A Streptomyces P450 enzyme dimerizes isoflavones from plants

• Run-Zhou Liu,
• Shanchong Chen and
• Lihan Zhang

Beilstein J. Org. Chem. 2022, 18, 1107–1115, doi:10.3762/bjoc.18.113

• P450 enzymes in total. To investigate whether P450 enzymes mediate this dimerization reaction, we first employed a chemical genetics screening using three P450 inhibitors, CTA (strong inhibitor), FCA (moderate inhibitor), and RVT (polyphenol inhibitor) [23][24]. All three agents reduced the production

• Experimental section, 254 nm). b) Chemical genetics experiments indicated three P450 inhibitors could reduce the production of dimers derived from 4 (analytical method B to better analyze the isoflavone region, 254 nm). CTA: clotrimazole (2.5 µM), FCA: fluconazole (1000 µM), RVT: resveratrol (100 µM). CYP158C1

Scope of tetrazolo[1,5-a]quinoxalines in CuAAC reactions for the synthesis of triazoloquinoxalines, imidazoloquinoxalines, and rhenium complexes thereof

• Laura Holzhauer,
• Chloé Liagre,
• Olaf Fuhr,
• Nicole Jung and
• Stefan Bräse

Beilstein J. Org. Chem. 2022, 18, 1088–1099, doi:10.3762/bjoc.18.111

• of a metal complex with an inverse triazoloquinoxaline ligand [12]. Imidazo[1,2-a]quinoxalines have been reported to possess anticancer and antitumor properties [27][28] and show activity as adenosine receptor antagonists [29] as well as PDE4 inhibitors [30]. The reaction of ring-fused tetrazoles to

Cathodic generation of reactive (phenylthio)difluoromethyl species and its reactions: mechanistic aspects and synthetic applications

• Sadanobu Iwase,
• Shinsuke Inagi and
• Toshio Fuchigami

Beilstein J. Org. Chem. 2022, 18, 872–880, doi:10.3762/bjoc.18.88

• )difluoromethyl group (ArSCF2) have potential biological applications such as anti-HIV-1 reverse transcriptase inhibitors and agrochemical applications [3][4]. Reurakul and Pohmakotr et al. carried out the reaction of PhSCF2Br with SmI2 in THF/iPrOH to generate PhSCF2 radicals followed by trapping with various

Synthesis and HDAC inhibitory activity of pyrimidine-based hydroxamic acids

• Virginija Jakubkiene,
• Gabrielius Ernis Valiulis,
• Markus Schweipert,
• Asta Zubriene,
• Daumantas Matulis,
• Franz-Josef Meyer-Almes and
• Sigitas Tumkevicius

Beilstein J. Org. Chem. 2022, 18, 837–844, doi:10.3762/bjoc.18.84

• to differently substituted pyrimidine rings via a methylene group bridge of varying length as potential HDAC inhibitors is described. The target compounds were obtained by alkylation of 2-(alkylthio)pyrimidin-4(3H)-ones with ethyl 2-bromoethanoate, ethyl 4-bromobutanoate, or methyl 6-bromohexanoate

• the corresponding hydroxamic acids. The synthesized hydroxamic acids were tested as inhibitors of the HDAC4 and HDAC8 isoforms. Among the synthesized pyrimidine-based hydroxamic acids N-hydroxy-6-[6-methyl-2-(methylthio)-5-propylpyrimidin-4-yloxy]hexanamide was found to be the most potent inhibitor of

• both the HDAC4 and HDAC8 isoforms, with an IC50 of 16.6 µM and 1.2 µM, respectively. Keywords: alkylation; aminolysis; HDAC inhibitors; hydroxamic acid; pyrimidine; Introduction Histone deacetylases (HDACs) are a family of intracellular proteins responsible for removing acetyl groups in histones

Synthesis of bis-spirocyclic derivatives of 3-azabicyclo[3.1.0]hexane via cyclopropene cycloadditions to the stable azomethine ylide derived from Ruhemann's purple

• Alexander S. Filatov,
• Olesya V. Khoroshilova,
• Anna G. Larina,
• Vitali M. Boitsov and
• Alexander V. Stepakov

Beilstein J. Org. Chem. 2022, 18, 769–780, doi:10.3762/bjoc.18.77

• found in natural compounds [9][10][11]. It is used in pharmaceuticals [12][13][14][15] and key intermediates [16][17]. Compounds containing a 3-azabicyclo[3.1.0]hexane moiety are antagonists of morphine-induced antinociception [18], histone deacetylase inhibitors [13], and opioid receptor antagonists

Structural basis for endoperoxide-forming oxygenases

• Takahiro Mori and
• Ikuro Abe

Beilstein J. Org. Chem. 2022, 18, 707–721, doi:10.3762/bjoc.18.71

• are well conserved. While COX-1 is a constitutive enzyme present in most tissues, COX-2 is an isoenzyme induced in response to tumor promoters, growth factors, and cytokines [38][39][40]. Therefore, many COX-2 selective inhibitors are clinically used for treatments of inflammation, cancers, and pain

Shift of the reaction equilibrium at high pressure in the continuous synthesis of neuraminic acid

• Jannis A. Reich,
• Miriam Aßmann,
• Kristin Hölting,
• Paul Bubenheim,
• Jürgen Kuballa and
• Andreas Liese

Beilstein J. Org. Chem. 2022, 18, 567–579, doi:10.3762/bjoc.18.59

• stability investigations, it can be concluded that both selected enzyme preparations have adequate stability for the continuous application under high pressure. Kinetics Reaction kinetics were first measured for the immobilized epimerase. In the absence of inhibitors or backward reactions, the reaction rate

Chemistry of polyhalogenated nitrobutadienes, 17: Efficient synthesis of persubstituted chloroquinolinyl-1H-pyrazoles and evaluation of their antimalarial, anti-SARS-CoV-2, antibacterial, and cytotoxic activities

• Viktor A. Zapol’skii,
• Isabell Berneburg,
• Ursula Bilitewski,
• Melissa Dillenberger,
• Katja Becker,
• Stefan Jungwirth,
• Aditya Shekhar,
• Bastian Krueger and
• Dieter E. Kaufmann

Beilstein J. Org. Chem. 2022, 18, 524–532, doi:10.3762/bjoc.18.54

• pyrazole 7. A plausible mechanism for the formation of pyrazole 7. Synthesis of pyrazoles 9 and sulfoxide 10d. Synthesis of pyrazole 11. EC50 values of newly synthesized inhibitors on P. falciparum 3D7. Supporting Information Supporting Information File 152: Experimental procedures, characterization data

Unexpected chiral vicinal tetrasubstituted diamines via borylcopper-mediated homocoupling of isatin imines

• Marco Manenti,
• Leonardo Lo Presti,
• Giorgio Molteni and
• Alessandra Silvani

Beilstein J. Org. Chem. 2022, 18, 303–308, doi:10.3762/bjoc.18.34

• commonly utilized as key intermediates for the synthesis of boron-containing peptidomimetics, which have been demonstrated to be efficient covalent ligands and valuable protease inhibitors endowed with various biological activities [5][6]. Going on with our interest in the synthesis of 3,3-disubstituted

Anomeric 1,2,3-triazole-linked sialic acid derivatives show selective inhibition towards a bacterial neuraminidase over a trypanosome trans-sialidase

• Peterson de Andrade,
• Sanaz Ahmadipour and
• Robert A. Field

Beilstein J. Org. Chem. 2022, 18, 208–216, doi:10.3762/bjoc.18.24

• natural substrate for sialidases and its chemical modification has been a useful approach to generate potent and selective inhibitors. Aiming at advancing the discovery of selective Trypanosoma cruzi trans-sialidase (TcTS) inhibitors, we have synthesised a small series of anomeric 1,2,3-triazole-linked

• differentiate both enzymes. Moreover, such selectivity might be reasoned based on a possible steric hindrance caused by a bulky hydrophobic loop that sits over the TcTS active site and may prevent the hydrophobic inhibitors from binding. The present study is a step forward in exploiting subtle structural

• the development of potent and selective inhibitors can serve as the basis for new therapeutics [3]. Despite the low primary sequence similarity among human, viral and non-viral sialidases (bacterial and protozoa), they all share a similar catalytic domain with active site residues highly conserved

Synthesis and late stage modifications of Cyl derivatives

• Phil Servatius and
• Uli Kazmaier

Beilstein J. Org. Chem. 2022, 18, 174–181, doi:10.3762/bjoc.18.19

• direct access to cyclopeptides related to naturally occurring histone deacetylase (HDAC) inhibitors Cyl-1 and Cyl-2. Late stage modifications on the unsaturated amino acid side chain allow the introduction of functionalities which might coordinate to metal ions in the active center of metalloproteins

• ]. Three of these enzyme classes (I, II, and IV) contain Zn2+ within the active site, and therefore these enzymes can be affected by typical Zn2+-binding HDAC inhibitors. In cellular systems, an acetylated lysine of a histone is entering the cavity of the active site and gets coordinated to Zn2

• +. Subsequent attack of water forms a tetrahedral intermediate which results in a cleavage of the acetylated lysine. Most HDAC inhibitors act as substrate mimics and contain a zinc-binding motif. They competitively interact with the HDACs to form stable intermediates and therewith block the active site. Many

Ready access to 7,8-dihydroindolo[2,3-d][1]benzazepine-6(5H)-one scaffold and analogues via early-stage Fischer ring-closure reaction

• Irina Kuznetcova,
• Felix Bacher,
• Daniel Vegh,
• Hsiang-Yu Chuang and
• Vladimir B. Arion

Beilstein J. Org. Chem. 2022, 18, 143–151, doi:10.3762/bjoc.18.15

• University of Technology in Bratislava, Radlinského 9, SK-81237 Bratislava, Slovak Republic Institute of Organic Chemistry of the University of Vienna, Währinger Strasse 38, 1090 Vienna, Austria 10.3762/bjoc.18.15 Abstract Paullone isomers are known as inhibitors of tubulin polymerase and cyclin dependent

1,2-Naphthoquinone-4-sulfonic acid salts in organic synthesis

• Ruan Carlos B. Ribeiro,
• Patricia G. Ferreira,
• Amanda de A. Borges,
• Luana da S. M. Forezi,
• Fernando de Carvalho da Silva and
• Vitor F. Ferreira

Beilstein J. Org. Chem. 2022, 18, 53–69, doi:10.3762/bjoc.18.5

• synthesis of a series of amino-N-methylated compounds 36 and phenoxy-1,2-naphthoquinones 35 with a carbon skeleton similar to β-lapachone (11), which could modulate hCE1 activity. Studies have shown that amino-N-methylated-1,2-naphthoquinones 36 are more selective and potent inhibitors than phenoxy-1,2

Efficient N-arylation of 4-chloroquinazolines en route to novel 4-anilinoquinazolines as potential anticancer agents

• Rodolfo H. V. Nishimura,
• Thiago dos Santos,
• Valter E. Murie,
• Luciana C. Furtado,
• Leticia V. Costa-Lotufo and
• Giuliano C. Clososki

Beilstein J. Org. Chem. 2021, 17, 2968–2975, doi:10.3762/bjoc.17.206

• malignant tumors, including platelet-derived growth factor receptor beta (PDGFR-β), vessel epidermal growth factor receptor (VEGFR-2), and epidermal growth factor receptor (EGFR) [5][6]. In addition, these compounds may act as vascular disrupting agents and tubulin polymerization inhibitors, contributing to

• apoptosis [7]. Figure 1 highlights the structures of three EGFR inhibitors approved by the United States Food and Drug Administration (FDA) and one known tubulin inhibitor: erlotinib (1), gefitinib (2), lapatinib (3), and MPC-6827 – verubulin (4) [5][7]. Given that 4-anilinoquinazolines are potential

Iron-catalyzed domino coupling reactions of π-systems

• Austin Pounder and
• William Tam

Beilstein J. Org. Chem. 2021, 17, 2848–2893, doi:10.3762/bjoc.17.196

• reaction proceeds via a radical mechanism (path iii) [77], although use of radical inhibitors had little impact on the success of the reaction. It seems unlikely a radical pathway is involved in the reaction mechanism; however, it cannot be categorically excluded. In 2021, the Koh group demonstrated the

The PIFA-initiated oxidative cyclization of 2-(3-butenyl)quinazolin-4(3H)-ones – an efficient approach to 1-(hydroxymethyl)-2,3-dihydropyrrolo[1,2-a]quinazolin-5(1H)-ones

• Alla I. Vaskevych,
• Nataliia O. Savinchuk,
• Ruslan I. Vaskevych,
• Eduard B. Rusanov,
• Oleksandr O. Grygorenko and
• Mykhailo V. Vovk

Beilstein J. Org. Chem. 2021, 17, 2787–2794, doi:10.3762/bjoc.17.189

• anti-inflammatory [9], antibacterial [10], antiarrythmic [11] activity; some representatives are CNS suppressors and poly-ADP ribose polymerase (PARP) inhibitors [12] (see Figure 1). Several approaches to obtain 2,3-dihydropyrrolo[1,2-a]quinazolin-5(1H)-one derivatives of type 1 are known in the

Highly stereocontrolled total synthesis of racemic codonopsinol B through isoxazolidine-4,5-diol vinylation

• Lukáš Ďurina,
• Anna Ďurinová,
• František Trejtnar,
• Ľuboš Janotka,
• Lucia Messingerová,
• Jana Doháňošová,
• Ján Moncol and
• Róbert Fischer

Beilstein J. Org. Chem. 2021, 17, 2781–2786, doi:10.3762/bjoc.17.188

• naturally occurring (−)-codonopsinol B (1) and its N-nor-methyl analogue 2 were found to be effective α-glucosidase inhibitors, their racemic forms showed no evident antiproliferative activities against the selected human cancer cell lines U87-MG, HepG2, JEG-3 and MOLM-13 as well as immortalized proximal

The ethoxycarbonyl group as both activating and protective group in N-acyl-Pictet–Spengler reactions using methoxystyrenes. A short approach to racemic 1-benzyltetrahydroisoquinoline alkaloids

• Marco Keller,
• Karl Sauvageot-Witzku,
• Franz Geisslinger,
• Nicole Urban,
• Michael Schaefer,
• Karin Bartel and
• Franz Bracher

Beilstein J. Org. Chem. 2021, 17, 2716–2725, doi:10.3762/bjoc.17.183

• approved P-gp inhibitors are available in clinics [50]. Further, structurally related molecules, like the seco-analogues dauricine and daurisoline and the truncated bisbenzylisoquinoline muraricine (Supporting Information File 1, Figure S1) also show [51] P-gp inhibitory potential, so we investigated the

Synthetic strategies toward 1,3-oxathiolane nucleoside analogues

• Umesh P. Aher,
• Dhananjai Srivastava,
• Girij P. Singh and
• Jayashree B. S

Beilstein J. Org. Chem. 2021, 17, 2680–2715, doi:10.3762/bjoc.17.182

• as zidovudine, didanosine, zalcitabine, stavudine, lamivudine (1), and abacavir (a carbanucleoside) for treating HIV infection, along with protease and nonnucleoside reverse transcriptase inhibitors (NNRTIs). Phosphorylation of 1,3-oxathiolane nucleosides, such as 3TC (1) and FTC (2), occurs in vivo

• to compete with natural deoxynucleotides for incorporation into (viral) DNA. Chain elongation via reverse transcriptase is thus inhibited. This class of drugs is referred to as nucleoside reverse transcriptase inhibitors (NRTIs). In NRTIs, 3TC (1) possesses chemical and biological properties, a

• inhibitors [26][27][28]. 3TC (1) has a β-ʟ-oxathiolane ring structure, instead of the ribose ring in the canonical nucleosides, and studies have shown that the triphosphate of 1 (i.e., 3TCTP) inhibits reverse transcriptase due to DNA chain termination [26][29][30]. In comparison to some of the other NRTIs

Strategies for the synthesis of brevipolides

• Yudhi D. Kurniawan and
• A'liyatur Rosyidah

Beilstein J. Org. Chem. 2021, 17, 2399–2416, doi:10.3762/bjoc.17.157

• hydrogenated brevipolide derivative. It is interesting to note that all the brevipolides A–J (1–10) pose the conserved stereocenters and bear a cyclopropyl unit in the core structure, which are in agreement with the prior structural assignment of compounds 7–9, previously identified as unnamed inhibitors for

• ELISA NF-κB assay. Upon the mitochondrial transmembrane potential assay, three members demonstrated ED50 values in the nanomolar level [4]. Moreover, three of the members were identified as inhibitors of the chemokine receptor CCR5 [11]. Therefore, they are potential agents for treating human

Synthesis and antimicrobial activity of 1H-1,2,3-triazole and carboxylate analogues of metronidazole

• Satya Kumar Avula,
• Syed Raza Shah,
• Khdija Al-Hosni,
• Muhammad U. Anwar,
• Rene Csuk,
• Biswanath Das and
• Ahmed Al-Harrasi

Beilstein J. Org. Chem. 2021, 17, 2377–2384, doi:10.3762/bjoc.17.154

• materials, dyes, agrochemicals, photostabilizers, and corrosion inhibitors (copper alloys) [6]. Incorporation of the 1H-1,2,3-triazole moiety is well known to impact on the physical, chemical and biological potential properties of organic molecules. Due to this reason, many efforts have been exerted to

• metronidazole scaffolds are known to have a large range of biological activities including tumorhypxia agents [8], antiprotozoal activity [9], antimicrobial [10], antitumour [11], carbonic anhydrase IX inhibitors [12], trichomonas vaginalis activity [13], antileishmanial agents [14] (Figure 2). We have recently

(Phenylamino)pyrimidine-1,2,3-triazole derivatives as analogs of imatinib: searching for novel compounds against chronic myeloid leukemia

• Luiz Claudio Ferreira Pimentel,
• Lucas Villas Boas Hoelz,
• Henayle Fernandes Canzian,
• Frederico Silva Castelo Branco,
• Andressa Paula de Oliveira,
• Vinicius Rangel Campos,
• Floriano Paes Silva Júnior,
• Rafael Ferreira Dantas,
• Jackson Antônio Lamounier Camargos Resende,
• Anna Claudia Cunha,
• Nubia Boechat and
• Mônica Macedo Bastos

Beilstein J. Org. Chem. 2021, 17, 2260–2269, doi:10.3762/bjoc.17.144

• 10.3762/bjoc.17.144 Abstract The enzyme tyrosine kinase BCR-Abl-1 is the main molecular target in the treatment of chronic myeloid leukemia and can be competitively inhibited by tyrosine kinase inhibitors such as imatinib. New potential competitive inhibitors were synthesized using the (phenylamino

• chromosome known as Philadelphia (Ph). Ph is the result of the reciprocal chromosomal conversion between the proto-oncogene Abl1 of chromosome 9 and the BCR gene on chromosome 22 [3][4]. Research activity on compounds able to act as protein tyrosine kinase inhibitors (TKIs), which has intensified since the

• TKIs that are even more potent than IMT, such as nilotinib [6][7]. These drugs act as inhibitors at the ATP binding site in the inactive form of BCR-Abl-1, preventing the binding of the protein to ATP in a competitive manner and resulting in the interruption of the substrate phosphorylation process and

Catalyzed and uncatalyzed procedures for the syntheses of isomeric covalent multi-indolyl hetero non-metallides: an account

• Ranadeep Talukdar

Beilstein J. Org. Chem. 2021, 17, 2102–2122, doi:10.3762/bjoc.17.137

• for tryptophan metabolism in the human body. Thus, the inhibition of these enzymes may help in tumor immunotherapy [105][106][107]. Xu recently found indole-2-carboxylic acid derivatives as IDO1/TDO dual inhibitors. In their effort to synthesize the following bis(indol-4-yl)amine derivatives via a

• . Syntheses of bis(indol-2-yl)selanes. Syntheses of bis(indol-3-yl)selanes. Synthesis of bis(indol-2-yl)tellane 147. Synthesis of tris(indolyl)borane 154. Synthesis of bis(indol-4-yl)amines 159. Synthesis of bis(indol-5-yl)amines. Synthesis of 6,5’/6,6’-bis(indolyl)amines. Synthesis of potent HIV-inhibitors

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

• acetylcholinesterase inhibitors [11][12][13], being LSPN223 the most potent compound (Figure 2). Furthermore, coumarin derivatives have been used as fluorescent probes, laser dyes, fluorescent chemosensors, light absorbers for solar cells, optical brighteners, and organic light emitting diodes (OLEDs) [14][15]. From a

• electron-donating and electron-withdrawing substituents. Additionally, the products were evaluated as acetylcholinesterase (AChE) inhibitors and compound 93d showed a promising activity. Gurubrahaman et al. developed a method for the synthesis of (Z)-2-methylenepyrans 96 through a conjugated addition of 4

On the application of 3d metals for C–H activation toward bioactive compounds: The key step for the synthesis of silver bullets

• Renato L. Carvalho,
• Amanda S. de Miranda,
• Mateus P. Nunes,
• Roberto S. Gomes,
• Guilherme A. M. Jardim and
• Eufrânio N. da Silva Júnior

Beilstein J. Org. Chem. 2021, 17, 1849–1938, doi:10.3762/bjoc.17.126

• in good yields (Scheme 39C). The authors used the same methodology to synthesize two 4H-benzo[d][1,3]oxazin-4-one derivatives that act as inhibitors of two enzymes (compounds 130 and 131 in Scheme 39D). The first one is the enzyme C1r serine protease, involved in both inflammation and renal scarring