Pentacyclic aromatic heterocycles from Pd-catalyzed annulation of 1,5-diaryl-1,2,3-triazoles

• Kaylen D. Lathrum,
• Emily M. Hanneken,
• Katelyn R. Grzelak and
• James T. Fletcher

Beilstein J. Org. Chem. 2025, 21, 2524–2534, doi:10.3762/bjoc.21.194

• counterparts 13–18. Because fused ring heterocycles are common components of bioactive molecules, a preliminary evaluation of toxicity for this newly defined class of compounds was completed. Antimicrobial potency against Gram-positive bacteria Bacillus subtilis and Staphylococcus epidermidis, Gram-negative

• bacteria Escherichia coli and Klebsiella aerogenes, and yeast Candida albicans and Saccharomyces cerevisiae was determined using minimum inhibitory concentration (MIC) assays [55][56]. As summarized in Table 4, only five of the twenty-four compounds tested displayed an ability to suppress microbial growth

An Fe(II)-catalyzed synthesis of spiro[indoline-3,2'-pyrrolidine] derivatives

• Elizaveta V. Gradova,
• Nikita A. Ozhegov,
• Roman O. Shcherbakov,
• Alexander G. Tkachenko,
• Larisa Y. Nesterova,
• Elena Y. Mendogralo and
• Maxim G. Uchuskin

Beilstein J. Org. Chem. 2025, 21, 2383–2388, doi:10.3762/bjoc.21.183

• microorganisms was determined, including two fungal strains: Candida albicans ATCC 10231, C. albicans C1 – clinical strain, Gram-positive bacteria such as Staphylococcus aureus ATCC 25923, S. aureus ATCC 43300 (MRSA), Mycobacterium smegmatis ATCC 70084, and Gram-negative bacteria including Escherichia coli ATCC

Enantioselective desymmetrization strategy of prochiral 1,3-diols in natural product synthesis

• Lihua Wei,
• Rui Yang,
• Zhifeng Shi and
• Zhiqiang Ma

Beilstein J. Org. Chem. 2025, 21, 1932–1963, doi:10.3762/bjoc.21.151

• -negative bacteria widely distributed in nature [41]. Some species within this genus produce lipases that effectively catalyze the desymmetrization of prochiral diols, which were used in total syntheses. In 2003, an enzymatic asymmetric acylation with PSA, a lipase from Pseudomonas cepacia, was adopted by

• transformation involving acyl-group migration, [4 + 2] cycloaddition and aromatic Pummerer-type reaction, provided chiral spiro compound 59 with the 6/6/5/5/6/6 scaffold, and this intermediate was further elaborated to 60 in six additional steps. Lipases from Pseudomonas genus Pseudomonas is a genus of Gram

Research progress on calixarene/pillararene-based controlled drug release systems

• Liu-Huan Yi,
• Jian Qin,
• Si-Ran Lu,
• Liu-Pan Yang,
• Li-Li Wang and
• Huan Yao

Beilstein J. Org. Chem. 2025, 21, 1757–1785, doi:10.3762/bjoc.21.139

• Gram-negative bacteria. 2.3 Enzyme-responsive controlled release Elevated enzyme levels often mark the microenvironment of many pathological tissues, as well as intracellular and cellular compartments. These enzymes can serve as effective triggers for drug release in stimulus-responsive systems. Owing

Antibiofilm and cytotoxic metabolites from the entomopathogenic fungus Samsoniella aurantia

• Rita Toshe,
• Syeda J. Khalid,
• Blondelle Matio Kemkuignou,
• Esteban Charria-Girón,
• Paul Eckhardt,
• Birthe Sandargo,
• Kunlapat Nuchthien,
• J. Jennifer Luangsa-ard,
• Till Opatz,
• Hedda Schrey,
• Sherif S. Ebada and
• Marc Stadler

Beilstein J. Org. Chem. 2025, 21, 327–339, doi:10.3762/bjoc.21.23

• 2656), Schizosaccharomyces pombe (DSM 70572), Rhodotorula glutinis (DSM 10134), and Wickerhamomyces anomalus (DSM 6766). Additionally, various Gram-positive bacteria such as Staphylococcus aureus (DSM 346), Bacillus subtilis (DSM 10), Mycobacterium smegmatis (ATCC 700084), and Gram-negative bacteria

Discovery of ianthelliformisamines D–G from the sponge Suberea ianthelliformis and the total synthesis of ianthelliformisamine D

• Sasha Hayes,
• Yaoying Lu,
• Bernd H. A. Rehm and
• Rohan A. Davis

Beilstein J. Org. Chem. 2024, 20, 3205–3214, doi:10.3762/bjoc.20.266

• antibacterial agents [20][21]. The absence of polyamine chains in ianthelliformisamines D–G (4–7) could explain the loss of activity seen in our assessment against P. aeruginosa. The synthetic molecule of 7 has been tested by other researchers against Gram-negative bacteria including P. aeruginosa with reported

The Groebke–Blackburn–Bienaymé reaction in its maturity: innovation and improvements since its 21st birthday (2019–2023)

• Cristina Martini,
• Muhammad Idham Darussalam Mardjan and
• Andrea Basso

Beilstein J. Org. Chem. 2024, 20, 1839–1879, doi:10.3762/bjoc.20.162

Discovery of antimicrobial peptides clostrisin and cellulosin from Clostridium: insights into their structures, co-localized biosynthetic gene clusters, and antibiotic activity

• Moisés Alejandro Alejo Hernandez,
• Katia Pamela Villavicencio Sánchez,
• Rosendo Sánchez Morales,
• Karla Georgina Hernández-Magro Gil,
• David Silverio Moreno-Gutiérrez,
• Eddie Guillermo Sanchez-Rueda,
• Yanet Teresa-Cruz,
• Brian Choi,
• Armando Hernández Garcia,
• Alba Romero-Rodríguez,
• Oscar Juárez,
• Siseth Martínez-Caballero,
• Mario Figueroa and
• Corina-Diana Ceapă

Beilstein J. Org. Chem. 2024, 20, 1800–1816, doi:10.3762/bjoc.20.159

• Mycobacterium tuberculosis. The effects of some of these peptides are attributed to their affinity for the lipid II component of Gram-positive bacterial cell walls [25]. Additionally, there have been reports of lantibiotics such as CMB001 displaying activity against resistant Gram-negative bacteria, including

Syntheses and medicinal chemistry of spiro heterocyclic steroids

• Laura L. Romero-Hernández,
• Ana Isabel Ahuja-Casarín,
• Penélope Merino-Montiel,
• Sara Montiel-Smith,
• José Luis Vega-Báez and
• Jesús Sandoval-Ramírez

Beilstein J. Org. Chem. 2024, 20, 1713–1745, doi:10.3762/bjoc.20.152

• , while antibacterial activity was tested against Gram-positive and Gram-negative bacteria. Unfortunately, all compounds exhibited very low activity in these assays. However, the oxathiaphospholanes were evaluated for their antifungal properties against Candida albicans and Saccharomyces cerevisiae, where

Activity assays of NnlA homologs suggest the natural product N-nitroglycine is degraded by diverse bacteria

• Kara A. Strickland,
• Brenda Martinez Rodriguez,
• Ashley A. Holland,
• Shelby Wagner,
• Michelle Luna-Alva,
• David E. Graham and
• Jonathan D. Caranto

Beilstein J. Org. Chem. 2024, 20, 830–840, doi:10.3762/bjoc.20.75

• antibiotic activity towards Gram-negative bacteria. An NNG degrading heme enzyme, called NnlA, has recently been discovered in the genome of Variovorax sp. strain JS1663 (Vs NnlA). Evidence is presented that NnlA and therefore, NNG degradation activity is widespread. To achieve this objective, we

• producers and of NNG is unknown. Additionally, NNG’s physiological function is unknown, but it is toxic to plants, mice, and Gram-negative bacteria [25][26]. While there is no direct evidence of the mechanism of this toxicity, NNG has been shown to competitively inhibit succinate dehydrogenase, a component

• often exhibit antibiotic activity and it has been shown that NNG exhibits antibiotic activity towards Gram-negative bacteria (0.18 to 25 μg/mL) [24]. Moreover, the nitramine functional group has potential to serve as a potent warhead in an antibiotic. For example, a cytochrome P450 homolog, XplA

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

• triplicate, according to the Clinical Laboratory Standards Institute testing standard, in 96-well plate microbroth dilution assays. Compounds were tested against Gram-negative bacteria (Escherichia coli JW5503, Bukholderia multivorans NBRC 102086 and Bukholderia plantarii NBRC 104884) and Gram-positive

A new analog of dihydroxybenzoic acid from Saccharopolyspora sp. KR21-0001

• Rattiya Janthanom,
• Yuta Kikuchi,
• Hiroki Kanto,
• Tomoyasu Hirose,
• Arisu Tahara,
• Takahiro Ishii,
• Arinthip Thamchaipenet and
• Yuki Inahashi

Beilstein J. Org. Chem. 2024, 20, 497–503, doi:10.3762/bjoc.20.44

• ). Antioxidant activity of 1 was measured via the DPPH radical. 1 showed potent DPPH radical scavenging activity with an IC50 value of 5.0 μg·mL−1, which is lower than that of trolox (IC50; 7.5 μg·mL−1) (Table 2). In contrast, 1 did not show antimicrobial activity against Gram-positive and Gram-negative bacteria

• -positive bacteria, Kocuria rhizophila ATCC 9341 and Bacillus subtilis ATCC 6633; two strains of Gram-negative bacteria, Escherichia coli Europe NIHJ and Xanthomona campestis pv. oryzae KB 88; and two strains of fungi, Candida albicans ATCC 64548 and Mucor racemosus IFO 4581. All strains were tested by

Synthetic approach to 2-alkyl-4-quinolones and 2-alkyl-4-quinolone-3-carboxamides based on common β-keto amide precursors

• Yordanka Mollova-Sapundzhieva,
• Plamen Angelov,
• Danail Georgiev and
• Pavel Yanev

Beilstein J. Org. Chem. 2023, 19, 1804–1810, doi:10.3762/bjoc.19.132

• most prominent examples in this regard are the fluoroquinolone antimicrobials [3] – a remarkably successful drug class, used to treat bacterial infections caused by both Gram-positive and Gram-negative bacteria [4]. Other notable 4-quinolones of synthetic origin are ivacaftor [5] and elvitegravir [6

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

• (five Gram-positive and four Gram-negative bacteria, and three fungi). Additionally, the crystal structures of two berberine variants are described. Several berberine variants show enhanced antibacterial activity compared to the unaltered plant-derived molecule. We also report promising preliminary

• cereus, Bacillus subtilis, Staphylococcus epidermidis, Corynebacterium pseudodiphtheriticum), four Gram-negative bacteria (Escherichia coli, Proteus mirabilis, Enterobacter aerogenes, Enterobacter cloacae), and three fungi (Saccharomyces cerevisiae, Candida albicans, Penicillium chrysogenum). The goal of

• these compounds have been reported before, they were still of interest, as neither compound has been thoroughly assessed for its antimicrobial activity. Our initial pool of berberine variants was screened against 12 microbial organisms (five Gram-positive and four Gram-negative bacteria, and three fungi

Intermediates and shunt products of massiliachelin biosynthesis in Massilia sp. NR 4-1

• Till Steinmetz,
• Blaise Kimbadi Lombe and
• Markus Nett

Beilstein J. Org. Chem. 2023, 19, 909–917, doi:10.3762/bjoc.19.69

• biosynthetic intermediates or shunt products of massiliachelin. Their bioactivity was tested against one Gram-positive and three Gram-negative bacteria. Keywords: Massilia; massiliachelin; siderophore; structure elucidation; Introduction Iron is crucial for many important biological processes, such as

• signal at δH 7.62 ppm characteristic for an amide. In vitro tests were conducted for all compounds to assess their antibacterial activities against three Gram-negative bacteria (Escherichia coli, Agrobacterium tumefaciens and Pseudomonas fluorescens) and one Gram-positive bacterium (Bacillus subtilis

Synthesis of imidazo[1,2-a]pyridine-containing peptidomimetics by tandem of Groebke–Blackburn–Bienaymé and Ugi reactions

• Oleksandr V. Kolomiiets,
• Alexander V. Tsygankov,
• Maryna N. Kornet,
• Aleksander A. Brazhko,
• Vladimir I. Musatov and
• Valentyn A. Chebanov

Beilstein J. Org. Chem. 2023, 19, 727–735, doi:10.3762/bjoc.19.53

• microorganisms (see Table 3 for details). Both Gram-positive and Gram-negative bacteria (specifically, strains of E. coli and B. subtilis) were equally inhibited in their growth. Compound 7o, in particular, was able to inhibit the growth of B. subtilis at a concentration of 125 mg/L. Bacteriostatic activity

Strategies to access the [5-8] bicyclic core encountered in the sesquiterpene, diterpene and sesterterpene series

• Cécile Alleman,
• Charlène Gadais,
• Laurent Legentil and
• François-Hugues Porée

Beilstein J. Org. Chem. 2023, 19, 245–281, doi:10.3762/bjoc.19.23

• -positive and Gram-negative bacteria (Scheme 31B). 4.4 Photocatalyzed oxidative ring expansion: alternative radical chemistry for pleuromutilin scaffold construction Following the advent of photoredox catalysis in ring-opening and ring-expansion chemistry [75], a new route was proposed by Foy and Pronin to

Nostochopcerol, a new antibacterial monoacylglycerol from the edible cyanobacterium Nostochopsis lobatus

• Naoya Oku,
• Saki Hayashi,
• Yuji Yamaguchi,
• Hiroyuki Takenaka and
• Yasuhiro Igarashi

Beilstein J. Org. Chem. 2023, 19, 133–138, doi:10.3762/bjoc.19.13

• -hexane. The resulting three layers were tested against four Gram-positive bacteria, five Gram-negative bacteria, six fungi, and two yeasts, which detected antibacterial activity against two Gram-positive bacteria, Bacillus subtilis and Staphylococcus aureus, from the 90% aqueous MeOH layer. The

Digyalipopeptide A, an antiparasitic cyclic peptide from the Ghanaian Bacillus sp. strain DE2B

• Adwoa P. Nartey,
• Aboagye K. Dofuor,
• Kofi B. A. Owusu,
• Anil S. Camas,
• Hai Deng,
• Marcel Jaspars and
• Kwaku Kyeremeh

Beilstein J. Org. Chem. 2022, 18, 1763–1771, doi:10.3762/bjoc.18.185

• promising antimicrobial properties in comparison to the laboratory standards ampicillin and amphotericin B. Compound 1 produced interesting biological activity against the Gram-negative bacteria Shigella sonnei, Shigella flexneri and the multidrug resistant Gram-positive Staphylococcus aureus with IC50 of

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

• -triazoquinoline derivatives, and the biological activity evaluation showed that most of the compounds had a higher antibacterial activity (the optimal MIC value was 6.25 mg/mL) against Gram-positive bacteria, Gram-negative bacteria and all tested fungi than the standard ciprofloxacin (Figure 1a). Bodke's group

• and other compounds showed similar or lower antifungal activity than norfloxacin. Unfortunately, all compounds were less effective against Gram-negative bacteria (MIC > 128 μg/mL) than the parent drug norfloxacin. To sum up, the synthesized compounds exhibited enhanced antibacterial activity against

On drug discovery against infectious diseases and academic medicinal chemistry contributions

• Yves L. Janin

Beilstein J. Org. Chem. 2022, 18, 1355–1378, doi:10.3762/bjoc.18.141

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

• acid with the heterocyclic moiety 1,3,4-oxadizole was synthesized, and tested for antimicrobial activity against Gram-positive, Gram-negative bacteria, and fungi. Among the synthesized compounds, the most potent derivatives against S. aureus were 4t, 4i, 4p, and 4c with MIC values between 31 and 70 µg

• for their in vitro antibacterial potential against Staphylococcus aureus and Bacillus subtilis as examples of Gram-positive bacteria as well as against Escherichia coli and Proteus vulgaris as examples of Gram-negative bacteria [35]. They were also evaluated for their in vitro antifungal activity

• , compound 4d showed the highest activity against Gram-negative bacteria Proteus vulgaris followed by compounds 4c, 4t, 4b, 4n, 4s, 4l, 4p, 4q, 4i, 4o, 4g and 4j, respectively. All tested compounds exhibited lower activities compared to the tested reference drugs. On the other hand, the order of

Tenacibactins K–M, cytotoxic siderophores from a coral-associated gliding bacterium of the genus Tenacibaculum

• Yasuhiro Igarashi,
• Yiwei Ge,
• Tao Zhou,
• Amit Raj Sharma,
• Enjuro Harunari,
• Naoya Oku and
• Agus Trianto

Beilstein J. Org. Chem. 2022, 18, 110–119, doi:10.3762/bjoc.18.12

• metabolites from Gram-negative bacteria are still quite limited, despite the predominance of this group in the marine environment [10][11]. The genus Tenacibaculum belongs to the family Flavobacteriaceae within the phylum Bacteroidetes. Members of this genus are Gram-negative, aerobic, motile by gliding, and

Total synthesis of the O-antigen repeating unit of Providencia stuartii O49 serotype through linear and one-pot assemblies

• Tanmoy Halder and
• Somnath Yadav

Beilstein J. Org. Chem. 2021, 17, 2915–2921, doi:10.3762/bjoc.17.199

• polysaccharides are one of the important constituents of the surface lipopolysaccharides (LPS) of the cell wall of Gram-negative bacteria. These antigens are responsible for several functions that include adhesion to the host cells and are also found to contribute to the evasion of the host immune responses

• ]. Providencia is a genus of Gram-negative bacteria that belongs to the enterobacteria family and is responsible for causing several enteric infections including urinary tract infections. Providencia includes mainly five virulent species – P. alcalifaciens, P. rettgeri, P. rustigianii, P. stuartii, and P

Biological properties and conformational studies of amphiphilic Pd(II) and Ni(II) complexes bearing functionalized aroylaminocarbo-N-thioylpyrrolinate units

• Samet Poyraz,
• Samet Belveren,
• Sabriye Aydınoğlu,
• Mahmut Ulger,
• Abel de Cózar,
• Maria de Gracia Retamosa,
• Jose M. Sansano and
• H. Ali Döndaş

Beilstein J. Org. Chem. 2021, 17, 2812–2821, doi:10.3762/bjoc.17.192

• anti(myco)bacterial and antifungal activity of newly prepared organometallic compounds were investigated against some Gram-positive, Gram-negative bacteria, M. tuberculosis H37Rv strains and C. albicans, C. tropicalis, C. glabrata fungi. The screened novel complexes showed different degrees of