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

• and γ-secretase, it produces Aβ-42. This form misfolds, leading to the formation of insoluble protein aggregates known as senile plaques, causing toxicity [28][29]. Oxidative stress occurs when there is an imbalance between prooxidants and antioxidants in the body, leading to damage in various

• -directed and metabolic antioxidants have shown efficacy in AD mouse models, with ongoing trials for vitamin E and selenium [32]. Ugi reaction: As already mentioned, one of the main targets in AD treatment are cholinesterase ligands. In recent years, butyrylcholinesterase, an enzyme present in high

• demonstrating the highest potential among the tested compounds against acetylcholinesterase. Furthermore, Pachón-Angona et al. [35] synthesized hybrid molecules using the Ugi reaction (Scheme 3), with antioxidant compounds as starting substrates, pursuing the aim of developing more powerful antioxidants. The

N-Glycosides of indigo, indirubin, and isoindigo: blue, red, and yellow sugars and their cancerostatic activity

• Peter Langer

Beilstein J. Org. Chem. 2024, 20, 2840–2869, doi:10.3762/bjoc.20.240

• . The most important biomolecular step, however, was the early production (already after one hour) of reactive oxygen species (ROS). This was demonstrated by pretreatment with antioxidants which completely stopped induction of apoptosis and of the loss of cell viability and resulted in disappearance of

• worth to be noted that all these activation steps were stopped by the presence of antioxidants which indicates that ROS act as key regulators of the antitumor effects of 3-alkylideneoxindole-N-glycosides 48. In the last decades, we have witnessed an increasing incidence of cutaneous T-cell lymphoma

Efficient modification of peroxydisulfate oxidation reactions of nitrogen-containing heterocycles 6-methyluracil and pyridine

• Alfiya R. Gimadieva,
• Yuliya Z. Khazimullina,
• Aigiza A. Gilimkhanova and
• Akhat G. Mustafin

Beilstein J. Org. Chem. 2024, 20, 2599–2607, doi:10.3762/bjoc.20.219

• useful. 5-Hydroxy-6-methyluracil (HMU) (Figure 1a) and 5-hydroxy-1,3,6-trimethyluracil (HTMU) (Figure 1b) have been identified as effective antioxidants and radical traps [5][6][7]. Additionally, 2-hydroxypyridine (HPy) has significant synthetic potential in the design of various bioactive compounds

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

• most effective antioxidants in the lipid peroxidation reaction. Conclusion Thus, we have synthesized a series of new sterically hindered catechols with thioether or thione groups containing various heterocyclic fragments with good yields of 42–80%. The interaction of 3,5-di-tert-butyl-o-benzoquinone

• . Thus, in most of the studied assays, compounds 3 and 4 with a 4-phenylthiazole moiety turned out to be effective antioxidants among catechol thioethers, and 8 and 9 among thiones with a catechol fragment, which is consistent with electrochemical data. The X-ray structure of catechol 5 (the thermal

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

• , and epileptic disorders [26][27]. Four mechanisms have been reported for the treatment of Alzheimer's disease with crocins. Crocins function as antioxidants that slow down the progression of the disease by increasing the ʟ-glutathione (GSH) level and reducing the presence of reactive oxygen species

Discrimination of β-cyclodextrin/hazelnut (Corylus avellana L.) oil/flavonoid glycoside and flavonolignan ternary complexes by Fourier-transform infrared spectroscopy coupled with principal component analysis

• Nicoleta G. Hădărugă,
• Gabriela Popescu,
• Dina Gligor (Pane),
• Cristina L. Mitroi,
• Sorin M. Stanciu and
• Daniel Ioan Hădărugă

Beilstein J. Org. Chem. 2023, 19, 380–398, doi:10.3762/bjoc.19.30

• solubility and bioaccessibility of the hazelnut oil components and antioxidants can be increased, as well as the controlled release of bioactive compounds (fatty acid glycerides and antioxidant flavonoids, namely hesperidin, naringin, rutin, and silymarin). The appropriate method for obtaining the ternary

• of oils and fats is the addition of antioxidants. Among food grade antioxidants, natural polyphenols such as flavonoids and flavonoid-based extracts are widely used [35][36][37][38][39][40][41]. Generally, flavonoids have a high number of phenolic hydroxy groups that provide the antioxidant activity

• -cyclodextrin hydrate (red), C. avellana oil (pink), and hesperidin (green). PC2 versus PC1 scores plot from the FTIR–PCA analysis of the flavonoid glycoside and flavonolignan antioxidants (codes: “H” – hesperidin, “N” – naringin, “R” – rutin and “S” – silymarin); only wavenumbers of the FTIR bands were used as

An efficient metal-free and catalyst-free C–S/C–O bond-formation strategy: synthesis of pyrazole-conjugated thioamides and amides

• Shubham Sharma,
• Dharmender Singh,
• Sunit Kumar,
• Vaishali,
• Rahul Jamra,
• Naveen Banyal,
• Deepika,
• Chandi C. Malakar and
• Virender Singh

Beilstein J. Org. Chem. 2023, 19, 231–244, doi:10.3762/bjoc.19.22

• ], anticancer [13][14][15], antiviral [16], analgesic [17], antioxidants, antimicrobial [18], antidiabetic, anticonvulsant [19], antihelminthic [20], and antiarrhythmic activities. The pyrazole nucleus is a core unit in several FDA-approved marketed drugs such as sildenafil [21][22][23], celebrex [24][25

Inline purification in continuous flow synthesis – opportunities and challenges

• Jorge García-Lacuna and
• Marcus Baumann

Beilstein J. Org. Chem. 2022, 18, 1720–1740, doi:10.3762/bjoc.18.182

• extraction of antioxidants from olive leaf waste [130], and of patchoulol from green algal cells [49]. In the last case, nanofiltration is coupled to an inline phase separation to both concentrate the compound and reuse the solvent. In another scenario, a two-stage membrane cascade was used as a purification

Synthetic strategies for the preparation of γ-phostams: 1,2-azaphospholidine 2-oxides and 1,2-azaphospholine 2-oxides

• Jiaxi Xu

Beilstein J. Org. Chem. 2022, 18, 889–915, doi:10.3762/bjoc.18.90

• to the cyano group followed by hydrolysis to give the final product 223 (Scheme 36). The product 223 showed antitumor activity in a biological assay [20]. To develop antioxidants and antitumor agents, the same group synthesized chromene-fused 5-oxo-1,2-azaphospholidine 2-oxide derivatives. The

Synthesis of novel alkynyl imidazopyridinyl selenides: copper-catalyzed tandem selenation of selenium with 2-arylimidazo[1,2-a]pyridines and terminal alkynes

• Mio Matsumura,
• Kaho Tsukada,
• Kiwa Sugimoto,
• Yuki Murata and
• Shuji Yasuike

Beilstein J. Org. Chem. 2022, 18, 863–871, doi:10.3762/bjoc.18.87

• -alkynylselenides III exhibits a binding interaction between calf-thymus DNA and human serum albumin [13]. Moreover, imidazopyridine derivatives IV with selanyl groups, 3-aryl- or alkylselanylimidazo[1,2-a]pyridines, were reported to act as potential antioxidants and showed antiproliferative activity [14][15

Photophysical, photostability, and ROS generation properties of new trifluoromethylated quinoline-phenol Schiff bases

• Inaiá O. Rocha,
• Yuri G. Kappenberg,
• Wilian C. Rosa,
• Clarissa P. Frizzo,
• Nilo Zanatta,
• Marcos A. P. Martins,
• Isadora Tisoco,
• Bernardo A. Iglesias and
• Helio G. Bonacorso

Beilstein J. Org. Chem. 2021, 17, 2799–2811, doi:10.3762/bjoc.17.191

• complexes in OLEDs. Due to the ability to increase the electron transport and decrease molecule stacking, trifluoromethyl-substituted molecules have been employed to the development of phosphorescent materials [19][20][21]. On the other hand, antioxidants are known for protecting organisms against cell

Total synthesis of ent-pavettamine

• Memory Zimuwandeyi,
• Manuel A. Fernandes,
• Amanda L. Rousseau and
• Moira L. Bode

Beilstein J. Org. Chem. 2021, 17, 1440–1446, doi:10.3762/bjoc.17.99

• , connected by one or more unsubstituted methylene linkages, within their structure [2]. The interest in polyamines arises from the diverse roles and functions they play in biological systems [3][4]; for example, as stabilizers of RNA and DNA, secondary messengers, nutrients, antioxidants, growth factors, and

Stereoselective synthesis and transformation of pinane-based 2-amino-1,3-diols

• Ákos Bajtel,
• Mounir Raji,
• Matti Haukka,
• Ferenc Fülöp and
• Zsolt Szakonyi

Beilstein J. Org. Chem. 2021, 17, 983–990, doi:10.3762/bjoc.17.80

• enantioselective transformations, while the 2-phenyliminooxazolidines could be interesting in the field of antiproliferative or antioxidants studies based on our former studies on 2-imino-1,3-heterocycles [42][43]. Biologically active 2-amino-1,3-diols. NOESY experiments and X-ray structure elucidation of

Regioselective chemoenzymatic syntheses of ferulate conjugates as chromogenic substrates for feruloyl esterases

• Olga Gherbovet,
• Fernando Ferreira,
• Apolline Clément,
• Mélanie Ragon,
• Julien Durand,
• Sophie Bozonnet,
• Michael J. O'Donohue and
• Régis Fauré

Beilstein J. Org. Chem. 2021, 17, 325–333, doi:10.3762/bjoc.17.30

• polyhydroxylated molecules of interest (e.g., antioxidants) [4][26] and of novel chromogenic feruloylated substrates with various physicochemical features for screening applications. Accordingly, we observed that transesterifications only occurred when using primary benzylic alcohols; no phenol acylation was

4-Hydroxy-3-methyl-2(1H)-quinolone, originally discovered from a Brassicaceae plant, produced by a soil bacterium of the genus Burkholderia sp.: determination of a preferred tautomer and antioxidant activity

• Dandan Li,
• Naoya Oku,
• Yukiko Shinozaki,
• Yoichi Kurokawa and
• Yasuhiro Igarashi

Beilstein J. Org. Chem. 2020, 16, 1489–1494, doi:10.3762/bjoc.16.124

• immunity [33], among which redox enzymes and antioxidants are the direct countermeasures to neutralize the toxicity of ROS [34]. Limited examples of antioxidants include catecholamine melanin from a fungus Cryptococcus neoformans [35], 1,8-dihydroxynaphthalene melanin from fungi Wangiella dermatitidis and

Synthesis and anticancer activity of bis(2-arylimidazo[1,2-a]pyridin-3-yl) selenides and diselenides: the copper-catalyzed tandem C–H selenation of 2-arylimidazo[1,2-a]pyridine with selenium

• Mio Matsumura,
• Tsutomu Takahashi,
• Hikari Yamauchi,
• Shunsuke Sakuma,
• Yukako Hayashi,
• Tadashi Hyodo,
• Tohru Obata,
• Kentaro Yamaguchi,
• Yasuyuki Fujiwara and
• Shuji Yasuike

Beilstein J. Org. Chem. 2020, 16, 1075–1083, doi:10.3762/bjoc.16.94

• some reported to act as antioxidants and show activities that are medicinally relevant; hence, the development of efficient methods for their synthesis is an important objective. Herein, a simple method for the synthesis of selenides and diselenides bearing imidazo[1,2-a]pyridine rings and their

• potential antioxidants and showed antiproliferative activity [27][28]. Consequently, they have attracted much attention, and methods for their syntheses have been actively pursued. A powerful method for the synthesis of 3-selanylimidazo[1,2-a]pyridines involves the C–H selenation using imidazopyridine and a

Understanding the role of active site residues in CotB2 catalysis using a cluster model

• Keren Raz,
• Ronja Driller,
• Thomas Brück,
• Bernhard Loll and
• Dan T. Major

Beilstein J. Org. Chem. 2020, 16, 50–59, doi:10.3762/bjoc.16.7

• by featuring anticancer, antibacterial, anti-inflammatory, and antiretroviral activities [37]. Moreover, they are applied in the food industry as antioxidants and sweeteners [4]. CotB2 is a bacterial diterpene cyclase from S. melanosporofaciens, which catalyzes the formation of cyclooctat-9-en-7-ol

One-pot preparation of 4-aryl-3-bromocoumarins from 4-aryl-2-propynoic acids with diaryliodonium salts, TBAB, and Na₂S₂O₈

• Teppei Sasaki,
• Katsuhiko Moriyama and
• Hideo Togo

Beilstein J. Org. Chem. 2018, 14, 345–353, doi:10.3762/bjoc.14.22

• coumarins arises from the fact that the coumarin skeleton is present in many natural products extracted from plants [1][2][3] and some of them show potent pharmacological activities, such as antidepressant [4], antimicrobial [5][6], antioxidants [7][8], anti-inflammatory [9][10], antinociceptive [11

Vinylphosphonium and 2-aminovinylphosphonium salts – preparation and applications in organic synthesis

• Anna Kuźnik,
• Roman Mazurkiewicz and
• Beata Fryczkowska

Beilstein J. Org. Chem. 2017, 13, 2710–2738, doi:10.3762/bjoc.13.269

• anticancer drugs, antioxidants, or functional probes into the mitochondria [5][6][7][8]. Review 1. Synthesis of vinylphosphonium salts 1.1. Alkylation of phosphines with alkyl halides One of the most common methods for the preparation of vinylphosphonium salts 1 is the quaternization of vinylphosphines with

Opportunities and challenges for the sustainable production of structurally complex diterpenoids in recombinant microbial systems

• Katarina Kemper,
• Max Hirte,
• Markus Reinbold,
• Monika Fuchs and
• Thomas Brück

Beilstein J. Org. Chem. 2017, 13, 845–854, doi:10.3762/bjoc.13.85

• (precursor for pharmaceutic forskolin) or miltiradiene (precursor for antioxidants and tanshinones) may be within reach [66]. Additionally, genetic engineering of diterpene synthases enhances the knowledge of structure–function relationships alongside with increasing supply of novel potentially bioactive

Isoxazole derivatives as new nitric oxide elicitors in plants

• Anca Oancea,
• Emilian Georgescu,
• Florentina Georgescu,
• Alina Nicolescu,
• Elena Iulia Oprita,
• Catalina Tudora,
• Lucian Vladulescu,
• Marius-Constantin Vladulescu,
• Florin Oancea and
• Calin Deleanu

Beilstein J. Org. Chem. 2017, 13, 659–664, doi:10.3762/bjoc.13.65

• reactive oxygen species (ROS) production in plant tissues. Usually, NO and ROS, such as O2−, OH· and H2O2, together are required to induce the activation of various defense-related enzymes in plants [55]. Plant cells contain oxygen radical detoxifying enzymes and nonenzymatic antioxidants which have an

Selective synthesis of thioethers in the presence of a transition-metal-free solid Lewis acid

• Federica Santoro,
• Matteo Mariani,
• Federica Zaccheria,
• Rinaldo Psaro and
• Nicoletta Ravasio

Beilstein J. Org. Chem. 2016, 12, 2627–2635, doi:10.3762/bjoc.12.259

• antioxidants in polymers [6]. They are typically synthesized through the condensation of a thiol with organic halides under strong basic conditions [7][8][9], but due to the high toxicity of alkyl halides the introduction of new methods of access to this kind of materials is desirable. The ideal reaction from

Thermal and oxidative stability of Atlantic salmon oil (Salmo salar L.) and complexation with β-cyclodextrin

• Daniel I. Hădărugă,
• Mustafa Ünlüsayin,
• Alexandra T. Gruia,
• Cristina Birău (Mitroi),
• Gerlinde Rusu and
• Nicoleta G. Hădărugă

Beilstein J. Org. Chem. 2016, 12, 179–191, doi:10.3762/bjoc.12.20

• , aldehydic acids, alkanes and alkenes [17]. In the case of fish oil, the main odoriferous compounds resulting from oxidation are propanal, pent-1-en-3-one, hex-3-enal, and pent-1-en-3-ol [18][19][20]. The stabilization of fish oils can be simply performed by using antioxidants. Natural or synthetic

• antioxidants are often used. Among natural antioxidants, tocopherols and carotenoids are the most appropriate due to their lipophilic characteristics. Significant suppression of the oxidation process was observed for bulk salmon oil in the presence of α-tocopherol and astaxanthin [17]. Other less lipophilic

• natural antioxidants are flavonoids, anthocyanins and their glycosides. Huber and collaborators [18] revealed the inhibition of PUFA oxidation by quercetin and its 3-O-glucoside. They were as effective as butylated hydroxytoluene (BHT, a synthetic antioxidant) against the oxidation of DHA and methylated

Determination of formation constants and structural characterization of cyclodextrin inclusion complexes with two phenolic isomers: carvacrol and thymol

• Miriana Kfoury,
• David Landy,
• Steven Ruellan,
• Lizette Auezova,
• Hélène Greige-Gerges and
• Sophie Fourmentin

Beilstein J. Org. Chem. 2016, 12, 29–42, doi:10.3762/bjoc.12.5

• antioxidants such as butylated hydroxytoluene (BHT) or butylated hydroxyanisole (BHA), suspected to be carcinogenic [13][14]. However, the major drawbacks for their use in food are their low aqueous solubility that limits their homogenous dispersion and their contact with pathogens [15], their susceptibility

• act as secondary antioxidants and improve the activity of antioxidants [55]. Altogether data indicated that CDs could increase the half-life of antioxidant compounds and broaden their applications. Conclusion In this work, we clearly demonstrated that CDs could successfully encapsulate 1 and 2

Dicarboxylic esters: Useful tools for the biocatalyzed synthesis of hybrid compounds and polymers

• Ivan Bassanini,
• Karl Hult and
• Sergio Riva

Beilstein J. Org. Chem. 2015, 11, 1583–1595, doi:10.3762/bjoc.11.174

• 18, obtained by linking together a steroid (cortisone, 14) and an alkaloid (colchicoside, 15; thiocolchicoside, 16). Worth of notice the use, among others, of activated esters of dithio-dicarboxylic acids, in 18. More recently Kren and coworkers have synthesized hybrid dimeric antioxidants 23–25