Anti-inflammatory aromadendrane- and cadinane-type sesquiterpenoids from the South China Sea sponge Acanthella cavernosa

• Shou-Mao Shen,
• Qing Yang,
• Yi Zang,
• Jia Li,
• Xueting Liu and
• Yue-Wei Guo

Beilstein J. Org. Chem. 2022, 18, 916–925, doi:10.3762/bjoc.18.91

• diterpenes with characteristic isocyano, isothiocyano, and formamido functionalities [2][3][4][5]. Many of these secondary metabolites merit further investigation due to their intriguing structural diversity and wide spectra of biological activities ranging from antifeedant, antifouling, and cytotoxic to

Efficient production of clerodane and ent-kaurane diterpenes through truncated artificial pathways in Escherichia coli

• Fang-Ru Li,
• Xiaoxu Lin,
• Qian Yang,
• Ning-Hua Tan and
• Liao-Bin Dong

Beilstein J. Org. Chem. 2022, 18, 881–888, doi:10.3762/bjoc.18.89

• diterpenoids are two categories of diterpenoids that are widely distributed in terrestrial plants, fungi, and a few bacteria and possess broad pharmacological bioactivities [1][2][3]. Representative natural products containing these skeletons are terpentecin (cytotoxic and antibiotic), salvinorin A (kappa

• opioid receptor), oridonin (cytotoxic), and gibberellin (phytohormone) (Figure 1b) [24][25][26][27]. How to efficiently construct the core carbon skeletons is a critical question in utilizing the advanced ‘two-phase strategy’ or chemoenzymatic synthesis to readily synthesize clerodane and ent-kaurane

Terpenoids from Glechoma hederacea var. longituba and their biological activities

• Dong Hyun Kim,
• Song Lim Ham,
• Zahra Khan,
• Sun Yeou Kim,
• Sang Un Choi,
• Chung Sub Kim and
• Kang Ro Lee

Beilstein J. Org. Chem. 2022, 18, 555–566, doi:10.3762/bjoc.18.58

• , nerve growth factor (NGF) secretion stimulation activities in C6 glioma cells, and cytotoxic activities against four human cancer cell lines (A549, SK-OV-3, SK-MEL-2, and HCT15). Compounds 2 and 5–7 exhibited inhibitory effects on the NO production with IC50 values of 52.21, 47.90, 61.61, and 25.35 μM

• , respectively. Compound 5 also exhibited a significant stimulating effect on NGF secretion (122.77 ± 8.10%). Compound 9 showed potent cytotoxic activity against SK-OV-3 (IC50 = 3.76 μM) and SK-MEL-2 (IC50 = 1.48 μM) cell lines, while 7 displayed a strong cytotoxic activity against the SK-MEL-2 (IC50 = 9.81 μM

• , lignans, flavonoids, and phenolic compounds that show anti-inflammatory, cytotoxic, and/or cytoprotective effects [3][4][5][6][7]. However, bioactive terpenoids of G. hederacea var. longituba with antineurodegenerative effects remain largely unknown. In this study, nine terpenoids (1–9) including five new

Unusual highly diastereoselective Rh(II)-catalyzed dimerization of 3-diazo-2-arylidenesuccinimides provides access to a new dibenzazulene scaffold

• Anastasia Vepreva,
• Alexander S. Bunev,
• Andrey Yu. Kudinov,
• Grigory Kantin,
• Mikhail Krasavin and
• Dmitry Dar’in

Beilstein J. Org. Chem. 2022, 18, 533–538, doi:10.3762/bjoc.18.55

• against the A549 human lung adenocarcinoma cell line while N-aryl analogs were non-cytotoxic. Keywords: diazo arylidene succinimides; dibenzoazulenodipyrroles; indenopyrroles; Rh2(esp)2-catalyzed decomposition; unsymmetrical dimers; Introduction 3-Diazo-2-arylidenesuccinimides 1 (DAS) are heterocyclic

• showed pronounced cytotoxocity against the A549 human lung adenocarcinoma cell line while N-aryl analogs were non-cytotoxic. Previously reported transformations of DAS (1) and their unusual dimerization investigated in this work. Cytotoxicity of N-alkyl-substituted dibenzoazulenodipyrroles 2 against the

Chemistry of polyhalogenated nitrobutadienes, 17: Efficient synthesis of persubstituted chloroquinolinyl-1H-pyrazoles and evaluation of their antimalarial, anti-SARS-CoV-2, antibacterial, and cytotoxic activities

• Viktor A. Zapol’skii,
• Isabell Berneburg,
• Ursula Bilitewski,
• Melissa Dillenberger,
• Katja Becker,
• Stefan Jungwirth,
• Aditya Shekhar,
• Bastian Krueger and
• Dieter E. Kaufmann

Beilstein J. Org. Chem. 2022, 18, 524–532, doi:10.3762/bjoc.18.54

• ± 0.04 µM (100 ng/mL, 200 nM), respectively. Two compounds (3b and 10d) have also been tested for anti-SARS-CoV-2, antibacterial, and cytotoxic activity. Keywords: antimalarial activity; anti-SARS-CoV-2 activity; chloroquine; 2-nitroperchlorobutadiene; nucleophilic vinylic substitution; 1H-pyrazoles

• persubstituted pyrazoles were unknown until now. In addition, it is known that polyhalogenated nitrobutadienes are versatile synthetic precursors for many bioactive heterocycles such as insecticidal neonicotinoids [34]. Evaluation of biological properties Antibacterial and cytotoxic properties The general

• cytotoxic activities of compounds 3b and 10d were studied, as they influence the applicability of the compounds in other assays comprising mammalian cells. We incubated the murine fibroblast L929 cell line with different concentrations of the compounds for 72 h and quantified the residual viability of the

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

• . Compound 2 possesses a rare bicyclic sesquiterpene skeleton. The antimicrobial and cytotoxic activities of the isolated compounds were evaluated. Keywords: antimicrobial activity; cytotoxic activity; γ-lactone; soil-derived fungus; sesquiterpene; Trichoderma citrinoviride; Introduction The fungus

• Trichoderma citrinoviride produces structurally diverse secondary metabolites including diterpenes [1][2], alkaloids [3], sorbicillinoids [4][5], long chain alcohols [6], and cyclonerane sesquiterpenes [7]. Some of them display antibacterial [1][2][7], cytotoxic [3], anti-inflammatory [4], and antimicroalgal

• , we report the isolation and structure elucidation as well as antimicrobial and cytotoxic activities of some isolated compounds which were obtained in sufficient amount. Results and Discussion Chemical investigation of the broth and mycelial extracts of T. citrinoviride PSU-SPSF346 by various

Four bioactive new steroids from the soft coral Lobophytum pauciflorum collected in South China Sea

• Di Zhang,
• Zhe Wang,
• Xiao Han,
• Xiao-Lei Li,
• Zhong-Yu Lu,
• Bei-Bei Dou,
• Wen-Ze Zhang,
• Xu-Li Tang,
• Ping-Lin Li and
• Guo-Qiang Li

Beilstein J. Org. Chem. 2022, 18, 374–380, doi:10.3762/bjoc.18.42

• containing side chains with 23,24-dimethyl groups and (17)20E double bond, have been reported to be frequently isolated from soft corals of this genus, some of them exhibited anti-inflammatory [4], cytotoxic [5][6], and antibacterial activities [7]. To search for bioactive natural products, we have

• , demethylgorgosterol [9][10]. Thus, the structure of compound 4 was assigned as shown in Figure 1. Biological activity The cytotoxic activities of compounds 1–7 were evaluated against three cancer cell lines (HL-60, K562, and Hela), but only compound 1 exhibited weak cytotoxic activity against K562 cells with an IC50

• methyl group at C-4. The absolute configuration of 1–3 was determined by X-ray diffraction analyses. Compounds 1–7 were subjected to a cytotoxic activity evaluation against HL-60, K562, and Hela cells, only compound 1 exhibited weak cytotoxic activity against K562 cells with an IC50 value of 19.03 μM. In

Synthesis and bioactivity of pyrrole-conjugated phosphopeptides

• Qiuxin Zhang,
• Weiyi Tan and
• Bing Xu

Beilstein J. Org. Chem. 2022, 18, 159–166, doi:10.3762/bjoc.18.17

• cytotoxicity, 15c is less cytotoxic. This result agrees with the observation that dipyrrole-conjugated peptides, in general, exhibit higher inhibitory activity against HeLa cells than mono- or tripyrrole-conjugated peptides do. It is interesting that 4a exhibits higher inhibitory activity than that of 2g

Ready access to 7,8-dihydroindolo[2,3-d][1]benzazepine-6(5H)-one scaffold and analogues via early-stage Fischer ring-closure reaction

• Irina Kuznetcova,
• Felix Bacher,
• Daniel Vegh,
• Hsiang-Yu Chuang and
• Vladimir B. Arion

Beilstein J. Org. Chem. 2022, 18, 143–151, doi:10.3762/bjoc.18.15

• unit is shifted and the indole ring is flipped (D). Isomer D has been shown to be a potent tubulin-polymerase inhibitor, while B was only mildly cytotoxic towards cancer cells at a concentration of 1 µM [5][6]. Backbone C, despite being very similar to the other three scaffolds, remained a synthetic

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

• available on the secondary metabolites from this genus [17][18]. In our continuing search for bioactive compounds from underexplored marine bacteria [19][20][21], a Tenacibaculum strain, isolated from a stony coral, was found to produce three metabolites, which turned out to be new cytotoxic hydroxamate

Chemical and chemoenzymatic routes to bridged homoarabinofuranosylpyrimidines: Bicyclic AZT analogues

• Sandeep Kumar,
• Jyotirmoy Maity,
• Banty Kumar,
• Sumit Kumar and
• Ashok K. Prasad

Beilstein J. Org. Chem. 2022, 18, 95–101, doi:10.3762/bjoc.18.10

• acetylation; Introduction In the last few decades, modification of nucleoside/nucleotide analogues has been a field of keen interest to researchers due to their therapeutic properties for treatment of cancer, viral and microbial infections [1][2][3][4][5][6][7][8][9]. The very first cytotoxic

Efficient synthesis of ethyl 2-(oxazolin-2-yl)alkanoates via ethoxycarbonylketene-induced electrophilic ring expansion of aziridines

• Yelong Lei and
• Jiaxi Xu

Beilstein J. Org. Chem. 2022, 18, 70–76, doi:10.3762/bjoc.18.6

• some natural products [2] and pharmaceuticals [3], such as in the antitumor epi-oxazoline halipeptin D isolated from marine organisms [4], in the cytotoxic natural depsipeptide brasilibactin A [5], and cyclohexapeptide bistratamide A [6] (Figure 1). Oxazoline is also one of the crucial coordinating

1,2-Naphthoquinone-4-sulfonic acid salts in organic synthesis

• Ruan Carlos B. Ribeiro,
• Patricia G. Ferreira,
• Amanda de A. Borges,
• Luana da S. M. Forezi,
• Fernando de Carvalho da Silva and
• Vitor F. Ferreira

Beilstein J. Org. Chem. 2022, 18, 53–69, doi:10.3762/bjoc.18.5

• human cancer cell lines, including leukemia (HL-60), melanoma (MDA-MB-435), colon cancer (HCT-116), and central nervous system cancer (SF-295). 4-Amino-1,2-naphthoquinones 43a–c exhibited considerable cytotoxic activities, with 43a being the most active against HL-60 and MDA-MB-435 cells (Scheme 12

Efficient N-arylation of 4-chloroquinazolines en route to novel 4-anilinoquinazolines as potential anticancer agents

• Rodolfo H. V. Nishimura,
• Thiago dos Santos,
• Valter E. Murie,
• Luciana C. Furtado,
• Leticia V. Costa-Lotufo and
• Giuliano C. Clososki

Beilstein J. Org. Chem. 2021, 17, 2968–2975, doi:10.3762/bjoc.17.206

• ). The EGFR inhibitor drugs bearing the 4-anilinoquinazoline moiety did not show potent cytotoxic activity against T98G cells (21.3 µM for erlotinib, and 37.8 µM for gefitinib). However, the tubulin polymerization inhibitor (verubulin), which contains 4-anilinoquinazoline in its chemical structure, was

• strongly cytotoxic to T98G cells (0.2 nM). In fact, the promising activity of verubulin in glioma is known, which has prompted phase 2 clinical trials in patients with recurrent glioblastoma, but the studies have been interrupted due to the observed adverse events [33]. Nonetheless, further studies aiming

Unsaturated fatty acids and a prenylated tryptophan derivative from a rare actinomycete of the genus Couchioplanes

• Shun Saito,
• Kanji Indo,
• Naoya Oku,
• Hisayuki Komaki,
• Masashi Kawasaki and
• Yasuhiro Igarashi

Beilstein J. Org. Chem. 2021, 17, 2939–2949, doi:10.3762/bjoc.17.203

• were weakly inhibitory against Kocuria rhizophila at MIC 100 μg/mL and none were cytotoxic against P388 at the same concentration. Keywords: Couchioplanes; prenylated tryptophan; rare actinomycete; unsaturated fatty acid; Introduction Actinomycetes, a subgroup of filamentous Gram-positive bacteria

• H-13 (Figure 6). Thus, an S-configuration, corresponding to an ʟ-chirality for tryptophan, was assigned. Compounds 1–6 were not cytotoxic against P388 murine leukemia cells (IC50 > 100 μM), nor antimicrobial against five bacteria, Bacillus subtilis, Staphylococcus aureus, Ralstonia solanacearum

Synthesis of new pyrazolo[1,2,3]triazines by cyclative cleavage of pyrazolyltriazenes

• Nicolai Wippert,
• Martin Nieger,
• Claudine Herlan,
• Nicole Jung and
• Stefan Bräse

Beilstein J. Org. Chem. 2021, 17, 2773–2780, doi:10.3762/bjoc.17.187

• of the target compounds of class 5 were chosen as they were available in sufficient amounts and showed no decomposition during storage and dilution in DMSO. Also, most of the intermediates showed no reduction of cell viability; however, compounds 9b, 12b,c, 13a,b, and 13f–h showed some cytotoxic

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

• has been reported for benzylisoquinoline alkaloids, including spasmolytic, narcotic, dopaminergic, ion-channel modulating, and cytotoxic properties. Occurrence, biosynthesis and pharmacology of benzylisoquinoline alkaloids has been reviewed comprehensively by Hagel and Facchini [1]. Synthetic

• -tetrahydroisoquinoline alkaloids (Figure 2 and Table 1). Since, as mentioned above, we recently demonstrated that substituted 1-benzyl-1,2,3,4-tetrahydroisoquinolines exhibit both cytotoxic and calcium channel-modulating activities, we subjected these alkaloids to our established screening systems in order to gain new

Ligand-dependent stereoselective Suzuki–Miyaura cross-coupling reactions of β-enamido triflates

• Tomáš Chvojka,
• Athanasios Markos,
• Svatava Voltrová,
• Radek Pohl and
• Petr Beier

Beilstein J. Org. Chem. 2021, 17, 2657–2662, doi:10.3762/bjoc.17.179

• of cytotoxic, antifungal, or antibiotic properties [10][11][12]. Modern stereoselective syntheses leading to highly substituted enamides include cross-coupling of vinyl (pseudo)halides or organoboron compounds [13], hydroamidation of alkynes [14][15][16], ynamide functionalization [17][18][19], or

α-Ketol and α-iminol rearrangements in synthetic organic and biosynthetic reactions

• Scott Benz and
• Andrew S. Murkin

Beilstein J. Org. Chem. 2021, 17, 2570–2584, doi:10.3762/bjoc.17.172

• reduction in conjugation. Another example of a tandem α-ketol rearrangement was used in the total synthesis of delitschiapyrone A (49), a cytotoxic natural product with previously demonstrated efficacy against several cancer cell lines. The final steps of the synthesis include a Diels–Alder reaction between

Strategies for the synthesis of brevipolides

• Yudhi D. Kurniawan and
• A'liyatur Rosyidah

Beilstein J. Org. Chem. 2021, 17, 2399–2416, doi:10.3762/bjoc.17.157

• [4]. These compounds demonstrated cytotoxicity against various human cancer cells. Additionally, the research group led by Pereda-Miranda later isolated more members of brevipolide (1–15) from the same plant during 2013–2017 and further confirmed the cytotoxic activity of these natural products [1

Phenolic constituents from twigs of Aleurites fordii and their biological activities

• Kyoung Jin Park,
• Won Se Suh,
• Da Hye Yoon,
• Chung Sub Kim,
• Sun Yeou Kim and
• Kang Ro Lee

Beilstein J. Org. Chem. 2021, 17, 2329–2339, doi:10.3762/bjoc.17.151

• stereochemistry, but they showed quite different inhibition effects on NO production (IC50 55.0 μM, 2; IC50 > 500 μM, 5). The MTT cell viability test suggested that all the compounds had no cytotoxic effect on BV-2 cell survival at a concentration of 20 μM. Compounds 1–19 were also tested for their

Post-functionalization of drug-loaded nanoparticles prepared by polymerization-induced self-assembly (PISA) with mitochondria targeting ligands

• Janina-Miriam Noy,
• Fan Chen and
• Martina Stenzel

Beilstein J. Org. Chem. 2021, 17, 2302–2314, doi:10.3762/bjoc.17.148

• only rely on that reaction to introduce cell apoptosis, as all particle systems are cytotoxic regardless of reaching the mitochondria or not. The mitochondria contain indeed several vicinal protein thiols that readily react with trivalent arsenicals, however, it has been shown that various other

(Phenylamino)pyrimidine-1,2,3-triazole derivatives as analogs of imatinib: searching for novel compounds against chronic myeloid leukemia

• Luiz Claudio Ferreira Pimentel,
• Lucas Villas Boas Hoelz,
• Henayle Fernandes Canzian,
• Frederico Silva Castelo Branco,
• Andressa Paula de Oliveira,
• Vinicius Rangel Campos,
• Floriano Paes Silva Júnior,
• Rafael Ferreira Dantas,
• Jackson Antônio Lamounier Camargos Resende,
• Anna Claudia Cunha,
• Nubia Boechat and
• Mônica Macedo Bastos

Beilstein J. Org. Chem. 2021, 17, 2260–2269, doi:10.3762/bjoc.17.144

• analysis, the molecular structure was confirmed, as shown in Figure 2. Biological assay The compounds showed significant inhibitory activity at 10 μM but not at 1 μM (Figure 3). Compounds 2c, 2d, and 2g were the most promising, and concentration–response curves were drawn to determine the cytotoxic

• , 2c, 2d, and 2g with the BCR-Abl-1 structure (PDB code: 3PYY), showing steric interactions (red dotted lines) and hydrogen bonds (blue dotted lines). Synthetic route of the triazole derivatives 1a,b, and 2a–j. Cytotoxic activity, confidence interval, and selectivity index of imatinib and derivatives

Nomimicins B–D, new tetronate-class polyketides from a marine-derived actinomycete of the genus Actinomadura

• Zhiwei Zhang,
• Tao Zhou,
• Taehui Yang,
• Keisuke Fukaya,
• Enjuro Harunari,
• Shun Saito,
• Katsuhisa Yamada,
• Chiaki Imada,
• Daisuke Urabe and
• Yasuhiro Igarashi

Beilstein J. Org. Chem. 2021, 17, 2194–2202, doi:10.3762/bjoc.17.141

• collection sites [12]. Furthermore, we found that the DSW of Sagami Bay (Pacific Ocean side of Honshu Island, Japan) contained more unknown actinomycete species than other sea areas, which eventually led to the discovery of akazamicin, a new cytotoxic aromatic polyketide from Nonomuraea [13] and akazaoxime

Natural products in the predatory defence of the filamentous fungal pathogen Aspergillus fumigatus

• Jana M. Boysen,
• Nauman Saeed and
• Falk Hillmann

Beilstein J. Org. Chem. 2021, 17, 1814–1827, doi:10.3762/bjoc.17.124

• , temperature and aeration, are known to regulate gliotoxin biosynthesis [115][119][120]. The biological activity of ETP’s like gliotoxin is mediated by the active disulfide bridge that targets vulnerable thiols or catalyses oxidative burst formation via redox cycling [78]. In previous studies, these cytotoxic

• also regulated by cluster specific transcriptional regulators TpcD/E [53]. Though the precise mechanism of action of trypacidin remains to be elucidated, it was shown to exhibit antiprotozoal, antiphagocytic and cytotoxic activities in vitro. Gauthier and colleagues (2012) have shown that in lung cells

• ][142]. In comparison to gliotoxin, we found only minor cytotoxic activities of fumagillin against the model amoebae D. discoideum [82]. It could still be conceivable that other amoeba could reveal higher sensitivity, but tests against the fungivorous amoeba P. aurantium were not yet conducted. DHN