Fluorocyclisation via I(I)/I(III) catalysis: a concise route to fluorinated oxazolines

• Felix Scheidt,
• Christian Thiehoff,
• Gülay Yilmaz,
• Stephanie Meyer,
• Constantin G. Daniliuc,
• Gerald Kehr and
• Ryan Gilmour

Beilstein J. Org. Chem. 2018, 14, 1021–1027, doi:10.3762/bjoc.14.88

• siderophore antibiotic D-fluviabactin, the cytotoxic agent westiellamide, the antifungal macrodiolide leupyrrin A1 and the antitumour compound BE-70016 (Figure 1). In addition, synthetic polymers based on the 2-oxazoline building block constitute versatile platforms for a range of biomedical applications

Recent advances in synthetic approaches for medicinal chemistry of C-nucleosides

• Kartik Temburnikar and
• Katherine L. Seley-Radtke

Beilstein J. Org. Chem. 2018, 14, 772–785, doi:10.3762/bjoc.14.65

• resultant compounds are called carbocyclic C-nucleosides. Examples of natural and synthetic C-nucleosides. Pseudouridine and formcycin are among several naturally occurring C-nucleosides that are being studied for their role in RNA biology and antibiotic properties respectively. In the recent past

Continuous multistep synthesis of 2-(azidomethyl)oxazoles

• Thaís A. Rossa,
• Nícolas S. Suveges,
• Marcus M. Sá,
• David Cantillo and
• C. Oliver Kappe

Beilstein J. Org. Chem. 2018, 14, 506–514, doi:10.3762/bjoc.14.36

• antibiotic or antimicrobial properties such as pimprinine [4] or phenoxan [5] (Figure 1a). Also many synthetic active pharmaceutical ingredients (API) contain the oxazole as an active moiety [1][2][3]. Oxaprozin, for example, is an important non-narcotic, non-steroidal anti-inflammatory drug [6][7

• ]. Sulfamoxole is a broad-spectrum antibiotic for the treatment of bacterial infections (Figure 1b) [8]. In addition, ongoing studies show the potential of amino and amido-oxazoles to act as fluorescent dipeptidomimetics (Figure 1c) [9]. Due to their diene character, oxazoles find also use as intermediates in

Aminosugar-based immunomodulator lipid A: synthetic approaches

• Alla Zamyatina

Beilstein J. Org. Chem. 2018, 14, 25–53, doi:10.3762/bjoc.14.3

Binding abilities of polyaminocyclodextrins: polarimetric investigations and biological assays

• Marco Russo,
• Daniele La Corte,
• Annalisa Pisciotta,
• Serena Riela,
• Rosa Alduina and
• Paolo Lo Meo

Beilstein J. Org. Chem. 2017, 13, 2751–2763, doi:10.3762/bjoc.13.271

• control experiments [58]. It is worth mentioning here that bacteria have different ways to interact with extracellular DNA. In some cases they can naturally internalize and integrate exogenous DNA (natural competence) and this can result in the acquisition of new genetic traits (e.g., antibiotic

• maintenance by pathogenic bacteria, such as P. aeruginosa and S. aureus [60][61][62]. In addition, eDNA with its negative charge can sequester cationic antibiotics contributing to antibiotic resistance; thus, removing eDNA from the biofilm matrix can weaken the biofilm and can raise its susceptibility to

• antibiotics. The fact that these cyclodextrin derivatives might be loaded with an antibiotic allows speculating that a possible antibiotic–CD complex could target the pathogen and in the meanwhile to bind and sequester extracellular DNA, inhibiting its role in vivo. Finally, a particular mention is deserved

An efficient synthesis of 1,6-anhydro-N-acetylmuramic acid from N-acetylglucosamine

• Matthew B. Calvert,
• Christoph Mayer and
• Alexander Titz

Beilstein J. Org. Chem. 2017, 13, 2631–2636, doi:10.3762/bjoc.13.261

• in only five steps from the cheap starting material N-acetylglucosamine. This efficient synthesis should enable future studies into the importance of 1,6-anhydromuramic acid in bacterial cell wall recycling processes. Keywords: N-acetylmuramic acid; anhydrosugars; antibiotic resistance; bacterial

Consecutive hydrazino-Ugi-azide reactions: synthesis of acylhydrazines bearing 1,5-disubstituted tetrazoles

• Angélica de Fátima S. Barreto,
• Veronica Alves dos Santos and
• Carlos Kleber Z. Andrade

Beilstein J. Org. Chem. 2017, 13, 2596–2602, doi:10.3762/bjoc.13.256

• linatine [24] and the antibiotic negamycin, active against Gram-negative bacteria [25], among others [26]. Furthermore, trisubstituted acylhydrazines were found to serve as tertiary amide bioisosters [27]. Therefore, it is highly desirable to have a method that allows an easy incorporation of hydrazino

Exploring mechanochemistry to turn organic bio-relevant molecules into metal-organic frameworks: a short review

• Vânia André,
• Sílvia Quaresma,
• João Luís Ferreira da Silva and
• M. Teresa Duarte

Beilstein J. Org. Chem. 2017, 13, 2416–2427, doi:10.3762/bjoc.13.239

• using 4-aminosalicylic acid and piracetam. 4-Aminosalicylic acid is an antibiotic that has been used in the treatment of tuberculosis, inflammatory bowel diseases, namely distal ulcerative colitis [125][126] and Crohn’s disease [127], while piracetam is a nootropic drug used to improve cognitive

Sulfation and amidinohydrolysis in the biosynthesis of giant linear polyenes

• Hui Hong,
• Markiyan Samborskyy,
• Katsiaryna Usachova,
• Katharina Schnatz and
• Peter F. Leadlay

Beilstein J. Org. Chem. 2017, 13, 2408–2415, doi:10.3762/bjoc.13.238

• in a genome-led approach to the uncovering of novel enzymology in the biosynthetic pathways to antibiotic natural products [23][24][25][26]. Here, we have used in-house whole-genome sequencing to characterise the closely-related gene clusters to the sulfated antifungal linear polyenes clethramycin

• . Sulfonation has been suggested as a novel approach to block the development of antibiotic resistance [33][34] while the discovery of the sulfated metabolite FR901379 was a critical breakthrough in the successful clinical development of micafungin to combat systemic fungal infections [12]. HPLC–UV–MS analysis

Conjugated nitrosoalkenes as Michael acceptors in carbon–carbon bond forming reactions: a review and perspective

• Yaroslav D. Boyko,
• Valentin S. Dorokhov,
• Alexey Yu. Sukhorukov and
• Sema L. Ioffe

Beilstein J. Org. Chem. 2017, 13, 2214–2234, doi:10.3762/bjoc.13.220

• . Gilchrist [70] employed oximinoalkylation of pyrrole as the initial stage in the synthesis of 1,2-dihydropyrrolizinone antibiotic 82 [71][72][73] (Scheme 29). The addition of ethyl 2-nitrosoacrylate (generated from ethyl bromopyruvate oxime) to pyrrole under basic conditions afforded product 67a in 61

A new member of the fusaricidin family – structure elucidation and synthesis of fusaricidin E

• Marcel Reimann,
• Louis P. Sandjo,
• Luis Antelo,
• Eckhard Thines,
• Isabella Siepe and
• Till Opatz

Beilstein J. Org. Chem. 2017, 13, 1430–1438, doi:10.3762/bjoc.13.140

• chain is of key importance for the antibiotic activity of the fusaricidins and their selective inhibition of bacterial cells due to the interaction with phospholipid cell membranes [1]. Genetic analysis of the producing organisms suggests that the biosynthesis of this essential part of the fusaricidins

Sustainable synthesis of 3-substituted phthalides via a catalytic one-pot cascade strategy from 2-formylbenzoic acid with β-keto acids in glycerol

• Lina Jia and
• Fuzhong Han

Beilstein J. Org. Chem. 2017, 13, 1425–1429, doi:10.3762/bjoc.13.139

• [3][4][5], exhibit a broad spectrum of pharmacological activity, such as antibacterial, anti-HIV, antifungal, antibiotic, antitumor and immunosuppressive effects [6][7][8][9][10]. In addition, the one-pot cascade transformation has proven to be the key step in organic syntheses because of its broad

Synthesis of the heterocyclic core of the D-series GE2270

• Christophe Berini,
• Thibaut Martin,
• Pierrik Lassalas,
• Francis Marsais,
• Christine Baudequin and
• Christophe Hoarau

Beilstein J. Org. Chem. 2017, 13, 1407–1412, doi:10.3762/bjoc.13.137

• as readily available starting material. Keywords: antibiotic; bromination; BSC; C–H arylation; cross-coupling; Hantzsch synthesis; thiopeptide; Introduction Thiopeptide antibiotics are a class of peptide-derived macrocycles which contain many thiazole and thiazoline units, with almost 90 structures

• heterocyclic core of the D-series thiopeptide antibiotic GE2270 was prepared. The synthetic strategy that combines direct C–H arylation, Borylation Suzuki–Miyaura cross-coupling (BSC) and Hantzsch thiazole synthesis methods proved to be highly effective regarding the fair 22% yield over 7 synthetic steps from

Total synthesis of elansolids B1 and B2

• Liang-Liang Wang and
• Andreas Kirschning

Beilstein J. Org. Chem. 2017, 13, 1280–1287, doi:10.3762/bjoc.13.124

• bacterium Chitinophaga sancti. They show antibacterial activity against Gram-positive bacteria. A second generation total synthesis of the antibiotic elansolid B1 (2) and the first synthesis of elansolid B2 (3) are reported. In contrast to previous work, the (Z,E,Z)-triene at C10–C15 was assembled by using

• Flexibacter spec.) (Figure 1) [1][2]. Elansolid A2 (1*), an atropisomer of elansolid A1 (1), showed antibiotic activity against Gram-positive bacteria in the range of 0.2 to 64 µg/mL and cytotoxicity against L929 mouse fibroblast cells with an IC50 value of 12 µg/mL. Besides these two macrocylic members also

• data determined for both synthetic products were identical with those of authentic samples of elansolid B1 (2) and elansolid B2 (3) (copies of spectra, see Supporting Information File 1). Conclusion In conclusion, we describe an improved second generation synthesis of the highly active antibiotic

Glyco-gold nanoparticles: synthesis and applications

• Federica Compostella,
• Olimpia Pitirollo,
• Alessandro Silvestri and
• Laura Polito

Beilstein J. Org. Chem. 2017, 13, 1008–1021, doi:10.3762/bjoc.13.100

• -antibiotic conjugates, were prepared and resulted able to overcome antibiotic resistance of microbial biofilms, since CA NPs render streptomycin more accessible to biofilms, thereby more available to interact with biofilm bacteria [89]. Similarly, a novel recyclable E.coli-specific killing GAuNP

First total synthesis of kipukasin A

• Chuang Li,
• Haixin Ding,
• Zhizhong Ruan,
• Yirong Zhou and
• Qiang Xiao

Beilstein J. Org. Chem. 2017, 13, 855–862, doi:10.3762/bjoc.13.86

• ) and AZT, etc. [5][6]. Nucleosides and their analogues will continue to play an important role in future drug discovery [7]. In the past decades, exploration of novel naturally occurring marine nucleosides has made expeditious achievements [8][9][10]. Some of them showed promising antibiotic, antiviral

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

• ), artemisinin [2] (antimalarial agent) and α-pinene [3] (antibiotic, anti-inflammatory). Apart from bioactive compounds with applications as drugs/pharmaceuticals [4] or in the nutrition or agricultural sector, isoprenoids of minor structural complexity are used as bulk chemicals or fuel additives [5][6]. To

N-Propargylamines: versatile building blocks in the construction of thiazole cores

• S. Arshadi,
• E. Vessally,
• L. Edjlali,
• R. Hosseinzadeh-Khanmiri and
• E. Ghorbani-Kalhor

Beilstein J. Org. Chem. 2017, 13, 625–638, doi:10.3762/bjoc.13.61

• ], antimicrobial [57][58][59], and specially antibiotic [60][61][62][63][64] agents. Despite their great relevance in drug design, only very few synthetic methods towards these compounds have been reported to date [44]. N-Propargylamines are one of the most specific class of alkynes having diverse reaction

Posttranslational isoprenylation of tryptophan in bacteria

• Masahiro Okada,
• Tomotoshi Sugita and
• Ikuro Abe

Beilstein J. Org. Chem. 2017, 13, 338–346, doi:10.3762/bjoc.13.37

• at a high population cell density in B. subtilis [19][20]. In addition, the ComX pheromone promotes the production of surfactin A, a cyclic lipopeptide with antibiotic and biological surfactant activities (Figure 2A) [21][22]. Furthermore, the ComXnatto pheromone from B. subtilis subsp. natto

Synthesis of acylhydrazino-peptomers, a new class of peptidomimetics, by consecutive Ugi and hydrazino-Ugi reactions

• Angélica de Fátima S. Barreto,
• Veronica Alves dos Santos and
• Carlos Kleber Z. Andrade

Beilstein J. Org. Chem. 2016, 12, 2865–2872, doi:10.3762/bjoc.12.285

• -hydrazino acid moiety, e.g., the vitamin B6 antagonist linatine and the antibiotic negamycin (Figure 3). In the early 1970s, the first attempts to peptide modifications by hydrazino acids generated bioactive pseudopeptides [39]. Analogously to azapeptides, these compounds possess a conformational constraint

Biochemical and structural characterisation of the second oxidative crosslinking step during the biosynthesis of the glycopeptide antibiotic A47934

• Veronika Ulrich,
• Clara Brieke and
• Max J. Cryle

Beilstein J. Org. Chem. 2016, 12, 2849–2864, doi:10.3762/bjoc.12.284

• homologues can display significantly different catalytic propensities despite their overall similarities. Keywords: crystal structure; cytochrome P450; glycopeptide antibiotic; peptide; phenolic coupling; Introduction The glycopeptide antibiotics (GPAs) are a series of highly modified heptapeptide natural

Enduracididine, a rare amino acid component of peptide antibiotics: Natural products and synthesis

• Darcy J. Atkinson,
• Briar J. Naysmith,
• Daniel P. Furkert and
• Margaret A. Brimble

Beilstein J. Org. Chem. 2016, 12, 2325–2342, doi:10.3762/bjoc.12.226

• 10.3762/bjoc.12.226 Abstract Rising resistance to current clinical antibacterial agents is an imminent threat to global public health and highlights the demand for new lead compounds for drug discovery. One such potential lead compound, the peptide antibiotic teixobactin, was recently isolated from an

• promising antibiotic activity. This review highlights the presence of enduracididine in natural products, its biosynthesis together with a review of analogues of enduracididine. Reported synthetic approaches to the cyclic guanidine structure of enduracididine are discussed, illustrating the challenges

• fungicidicus [18]. Enduracidin A (7) and B (8) are depsipeptides with the same composition of seventeen amino acids, sixteen of which make up the cyclic core [11][13][19] and are structurally related to the non-enduracididine containing antibiotic, ramoplanin [19]. The enduracidins are active against Gram

The direct oxidative diene cyclization and related reactions in natural product synthesis

• Juliane Adrian,
• Leona J. Gross and
• Christian B. W. Stark

Beilstein J. Org. Chem. 2016, 12, 2104–2123, doi:10.3762/bjoc.12.200

• coupling [53][54]. The oxidative cyclization diastereoselectively led to the THF diol 13 in 88% yield from which neodysiherbaine A (14) was obtained in a further three steps. Ionomycin Ionomycin (19), an ionophore antibiotic isolated from Streptomyces conglobatus in 1978 [55][56][57], has a high affinity

• monensin A, another well-known ionophore antibiotic, applying an oxidative cyclization approach using potassium permanganate [64]. Amphidinolide F Amphidinolide F (24) is a marine natural product isolated from the dinoflagellate Amphidinium sp. in 1991 [65]. The macrocyclic core of these highly cytotoxic

Synthesis of the C8’-epimeric thymine pyranosyl amino acid core of amipurimycin

• Pramod R. Markad,
• Navanath Kumbhar and
• Dilip D. Dhavale

Beilstein J. Org. Chem. 2016, 12, 1765–1771, doi:10.3762/bjoc.12.165

• this regard are in progress. Antifungal antibiotic amipurimycin (1). Conformational analysis of 13 and 14. Geometrically optimized conformation of 12 and 13 respectively by DFT study. Retrosynthesis of 2. Synthesis of 1,3-anhydrosugar 12 and 13. Formation of 2,7-dioxabicyclo[3.2.1]octane 12/13

TMSBr-mediated solvent- and work-up-free synthesis of α-2-deoxyglycosides from glycals

• Mei-Yuan Hsu,
• Yi-Pei Liu,
• Sarah Lam,
• Su-Ching Lin and
• Cheng-Chung Wang

Beilstein J. Org. Chem. 2016, 12, 1758–1764, doi:10.3762/bjoc.12.164

• ); Introduction Deoxyglycosides are essential moieties of numerous bioactive natural products, and are prevalent subunits in antitumor and antibiotic agents [1][2][3]. Furthermore, 2-deoxy- and 2,6-dideoxyglycosides are crucial components for the pharmacology and bioactivity of many biologically active compounds