Synthesis of 1,4-benzothiazinones from acylpyruvic acids or furan-2,3-diones and o-aminothiophenol

• Ekaterina E. Stepanova,
• Maksim V. Dmitriev and
• Andrey N. Maslivets

Beilstein J. Org. Chem. 2020, 16, 2322–2331, doi:10.3762/bjoc.16.193

• )-ones. A selective synthetic approach to 2-hydroxy-2H-1,4-benzothiazin-3(4H)-ones was developed via the solvent-switchable reaction of furan-2,3-diones with o-aminothiophenol. Preliminary biological assays (antimicrobial, acute toxicity) of the new compounds were carried out. Keywords: acylpyruvic acid

• use. Particularly, some enaminones I and II were found to show antioxidant [3], antimycotic [7][8], antimycobacterial [9][10], anti-Alzheimer’s disease (JNK3 inhibitors) [11], platelet aggregation inhibitory [12], antimicrobial [7] and analgesic [13] activities. Enaminones II were reported as

• , inducing its attack on the carbonyl group bearing a higher partially positive charge (for partial charges comparison, see Supporting Information File 1). As we were most interested in the biological activity of BTAs 3, preliminary antimicrobial and toxicity assays of these compounds were carried out

Styryl-based new organic chromophores bearing free amino and azomethine groups: synthesis, photophysical, NLO, and thermal properties

• Anka Utama Putra,
• Deniz Çakmaz,
• Nurgül Seferoğlu,
• Alberto Barsella and
• Zeynel Seferoğlu

Beilstein J. Org. Chem. 2020, 16, 2282–2296, doi:10.3762/bjoc.16.189

• azomethine group are one of the most widely used organic dyes because of their easy and cheap synthetic accessibility through various methodologies and suitable photophysical properties. In addition, they exhibit a broad range of biological activities such as antimicrobial, antifungal, antiviral, and

Access to highly substituted oxazoles by the reaction of α-azidochalcone with potassium thiocyanate

• Mysore Bhyrappa Harisha,
• Pandi Dhanalakshmi,
• Rajendran Suresh,
• Raju Ranjith Kumar and
• Shanmugam Muthusubramanian

Beilstein J. Org. Chem. 2020, 16, 2108–2118, doi:10.3762/bjoc.16.178

• , anti-inflammatory, antimicrobial, anitubercular, psychotropic and anticancer [54][55][56][57][58][59][60]. The marketed cancer drug dasatinib [61] continues to prove its worth. In this work, it is shown that highly substituted oxazoles and aminothiazoles could be accessed directly from the reaction of

Muyocopronones A and B: azaphilones from the endophytic fungus Muyocopron laterale

• Ken-ichi Nakashima,
• Junko Tomida,
• Tomoe Tsuboi,
• Yoshiaki Kawamura and
• Makoto Inoue

Beilstein J. Org. Chem. 2020, 16, 2100–2107, doi:10.3762/bjoc.16.177

• ], tau aggression [3], and heat shock protein 90 [4], in addition to their antimicrobial, cytotoxic, anticancer, and anti-inflammatory effects [5]. To date, over 400 azaphilones have been reported from various fungal strains, the majority of which have been produced by ascomycetes belonging to the

• elucidation, and antimicrobial activity evaluation are described. Results and Discussion Muyocopron laterale ECN279 was isolated from a healthy leaf of Canavalia lineata and identified by sequencing the D1/D2 26S rRNA gene and the internal transcript spacers (ITS) of ribosomal DNA [16]. In a similar manner as

• ,10R,11R) stereoisomer. Finally, since a number of azaphilones have been reported to exhibit antimicrobial activity [5][23], muyocopronones A (1) and B (2) were screened for their antibacterial activity against five strains of Gram-positive bacteria, namely Staphylococcus aureus (PAGU 273T

Synthesis of 3(2)-phosphonylated thiazolo[3,2-a]oxopyrimidines

• Ksenia I. Kaskevich,
• Anastasia A. Babushkina,
• Vladislav V. Gurzhiy,
• Dmitrij M. Egorov,
• Nataly I. Svintsitskaya and
• Albina V. Dogadina

Beilstein J. Org. Chem. 2020, 16, 1947–1954, doi:10.3762/bjoc.16.161

• Thiazolopyrimidines, whose molecules includes both thiazole and pyrimidine rings, have a structural analogy with the antipsychotic drugs ritanserin and setoperone (Figure 1) [1][2][3]. To date, a wide spectrum of biological activity of thiazolopyrimidines has been determined: anticancer [4][5], antimicrobial [6][7

Microwave-assisted efficient one-pot synthesis of N²-(tetrazol-5-yl)-6-aryl/heteroaryl-5,6-dihydro-1,3,5-triazine-2,4-diamines

• Moustafa Sherief Moustafa,
• Ramadan Ahmed Mekheimer,
• Saleh Mohammed Al-Mousawi,
• Mohamed Abd-Elmonem,
• Hesham El-Zorba,
• Afaf Mohamed Abdel Hameed,
• Tahany Mahmoud Mohamed and
• Kamal Usef Sadek

Beilstein J. Org. Chem. 2020, 16, 1706–1712, doi:10.3762/bjoc.16.142

• [2], antitumor [3], anti-HIV [4], inhibitor of Trypanosoma brucei [5], angiogenesis inhibitor [6], antiplasmodial antifolates [7], and antimicrobial [8]. Moreover, and in particular N2,6-disubstituted-1,3,5-triazine-2,4-diamines possess a wide range of chemotherapeutic activities [8][9][10][11

Synthesis of Streptococcus pneumoniae serotype 9V oligosaccharide antigens

• Sharavathi G. Parameswarappa,
• Claney L. Pereira and
• Peter H. Seeberger

Beilstein J. Org. Chem. 2020, 16, 1693–1699, doi:10.3762/bjoc.16.140

• developing countries [3]. With increasing antimicrobial resistance to antibiotics, vaccines are becoming even more important to control these pathogens. Despite the availability of multivalent polysaccharide and glycoconjugate vaccines such as Pneumovax, Prevnar® 13, and Synflorix, pneumonococcal diseases

Synthesis of new dihydroberberine and tetrahydroberberine analogues and evaluation of their antiproliferative activity on NCI-H1975 cells

• Giacomo Mari,
• Lucia De Crescentini,
• Serena Benedetti,
• Francesco Palma,
• Stefania Santeusanio and
• Fabio Mantellini

Beilstein J. Org. Chem. 2020, 16, 1606–1616, doi:10.3762/bjoc.16.133

• , or induce the manifestation of new features. The choice to insert an hydrazonic function on the DHBER skeleton was suggested by its wide range of interesting biological activities like antimicrobial [43], antioxidant [44], analgesic [45], anti-inflammatory [45], antiplatelet [45], anticonvulsant [46

Antibacterial scalarane from Doriprismatica stellata nudibranchs (Gastropoda, Nudibranchia), egg ribbons, and their dietary sponge Spongia cf. agaricina (Demospongiae, Dictyoceratida)

• Cora Hertzer,
• Stefan Kehraus,
• Nils Böhringer,
• Fontje Kaligis,
• Robert Bara,
• Dirk Erpenbeck,
• Gert Wörheide,
• Till F. Schäberle,
• Heike Wägele and
• Gabriele M. König

Beilstein J. Org. Chem. 2020, 16, 1596–1605, doi:10.3762/bjoc.16.132

• sponge prey availability [41]. The isolated metabolites showed various biological activities, such as cytotoxicity, antimicrobial, antiviral and antitumor activities, inhibition of transactivation for the farnesoid X receptor, inhibition of mammalian phospholipase A2, and ichthyotoxicity against the

• -diacetoxy-3,4-methylenedeoxoscalarin. Acknowledgements We thank Dr. Henrik Harms for conducting the antimicrobial assays (grant No 9.818, DZIF, Innovative microbial resources for new anti-infectives). Furthermore, we thank Adrian Galitz for support in the laboratory and Rob W. M. van Soest, Nicole J. de

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

• caused biphasic separation of the mixture. Antimicrobial assay The antimicrobial activity was evaluated by the method described previously [16]. Antioxidant assay The antioxidant activity was evaluated by the method described in [41]. Briefly, luminol (10 μM), H2O2 (1000 μM), and vehicle solvent with or

Photocatalyzed syntheses of phenanthrenes and their aza-analogues. A review

• Alessandra Del Tito,
• Havall Othman Abdulla,
• Davide Ravelli,
• Stefano Protti and
• Maurizio Fagnoni

Beilstein J. Org. Chem. 2020, 16, 1476–1488, doi:10.3762/bjoc.16.123

• corresponding α-amidoalkyl radicals for the synthesis of a set of 6-amidophenanthridines (e.g., 9.3b) with significant antitumor and antimicrobial activities (Scheme 9, path b) [71]. Despite their extensive use, 2-isocyanobiphenyls or related isonitriles were not the only available substrates for the

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

A cyclopeptide and three oligomycin-class polyketides produced by an underexplored actinomycete of the genus Pseudosporangium

• Shun Saito,
• Kota Atsumi,
• Tao Zhou,
• Keisuke Fukaya,
• Daisuke Urabe,
• Naoya Oku,
• Md. Rokon Ul Karim,
• Hisayuki Komaki and
• Yasuhiro Igarashi

Beilstein J. Org. Chem. 2020, 16, 1100–1110, doi:10.3762/bjoc.16.97

• chain of the spiroacetal rings, which showed clear contrast to other oligomycin congeners and related polyketides with ring-truncation or expansion. The new macrolides 2–4 displayed potent antimicrobial activity against the Gram-positive bacterium Kocuria rhizohpila and the plant pathogenic fungus

• examined in antimicrobial and cytotoxicity assays (Table 3). Pseudosporamide (1) was not active against all microorganisms tested in this study. Pseudosporamicin 2–4 were selectively active against the Gram-positive bacterium Kocuria rhizophila and the filamentous fungus Glomerella cingulate, but were

• inactive against Staphylococcus aureus, Escherichia coli, Rhizobium radiobacter, and Candida albicans. The antimicrobial potency of 2 and 3 were similar, implying that the acyl side chain at C13 of compound 2 had no influence on the activity. In addition, compounds 1–4 showed moderate cytotoxicity against

Fabclavine diversity in Xenorhabdus bacteria

• Sebastian L. Wenski,
• Harun Cimen,
• Natalie Berghaus,
• Sebastian W. Fuchs,
• Selcuk Hazir and
• Helge B. Bode

Beilstein J. Org. Chem. 2020, 16, 956–965, doi:10.3762/bjoc.16.84

• ), such as daptomycin, vancomycin, or erythromycin, have already been shown to be potent antibiotics [2][3][4]. Consequently, research in the field of novel SMs with antimicrobial activity is vital to provide new avenues to new antiinfective drugs or lead compounds. Beside traditional sources such as

A systematic review on silica-, carbon-, and magnetic materials-supported copper species as efficient heterogeneous nanocatalysts in “click” reactions

• Pezhman Shiri and
• Jasem Aboonajmi

Beilstein J. Org. Chem. 2020, 16, 551–586, doi:10.3762/bjoc.16.52

• catalysts; Sharpless–Meldal C–N bond-forming reaction; silica/carbon/magnetic materials; Introduction Heterocycles are a class of organic compounds with significant biological activities [1][2][3][4][5][6][7][8][9][10], including antimicrobial [2], antibacterial [3], anti-HIV [4], antiviral [5

• ], antiparkinsonian [6], and anticancer [10] properties. Particularly, triazoles illustrate distinguished moieties well distributed in natural products with biological properties [2][3][4][9][10], including antimicrobial [2], antibacterial [3], antifungal [3], anti-HIV [4], and anticancer [10] activities. One of the

Regio- and stereoselective synthesis of new ensembles of diversely functionalized 1,3-thiaselenol-2-ylmethyl selenides by a double rearrangement reaction

• Svetlana V. Amosova,
• Andrey A. Filippov,
• Nataliya A. Makhaeva,
• Alexander I. Albanov and
• Vladimir A. Potapov

Beilstein J. Org. Chem. 2020, 16, 515–523, doi:10.3762/bjoc.16.47

• activity based on affordable and environmentally friendly materials is another important trend in organoselenium chemistry [17]. Reviews on the biological activity of organoselenium compounds reported examples exhibiting high antitumor, antiviral, antimicrobial, and neuroprotective activities [12][18][19

Two antibacterial and PPARα/γ-agonistic unsaturated keto fatty acids from a coral-associated actinomycete of the genus Micrococcus

• Amit Raj Sharma,
• Enjuro Harunari,
• Naoya Oku,
• Nobuyasu Matsuura,
• Agus Trianto and
• Yasuhiro Igarashi

Beilstein J. Org. Chem. 2020, 16, 297–304, doi:10.3762/bjoc.16.29

• antimicrobial metabolites from an actinomycete [36] and a basidiomycete fungus [37]. In addition, long-chain saturated fatty acids possessing a keto group were detected in the solvent extract of Legionella by GC–MS analysis [38]. Fatty acid components in fresh water-derived Micrococcus species were

• interesting contrast. No appreciable antimicrobial activity was observed for both compounds against bacterial strains of Micrococcus luteus ATCC9341, Staphylococcus aureus FDA209P JC-1, and Escherichia coli NIHJ JC-2 and yeast strains of Candida albicans NBRC0197 and Saccharomyces cerevisiae S100, nor

• system simulations were performed using the freeware nmrpeak.exe [19]. Antimicrobial assay Antimicrobial assays were carried out in a similar manner as described in [18]. The antimicrobial activity was evaluated by the liquid microculture method using round-bottomed 96-well microtiter plates against five

Copper-catalyzed enantioselective conjugate addition of organometallic reagents to challenging Michael acceptors

• Delphine Pichon,
• Jennifer Morvan,
• Christophe Crévisy and
• Marc Mauduit

Beilstein J. Org. Chem. 2020, 16, 212–232, doi:10.3762/bjoc.16.24

• ratios were obtained (51:49 to 97:3). Of note, chiral phosphines were also screened, but without any improvement of selectivity. Furthermore, this methodology was then efficiently applied to the total synthesis of several bisabolane sesquiterpenes, which exhibited anticancer and antimicrobial activities

The reaction of arylmethyl isocyanides and arylmethylamines with xanthate esters: a facile and unexpected synthesis of carbamothioates

• Narasimhamurthy Rajeev,
• Toreshettahally R. Swaroop,
• Ahmad I. Alrawashdeh,
• Shofiur Rahman,
• Abdullah Alodhayb,
• Seegehalli M. Anil,
• Kuppalli R. Kiran,
• Chandra,
• Paris E. Georghiou,
• Kanchugarakoppal S. Rangappa and
• Maralinganadoddi P. Sadashiva

Beilstein J. Org. Chem. 2020, 16, 159–167, doi:10.3762/bjoc.16.18

• ) have been reported to have antimicrobial [1], antifungal (e.g., tolnaftate and tolciclate) [2], antimycobacterial [3], human leucocyte elastase inhibitory [4], TRPV1 antagonistic [5], and PPARα1γ dual antagonistic [6] properties, and also act as intermediates in the syntheses of HIV-1 integrase ligands

The interaction between cucurbit[8]uril and baicalein and the effect on baicalein properties

• Xiaodong Zhang,
• Jun Xie,
• Zhiling Xu,
• Zhu Tao and
• Qianjun Zhang

Beilstein J. Org. Chem. 2020, 16, 71–77, doi:10.3762/bjoc.16.9

• ; inclusion complex; properties; Introduction Baicalein (5,6,7-trihydroxyflavonoid) has a molecular formula of C15H10O5 (BALE, Figure 1) and is a natural flavonoid found in the roots of Scutellaria baicalensis Georgi [1]. The compound displays pharmacological activity such as antimicrobial, anti-inflammatory

Light-controllable dithienylethene-modified cyclic peptides: photoswitching the in vivo toxicity in zebrafish embryos

• Sergii Afonin,
• Oleg Babii,
• Aline Reuter,
• Volker Middel,
• Masanari Takamiya,
• Uwe Strähle,
• Igor V. Komarov and
• Anne S. Ulrich

Beilstein J. Org. Chem. 2020, 16, 39–49, doi:10.3762/bjoc.16.6

• photoswitch into the backbone of gramicidin S (1, GS), which is an intrinsically biostable cyclic peptide, as exemplified by one of our first prototypes compound 2 (Figure 1C). This natural antimicrobial agent has an amphipathic structure, whose functional mechanism is attributed to the permeabilization of

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

• identified as a major mechanism contributing to antimicrobial resistance of Gram-negative pathogenic bacteria. Inhibition of the corresponding enzymatic steps, specifically the transfer of 4-amino-4-deoxy-ʟ-arabinose, would thus restore the activity of cationic antimicrobial peptides and several

• antimicrobial drugs. C-glycosidically-linked phospholipid derivatives of 4-amino-4-deoxy-ʟ-arabinose have been prepared as hydrolytically stable and chain-shortened analogues of the native undecaprenyl donor. The C-phosphonate unit was installed via a Wittig reaction of benzyl-protected 1,5-arabinonic acid

• 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

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

• formation of Staphylococcus aureus DSM1104. The lack of toxicity toward the studied microorganism and cell lines of pigmentosin B (2), as well as the antimicrobial effect of pigmentosin A (1), made them good candidates for further development for use in combination therapy of infections involving biofilm

• possess nonselective activities in biological systems and exhibit antimicrobial [28], cytotoxic [29], antimycobacterial [30], and antimalarial [31] effects. Pigmentosin A (1) and its new derivative pigmentosin B (2) exhibited weak activity against B. subtilis, with MIC values of 12.5 and 100 μg/mL

• than 250 μg/mL. Based on the evidence that the cells of S. aureus could still grow by more than 80% of the growth control at the lowest concentration where the biofilm formation was interrupted, both pigmentosins 1 and 2 showed antibiofilm effects independently from their antimicrobial activity

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

• ; mutasynthesis; NRPS; peptide synthesis; Introduction Resistance to antibiotics is currently a major threat to public health. Especially Gram-negative bacterial pathogens are of concern, due to their widespread development of resistance mechanisms. To address this general antimicrobial resistance problem, new

Facile regiodivergent synthesis of spiro pyrrole-substituted pseudothiohydantoins and thiohydantoins via reaction of [e]-fused 1H-pyrrole-2,3-diones with thiourea

• Aleksandr I. Kobelev,
• Nikita A. Tretyakov,
• Ekaterina E. Stepanova,
• Maksim V. Dmitriev,
• Michael Rubin and
• Andrey N. Maslivets

Beilstein J. Org. Chem. 2019, 15, 2864–2871, doi:10.3762/bjoc.15.280

• reflux. Reaction of FPDs 1 with 1,3-diphenylthiourea. Supporting Information Supporting Information File 546: Experimental details, copies of 1H and 13C NMR spectra, X-ray crystallographic details, references to antimicrobial assay results, and a detailed revision of previously published structures