New variochelins from soil-isolated Variovorax sp. H002

• Jabal Rahmat Haedar,
• Aya Yoshimura and
• Toshiyuki Wakimoto

Beilstein J. Org. Chem. 2024, 20, 692–700, doi:10.3762/bjoc.20.63

• fatty acyl groups. Furthermore, the variochelin biosynthetic gene cluster was identified through draft genome sequencing and gene knockout experiments. Compounds 1–5 exhibited antimicrobial activities against Gram-negative bacteria, including several soil-isolated plant pathogens. Keywords

• variochelins [20]. Biological activity The antimicrobial activities of 1–5 were evaluated against several Gram-negative and Gram-positive bacteria (Table 1). As a result, 1–5 inhibited the growth of the Gram-negative bacteria Escherichia coli and Burkholderia multivorans, but lacked activity against Bacillus

Pseudallenes A and B, new sulfur-containing ovalicin sesquiterpenoid derivatives with antimicrobial activity from the deep-sea cold seep sediment-derived fungus Pseudallescheria boydii CS-793

• Zhen Ying,
• Xiao-Ming Li,
• Sui-Qun Yang,
• Hong-Lei Li,
• Xin Li,
• Bin-Gui Wang and
• Ling-Hong Meng

Beilstein J. Org. Chem. 2024, 20, 470–478, doi:10.3762/bjoc.20.42

• antimicrobial activities [3][4]. As part of our continuing search for bioactive metabolites from deep-sea-derived fungi [3][4][5][6], the fungal strain Pseudallescheria boydii CS-793, which was obtained from sediments collected at the deep-sea cold seep area in the Northeast of the South China Sea, attracted

• pathway for compounds 1–5. 1H (500 MHz) and 13C NMR (125 MHz) data for compounds 1–3. Antimicrobial activities of compounds 1–3 (MIC).a Supporting Information Supporting Information File 5: Selected 1D and 2D NMR, and HRESIMS spectra of compounds 1 and 2, and 1D NMR spectra of compounds 3–5. Supporting

Development of a chemical scaffold for inhibiting nonribosomal peptide synthetases in live bacterial cells

• Fumihiro Ishikawa,
• Sho Konno,
• Hideaki Kakeya and
• Genzoh Tanabe

Beilstein J. Org. Chem. 2024, 20, 445–451, doi:10.3762/bjoc.20.39

• activities against the A-domain of MbtA, a component of mycobactin synthetase and antimicrobial activities against M. tuberculosis [7]. In addition, aminoacyl (AA)-AMS has been designed to inhibit the amino acid-activating A-domains in NRPSs and has been found to be a tight-binding inhibitor (Figure 2b) [8

Synthesis and biological evaluation of Argemone mexicana-inspired antimicrobials

• Jessica Villegas,
• Bryce C. Ball,
• Katelyn M. Shouse,
• Caleb W. VanArragon,
• Ashley N. Wasserman,
• Hannah E. Bhakta,
• Allen G. Oliver,
• Danielle A. Orozco-Nunnelly and
• Jeffrey M. Pruet

Beilstein J. Org. Chem. 2023, 19, 1511–1524, doi:10.3762/bjoc.19.108

• ) to evaluate their antimicrobial activities compared to original berberine, via a Kirby–Bauer test with 0.12 mg of the compound tested per disc (Table 1). It was immediately apparent that the polar substituent at position-13 for variants B2, B4, and B6 effectively abolished any activity. This result

Synthesis of ether lipids: natural compounds and analogues

• Marco Antônio G. B. Gomes,
• Alicia Bauduin,
• Chloé Le Roux,
• Romain Fouinneteau,
• Wilfried Berthe,
• Mathieu Berchel,
• Hélène Couthon and
• Paul-Alain Jaffrès

Beilstein J. Org. Chem. 2023, 19, 1299–1369, doi:10.3762/bjoc.19.96

Cyclometalated iridium complexes-catalyzed acceptorless dehydrogenative coupling reaction: construction of quinoline derivatives and evaluation of their antimicrobial activities

• Hongling Shui,
• Yuhong Zhong,
• Renshi Luo,
• Zhanyi Zhang,
• Jiuzhong Huang,
• Ping Yang and
• Nianhua Luo

Beilstein J. Org. Chem. 2022, 18, 1507–1517, doi:10.3762/bjoc.18.159

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

• formation from tetrazolo[1,5-a]quinoxalines 1 is still limited. Triazole-linked N-heterocycles like pyridotriazoles and quinolinotriazoles exert a variety of favorable biological properties like anticancer and antimicrobial activities as well as protein kinase inhibition [10][13][14][15]. Moreover, a vast

Cholyl 1,3,4-oxadiazole hybrid compounds: design, synthesis and antimicrobial assessment

• Anas J. Rasras,
• Mohamed El-Naggar,
• Nesreen A. Safwat and
• Raed A. Al-Qawasmeh

Beilstein J. Org. Chem. 2022, 18, 631–638, doi:10.3762/bjoc.18.63

• , 4p and 4c, respectively. Besides, the order of antifungal activity against the pathogenic yeast Candida albicans was 4g, 4i, 4q, 4j, 4o, 4p, 4m, 4k, 4s, 4t, 4n, 4v, 4d, 4e, 4h, 4l, 4c and 4r, respectively (Table 1). Likewise, no antimicrobial activities could be detected for compound 4f under these

• was confirmed by the MIC values measured by the broth microdilution method by recording the lowest concentration that showed inhibition of microbial growth (Table 2). The results of the determined MIC values showed the same trend of the antimicrobial activities explored by determination of the

• chemical library based on the hybridization of cholic acid with the heterocyclic moiety 1,3,4-oxadizole was synthesized. All new compounds were unambiguously characterized by various spectroscopic techniques. The newly synthesized compounds were assessed in vitro for their antimicrobial activities

Sesquiterpenes from the soil-derived fungus Trichoderma citrinoviride PSU-SPSF346

• Wiriya Yaosanit,
• Vatcharin Rukachaisirikul,
• Souwalak Phongpaichit,
• Sita Preedanon and
• Jariya Sakayaroj

Beilstein J. Org. Chem. 2022, 18, 479–485, doi:10.3762/bjoc.18.50

• Swamp Forest, Narathiwat Province, Thailand. The crude mycelial extract of T. citrinoviride PSU-SPSF346 displayed antimicrobial activities against Staphylococcus aureus, methicillin-resistant S. aureus, and Cryptococcus neoformans ATCC90113 with MIC values of 128, 200 and 64 μg/mL, respectively. Herein

Glycosylated coumarins, flavonoids, lignans and phenylpropanoids from Wikstroemia nutans and their biological activities

• Meifang Wu,
• Xiangdong Su,
• Yichuang Wu,
• Yuanjing Luo,
• Ying Guo and
• Yongbo Xue

Beilstein J. Org. Chem. 2022, 18, 200–207, doi:10.3762/bjoc.18.23

• antimicrobial activities [27], the antimicrobial activity of compounds 1–4 was also evaluated against the bacteria Escherichia coli, Staphylococcus aureus subsp. aureus, Salmonella enterica subsp. enterica, and Pseudomonas aeruginosa. However, all of them were found to be devoid of inhibitory activity (MIC >250

• antimicrobial activities. This is the first report of the isolation of coumarins, flavonoids, lignans and phenylpropanoid glycosides from W. nutans, while compounds 1–3, 8, and 11 was encountered from the genus Wikstroemia for the first time. Our work will enrich the chemistry and structure diversity of natural

• concentration in the supernatants with Griess reagent as described previously [28]. Antimicrobial assay Compounds 1–4 were evaluated for their antimicrobial activities against Escherichia coli, Staphylococcus aureus subsp. aureus, Salmonella enterica subsp. enterica, and Pseudomonas aeruginosa. Antimicrobial

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

• °C for 1 h (Table 2). Spectroscopic data of the racemic products were in full agreement with published data from former total syntheses [24][25][36][38][42][43][44][45]. Screening Bisbenzylisoquinoline alkaloids like tetrandrine and cepharanthine exhibit a broad spectrum of antimicrobial activities

Isolation and characterization of new phenolic siderophores with antimicrobial properties from Pseudomonas sp. UIAU-6B

• Emmanuel T. Oluwabusola,
• Olusoji O. Adebisi,
• Fernando Reyes,
• Kojo S. Acquah,
• Mercedes De La Cruz,
• Larry L. Mweetwa,
• Joy E. Rajakulendran,
• Digby F. Warner,
• Deng Hai,
• Rainer Ebel and
• Marcel Jaspars

Beilstein J. Org. Chem. 2021, 17, 2390–2398, doi:10.3762/bjoc.17.156

• ][37], together with their antimicrobial activities against vancomycin-sensitive Enterococcus faecium VS144754 and Mycobacterium tuberculosis strain H37Rv. A plausible biosynthetic hypothesis is proposed towards the new compounds 1–5. Results and Discussion The preliminary LC–MS analysis of the

• unit [40]. Biological evaluation Compounds 1–7 were evaluated for their antimicrobial activities against methicillin-resistant Staphylococcus aureus (MRSA), methicillin-sensitive Staphylococcus aureus (MSSA), Escherichia coli, Acinetobacter Bahmani, vancomycin-resistant E. faecium VanA15167, vancomycin

Analogs of the carotane antibiotic fulvoferruginin from submerged cultures of a Thai Marasmius sp.

• Birthe Sandargo,
• Leon Kaysan,
• Rémy B. Teponno,
• Christian Richter,
• Benjarong Thongbai,
• Frank Surup and
• Marc Stadler

Beilstein J. Org. Chem. 2021, 17, 1385–1391, doi:10.3762/bjoc.17.97

• fulvoferruginins A–F (1–6), aside from the known antifungal activity of fulvoferruginin (1), no other antimicrobial activities were observed (Table S2 in Supporting Information File 1). All metabolites were also tested against the murine fibroblast cell line L929 and the cervix carcinoma cell line KB3.1. While all

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

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

Isolation of fungi using the diffusion chamber device FIND technology

• Benjamin Libor,
• Henrik Harms,
• Stefan Kehraus,
• Ekaterina Egereva,
• Max Crüsemann and
• Gabriele M. König

Beilstein J. Org. Chem. 2019, 15, 2191–2203, doi:10.3762/bjoc.15.216

• antimicrobial activities against Gram-negative and Gram-positive bacteria, an ascomycete, a basidiomycete and a zygomycete, i.e., Escherichia coli, Bacillus megaterium, Eurotium rubrum, Microbotryum violaceum and Mycotypha microspora. Ethyl acetate extracts of C. rosea, I. europaea grown on BM medium and of the

An overview of the cycloaddition chemistry of fulvenes and emerging applications

• Ellen Swan,
• Kirsten Platts and
• Anton Blencowe

Beilstein J. Org. Chem. 2019, 15, 2113–2132, doi:10.3762/bjoc.15.209

•  21) [105][237]. ROMP of the monomers, followed by deprotection yielded facially amphiphilic polynorbornenes that displayed lipid membrane disruption and antimicrobial activities [237][238]. The facially amphiphilic polynorbornenes with pendent ammonium groups were found to disrupt negatively charged

Towards the preparation of synthetic outer membrane vesicle models with micromolar affinity to wheat germ agglutinin using a dialkyl thioglycoside

• Dimitri Fayolle,
• Nathalie Berthet,
• Bastien Doumeche,
• Olivier Renaudet,
• Peter Strazewski and
• Michele Fiore

Beilstein J. Org. Chem. 2019, 15, 937–946, doi:10.3762/bjoc.15.90

• Fisher reaction between pyranoses and fatty alcohols of different lengths [8][9]. Alkyl thioglycosides are known for their properties as co-surfactants [10] and present interesting antimicrobial activities [11], acting as glycosidase inhibitors and being resistant towards glycoside hydrolases [12][13

Aminomethylation/hydrogenolysis as an alternative to direct methylation of metalated isoquinolines – a novel total synthesis of the alkaloid 7-hydroxy-6-methoxy-1-methylisoquinoline

• Benedikt C. Melzer,
• Jan G. Felber and
• Franz Bracher

Beilstein J. Org. Chem. 2018, 14, 130–134, doi:10.3762/bjoc.14.8

• considerable relevance in drug development, since it is found in both complex [1] and “simple” alkaloids (variously substituted derivatives of the native isoquinoline) isolated from different plants [2], and antiviral and antimicrobial activities have been found for numerous isoquinoline alkaloids [3]. Further

Diosgenyl 2-amino-2-deoxy-β-D-galactopyranoside: synthesis, derivatives and antimicrobial activity

• Henryk Myszka,
• Patrycja Sokołowska,
• Agnieszka Cieślińska,
• Andrzej Nowacki,
• Maciej Jaśkiewicz,
• Wojciech Kamysz and
• Beata Liberek

Beilstein J. Org. Chem. 2017, 13, 2310–2315, doi:10.3762/bjoc.13.227

• the obtained compounds are active against Gram-positive bacteria and Candida type fungi. Keywords: antimicrobial activities; D-galactosamine; diosgenin; glycosylation; saponin; tetrachlorophthalimido derivatives; Introduction Saponins are steroid or triterpenoid glycosides found in various plants [1

Synthesis and evaluation of anti-oxidant and cytotoxic activities of novel 10-undecenoic acid methyl ester based lipoconjugates of phenolic acids

• Naganna Narra,
• Shiva Shanker Kaki,
• Rachapudi Badari Narayana Prasad,
• Sunil Misra,
• Koude Dhevendar,
• Venkateshwarlu Kontham and
• Padmaja V. Korlipara

Beilstein J. Org. Chem. 2017, 13, 26–32, doi:10.3762/bjoc.13.4

• transesterified with different oils or triglycerides [6]. Apart from these structured phenolipids, different fatty acids were esterified with phenolic compounds to produce novel esters which were evaluated for anti-oxidant and antimicrobial activities [7][8]. However, there are very few reports where the phenolic

Varioloid A, a new indolyl-6,10b-dihydro-5aH-[1]benzofuro[2,3-b]indole derivative from the marine alga-derived endophytic fungus Paecilomyces variotii EN-291

• Peng Zhang,
• Xiao-Ming Li,
• Xin-Xin Mao,
• Attila Mándi,
• Tibor Kurtán and
• Bin-Gui Wang

Beilstein J. Org. Chem. 2016, 12, 2012–2018, doi:10.3762/bjoc.12.188

• search for structurally unique and bioactive secondary metabolites from marine fungi, especially from marine alga-derived fungi [6][7][8], we discovered evident DPPH (1,1-diphenyl-2-picrylhydrazyl) radical scavenging activity and diverse antimicrobial activities in the EtOAc extract from Paecilomyces

• variotii EN-291, an endophytic fungus isolated from the red alga Grateloupia turuturu. The investigation of the chemical constituents of this fungal strain had been performed and as a result, three new oxepine-containing alkaloids with antimicrobial activities [9][10], two new butenolide derivatives with

Muraymycin nucleoside-peptide antibiotics: uridine-derived natural products as lead structures for the development of novel antibacterial agents

• Daniel Wiegmann,
• Stefan Koppermann,
• Marius Wirth,
• Giuliana Niro,
• Kristin Leyerer and
• Christian Ducho

Beilstein J. Org. Chem. 2016, 12, 769–795, doi:10.3762/bjoc.12.77

• summarised in the following section on SAR studies. Structure–activity relationship studies With various structurally diverse compounds at hand, the stage has been set for SAR studies on muraymycins. The antimicrobial activities found by McDonald et al. introduced muraymycins as a promising subject of study

• = 0.027 μg/mL), which represented activities comparable to those of liposidomycin C (0.05 μg/mL) and mureidomycin A (0.03 μg/mL). As a general trend, higher antimicrobial activities were found for acylated compounds, in particular with longer and functionalised fatty acid side chains. Lin et al. employed

Antibiotics from predatory bacteria

• Juliane Korp,
• María S. Vela Gurovic and
• Markus Nett

Beilstein J. Org. Chem. 2016, 12, 594–607, doi:10.3762/bjoc.12.58

• further characterized by their large genome sizes and their striking potential for the production of structurally diverse natural products with antimicrobial activities [12][30][31][32][33][34][35]. For many years, it has been speculated whether antibiotic biosynthesis is functionally linked to the

• specific enzymatic targets for these natural products [60][68], which are not due to their iron affinity [69]. Myxalamids [70][71][72][73] and myxovirescins [74][75][76][77][78][79] are distinguished by their potent antimicrobial activities. The former are inhibitors of electron transport in the

• found to possess anticancer properties, but they lack antimicrobial activities [126]. In case the siphonazoles should contribute to the predatory behavior of the producing strain, they must exert more subtle effects than those described for myxovirescins and gulmirecins. Efforts to identify secondary

Bromotyrosine-derived alkaloids from the Caribbean sponge Aplysina lacunosa

• Qun Göthel,
• Thanchanok Sirirak and
• Matthias Köck

Beilstein J. Org. Chem. 2015, 11, 2334–2342, doi:10.3762/bjoc.11.254

• -phase HPLC [70:30 H2O (0.1% TFA)/MeCN (0.1% TFA), v/v] to get a mixture of 3 and 15 (3.5 mg) as well as 4 (3.0 mg). Biological activity test The antimicrobial activities of isolated compounds were evaluated against five microorganisms [Gram-positive: Straptococcus aureus (MRSA and MSSA) and Micrococcus