-Alvarado

Beilstein J. Org. Chem. 2024, 20, 1580–1589, doi:10.3762/bjoc.20.141

• halogenation via PhIX2. Keywords: aromatic bromination; aromatic chlorination; density functional theory (DFT); hypervalent iodine; iodine(III); Introduction Hypervalent iodine(III) reagents have gained attention as strong oxidants with a low toxicity [1][2][3][4][5][6][7][8] and due to the ability to mimic

Photoswitchable glycoligands targeting Pseudomonas aeruginosa LecA

• Yu Fan,
• Ahmed El Rhaz,
• Stéphane Maisonneuve,
• Emilie Gillon,
• Maha Fatthalla,
• Franck Le Bideau,
• Guillaume Laurent,
• Samir Messaoudi,
• Anne Imberty and
• Juan Xie

Beilstein J. Org. Chem. 2024, 20, 1486–1496, doi:10.3762/bjoc.20.132

• /off or from low to high. This strategy can be used for specific targeting or local drug activation to reduce its toxicity [14]. There is an increasing use of the photoisomerization to control the conformation as well as the activities of various biomolecules with the development of photopharmacology

Hypervalent iodine-catalyzed amide and alkene coupling enabled by lithium salt activation

• Akanksha Chhikara,
• Fan Wu,
• Navdeep Kaur,
• Prabagar Baskaran,
• Alex M. Nguyen,
• Zhichang Yin,
• Anthony H. Pham and
• Wei Li

Beilstein J. Org. Chem. 2024, 20, 1405–1411, doi:10.3762/bjoc.20.122

• development of chiral hypervalent iodines by Wirth, Kita, Ishihara, Muñiz, and many others, have firmly established these reagents as useful catalysts for a wide variety of chemical transformations [6][7][8][9][10][11][12][13][14][15][16][17]. A number of features, including low toxicity, high stability, ease

Transition-metal-catalyst-free electroreductive alkene hydroarylation with aryl halides under visible-light irradiation

• Kosuke Yamamoto,
• Kazuhisa Arita,
• Masami Kuriyama and
• Osamu Onomura

Beilstein J. Org. Chem. 2024, 20, 1327–1333, doi:10.3762/bjoc.20.116

• chemical reagents; however, these methods have some drawbacks, such as reagent toxicity/stability and limited substrate scope [12][13][14]. While recent advances in photochemistry have remarkably expanded the synthetic utility of (hetero)aryl radicals in organic synthesis [15][16][17][18][19][20], visible

Oxidative hydrolysis of aliphatic bromoalkenes: scope study and reactivity insights

• Amol P. Jadhav and
• Claude Y. Legault

Beilstein J. Org. Chem. 2024, 20, 1286–1291, doi:10.3762/bjoc.20.111

• metals, inspired by Nature's metalloproteins. However, using toxic and expensive metals is not always practical, making alternative oxidative methodologies more appealing. Enter hypervalent iodine reagents – a leading metal-free choice for oxidation reactions. These robust and low-toxicity reagents have

Light on the sustainable preparation of aryl-cored dibromides

• Fabrizio Roncaglia,
• Alberto Ughetti,
• Nicola Porcelli,
• Biagio Anderlini,
• Andrea Severini and
• Luca Rigamonti

Beilstein J. Org. Chem. 2024, 20, 1076–1087, doi:10.3762/bjoc.20.95

• context of covalent organic frameworks (COFs) and metal-organic frameworks (MOFs), frequently assembled through imine linkages. While C–H activation through halogens presents clear technical advantages, it also brings forth concerns about the toxicity of halo compounds to both human health and the

• ) greater electrophilicity of the halo compound due to better leaving group ability of the halide ion, (iii) reduced toxicity, presumably due to faster hydrolysis [18], and (iv) easier oxidation of the halide to molecular halogen (E0 = 1.087 V (SHE) for Br2/Br−; E0 = 1.358 V (SHE) for Cl2/Cl−) [19

Activity assays of NnlA homologs suggest the natural product N-nitroglycine is degraded by diverse bacteria

• Kara A. Strickland,
• Brenda Martinez Rodriguez,
• Ashley A. Holland,
• Shelby Wagner,
• Michelle Luna-Alva,
• David E. Graham and
• Jonathan D. Caranto

Beilstein J. Org. Chem. 2024, 20, 830–840, doi:10.3762/bjoc.20.75

• hexahydro-1,3,5-trinitro-1,3,5-triazine (commonly called RDX), octogen (HMX), and hexanitrohexaazaisowurtzitane (CL-20) are compounds found in military grade explosives and propellants. Contamination of these cyclic nitramines in soil and groundwater is concerning due to their toxicity and potential

• producers and of NNG is unknown. Additionally, NNG’s physiological function is unknown, but it is toxic to plants, mice, and Gram-negative bacteria [25][26]. While there is no direct evidence of the mechanism of this toxicity, NNG has been shown to competitively inhibit succinate dehydrogenase, a component

• noursei, an NNG-producing bacterium, did not reveal any NnlA homologs. Interestingly, four NMOs are annotated in the S. noursei genome. These enzymes could protect S. noursei from NNG toxicity during its biosynthesis. Meanwhile, we posit that NnlA protects non-NNG producing bacteria from exposure. In vivo

Synthesis of new representatives of A₃B-type carboranylporphyrins based on meso-tetra(pentafluorophenyl)porphyrin transformations

• Victoria M. Alpatova,
• Evgeny G. Rys,
• Elena G. Kononova and
• Valentina A. Ol'shevskaya

Beilstein J. Org. Chem. 2024, 20, 767–776, doi:10.3762/bjoc.20.70

• [8]. Further improvement of the PDT method requires the search for new photosensitizers having higher photoactivity, tumor selectivity, and high singlet oxygen quantum yield, as well as low in vivo toxicity [7]. Therefore, some strategies have been developed to enhance the therapeutic efficiency of

• biomacromolecule [10][11]. In this context, fluorinated porphyrins have attracted considerable interest due to their biological properties such as low toxicity, metabolic stability, and cellular uptake. The introduction of a fluorine atom into the molecule is the feasibility to change drastically its biological

• meso-pentafluorophenyl-substituted porphyrins. Carboranes, due to their unique physical and chemical properties such as high chemical and biological stability [28][29], three-dimensional aromaticity [30][31], low toxicity [28], high hydrophobicity, and enriched boron content [32][33] are perspective

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

• relationship (SAR) studies on selective inhibitors reduce the prevalence of undesired effects, such as toxicity in mammals [4]. Despite being employed in the field for over three decades, the mode of action of preemergence herbicide cinmethylin (1, Scheme 1) has remained unknown until 2018. At that time, the

Switchable molecular tweezers: design and applications

• Pablo Msellem,
• Maksym Dekthiarenko,
• Nihal Hadj Seyd and
• Guillaume Vives

Beilstein J. Org. Chem. 2024, 20, 504–539, doi:10.3762/bjoc.20.45

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

• related environments [8]. The mechanism of action involves the binding of BIMs to the penicillin-restricting protein PBP2a which inhibits the biosynthesis of the bacterial cell wall, making the treatment feasible without any toxicity to human cells [9][10]. The applications of BIMs have also been extended

• counterparts, due to their recyclability, ease of handling, and low cost [40]. Carbon-based solid acid catalysts especially are an interesting catalyst class, because they display low corrosiveness, toxicity, and higher catalytic activity, while also being insoluble in most organic solvents. The large amount

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

• embryonic cells. Identification of the cause of the registered selective toxicity of the tested compounds requires further study. Conclusion Thus, we have introduced an effective base-catalyzed tandem reaction including a Cornforth-type rearrangement of 1-heteroaryl-1,2,3-triazole-4-carboximidamides and

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

• 1881, Kucherov identified mercury(II) salts in sulfuric acid as efficient promoters of the hydration of alkynes and this catalyst system has found applications in industrial scale synthesis [10]. However, the toxicity and the environmental issues associated with the use of mercury-based compounds have

• ][52][53][54]. However, some of these procedures suffer from major drawbacks, such as the toxicity and/or high cost of the metal catalysts, the need to use concentrated Brønsted acids in high excess, long reaction times, and high temperatures. In addition, these reactions have been studied mainly in

Recent advancements in iodide/phosphine-mediated photoredox radical reactions

• Tinglan Liu,
• Yu Zhou,
• Junhong Tang and
• Chengming Wang

Beilstein J. Org. Chem. 2023, 19, 1785–1803, doi:10.3762/bjoc.19.131

• radical reactions. These reactions have garnered much attention due to their cost-effectiveness, low toxicity, and widespread availability. Notably, the NaI/PPh3 combined system has been successfully employed in the photofixation of nitrogen [51]. Despite these remarkable progresses made, there remain

Effects of the aldehyde-derived ring substituent on the properties of two new bioinspired trimethoxybenzoylhydrazones: methyl vs nitro groups

• Dayanne Martins,
• Roberta Lamosa,
• Talis Uelisson da Silva,
• Carolina B. P. Ligiero,
• Sérgio de Paula Machado,
• Daphne S. Cukierman and
• Nicolás A. Rey

Beilstein J. Org. Chem. 2023, 19, 1713–1727, doi:10.3762/bjoc.19.125

• ]. The study also found that those coordination compounds were selective towards abnormal cells, exhibiting lower toxicity for healthy human hepatocytes. On the other hand, an important development in cancer research is the use of physiological metal ion complexes, which afford more biocompatibility and

• ions. For this reason, we feel quite comfortable to state that these compounds are promising, and deserve deeper studies regarding their interactions with, for example, aluminum(III) and cell toxicity assessments. Experimental All solvents and reagents were purchased from commercial suppliers Sigma

A series of perylene diimide cathode interlayer materials for green solvent processing in conventional organic photovoltaics

• Kathryn M. Wolfe,
• Shahidul Alam,
• Eva German,
• Fahad N. Alduayji,
• Maryam Alqurashi,
• Frédéric Laquai and
• Gregory C. Welch

Beilstein J. Org. Chem. 2023, 19, 1620–1629, doi:10.3762/bjoc.19.119

• considered green, where a green solvent can be described as one that exhibits little to no toxicity to humans or animals, and has a minimal environmental impact when considering life-cycle assessments [21]. In terms of the electrochemical properties of the series, it was hypothesized that the addition of a

• are coated onto of the BHJ in this case [19]. Furthermore, ethyl acetate is considered a green solvent due to its low toxicity and minimal associated hazards [20][22][29]. We note that each compound has minimal solubility in methanol, the most common processing solvent for CILs, and instead encourage

Secondary metabolites of Diaporthe cameroonensis, isolated from the Cameroonian medicinal plant Trema guineensis

• Bel Youssouf G. Mountessou,
• Élodie Gisèle M. Anoumedem,
• Blondelle M. Kemkuignou,
• Yasmina Marin-Felix,
• Frank Surup,
• Marc Stadler and
• Simeon F. Kouam

Beilstein J. Org. Chem. 2023, 19, 1555–1561, doi:10.3762/bjoc.19.112

• cereals [31]. The isolation of the alternariol compound in this study is not surprising because it has been reported that dibenzo-α-pyrones are also found in mycobionts, plants, some animal dung, and endophytes [32][33]. Although the toxicity of dibenzo-α-pyrones is not fully understood and varies amongst

Synthesis of ether lipids: natural compounds and analogues

• Marco Antônio G. B. Gomes,
• Alicia Bauduin,
• Chloé Le Roux,
• Romain Fouinneteau,
• Wilfried Berthe,
• Mathieu Berchel,
• Hélène Couthon and
• Paul-Alain Jaffrès

Beilstein J. Org. Chem. 2023, 19, 1299–1369, doi:10.3762/bjoc.19.96

• has similar cell toxicity than edelfosine-C18 on HL-60 leukemic cells [129][130]. The authors also reported that the sulfone 26.5 (Figure 26B) had similar cytotoxicity than edelfosine-C18. In 1987, the group of E. J. Modest reported that the thioether 26.4 featured comparable cytotoxicity than C18

Non-noble metal-catalyzed cross-dehydrogenation coupling (CDC) involving ether α-C(sp³)–H to construct C–C bonds

• Hui Yu and
• Feng Xu

Beilstein J. Org. Chem. 2023, 19, 1259–1288, doi:10.3762/bjoc.19.94

• , and the cleavage of the C(sp3)–H bond in the ether substrates which produces α-alkyl radicals is the rate-determining step. Fe-catalyzed reactions Iron is a transition metal with abundant reserves, low price, and non-toxicity, which shows many characteristics in catalytic processes, such as the

Unravelling a trichloroacetic acid-catalyzed cascade access to benzo[f]chromeno[2,3-h]quinoxalinoporphyrins

• Chandra Sekhar Tekuri,
• Pargat Singh and
• Mahendra Nath

Beilstein J. Org. Chem. 2023, 19, 1216–1224, doi:10.3762/bjoc.19.89

• visible and near IR regions [11][12][13][14]. Similarly, simple quinoxaline-based heterocycles have shown their potential as photosensitizers to induce toxicity in a single cell green algae such as Chlamydomonas reinhardtii [15] and also displayed efficacy against Mycobacterium tuberculosis and other

Photoredox catalysis harvesting multiple photon or electrochemical energies

• Mattia Lepori,
• Simon Schmid and
• Joshua P. Barham

Beilstein J. Org. Chem. 2023, 19, 1055–1145, doi:10.3762/bjoc.19.81

Clauson–Kaas pyrrole synthesis using diverse catalysts: a transition from conventional to greener approach

• Dileep Kumar Singh and
• Rajesh Kumar

Beilstein J. Org. Chem. 2023, 19, 928–955, doi:10.3762/bjoc.19.71

• presence of 4 mol % ZrOCl2∙8H2O as a catalyst in water at 60 °C (Scheme 11a). Among many catalysts used for the synthesis of N-substituted pyrroles, Zr(IV) compounds, especially ZrOCl2∙8H2O have received more attention because of its high coordination ability, low toxicity, low cost and high activity. In