One-pot synthesis of oxazolidinones and five-membered cyclic carbonates from epoxides and chlorosulfonyl isocyanate: theoretical evidence for an asynchronous concerted pathway

• Esra Demir,
• Ozlem Sari,
• Yasin Çetinkaya,
• Ufuk Atmaca,
• Safiye Sağ Erdem and
• Murat Çelik

Beilstein J. Org. Chem. 2020, 16, 1805–1819, doi:10.3762/bjoc.16.148

• (trade name Sivextro), which exhibits antibiotic activity is another oxazolidinone drug approved by the FDA in 2014 [11]. Befloxatone and toloxatone, N-substituted phenyloxazolidinone derivatives, are reversible inhibitors of monoamine oxidase (MAO) [12][13]. N-Aryloxazolidinedione compounds, which are

Facile synthesis of 7-alkyl-1,2,3,4-tetrahydro-1,8-naphthyridines as arginine mimetics using a Horner–Wadsworth–Emmons-based approach

• Rhys A. Lippa,
• John A. Murphy and
• Tim N. Barrett

Beilstein J. Org. Chem. 2020, 16, 1617–1626, doi:10.3762/bjoc.16.134

• inhibitors based on the tripeptide sequence Arg–Gly–Asp (RGD) are potential therapeutics for the treatment of idiopathic pulmonary fibrosis (IPF). Herein, we describe an expeditious three-step synthetic sequence of Horner–Wadsworth–Emmons olefination, diimide reduction, and global deprotection to synthesise

• ; Introduction Tetrahydronaphthyridines are prominent in peptidomimetic pharmaceuticals as arginine mimetics and they are widely used in Arg–Gly–Asp (RGD) peptide mimetics such as αv integrin inhibitors [1]. Tetrahydronaphthyridines represent less basic but more permeable alternatives to arginine (pKa ≈ 7 versus

• 13.8) [1] replicating the side-on salt-bridge binding interaction made between the guanidinium functionality of arginine and an aspartic acid residue in the protein. Consequently, this moiety has been used in various integrin inhibitors (Figure 1) [2][3][4][5][6][7][8]. Current routes to install

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

• rutaceous plants [9]. Examples from microbes include chymase inhibitors SF2809-I to VI from an actinomycete of the genus Dactylosporangium [10], a quorum sensing signaling molecule 2,4-dihydroxyquinoline (DHQ, 4) from Gram-negative bacteria Pseudomonas aeruginosa and Burkholderia thailandensis, [7], and 4-O

One-pot synthesis of 1,3,5-triazine-2,4-dithione derivatives via three-component reactions

• Gui-Feng Kang and
• Gang Zhang

Beilstein J. Org. Chem. 2020, 16, 1447–1455, doi:10.3762/bjoc.16.120

• anticancer [10][11], antimicrobial [12], antiviral agents [13][14], and eosinophilia inhibitors [15]. Therefore, it is highly desirable to develop efficient and practical synthetic methods for triazinethione architectures and to expand the structure diversity of this class of compounds for medicinal

The McKenna reaction – avoiding side reactions in phosphonate deprotection

• Katarzyna Justyna,
• Joanna Małolepsza,
• Damian Kusy,
• Waldemar Maniukiewicz and
• Katarzyna M. Błażewska

Beilstein J. Org. Chem. 2020, 16, 1436–1446, doi:10.3762/bjoc.16.119

• Michael acceptor, as such is currently popular in the development of covalent inhibitors [43]. The reaction was carried out in the presence of 12 equiv BTMS at 35 °C. The disappearance of the signals originating from the vinyl protons (multiplets at δ 5.56–5.66 and 5.95–6.10 ppm) and the appearance of the

Recent synthesis of thietanes

• Jiaxi Xu

Beilstein J. Org. Chem. 2020, 16, 1357–1410, doi:10.3762/bjoc.16.116

• discovery of pan-CDK inhibitors. For this, 3-bromo-2,2-bis(bromomethyl)propan-1-ol (20) was transformed into 3-bromomethyl-3-hydroxymethyl-1-tosylazetidine (21), which was treated with Ph3P/CBr4 to yield 3,3-bis(bromomethyl)-1-tosylazetidine (22) in 52% yield. The double displacement of 3,3-bis(bromomethyl

• -2,4-diol and treated it with sodium sulfide to afford 2,4-di(benzyloxymethyl)thietane (49). Compound 49 was then further transformed into two different anomeric thietanose nucleosides 1 and 50 [4] (Scheme 11). In the development of novel class I phosphoinositide 3-kinase (PI3k) inhibitors, 6-bromo-3,3

Synthesis, antiinflammatory activity, and molecular docking studies of bisphosphonic esters as potential MMP-8 and MMP-9 inhibitors

• Abimelek Cortes-Pacheco,
• María Adelina Jiménez-Arellanes,
• Francisco José Palacios-Can,
• José Antonio Valcarcel-Gamiño,
• Rodrigo Said Razo-Hernández,
• María del Carmen Juárez-Vázquez,
• Adolfo López-Torres and
• Oscar Abelardo Ramírez-Marroquín

Beilstein J. Org. Chem. 2020, 16, 1277–1287, doi:10.3762/bjoc.16.108

• ]. Specifically, bisphosphonates act as osteoclast resorption inhibitors, augmenting the bone density and preventing osteoporosis [4]. Moreover, some bisphosphonates have gained attention as potential antiinflammatory agents by in vitro and in vivo assays [5][6][7][8]. Additionally, bisphosphonates have been

• molecular docking studies were performed to account for a possible action mechanism as MMP-8 and MMP-9 inhibitors. Results and Discussion Chemistry As part of our ongoing interest in the discovery of new antiinflammatory agents, our research group have previously addressed the synthesis and in vivo

• mechanism of action of the bisphosphonates 3–6, we propose that the tested derivatives are acting as MMP inhibitors. In this respect, MMP-8 and MMP-9 isoenzymes are related to inflammatory processes in different tissues [32][33][34][35]. Furthermore, for MMP-8 and MMP-9, enzyme–inhibitor interaction modes

Synthesis of pyrrolidinedione-fused hexahydropyrrolo[2,1-a]isoquinolines via three-component [3 + 2] cycloaddition followed by one-pot N-allylation and intramolecular Heck reactions

• Xiaoming Ma,
• Suzhi Meng,
• Xiaofeng Zhang,
• Qiang Zhang,
• Shenghu Yan,
• Yue Zhang and
• Wei Zhang

Beilstein J. Org. Chem. 2020, 16, 1225–1233, doi:10.3762/bjoc.16.106

• crispine A isolated from Carduus crispus L has antitumor activity [3]. Erythrina alkaloids have curare-like neuromuscular blocking activities [4], and also antioxidant activity against DPPH free radicals [5]. Lamellarins isolated from marine invertebrates [6] are inhibitors for HIV-1 integrase and also

Anthelmintic drug discovery: target identification, screening methods and the role of open science

• Frederick A. Partridge,
• Ruth Forman,
• Carole J. R. Bataille,
• Graham M. Wynne,
• Marina Nick,
• Angela J. Russell,
• Kathryn J. Else and
• David B. Sattelle

Beilstein J. Org. Chem. 2020, 16, 1203–1224, doi:10.3762/bjoc.16.105

• developed helminth analysis methods using CellProfiler. A virtual screening approach was used to identify inhibitors of S. mansoni thioredoxin glutathione reductase [140]. These virtual hits were then tested in a CellProfiler-based high content screen using S. mansoni schistosomula, which determines both

Synthesis of esters of diaminotruxillic bis-amino acids by Pd-mediated photocycloaddition of analogs of the Kaede protein chromophore

• Esteban P. Urriolabeitia,
• Pablo Sánchez,
• Alexandra Pop,
• Cristian Silvestru,
• Eduardo Laga,
• Ana I. Jiménez and
• Carlos Cativiela

Beilstein J. Org. Chem. 2020, 16, 1111–1123, doi:10.3762/bjoc.16.98

• in the last few years due to the discovery that truxillic acid derivatives are inhibitors of FABP (fatty acid binding proteins), which are responsible for the cellular reuptake of anandamide, an endocannabinoid neurotransmitter, and that they can be involved in a very efficient treatment for chronic

A simple and easy to perform synthetic route to functionalized thienyl bicyclo[3.2.1]octadienes

• Dragana Vuk,
• Irena Škorić,
• Valentina Milašinović,
• Krešimir Molčanov and
• Željko Marinić

Beilstein J. Org. Chem. 2020, 16, 1092–1099, doi:10.3762/bjoc.16.96

• the HRMS measurements is appreciated. Funding The University of Zagreb short term scientific support under the title “Synthesis and functionalization of novel (hetero)polycyclic photoproducts as cholinesterase inhibitors” is gratefully acknowledged.

Palladium-catalyzed regio- and stereoselective synthesis of aryl and 3-indolyl-substituted 4-methylene-3,4-dihydroisoquinolin-1(2H)-ones

• Valeria Nori,
• Antonio Arcadi,
• Armando Carlone,
• Fabio Marinelli and
• Marco Chiarini

Beilstein J. Org. Chem. 2020, 16, 1084–1091, doi:10.3762/bjoc.16.95

• active small molecules that exhibit antihypertensive activity [7][8]. Moreover, these heterocycles can be used as 5-HT3 antagonists [9], rho kinase inhibitors [10], thymidylate synthetase inhibitors [11], PARP-1 inhibitors [12], melatonin MT1 and MT2 receptor agonist [13], and fascin-targeted

Fluorinated phenylalanines: synthesis and pharmaceutical applications

• Laila F. Awad and
• Mohammed Salah Ayoup

Beilstein J. Org. Chem. 2020, 16, 1022–1050, doi:10.3762/bjoc.16.91

• over the last few decades. ᴅ- or ʟ-fluorinated phenylalanines have had considerable industrial and pharmaceutical applications and they have been expanded also to play an important role as potential enzyme inhibitors as well as therapeutic agents and topography imaging of tumor ecosystems using PET

• , geometry, conformation, reactivity, and moreover the bioavailability of the analogue [1]. Fluorinated amino acids (FAAs) have considerable industrial and pharmaceutical potential [2]. Also, they have played an important role as enzyme inhibitors as well as therapeutic agents [3][4]. Moreover, they modulate

• ees < 98%. The products were hydrolyzed and deprotected in a two-step protocol to afford the desired products 77a,b [55] (Scheme 18). Interestingly substitution of Phe by either 77b or 77a in the proteasome inhibitors bortezomib or epoxymicin, led to an increase in the efficiency as anticancer

Design and synthesis of diazine-based panobinostat analogues for HDAC8 inhibition

• Sivaraman Balasubramaniam,
• Sajith Vijayan,
• Liam V. Goldman,
• Xavier A. May,
• Kyra Dodson,
• Sweta Adhikari,
• Fatima Rivas,
• Davita L. Watkins and
• Shana V. Stoddard

Beilstein J. Org. Chem. 2020, 16, 628–637, doi:10.3762/bjoc.16.59

• inhibitors (HDACis). The targets of interest (TOI) are analogues of panobinostat, one of the most potent and versatile HDACi reported. By simply replacing the phenyl core of panobinostat with that of a diazine derivative, docking studies against HDAC2 and HDAC8 revealed that the four analogues exhibit

• lay the foundation for future design strategies toward more potent HDACis for HDAC8 isozymes and further therapeutic applications for neuroblastoma. Keywords: diazine; histone deacetylase; inhibitors; isozymes; panobinostat; Introduction One of the most important posttranslational modifications

• development of novel HDAC inhibitors (HDACis) has become a rapidly evolving area where targeted inhibition has emerged in clinical research as a potential therapeutic approach for the treatment of various cancers as well as neurodegenerative disorders and immune related diseases [3][4][5]. Of specific

Exploring the scope of DBU-promoted amidations of 7-methoxycarbonylpterin

• Anna R. Bockman and
• Jeffrey M. Pruet

Beilstein J. Org. Chem. 2020, 16, 509–514, doi:10.3762/bjoc.16.46

• molybdopterin [1]. Owing to this biological relevance, pterins are an attractive building block in the development of various pharmaceuticals, with methotrexate being the most well-known [2]. In addition to pteridine derivatives being used as inhibitors of dihydrofolate reductase and dihydropteroate synthase

• , pterins have been a useful scaffold in the development of inhibitors of ricin [3][4], methionine synthase [5], nitric oxide synthase [6], shigella [7], and aldose reductase [8], as well as for treatment of leishmaniosis [9]. In addition to their therapeutic potential, pterin derivatives have been an

• for ricin toxin A (RTA) inhibitors [14]. By deprotonation of the lactam NH, and conversion to the DBU salt, the pterin easily dissolves in methanol at high concentrations, unprecedented for unfunctionalized pterins. This greatly accelerated the development of a library of bioactive pterins, as it

Synthesis of 4-amino-5-fluoropyrimidines and 5-amino-4-fluoropyrazoles from a β-fluoroenolate salt

• Tobias Lucas,
• Jule-Philipp Dietz and
• Till Opatz

Beilstein J. Org. Chem. 2020, 16, 445–450, doi:10.3762/bjoc.16.41

• nucleoside analogues which can either act as antimetabolites or as nucleoside reverse transcriptase inhibitors (NRTIs). Two of the most common 5-fluoropyrimidines are the cytostatic 5-fluorouracil (1) [27] and the antimycotic prodrug 5-fluorocytosine (2) [28][29], which is also part of the anti-HIV agents

Synthesis and herbicidal activities of aryloxyacetic acid derivatives as HPPD inhibitors

• Man-Man Wang,
• Hao Huang,
• Lei Shu,
• Jian-Min Liu,
• Jian-Qiu Zhang,
• Yi-Le Yan and
• Da-Yong Zhang

Beilstein J. Org. Chem. 2020, 16, 233–247, doi:10.3762/bjoc.16.25

• dioxygenase (HPPD) inhibitors. Preliminary bioassay results reveal that these derivatives are promising Arabidopsis thaliana HPPD (AtHPPD) inhibitors, in particular compounds I12 (Ki = 0.011 µM) and I23 (Ki = 0.012 µM), which exhibit similar activities to that of mesotrione, a commercial HPPD herbicide (Ki

• various species and genera and providing a theoretical basis for the design of inhibitors that are highly selective and safe [2]. In plants, HPPD inhibitors competitively restrain HPPA from chelating to FeII. The production of plastoquinone is inhibited and phytoene is accumulated when the transformation

• of HPPA to HGA is interfered with an HPPD inhibitor [9][10]; consequently, plants become severely damage when exposed to sunlight, ultimately resulting in bleaching symptoms followed by necrosis and death [11][12]. Therefore, HPPD inhibitors play important roles in the herbicide industry. In addition

Potent hemithioindigo-based antimitotics photocontrol the microtubule cytoskeleton in cellulo

• Alexander Sailer,
• Franziska Ermer,
• Yvonne Kraus,
• Rebekkah Bingham,
• Ferdinand H. Lutter,
• Julia Ahlfeld and
• Oliver Thorn-Seshold

Beilstein J. Org. Chem. 2020, 16, 125–134, doi:10.3762/bjoc.16.14

• hemithioindigo-based indanone-like tubulin inhibitors (HITubs) and optimised their cellular potency as antimitotic photopharmaceuticals. These HITubs feature reliable and robust visible-light photoswitching and high fatigue resistance. The use of the hemithioindigo scaffold also permitted us to employ a para

• understanding MT biology; and optogenetic modifications of tubulin have never succeeded. Instead, studies of the roles of MTs in these processes overwhelmingly rely on small molecule tubulin inhibitors [1]. Due to the non-invasiveness and high spatiotemporal precision with which optical stimulation can be

• development beyond classical small molecule inhibitors; since the spatiotemporal complexity inherent to the diversity of tubulin-dependent cellular processes may finally yield to studies that can leverage high-spatiotemporal-specificity optical control to deliver cell-specific, time-reversible modulation of

Functionalization of the imidazo[1,2-a]pyridine ring in α-phosphonoacrylates and α-phosphonopropionates via microwave-assisted Mizoroki–Heck reaction

• Damian Kusy,
• Agata Wojciechowska,
• Joanna Małolepsza and
• Katarzyna M. Błażewska

Beilstein J. Org. Chem. 2020, 16, 15–21, doi:10.3762/bjoc.16.3

• composed of both, an imidazo[1,2-a]pyridine ring and the phosphoryl group. The combination of these functional groups can be found in bisphosphonates and phosphonocarboxylates [8][9][10] – inhibitors of the therapeutically important enzymes, farnesyl pyrophosphate synthase (FPPS) and Rab geranylgeranyl

• transferase (RGGT), respectively. Results and Discussion We have previously synthesized a number of phosphonocarboxylates (PC) to study their structure–activity relationship with RGGT, using compounds 1 and 2 as advanced intermediates in the synthesis of RGGT inhibitors (Figure 1) [10][11]. We have found that

Synthesis of C-glycosyl phosphonate derivatives of 4-amino-4-deoxy-α-ʟ-arabinose

• Lukáš Kerner and
• Paul Kosma

Beilstein J. Org. Chem. 2020, 16, 9–14, doi:10.3762/bjoc.16.2

• cationic antimicrobial peptides with the negatively charged phosphate and carboxylate groups in LPS domains. Suitable inhibitors intercepting the attachment of Ara4N units to the lipid A and inner core region might restore sensitivity towards the cationic antimicrobial drugs as a novel approach to combat

• the looming antibiotic crisis [5]. 4-Amino-4-deoxy-ʟ-arabinose units are activated as the phosphodiester-linked undecaprenyl derivative [6], which is then transferred by the action of several Ara4N transferases (ArnT, Figure 1) [7]. The synthesis of potential inhibitors of the biosynthesis of Ara4N

• have frequently been exploited as potential inhibitors for glycosyl transferases since the carbon–phosphorus bond is not hydrolyzed in the active site of glycosyl transferases [10][11][12][13]. Herein, we report on the synthesis of α-anomeric C-arabinosyl methylphosphonate ester derivatives as model

SnCl₄-catalyzed solvent-free acetolysis of 2,7-anhydrosialic acid derivatives

• Kesatebrhan Haile Asressu and
• Cheng-Chung Wang

Beilstein J. Org. Chem. 2019, 15, 2990–2999, doi:10.3762/bjoc.15.295

• synthetic applications of 2,7-anhydro-Neu5Ac are available in the literature. Previously, we successfully constructed the fucosyl α(1→4) to Neu5Ac linkage of ganglioside HPG-7 using 2,7-anhydro-Neu5Ac derivatives as acceptors [6]. For utilization as selective sialidase inhibitors, Chen’s and Juge’s groups

• in the synthesis of inhibitors for N-acetylneuraminidases from different sources [42]. The ring opening of 5 was not trivial since the substrate had a sterically hindered quaternary anomeric center, unlike the tertiary anomeric center C-1 of 1,6-anhydro sugars [29][30][31][32][33][43]. Furthermore

Pigmentosins from Gibellula sp. as antibiofilm agents and a new glycosylated asperfuran from Cordyceps javanica

• Soleiman E. Helaly,
• Wilawan Kuephadungphan,
• Patima Phainuphong,
• Mahmoud A. A. Ibrahim,
• Kanoksri Tasanathai,
• Suchada Mongkolsamrit,
• Janet Jennifer Luangsa-ard,
• Souwalak Phongpaichit,
• Vatcharin Rukachaisirikul and
• Marc Stadler

Beilstein J. Org. Chem. 2019, 15, 2968–2981, doi:10.3762/bjoc.15.293

• in combination with biofilm inhibitors [7]. Since finding an effective strategy to control biofilm formation remains a challenge, the effort to search for an effective antibiofilm agent was herein made. Invertebrate-pathogenic fungi, in particular the spider-pathogenic fungi, have recently proved to

• be a promising source of bioactive compounds [8][9][10]. Thus, during the current study, which is part of a project aiming to discover novel biofilm inhibitors from Thai fungi [11], a number of invertebrate-pathogenic fungi collected from various parts of Thailand were studied for production of

• . Conclusively, even though the mode of action of the pigmentosins remains to be studied, they constitute promising candidates for combination therapy with existing or novel antibiotics. So far, beauverolides have been found to be potent calmodulin (CaM) inhibitors [33], antiatherosclerotic agents [34], acyl-CoA

Chemical synthesis of tripeptide thioesters for the biotechnological incorporation into the myxobacterial secondary metabolite argyrin via mutasynthesis

• David C. B. Siebert,
• Roman Sommer,
• Domen Pogorevc,
• Michael Hoffmann,
• Silke C. Wenzel,
• Rolf Müller and
• Alexander Titz

Beilstein J. Org. Chem. 2019, 15, 2922–2929, doi:10.3762/bjoc.15.286

• identified. In addition, the development of new β-lactamase inhibitors is ongoing and may restore the activity of known β-lactams against β-lactamase-producing strains [2]. Unfortunately, most of these antibiotics rely on known modes of action and do not target novel binding sites. To circumvent established

One-pot synthesis of substituted pyrrolo[3,4-b]pyridine-4,5-diones based on the reaction of N-(1-(4-hydroxy-6-methyl-2-oxo-2H-pyran-3-yl)-2-oxo-2-arylethyl)acetamide with amines

• Valeriya G. Melekhina,
• Andrey N. Komogortsev,
• Boris V. Lichitsky,
• Vitaly S. Mityanov,
• Artem N. Fakhrutdinov,
• Arkady A. Dudinov,
• Vasily A. Migulin,
• Yulia V. Nelyubina,
• Elizaveta K. Melnikova and
• Michail M. Krayushkin

Beilstein J. Org. Chem. 2019, 15, 2840–2846, doi:10.3762/bjoc.15.277

• tested as dipeptidyl peptidase-4 (DPP4) inhibitors [4][5][6][7]. From the obtained results, the authors suggested these compounds as effective therapeutic agents for the treatment of diabetes mellitus. Further, it was shown that several synthetic molecules with a pyrrolo[3,4-b]pyridin-5-one core display

Palladium-catalyzed synthesis and nucleotide pyrophosphatase inhibition of benzo[4,5]furo[3,2-b]indoles

• Hoang Huy Do,
• Saif Ullah,
• Alexander Villinger,
• Joanna Lecka,
• Jean Sévigny,
• Peter Ehlers,
• Jamshed Iqbal and
• Peter Langer

Beilstein J. Org. Chem. 2019, 15, 2830–2839, doi:10.3762/bjoc.15.276

• first time, a study related to the activity of the products as nucleotide pyrophosphatase inhibitors. In this context, we also studied the biological activity of previously synthesized diindolofurans and the results are compared with those of benzofuroindoles. Results and Discussion Following a

• changes of the substitution pattern allow for a modification of the selectivity and activity of these compounds to these enzymes. Docking studies of h-ENPP1 inhibitors Molecular docking of the most potent compounds 5c and 6a (for ENPP1) and for 6e (exhibiting dual inhibition for both isozymes) were

• -shaped and π–alkyl related bindings were noticed, connecting Ile235, Phe220, Ala546, Trp322 and Ile419. The fluorine atom was perceived interacting with Ile419. Docking studies of h-ENPP3 inhibitors The binding of ENPP3 was studied for selective inhibitor 5e. A dual affinity was observed for 5h and 6e