Archangelolide: A sesquiterpene lactone with immunobiological potential from Laserpitium archangelica

• Silvie Rimpelová,
• Michal Jurášek,
• Lucie Peterková,
• Jiří Bejček,
• Vojtěch Spiwok,
• Miloš Majdl,
• Michal Jirásko,
• Miloš Buděšínský,
• Juraj Harmatha,
• Eva Kmoníčková,
• Pavel Drašar and
• Tomáš Ruml

Beilstein J. Org. Chem. 2019, 15, 1933–1944, doi:10.3762/bjoc.15.189

• ] and was also found to be cytotoxic with localization to the endoplasmic reticulum [8]. The cytotoxicity of compound 2 prompted the preparation and evaluation of compound 2 conjugates with porphyrins [9] and steroids [10] for targeted uptake of compound 2 into cancer cells, and the conjugates showed

• interesting biological effects including antimycobacterial effects [10]. Nevertheless, cytotoxicity posed a considerable limitation for the utilization of compound 2. It was, however, soon found that compound 2 may be modified in such a way that its cytotoxicity is reduced while the immunobiological

• properties are retained [11]. Contrary to compound 2, compound 1 inhibits NO production and synthesis of IL-1β and INF-γ [12]. Although its structure was already elucidated in the 1970s [13], the information on cytotoxicity of compound 1 is very limited [12] and its intracellular localization and mechanism

Morphology-tunable and pH-responsive supramolecular self-assemblies based on AB₂-type host–guest-conjugated amphiphilic molecules for controlled drug delivery

• Yang Bai,
• Cai-ping Liu,
• Di Chen,
• Long-hai Zhuo,
• Huai-tian Bu and
• Wei Tian

Beilstein J. Org. Chem. 2019, 15, 1925–1932, doi:10.3762/bjoc.15.188

• , the biocompatibility of β-CD-BM2-based FSSAs towards PC-3 cells was investigated with different concentrations after incubation for 48 h. The result did not show any cytotoxicity against PC-3 cells (Figure 5a). The viability of PC-3 cells could reach 84% even when the concentration of FSSAs was up to

• investigated. As shown in Figure 5b, DOX-loaded FSSAs displayed reduced cytotoxicity against PC-3 cells in comparison with free DOX·HCl. The in vitro half-maximal inhibitory concentration (IC50) values of DOX-loaded FSSAs and free DOX·HCl after incubation for 48 h were 1.44 and 0.91 μg/mL, respectively. The

• results further certified that the fast intracellular drug-release process of DOX-loaded FSSAs provided a large intracellular drug dose and high cytotoxicity. All these results suggested that DOX-loaded FSSAs presented a potential application in controlled drug delivery. Intracellular uptake of drug

A golden opportunity: benzofuranone modifications of aurones and their influence on optical properties, toxicity, and potential as dyes

• Joza Schmitt and
• Scott T. Handy

Beilstein J. Org. Chem. 2019, 15, 1781–1785, doi:10.3762/bjoc.15.171

• well as its longer term retention and photostability are required. Conclusion In conclusion, the benzofuranone portion of the aurone skeleton does have a definite impact on both the UV–vis spectral and cytotoxicity properties of aurones. Interestingly, the position of the substituent was often more

• displays a significant blue shift by roughly 40 nm. With respect to toxicity, halogens were the least toxic substituents, displaying the lowest cytotoxicity when at the 6- or 7-positions. Hydroxylation or substitution at the 4-position invariably lead to higher cytotoxicity, though often times no worse

N-(1-Phenylethyl)aziridine-2-carboxylate esters in the synthesis of biologically relevant compounds

• Iwona E. Głowacka,
• Aleksandra Trocha,
• Andrzej E. Wróblewski and
• Dorota G. Piotrowska

Beilstein J. Org. Chem. 2019, 15, 1722–1757, doi:10.3762/bjoc.15.168

• (+)-deoxocassine ((2S,3S,6R)-190a) and (+)-spectaline ((2S,3S,6R)-190b) as already described. (+)-Microgrewiapine A ((2R,3S,6R)-194a) [107] and (+)-microcosamine A ((2R,3S,6R)-194b) [108] have recently been isolated and exhibited interesting biological activities, for example cytotoxicity [107]. The total

Synthesis and biological evaluation of truncated derivatives of abyssomicin C as antibacterial agents

• Leticia Monjas,
• Peter Fodran,
• Johanna Kollback,
• Carlo Cassani,
• Thomas Olsson,
• Maja Genheden,
• D. G. Joakim Larsson and
• Carl-Johan Wallentin

Beilstein J. Org. Chem. 2019, 15, 1468–1474, doi:10.3762/bjoc.15.147

• . Accordingly, structure–activity relationship (SAR) studies have been performed, which indicate that benzylation of the hydroxy group and the complete demethylation of the core structure of AbC retain the antibiotic activity towards MRSA while simultaneously decrease cytotoxicity towards various human cell

Synthesis of non-racemic 4-nitro-2-sulfonylbutan-1-ones via Ni(II)-catalyzed asymmetric Michael reaction of β-ketosulfones

• Alexander N. Reznikov,
• Anastasiya E. Sibiryakova,
• Marat R. Baimuratov,
• Eugene V. Golovin,
• Victor B. Rybakov and
• Yuri N. Klimochkin

Beilstein J. Org. Chem. 2019, 15, 1289–1297, doi:10.3762/bjoc.15.127

• cytotoxicity [9]. However, it is of great importance to obtain all stereoisomers for the study of biological activity. Therefore, the development of methods for the asymmetric synthesis of polyfunctional sulfones is valuable. The most notable of them are Ag- and Cu-catalyzed 1,3-dipolar cycloaddition reactions

Photochemical generation of the 2,2,6,6-tetramethylpiperidine-1-oxyl (TEMPO) radical from caged nitroxides by near-infrared two-photon irradiation and its cytocidal effect on lung cancer cells

• Ayato Yamada,
• Manabu Abe,
• Yoshinobu Nishimura,
• Shoji Ishizaka,
• Masashi Namba,
• Taku Nakashima,
• Kiyofumi Shimoji and
• Noboru Hattori

Beilstein J. Org. Chem. 2019, 15, 863–873, doi:10.3762/bjoc.15.84

• (0, 10, 100 μg mL−1) and further incubated for 4 h under the same conditions. Without exposure to light, 2a itself exhibited slight cytotoxicity based on trypan blue exclusion, and ≈80–90% living cells remained in the medium containing of 100 μg mL−1 of 2a (Supporting Information File 1, Figure S8

• 2a induced cancer cell death in vitro, although no in vivo study was performed because of the low water solubility of 2a. At this point, we cannot rule out generate of ROS by photosensitization of the chromophore in the presence of O2 for the cytotoxicity. Conclusion In the present study, novel caged

Cyclopropene derivatives of aminosugars for metabolic glycoengineering

• Jessica Hassenrück and
• Valentin Wittmann

Beilstein J. Org. Chem. 2019, 15, 584–601, doi:10.3762/bjoc.15.54

• conditions and microscopy settings resulted in a bright staining for Ac4GlcNCp and Ac4GalNCp well over that of the negative control (Figure 5). These results were confirmed by flow cytometry (Figure 4 and Figure 5). Interestingly, we did not observe cytotoxicity of Ac4GlcNCp up to a concentration of 100 μM

• . Comparison of glucosamine and galactosamine derivatives Having proven the suitability of Ac4GlcNCp for MGE, we next compared it with Ac4GlcNCyoc. First, we investigated the staining intensity on the cell surface by confocal fluorescence microscopy. Owing to the cytotoxicity of Ac4GlcNCyoc, a concentration of

Synthesis of the polyketide section of seragamide A and related cyclodepsipeptides via Negishi cross coupling

• Jan Hendrik Lang and
• Thomas Lindel

Beilstein J. Org. Chem. 2019, 15, 577–583, doi:10.3762/bjoc.15.53

• cytotoxicity [3]. A photoreactive derivative of the cytotoxic jasplakinolides, geodiamolides [4][5], or seragamides (2–6, seragamides A–E) [6] could also enable the search for additional targets in the cell, including proteins involved in transport or even membrane components. For this purpose, the 2

Synthesis and fluorescent properties of N(9)-alkylated 2-amino-6-triazolylpurines and 7-deazapurines

• Andrejs Šišuļins,
• Jonas Bucevičius,
• Yu-Ting Tseng,
• Irina Novosjolova,
• Kaspars Traskovskis,
• Ērika Bizdēna,
• Huan-Tsung Chang,
• Sigitas Tumkevičius and
• Māris Turks

Beilstein J. Org. Chem. 2019, 15, 474–489, doi:10.3762/bjoc.15.41

• to increased fluorescence quantum yield (74%) in THF solution. The compounds exhibit low cytotoxicity and as such are useful for the cell labelling studies in the future. Keywords: 7-deazapurines; fluorescence; nucleophilic aromatic substitution; purines; push–pull systems; pyrrolo[2,3-d]pyrimidines

• lines – luminal A breast cancer cell line MCF7 and triple negative breast cancer cell line MDAMB231. The results were compared with those obtained on normal breast epithelial cell line (MCF-10A). All compounds showed low cytotoxicity on all tested cell lines (for Figure S81 see Supporting Information

• File 1). Bearing in mind fluorescent properties and low cytotoxicity of the newly obtained compounds, we tested their potential application in cell staining. The preliminary experiments revealed that the compounds went through the cell membrane after 1 h or 2 h incubation period and localized uniformly

Synthesis of a tubugi-1-toxin conjugate by a modulizable disulfide linker system with a neuropeptide Y analogue showing selectivity for hY1R-overexpressing tumor cells

• Rainer Kufka,
• Robert Rennert,
• Goran N. Kaluđerović,
• Lutz Weber,
• Wolfgang Richter and
• Ludger A. Wessjohann

Beilstein J. Org. Chem. 2019, 15, 96–105, doi:10.3762/bjoc.15.11

• Pharmaceuticals GmbH, Leberstr. 20, A-1110 Vienna, Austria 10.3762/bjoc.15.11 Abstract Tubugi-1 is a small cytotoxic peptide with picomolar cytotoxicity. To improve its cancer cell targeting, it was conjugated using a universal, modular disulfide derivative. This allowed conjugation to a neuropeptide-Y (NPY

Repurposing the anticancer drug cisplatin with the aim of developing novel Pseudomonas aeruginosa infection control agents

• Mingjun Yuan,
• Song Lin Chua,
• Yang Liu,
• Daniela I. Drautz-Moses,
• Joey Kuok Hoong Yam,
• Thet Tun Aung,
• Roger W. Beuerman,
• May Margarette Santillan Salido,
• Stephan C. Schuster,
• Choon-Hong Tan,
• Michael Givskov,
• Liang Yang and
• Thomas E. Nielsen

Beilstein J. Org. Chem. 2018, 14, 3059–3069, doi:10.3762/bjoc.14.284

• , homogenized in 1 mL 0.9% NaCl, serially diluted and plated on LB agar plates for incubation at 37 °C overnight. Colonies on the plate were counted and CFU mL−1 was tabulated. Experiments were conducted in triplicate, and results are shown as the mean ± s.d. RAW264.7 macrophage cytotoxicity assay The murine

• . aeruginosa was correlated with acute cytotoxicity to host epithelial cells and immune cells such as macrophages and neutrophils [38]. As we demonstrated that cisplatin treatment was able to reduce the T3SS of P. aeruginosa, we further tested the ability of cisplatin in attenuating the acute cytotoxicity of P

• between groups. *P ≤ 0.05. (B) Cisplatin treatment reduced cytotoxicity of P. aeruginosa PAO1 against mouse macrophage cells. Means and s.d. from triplicate experiments are shown. Student’s t-test was performed for testing differences between groups. *P ≤ 0.05. P. aeruginosa biofilm killing assay by

N-Acylated amino acid methyl esters from marine Roseobacter group bacteria

• Hilke Bruns,
• Lisa Ziesche,
• Nargis Khakin Taniwal,
• Laura Wolter,
• Thorsten Brinkhoff,
• Jennifer Herrmann,
• Rolf Müller and
• Stefan Schulz

Beilstein J. Org. Chem. 2018, 14, 2964–2973, doi:10.3762/bjoc.14.276

• against E. coli TolC, and it was the only compound that showed moderate cytotoxicity on a human cancer cell line. The close similarity of NAMEs, NAVMEs, and NAGMEs to AHLs might indicate a function as signalling compounds, although experiments with NAMEs and AHL reporter assays did not reveal any activity

• (minimum inhibitory concentration, MIC, in µg/mL) and cytotoxicity (minimum inhibitory concentration, MIC, in µg/mL) of selected NAVME, NABME and NAGME derivatives. Minimal inhibitory concentration and IC50 values for cytotoxicity in μg/mL. Supporting Information Supporting Information File 428

Targeting the Pseudomonas quinolone signal quorum sensing system for the discovery of novel anti-infective pathoblockers

• Christian Schütz and
• Martin Empting

Beilstein J. Org. Chem. 2018, 14, 2627–2645, doi:10.3762/bjoc.14.241

• molecule [34]. This autoinducer has been described to mediate iron acquisition, cytotoxicity, outer-membrane vesicle biogenesis, and to exert host immune modulatory effects [34][35]. Interestingly, PQS as well as HHQ are able to interfere with nuclear transcription factor-κB and hypoxia-inducible factor 1

• by pqs QS, pyocyanin is one of the most prominent. This redox-active pigment is responsible for the greenish-blueish colour of P. aeruginosa cultures. It seems that generation of reactive oxygen species is a major mechanism of pyocyanin cytotoxicity [41]. This tricyclic compound is known to induce

Pathoblockers or antivirulence drugs as a new option for the treatment of bacterial infections

• Matthew B. Calvert,
• Varsha R. Jumde and
• Alexander Titz

Beilstein J. Org. Chem. 2018, 14, 2607–2617, doi:10.3762/bjoc.14.239

• plasma and liver microsomes, absence of cytotoxicity, and excellent oral bioavailability in mice. 4. Direct toxin inhibition Numerous bacteria secrete toxins that are responsible for acute virulence. Various small molecule and antibody approaches target the inhibition of bacterial toxins in order to

Synthesis of 3-aminocoumarin-N-benzylpyridinium conjugates with nanomolar inhibitory activity against acetylcholinesterase

• Nisachon Khunnawutmanotham,
• Cherdchai Laongthipparos,
• Patchreenart Saparpakorn,
• Nitirat Chimnoi and
• Supanna Techasakul

Beilstein J. Org. Chem. 2018, 14, 2545–2552, doi:10.3762/bjoc.14.231

• was inactive against MRC-5 normal embryonic lung cell (0% cytotoxicity at concentration of 50 μg/mL). Molecular docking studies Molecular docking studies [15] were performed to study the binding mode and interactions of the synthesized compounds with AChE. A crystal structure of recombinant human

Comparative cell biological study of in vitro antitumor and antimetastatic activity on melanoma cells of GnRH-III-containing conjugates modified with short-chain fatty acids

• Eszter Lajkó,
• Sarah Spring,
• Rózsa Hegedüs,
• Beáta Biri-Kovács,
• Sven Ingebrandt,
• Gábor Mező and
• László Kőhidai

Beilstein J. Org. Chem. 2018, 14, 2495–2509, doi:10.3762/bjoc.14.226

• melanoma cells was increased by [4Lys(Ac)]-GnRH-III(Dau=Aoa), while the GnRH-III(Dau=Aoa) and [4Lys(Bu)]-GnRH-III(Dau=Aoa) decreased this activity. Conclusion: Internalization and cytotoxicity of the conjugates showed that GnRH-III peptides could guard Dau to melanoma cells and promote antitumor activity

• . [4Lys(Bu)]-GnRH-III(Dau=Aoa) possessing the butyryl side chain acting as a “second drug” proved to be the best candidate for targeted tumor therapy due to its cytotoxicity and immobilizing effect on tumor cell spreading. The applicability of impedimetry and holographic phase imaging for characterizing

• electrode surface, makes this impedimetric assay sensitive enough for cytotoxicity experiments [36]. In the event of a cytotoxic compound, the cells detach from the electrode surface and a drop in the impedance – given as Cell index values – could be observed. According to the time-course study, the

Correction: 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. 2018, 14, 2394–2395, doi:10.3762/bjoc.14.215

• benzenoid derivatives; cytotoxicity; marine alga-derived fungus; Paecilomyces variotii; TDDFT-ECD calculation; The authors wish to rename compounds 1 and 2 (shown in Figure 1 of the original article [1]) as varioloids C and D, respectively (Figure 1), as the synonyms varioloids A and B have already been

Stereoselective total synthesis and structural revision of the diacetylenic diol natural products strongylodiols H and I

• Pamarthi Gangadhar,
• Sayini Ramakrishna,
• Ponneri Venkateswarlu and
• Pabbaraja Srihari

Beilstein J. Org. Chem. 2018, 14, 2313–2320, doi:10.3762/bjoc.14.206

• )- and (S)-methoxy(2-naphthyl)acetic acid) derivatives. Though petrosiols A, D and E along with strongylodiols C and D were found to display neuronal differentiation of PC12 cells in a dose-dependent manner and induce neuronal outgrowth, strongylodiols C and D also displayed cytotoxicity at higher

Natural and redesigned wasp venom peptides with selective antitumoral activity

• Marcelo D. T. Torres,
• Gislaine P. Andrade,
• Roseli H. Sato,
• Cibele N. Pedron,
• Tania M. Manieri,
• Giselle Cerchiaro,
• Anderson O. Ribeiro,
• Cesar de la Fuente-Nunez and
• Vani X. Oliveira Jr.

Beilstein J. Org. Chem. 2018, 14, 1693–1703, doi:10.3762/bjoc.14.144

• rather than Arg due to its superior flexibility, lower propensity in potentially toxic cell-penetrating peptides [29], and decreased hydrophobic side chain, which is associated with cytotoxicity [30]. Moreover, Lys residues are more frequent than Arg residues in naturally occurring wasp venom peptides

• . Furthermore, Dec-NH2 and its analogs were hemolytic at concentrations above their MIC values for the different microorganisms studied [9][10]. MTT cytotoxicity assays MTT assays were performed to determine the toxicity of designer peptides against MCF-7 cancer cells and MCF-10A normal cells. MCF-10A cells

• -Dec-NH2 behaves similarly to the template molecule, achieving >50% of cancer cell lysis at 25 μmol L−1 after 2 h of exposure and at 12.5 μmol L−1 after 24 h. Their cytotoxicity levels were similar when tested against MCF-10A normal cells (Figure 3), showing no significant cytotoxicity even at higher

β-Hydroxy sulfides and their syntheses

• Mokgethwa B. Marakalala,
• Edwin M. Mmutlane and
• Henok H. Kinfe

Beilstein J. Org. Chem. 2018, 14, 1668–1692, doi:10.3762/bjoc.14.143

• Brevibacillus sp. collected off the coast of Japan [7]; and brocazine G (6), a bisthiodiketopiperazine which displayed potent cytotoxicity to sensitive and cisplatin resistant human tumor cell lines (HTCLs) and strong activity against S. aureus [8]. Further examples illustrating the structural diversity and

Drug targeting to decrease cardiotoxicity – determination of the cytotoxic effect of GnRH-based conjugates containing doxorubicin, daunorubicin and methotrexate on human cardiomyocytes and endothelial cells

• Livia Polgár,
• Eszter Lajkó,
• Pál Soós,
• Orsolya Láng,
• Marilena Manea,
• Béla Merkely,
• Gábor Mező and
• László Kőhidai

Beilstein J. Org. Chem. 2018, 14, 1583–1594, doi:10.3762/bjoc.14.136

• -conjugates containing doxorubicin, daunorubicin and methotrexate were investigated in this study. Their cytotoxicity was determined on primary human cardiac myocytes (HCM) and human umbilical vein endothelial cells (HUVEC) using the xCELLigence SP system, which measures impedance changes caused by adhering

• cells on golden electrode arrays placed at the bottom of the wells. Slopes of impedance–time curves were calculated and for the quantitative determination of cytotoxicity, the difference to the control was analysed. Results: Doxorubicin and daunorubicin exhibited a cytotoxic effect on both cell types

• cytotoxic effect on cardiomyocytes were identified. In the future, these compounds could provide a more targeted antitumor therapy with no cardiotoxic adverse effects. Moreover, impedimetric cytotoxicity analysis could be a valuable technique to determine the effect of drugs on cardiomyocytes. Keywords

Lanyamycin, a macrolide antibiotic from Sorangium cellulosum, strain Soce 481 (Myxobacteria)

• Lucky S. Mulwa,
• Rolf Jansen,
• Dimas F. Praditya,
• Kathrin I. Mohr,
• Patrick W. Okanya,
• Joachim Wink,
• Eike Steinmann and
• Marc Stadler

Beilstein J. Org. Chem. 2018, 14, 1554–1562, doi:10.3762/bjoc.14.132

• of which were found to exert anti-HIV activity while sorazolones, argyrins and tubulysins showed antitumor activity or cytotoxicity [4][5][6][7][8]. In our studies on the secondary metabolites of Sorangium cellulosum (strain Soce 481), we observed strong antifungal activity in the raw extract. On RP

• activity against bacteria and fungi and showed moderate antifungal activity in addition to a good inhibition of Micrococcus luteus (Table 3). When lanyamycin (1/2) was evaluated for cytotoxicity against growing primary cell lines, mouse fibroblasts (L929), and human cancer cell lines, nasopharyngeal cells

• IC50 values ≤10 µM) [16] (Table 4). Lanyamycin (1/2) showed an inhibition of HCV infection with an IC50 value of 11.8 µM, without any cytotoxicity of the human liver cells, which was simultaneously determined (see Figure 5 and for viability assay, Supporting Information File 1, Figures S9 and S10). The

Two new 2-alkylquinolones, inhibitory to the fish skin ulcer pathogen Tenacibaculum maritimum, produced by a rhizobacterium of the genus Burkholderia sp.

• Dandan Li,
• Naoya Oku,
• Atsumi Hasada,
• Masafumi Shimizu and
• Yasuhiro Igarashi

Beilstein J. Org. Chem. 2018, 14, 1446–1451, doi:10.3762/bjoc.14.122

• revealed 5-lipoxygenase inhibitory activity [33], plant-growth promoting activity [32][34], and IGF-dependent cell-specific cytotoxicity [14]. A recent metabolomic analysis using LC–MS verified the presence of more than 50 2-alkyl-4-quinolones [35], most of which remain chemically and biologically

Design and biological characterization of novel cell-penetrating peptides preferentially targeting cell nuclei and subnuclear regions

• Anja Gronewold,
• Mareike Horn and
• Ines Neundorf

Beilstein J. Org. Chem. 2018, 14, 1378–1388, doi:10.3762/bjoc.14.116

• ) with selective suborganelle-targeting properties. The nuclear localization sequence N50, as well as the nucleoli-targeting sequence NrTP, respectively, were fused to a shortened version of the cell-penetrating peptide sC18. We examined cellular uptake, subcellular fate and cytotoxicity of these novel

• -sC18* and NrTP-sC18* formed α-helices that showed amphipathic character with a clear hydrophilic and hydrophobic face (Figure 1C). This property might support the interaction with the plasma membrane. Cytotoxic profile of novel CPPs In the next step, the cytotoxicity profiles of the novel peptide

• when co-administered with the novel peptides (Figure 7A and 7B). Since this effect was more intense in MCF-7 cells, these cells were used for a following cytotoxicity assay. Herein, the drug alone (1 μg/mL) or in presence of 10 μM solutions of the peptides sC18*, N50-sC18* and NrTP-sC18*, respectively