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

• against the pathogenic fungal strains Aspergillus fumigatus and Candida albicans. The sensitivity of the organisms was assayed against the activity of tested compounds solutions (at 10 mg/mL concentration) using a modified agar well diffusion method with determination of the inhibition zone diameter in mm

• 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

• inhibition zone diameter using the agar well diffusion method. The structure–activity relationship (SAR) elaborated that piperazines with aliphatic groups on the nitrogen atom are more active than those with aromatic substituents against the fungus C. albicans. On the other hand, compounds comprising

Heteroleptic metallosupramolecular aggregates/complexation for supramolecular catalysis

• Prodip Howlader and
• Michael Schmittel

Beilstein J. Org. Chem. 2022, 18, 597–630, doi:10.3762/bjoc.18.62

• replicating their structures). The structural dissimilarity between the reactants and the subsequent product often contributes to the successful release of the product from the reaction vessel, thus, reducing product inhibition. Hence, it can be envisioned that the introduction of functionality within the

• product inhibition, and b) higher nanomechanical speed enlarges catalyst liberation. While the development of multicomponent rotors has started almost 20 years ago with seminal works by Shionoya [78][79][80] and Kume [81][82], the fascinating prospects of discrete nanomechanical motion was impressively

• geometrical or constitutional situation at the binding sites [92]. In a detailed recent study, the finding of a Hammett correlation in such nanorotors corroborated that a rate-determining dissociation at the rotator–metal binding interaction dictated the rotational speed [93]. Reducing Product Inhibition (RPI

Shift of the reaction equilibrium at high pressure in the continuous synthesis of neuraminic acid

• Jannis A. Reich,
• Miriam Aßmann,
• Kristin Hölting,
• Paul Bubenheim,
• Jürgen Kuballa and
• Andreas Liese

Beilstein J. Org. Chem. 2022, 18, 567–579, doi:10.3762/bjoc.18.59

• pressure on the inhibition by pyruvate was measured and is shown in Figure 9. The value for the inhibition constant is in the same order of magnitude as results of other groups, measured at ambient pressure (0.146 ± 0.019 mol/L [5]). Since the KI value changes with pressure (Table 4), the concentrations

• were kept constant and only the pressure was varied, resulting in the reactions rates shown in Figure 10 (left). By rearranging the rate expression and inserting the previously calculated kinetic parameters, the inhibition constant was calculated (Figure 10 (right)). The change in molar volume

• suggests a reduction in molar volume. The circular reactor setup allowed for easy sampling and enabled the analysis of the resulting progress curve. The findings for the epimerase indicate that some inconspicuous reactions, such as the inhibition by pyruvate, can be influenced by pressure. In both

Synthesis of sulfur karrikin bioisosteres as potential neuroprotectives

• Martin Pošta,
• Václav Zima,
• Lenka Poštová Slavětínská,
• Marika Matoušová and
• Petr Beier

Beilstein J. Org. Chem. 2022, 18, 549–554, doi:10.3762/bjoc.18.57

• oxygen with sulfur. In particular, we present synthetic procedures toward bioisosteres of karrikins with one or two sulfur heteroatoms incorporated into the core backbone together with evaluation of their biological activity in inhibition of acetylcholinesterase. Keywords: acetylcholinesterase

• brain of patients suffering with the Parkinson’s and the Alzheimer’s disease, respectively. Therefore, research is focused on the discovery of new drugs protecting acetylcholine and dopamine levels via inhibition of acetylcholinesterase (AChE) and monoamine oxidase (MAO). A promising source of such

• derivatives 27–30 were prepared from 8, 20, 21, and 26 using microwave heating with Lawesson’s reagent and HMDO (Scheme 6). Thionation provided the title compounds in good to high yields. Biochemical study – AchE inhibition The compounds were further tested for their ability to inhibit AChE in vitro [24

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

• ). The compounds with the highest antimalarial activity were 3b, 9e, 3a, and 10d with EC50 values of 0.2 ± 0.1 µM, 0.2 ± 0.04 µM, 0.3 ± 0.1 µM and 0.34 ± 0.01 µM, respectively. Unsubstituted 1-(7-chloroquinolinyl)pyrazole 11 was the only compound of this series that showed no inhibition up to a tested

Tosylhydrazine-promoted self-conjugate reduction–Michael/aldol reaction of 3-phenacylideneoxindoles towards dispirocyclopentanebisoxindole derivatives

• Sayan Pramanik and
• Chhanda Mukhopadhyay

Beilstein J. Org. Chem. 2022, 18, 469–478, doi:10.3762/bjoc.18.49

• , antitubercular, antidiabetic, antibacterial as well as cholinesterase inhibition (Figure 1) [3][4][5][6][7]. These unique chemical and biological characteristics of bispirooxindoles have stimulated the concentration of the synthetic community on developing new synthetic strategies towards their synthesis [8][9

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

• value of 19.03 μM. The investigation of anti-inflammatory activities of lobophysterols E–H with classic transgenic fluorescent zebrafish models (Figure 5) showed that compound 1 exhibited moderate activity, with an inhibition rate of 32% (20 μM). Conclusion In conclusion, four new steroids

A resorcin[4]arene hexameric capsule as a supramolecular catalyst in elimination and isomerization reactions

• Tommaso Lorenzetto,
• Fabrizio Fabris and
• Alessandro Scarso

Beilstein J. Org. Chem. 2022, 18, 337–349, doi:10.3762/bjoc.18.38

• after 24 h at 60 °C. Carvone isomerization was achieved at 60 °C for 24 h only combining the use of 10 mol % of capsule and 10 mol % of HBF4. Nevertheless, the reaction under identical conditions, but in the presence of 10 equiv of 3 as competitive guest, led only to a minimal inhibition of the reaction

• ), with quantitative yield after 20 h at 60 °C in the presence of 10 mol % of the capsule. The same reaction carried out with the capsule 16 and in the presence of 3 as competitive guest led to complete inhibition of the formation of the corresponding alkene (Figure 2D, Table 2, entry 2). This provides

Site-selective reactions mediated by molecular containers

• Rui Wang and
• Yang Yu

Beilstein J. Org. Chem. 2022, 18, 309–324, doi:10.3762/bjoc.18.35

• -stoichiometric quantities of hosts because of the product inhibition effect, which arose from the entropic disadvantage of the need for binding two reactant molecules [39][40][41][42][43]. In this particular report, when the octahedral cage host A was used, the Diels–Alder reaction of 9-hydroxymethylanthracene

Anomeric 1,2,3-triazole-linked sialic acid derivatives show selective inhibition towards a bacterial neuraminidase over a trypanosome trans-sialidase

• Peterson de Andrade,
• Sanaz Ahmadipour and
• Robert A. Field

Beilstein J. Org. Chem. 2022, 18, 208–216, doi:10.3762/bjoc.18.24

• sialic acid derivatives in good yields and high purity via copper-catalysed azide–alkyne cycloaddition (CuAAC, click chemistry) and evaluated their activity towards TcTS and neuraminidase. Surprisingly, the compounds showed practically no TcTS inhibition, whereas ca. 70% inhibition was observed for

• neuraminidase in relation to the analogues bearing hydrophobic substituents and ca. 5% for more polar substituents. These results suggest that polarity changes are less tolerated by neuraminidase due to the big difference in impact of hydrophobicity upon inhibition, thus indicating a simple approach to

• differences in sialidases that need to be addressed in order to achieve selective inhibition. Keywords: inhibition; neuraminidase; sialic acid; trans-sialidase; 1,2,3-triazole; Introduction Amongst the diversity of glycans present in living organisms, N-acetylneuraminic acid (Neu5Ac, sialic acid) is

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

• ], compounds 1−17 were evaluated for their inhibitory activities against LPS-induced nitric oxide (NO) production in RAW 264.7 mouse macrophages. All of them showed mild inhibitory activities with inhibition rates of 10–20% at a concentration of 50 μM (Table 2). Since coumarin derivatives were reported to have

Synthesis and late stage modifications of Cyl derivatives

• Phil Servatius and
• Uli Kazmaier

Beilstein J. Org. Chem. 2022, 18, 174–181, doi:10.3762/bjoc.18.19

• reactions. The chain length in 14 should generally be suitable for effective HDAC inhibition and the thioester moiety might act as a prodrug as described for the natural HDAC inhibitor largazole. Further investigations are currently in progress. Naturally occurring HDAC inhibitors. Naturally occurring HDAC

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

• Qiuxin Zhang Weiyi Tan Bing Xu Department of Chemistry, Brandeis University, 415 South Street, Waltham, MA 02454, USA 10.3762/bjoc.18.17 Abstract Here we report the synthesis and effect on the cell viability of pyrrole-conjugated phosphopeptides. Encouraged by the selective inhibition of cancer

• from 1, are largely compatible with HeLa cells, while 1, at 400 μM, significantly inhibits HeLa cells. These results suggest that morphological transition or extensive self-assembly triggered by enzymatic reactions likely is necessary for the inhibition of HeLa cells by EISA. This work, thus, provides

• investigated the physical properties (enzyme-catalyzed hydrogelation or supramolecular structural transformation) [62][70] and biological properties (cell viability, biostability, and cell-selective growth inhibition) [43][62] of the naphthylacetyl N-terminal-capped phosphopeptides. These studies have produced

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

• ][14], ddI (didanosine) [15], d4T (stavudine) [16][17], 3TC (lamivudine) [18][19] and AZT analogues were synthesized and evaluated towards inhibition of HIV reverse transcriptase (HIV RT). However, the toxic side effects associated with these molecules and development of drug-resistant viruses

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

• evaluated against their antioxidant activity and exhibited promising activity. Protein tyrosine phosphatase 1B (PTP1B) is essential in the dephosphorylation of the activated insulin receptor, and inhibition of this enzyme would be an excellent strategy for the treatment of type 2 diabetes. Ahn and co

• -workers [82] synthesized and evaluated several 1,2-naphthoquinones substituted at position C4 with alkyl- or arylamino groups for their inhibition of the PTP1B protein. Furthermore, to discover new effective anti-inflammatory and analgesic agents, Gouda and co-workers [83] synthesized various compounds in

• intracellular ROS and includes inhibition of tubulin polymerization (Scheme 9). Semicarbazides and thiosemicarbazides are substances used to identify aldehydes and ketones, are very versatile in the synthesis of heterocycles, and have several applications in the preparation of important drugs. Nucleophilic

Peptide stapling by late-stage Suzuki–Miyaura cross-coupling

• Hendrik Gruß,
• Rebecca C. Feiner,
• Ridhiwan Mseya,
• David C. Schröder,
• Michał Jewgiński,
• Kristian M. Müller,
• Rafał Latajka,
• Antoine Marion and
• Norbert Sewald

Beilstein J. Org. Chem. 2022, 18, 1–12, doi:10.3762/bjoc.18.1

• P5.2 of stapled peptide P5 shows an almost five times higher binding affinity (Kd = 258 ± 43 nM) compared to the linear reference peptide P6 (Kd = 1241 ± 162 nM, Figure 2) in the competitive FP assay. Isomer P5.1 was only isolated in insufficient amounts. Hence, a satisfactorily converging inhibition

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

• inhibition upon exposure to 4-anilinoquinazolines and compounds with the same scaffolds (erlotinib, gefitinib, and verubulin), and to positive control doxorubicin (MTT assay after treatment for 72 h). Supporting Information Supporting Information File 282: Experimental procedures, characterization data

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

• cellular targets known for antituberculosis drugs and all the different chemical structures (inhibition of cell wall synthesis, disruption of the plasma membrane, DNA-gyrase, etc.) the next work focused on determining the exact biological mechanism and docking studies could not be executed. Conclusion The

Highly stereocontrolled total synthesis of racemic codonopsinol B through isoxazolidine-4,5-diol vinylation

• Lukáš Ďurina,
• Anna Ďurinová,
• František Trejtnar,
• Ľuboš Janotka,
• Lucia Messingerová,
• Jana Doháňošová,
• Ján Moncol and
• Róbert Fischer

Beilstein J. Org. Chem. 2021, 17, 2781–2786, doi:10.3762/bjoc.17.188

• tubular cells HK2. (−)-Codonopsinol B (1) and its N-nor-methyl analogue 2; known inhibition activities against α-glucosidases from: (a) Bacillus stearothermophilus lyoph., (b) yeast [2]. Molecular structure of N-Cbz-protected pyrrolidine 12 confirmed by single-crystal X-ray crystallographic analysis

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

• ) showed a weak TPC2 inhibition at 100 µM. The nine other alkaloids did not significantly inhibit human TPC2, whereas tetrandrine and cepharanthine concentration-dependently blocked with IC50 values of 31/21 µM and 3.6/57 µM (Figure S2A and Figure S2B in Supporting Information File 1). Note that TPC2

• population indicates inhibition of P-glycoprotein. However, none of the tested compounds was able to retain calcein, indicating no P-glycoprotein inhibition. Tetrandrine served as positive control (Figure 5C). In line with that, none of the compounds restored sensitivity of VCR-R CEM cells to the P

Synthetic strategies toward 1,3-oxathiolane nucleoside analogues

• Umesh P. Aher,
• Dhananjai Srivastava,
• Girij P. Singh and
• Jayashree B. S

Beilstein J. Org. Chem. 2021, 17, 2680–2715, doi:10.3762/bjoc.17.182

• incorporated into the growing DNA strand. However, the absence of a 3'-hydroxy group prevents further strand elongation. The anticancer and antiviral activity of 2’,3’-dideoxynucleosides is mainly based on inhibition of DNA synthesis, either through the chain termination process or by competitive inhibition [3

• natural nucleosides with β-ᴅ-configuration in the carbohydrate part. These molecules are known to have a common HIV transcriptase inhibition mechanism, in which cytoplasmic enzymes progressively phosphorylate the analogues to 5'-triphosphates. This then competes with the naturally occurring nucleoside

• nucleic acid components. Therefore, it was assumed until recently that effective inhibition of the metabolic enzyme is only possible by ᴅ-nucleoside analogues, which have the stereochemistry of natural nucleosides. This was proved to be untrue when the antiviral activity of 1,3-oxathiolane nucleosides

Efficient synthesis of polyfunctionalized carbazoles and pyrrolo[3,4-c]carbazoles via domino Diels–Alder reaction

• Ren-Jie Fang,
• Chen Yan,
• Jing Sun,
• Ying Han and
• Chao-Guo Yan

Beilstein J. Org. Chem. 2021, 17, 2425–2432, doi:10.3762/bjoc.17.159

• used to treat joint pain and postoperative pain [6] (Figure 1). Ellipticine was considered to be based mainly on DNA intercalation and topoisomerase II inhibition [7]. Midostaurin and carvediol have been approved by the FDA for tumor therapy and treatment of congestive heart failure [8]. On the other

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

• human cancer cell lines and inhibition of the chemokine receptor CCR5, make them attractive synthetic targets. This review article highlights the recent synthetic methodologies and briefly summarizes their biological activities. Keywords: brevipolides; 5,6-dihydro-α-pyrone; Furukawa-modified Simmons

• all the centers of the stereochemical brevipolides but in the mirror image of the natural configuration. After sequential ring-closing metathesis, base-promoted olefin migration, and MEM removal, the ent-brevipolide H (ent-8) was obtained. This compound showed inhibition activity in the preliminary

• ]. These seven compounds, 1–7, were also evaluated for enzyme-based ELISA NF-κB and proteasome inhibition assays (Table 2, entries 1–7), but only brevipolide G (7) and brevipolide C (3) showed significant activities with ED50 values of 15.3 and 38.0 μM, respectively (Table 2, entries 7 and 3) [4]. Lastly

Synthesis and antimicrobial activity of 1H-1,2,3-triazole and carboxylate analogues of metronidazole

• Satya Kumar Avula,
• Syed Raza Shah,
• Khdija Al-Hosni,
• Muhammad U. Anwar,
• Rene Csuk,
• Biswanath Das and
• Ahmed Al-Harrasi

Beilstein J. Org. Chem. 2021, 17, 2377–2384, doi:10.3762/bjoc.17.154

• metronidazole derivatives. The antimicrobial (antifungal and antibacterial) activity of the prepared compounds was studied. All compounds (except 2 and 3) showed a potent inhibition rate of fungal growth as compared to control and metronidazole. The synthetic compounds also showed higher bacterial growth

• , fungal growth under compound 5e and compound 7c treatment was detected 2.8, 2.7 folds and 2.5, 2.6 folds less, respectively. All of the synthesized compounds except compounds 2 and 3 showed a higher inhibition rate of fungal growth as compared to the control and metronidazole (Figure 7 and Table 3). The

• inhibition zones were recorded after 7 days of treatment and compared with growth area of fungi growing in control conditions. Antibacterial activity To determine the bacterial growth inhibiting effects of compounds, bacterial OD600 was measured at different time points i.e., 12, 24, 36 and 48 h (Figure 8

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

• 17–19. The structural characterization of the new compounds was conducted based on the analysis of their spectroscopic and spectrometric data, and chemical methods. All isolated compounds were tested for their antineuroinflammatory and neuroprotective activities. Compound 14 showed inhibition effects