Nothing Special   »   [go: up one dir, main page]

You seem to have javascript disabled. Please note that many of the page functionalities won't work as expected without javascript enabled.
 
 
Sign in to use this feature.

Years

Between: -

Subjects

remove_circle_outline
remove_circle_outline
remove_circle_outline
remove_circle_outline
remove_circle_outline
remove_circle_outline
remove_circle_outline

Journals

Article Types

Countries / Regions

Search Results (109)

Search Parameters:
Keywords = indazole

Order results
Result details
Results per page
Select all
Export citation of selected articles as:
15 pages, 4054 KiB  
Article
A CD Study of a Structure-Based Selection of N-Heterocyclic Bis-Carbene Gold(I) Complexes as Potential Ligands of the G-Quadruplex-Forming Human Telomeric hTel23 Sequence
by Maria Marzano, Filippo Prencipe, Pietro Delre, Giuseppe Felice Mangiatordi, Gabriele Travagliante, Luisa Ronga, Gennaro Piccialli, Michele Saviano, Stefano D’Errico, Diego Tesauro and Giorgia Oliviero
Molecules 2024, 29(22), 5446; https://doi.org/10.3390/molecules29225446 - 19 Nov 2024
Viewed by 293
Abstract
Herein, we report the structure-based selection via molecular docking of four N-heterocyclic bis-carbene gold(I) complexes, whose potential as ligands for the hTel23 G-quadruplex structure has been investigated using circular dichroism (CD) spectroscopy, CD melting, and polyacrylamide gel electrophoresis (PAGE). The complex containing [...] Read more.
Herein, we report the structure-based selection via molecular docking of four N-heterocyclic bis-carbene gold(I) complexes, whose potential as ligands for the hTel23 G-quadruplex structure has been investigated using circular dichroism (CD) spectroscopy, CD melting, and polyacrylamide gel electrophoresis (PAGE). The complex containing a bis(1,2,3,4,6,7,8,9-octahydro-11H-11λ3-pyridazino[1,2-a]indazol-11-yl) scaffold induces a transition from the hybrid (3 + 1) topology to a prevalent parallel G-quadruplex conformation, whereas the complex featuring a bis(2-(2-acetamidoethyl)-3λ3-imidazo[1,5-a]pyridin-3(2H)-yl) moiety disrupted the original G-quadruplex structure. These results deserve particular attention in light of the recent findings on the pathological involvements of G-quadruplexes in neurodegenerative diseases. Full article
(This article belongs to the Special Issue G-quadruplexes in Chemical Biology and Drug Discovery)
Show Figures

Graphical abstract

Graphical abstract
Full article ">Figure 1
<p>The structure of Auranofin.</p>
Full article ">Figure 2
<p>The structures of the NHC–gold(I) complexes <b>1</b>–<b>17</b> selected by the molecular docking simulations. The numbering is in parentheses according to Porchia et al. [<a href="#B13-molecules-29-05446" class="html-bibr">13</a>].</p>
Full article ">Figure 3
<p>Panel (<b>A</b>): Chart showing the G-score (y-axis) calculated for each complex (x-axis). The orange dashed line represents the reference G-score of complex <b>5</b>. The red asterisks represent the selected complexes <b>4</b>, <b>9</b>, <b>12</b>, and <b>16</b>. Panel (<b>B</b>): Table summarizing the calculated G-scores for each complex. The complex marked in orange corresponds to complex <b>5</b>, while the complexes marked in red represent complexes <b>4</b>, <b>9</b>, <b>12</b>, and <b>16</b>.</p>
Full article ">Figure 4
<p>Panel (<b>A</b>): X-ray solved hTel23 G-quadruplex structure extracted from the Protein Data Bank (PDB code: 6H5R). Panels (<b>B</b>–<b>E</b>): Top-scoring docking poses within the hTel23 G-quadruplex (PDB: 6H5R) of complexes <b>4</b>, <b>9</b>, <b>12</b>, and <b>16</b>, respectively. For clarity, only polar hydrogen atoms are shown. Important residues are rendered as sticks, while the hTel23 G-quadruplex is represented as cartoon. π−π interactions are depicted as blue lines.</p>
Full article ">Figure 5
<p>CD spectra of hTel23 G-quadruplex in the absence (<b>A</b>) and presence of increasing molar equivalents of complexes <b>4</b> (<b>B</b>), <b>9</b> (<b>C</b>), <b>12</b> (<b>D</b>), and <b>16</b> (<b>E</b>). CD melting spectra of hTel23 G-quadruplex in the absence and presence of 5 equiv. of complexes <b>4</b>, <b>9</b>, <b>12</b>, and <b>16</b> (<b>F</b>). CD spectra were acquired in a 90 mmol/L K<sup>+</sup> phosphate-buffered solution (pH = 7.3). CD melting experiments were acquired by monitoring the CD value of the higher positive Cotton effect in the temperature range of 5–90 °C in a 90 mmol/L K<sup>+</sup> phosphate-buffered solution (pH = 7.3).</p>
Full article ">Figure 6
<p>CD spectra of the hTel23 G-quadruplex in the presence of increasing molar equivalents of complexes <b>12</b> (Panel <b>A</b>) and <b>16</b> (Panel <b>B</b>). The insets show the corresponding titration curves: for complex <b>12</b>, the change in ellipticity was calculated at 272 nm (black squares) and 290 nm (red circles); for complex <b>16</b>, the change in ellipticity was calculated at 290 nm. All curves were fitted using non-linear regression (Hill fit for the CD signal at 272 nm and Hill1 fit for the CD signal at 290 nm) in OriginPro2018.</p>
Full article ">Figure 7
<p>Non-denaturing PAGE prepared in TBE buffer supplemented with 30 mmol/L KCl. hTel23 G-quadruplex alone at concentration of 20 µmol/L (lane 1); hTel23 + 5 equiv. of complex <b>16</b> (lane 2); hTel23 + 5 equiv. of complex <b>12</b> (lane 3).</p>
Full article ">Scheme 1
<p>Reagents and conditions: (i) (CH<sub>2</sub>O)<sub>n</sub>, EtOH, r.t., 4 h, then 2-Pyridinecarboxaldehyde, HCl, EtOH, r.t., 16 h; (ii) KPF<sub>6</sub>, H<sub>2</sub>O, r.t., 1 h; (iii) Ag<sub>2</sub>O, 10% MeOH in CH<sub>2</sub>Cl<sub>2</sub>, r.t., 16 h; (iv) AuClS(CH<sub>3</sub>)<sub>2</sub>, LiBr, 10% MeOH in CH<sub>2</sub>Cl<sub>2</sub>, r.t., 5 h.</p>
Full article ">
19 pages, 2581 KiB  
Article
Design, Synthesis, and Evaluation of EA-Sulfonamides and Indazole-Sulfonamides as Promising Anticancer Agents: Molecular Docking, ADME Prediction, and Molecular Dynamics Simulations
by Nassima Saghdani, Nabil El Brahmi, Abdelmoula El Abbouchi, Rachid Haloui, Souad Elkhattabi, Gérald Guillaumet and Saïd El Kazzouli
Chemistry 2024, 6(6), 1396-1414; https://doi.org/10.3390/chemistry6060083 - 9 Nov 2024
Viewed by 461
Abstract
New EA-sulfonamides and indazole-sulfonamides were synthesized, characterized, and evaluated for their anticancer activities. The target compound structures were elucidated using various spectroscopic techniques such as NMR-{1H and 13C}, infrared spectroscopy, and high-resolution mass spectrometry. The anticancer activities of the [...] Read more.
New EA-sulfonamides and indazole-sulfonamides were synthesized, characterized, and evaluated for their anticancer activities. The target compound structures were elucidated using various spectroscopic techniques such as NMR-{1H and 13C}, infrared spectroscopy, and high-resolution mass spectrometry. The anticancer activities of the novel compounds were evaluated against four human cancer cell lines, namely A-549, MCF-7, Hs-683, and SK-MEL-28 as well as the normal cell line HaCaT, using 5-fluorouracil and etoposide as reference drugs. Among the tested compounds, 9, 10, and 13 exhibited potent anticancer activities which are better than or similar to the reference compounds 5-fluorouracil and etoposide, against the A-549, MCF-7, and Hs-683 cancer cell lines, with IC50 values ranging from 0.1 to 1 μM. Molecular docking studies of compounds 9, 10, and 13 showed a strong binding with selected protein kinase targets, which are linked to the tested cancer types. Furthermore, the analysis of the molecular dynamics simulation results demonstrated that compound 9 exhibits significant stability when bound to both JAK3 and ROCK1 kinases. This new compound has the potential to be developed as a novel therapeutic agent against various cancers. Full article
(This article belongs to the Special Issue Cutting-Edge Studies of Computational Approaches in Drug Discovery)
Show Figures

Graphical abstract

Graphical abstract
Full article ">Figure 1
<p>Selectivity index of <b>9</b>, <b>10</b>, <b>13</b>, and <b>18</b>.</p>
Full article ">Figure 2
<p>Molecular redocking of co-crystallized ligands within the kinases concerned: original (red) and re-docked (blue).</p>
Full article ">Figure 3
<p>RMSD plots for (<b>a</b>) 4Z16, free and complexed with <b>9</b>; and (<b>b</b>) 6E9W, free and complexed with <b>9</b>.</p>
Full article ">Figure 4
<p>RMSF plots for (<b>a</b>) 4Z16, free and complexed with <b>9</b>; and (<b>b</b>) 6E9W, free and complexed with <b>9</b>.</p>
Full article ">Figure 5
<p>Histogram of interactions between ligand <b>9</b> and JAK3 (4Z16) and ROCK1 (6E9W) kinases for 100 ns: (<b>a</b>) <b>9</b> with 4Z16, and (<b>b</b>) <b>9</b> with 6E9W.</p>
Full article ">Scheme 1
<p><b>EA</b> and indazole derivatives bearing a sulfonamide moiety.</p>
Full article ">Scheme 2
<p>Synthesis of new indazole-sulfonamide derivatives <b>1</b>, <b>2</b>, and <b>4</b>–<b>8</b>.</p>
Full article ">Scheme 3
<p>Synthesis of new <b>EA</b>-sulfonamide derivatives <b>9</b>, <b>10</b>, <b>13</b>, and <b>18</b>–<b>20</b>.</p>
Full article ">
25 pages, 5904 KiB  
Article
In Vitro Evaluation of New 5-Nitroindazolin-3-one Derivatives as Promising Agents against Trypanosoma cruzi
by Josué Pozo-Martínez, Vicente J. Arán, Matías Zúñiga-Bustos, Sebastián Parra-Magna, Esteban Rocha-Valderrama, Ana Liempi, Christian Castillo, Claudio Olea-Azar and Mauricio Moncada-Basualto
Int. J. Mol. Sci. 2024, 25(20), 11107; https://doi.org/10.3390/ijms252011107 - 16 Oct 2024
Viewed by 666
Abstract
Chagas disease is a prevalent health problem in Latin America which has received insufficient attention worldwide. Current treatments for this disease, benznidazole and nifurtimox, have limited efficacy and may cause side effects. A recent study proposed investigating a wide range of nitroindazole and [...] Read more.
Chagas disease is a prevalent health problem in Latin America which has received insufficient attention worldwide. Current treatments for this disease, benznidazole and nifurtimox, have limited efficacy and may cause side effects. A recent study proposed investigating a wide range of nitroindazole and indazolone derivatives as feasible treatments. Therefore, it is proposed that adding a nitro group at the 5-position of the indazole and indazolone structure could enhance trypanocidal activity by inducing oxidative stress through activation of the nitro group by NTRs (nitroreductases). The study results indicate that the nitro group advances free radical production, as confirmed by several analyses. Compound 5a (5-nitro-2-picolyl-indazolin-3-one) shows the most favorable trypanocidal activity (1.1 ± 0.3 µM in epimastigotes and 5.4 ± 1.0 µM in trypomastigotes), with a selectivity index superior to nifurtimox. Analysis of the mechanism of action indicated that the nitro group at the 5-position of the indazole ring induces the generation of reactive oxygen species (ROS), which causes apoptosis in the parasites. Computational docking studies reveal how the compounds interact with critical residues of the NTR and FMNH2 (flavin mononucleotide reduced) in the binding site, which is also present in active ligands. The lipophilicity of the studied series was shown to influence their activity, and the nitro group was found to play a crucial role in generating free radicals. Further investigations are needed of derivatives with comparable lipophilic characteristics and the location of the nitro group in different positions of the base structure. Full article
(This article belongs to the Section Biochemistry)
Show Figures

Figure 1

Figure 1
<p>5-Nitroindazolin-3-ones with trypanocidal activity previously described [<a href="#B15-ijms-25-11107" class="html-bibr">15</a>,<a href="#B18-ijms-25-11107" class="html-bibr">18</a>] and structures of nifurtimox and benznidazole.</p>
Full article ">Figure 2
<p>5-Nitroindazolin-3-ones and other 5-nitroindazole derivatives studied in this work.</p>
Full article ">Figure 3
<p>Cyclic voltammogram of compound <b>3b</b>, recorded at different scan rates between 0.1 and 2.0 V/s.</p>
Full article ">Figure 4
<p>(<b>A</b>) Cyclic voltammogram of compound <b>19</b> with a potential sweep between −2.0 and 0.0 V and sweep speeds between 0.1 and 2.0 V/s. (<b>B</b>) Cyclic voltammogram using a potential range between −1.8 and −0.9 V and sweep speeds between 0.1 and 2.0 V/s. (<b>C</b>) Cyclic voltammogram using a speed of 2.0 V/s: (i) the first black line without NaOH; (ii) the red line in the presence of 30 mM NaOH.</p>
Full article ">Figure 5
<p>Experimental (black) and WimSIM (blue) simulated the ESR spectrum of (<b>A</b>) compound <b>5a</b>, (<b>B</b>) compound <b>10</b>, and (<b>C</b>) compound <b>23</b> at room temperature in DMSO.</p>
Full article ">Figure 5 Cont.
<p>Experimental (black) and WimSIM (blue) simulated the ESR spectrum of (<b>A</b>) compound <b>5a</b>, (<b>B</b>) compound <b>10</b>, and (<b>C</b>) compound <b>23</b> at room temperature in DMSO.</p>
Full article ">Figure 6
<p>(<b>A</b>). Percentage of SYTOX Green probe incorporation of the most active compounds on <span class="html-italic">T. cruzi</span> trypomastigotes. (<b>B</b>). Percentage of SYTOX Green probe incorporation of the most active compounds on RAW 264.7 cells. (<b>C</b>). Percentage of TMRM probe incorporation by variation of the mitochondrial membrane potential on <span class="html-italic">T. cruzi</span> trypomastigote. (<b>D</b>). Percentage of ATP levels in <span class="html-italic">T. cruzi</span> trypomastigotes by the effect of the compounds with the highest trypanocidal activity. The significant difference compared to the control (one-way ANOVA with Dunnett post-test, ****: <span class="html-italic">p</span> ≤ 0.001; **: <span class="html-italic">p</span> ≤ 0.05; *: <span class="html-italic">p</span> ≤ 0.1). ns: non significative variation.</p>
Full article ">Figure 7
<p>Increase in fluorescence as a function of time by generation of intracellular ROS in trypomastigotes of <span class="html-italic">T. cruzi</span>.</p>
Full article ">Figure 8
<p>Spectra of the spin adducts generated in trypomastigote forms of <span class="html-italic">T. cruzi</span> (Dm28c) at room temperature. (<b>A</b>) Spectrum recorded with trypomastigotes incubated with compound <b>5a</b> and DMPO, marked with (*), (↓), and (+), radicals centered on carbon, DMPOOX, and hydroxyl radical, respectively. (<b>B</b>) Spectrum recorded in trypomastigotes with the DMPO spin trap.</p>
Full article ">Figure 9
<p>(<b>A</b>) Structure of modeled <span class="html-italic">Tc</span>NTR receptor including two monomers (chain A in red and chain B in blue, respectively). (<b>B</b>) Superposition of FMN binding mode into ecNTR receptor and <span class="html-italic">Tc</span>NTR docking result. (<b>C</b>) Ligand interaction diagram of FMNH<sub>2</sub> and <span class="html-italic">Tc</span>NTR binding site.</p>
Full article ">Figure 10
<p>Ligand interaction maps of (<b>A</b>) <b>5a</b>, (<b>B</b>) <b>7</b>, (<b>C</b>) <b>1</b>, and active ligands (<b>D</b>) NFX, (<b>E</b>) <b>2a,</b> and (<b>F</b>) <b>2b</b> into the <span class="html-italic">Tc</span>NTR binding site predicted through docking calculations (carbons are in green). FMNH<sub>2</sub> is depicted in the figure with gray carbons, while chains A and B of <span class="html-italic">Tc</span>NTR are colored red and blue, respectively.</p>
Full article ">Figure 11
<p>Correlations between (<b>A</b>) lipophilicity and trypanocidal activity on the trypomastigote form of the 5-nitroindazolin-3-one series, the halogenated compounds that did not correlate are indicated in a circle, (<b>B</b>) reduction potentials (Epc) and trypanocidal activity on the trypomastigote form of the 5-nitroindazolin-3-one series, and (<b>C</b>) interaction energy with <span class="html-italic">Tc</span>NTR and trypanocidal activity on the trypomastigote form of the 5-nitroindazolin-3-one series.</p>
Full article ">Scheme 1
<p>Synthesis of 5-nitroindazolin-3-ones <b>7</b>–<b>18</b>. Reagents and conditions: Method A, for <b>7</b>–<b>18</b>: MeI, K<sub>2</sub>CO<sub>3</sub>, DMF, RT, overnight, 95–98%. Method B, for <b>8</b>–<b>12</b>, <b>14</b>, and <b>17</b>: substituted benzyl bromide, DMF, 150 °C, 4 h, 89–96%.</p>
Full article ">Scheme 2
<p>Proposed reduction mechanism for both 5-nitroindazole and 5-nitroindazolinone series with labile protons.</p>
Full article ">
15 pages, 2968 KiB  
Article
3-Alkoxy-1-Benzyl-5-Nitroindazole Derivatives Are Potent Antileishmanial Compounds
by Niurka Mollineda-Diogo, Sergio Sifontes-Rodríguez, María Magdalena Aguirre-García, Alma Reyna Escalona-Montaño, Teresa Espinosa-Buitrago, Ricardo Mondragón-Flores, Mónica Edith Mondragón-Castelán, Alfredo Meneses-Marcel, Ofelia Pérez-Olvera, Daniel Andrés Sánchez-Almaraz, Yunierkis Perez-Castillo and Vicente Arán-Redó
Int. J. Mol. Sci. 2024, 25(19), 10582; https://doi.org/10.3390/ijms251910582 - 1 Oct 2024
Viewed by 626
Abstract
Indazoles have previously been identified as molecules with antiprotozoal activity. In this study, we evaluate the in vitro activity of thirteen 3-alkoxy-1-benzyl-5-nitroindazole derivatives (series D) against L. amazonensis, L. infantum, and L. mexicana. In vitro, cytotoxicity against mouse peritoneal macrophages and [...] Read more.
Indazoles have previously been identified as molecules with antiprotozoal activity. In this study, we evaluate the in vitro activity of thirteen 3-alkoxy-1-benzyl-5-nitroindazole derivatives (series D) against L. amazonensis, L. infantum, and L. mexicana. In vitro, cytotoxicity against mouse peritoneal macrophages and growth inhibitory activity in promastigotes were evaluated for all compounds, and those showing adequate activity and selectivity were tested against intracellular amastigotes. Transmission and scanning electron microscopy were employed to study the effects of 3-alkoxy-1-benzyl-5-nitroindazole and 2-benzyl-5-nitroindazolin-3-one derivatives on promastigotes of L. amazonensis. Compounds NV6 and NV8 were active in the two life stages of the three species, with the latter showing the best indicators of activity and selectivity. 3-alkoxy-1-benzyl-5-nitroindazole derivatives (series D) showed in vitro activity comparable to that of amphotericin B against the promastigote stage of Leishmania spp. Two compounds were also found to be active the amastigote stage. Electron microscopy studies confirmed the antileishmanial activity of the indazole derivatives studied and support future research on this family of compounds as antileishmanial agents. Full article
(This article belongs to the Special Issue Advances in Therapeutics against Eukaryotic Pathogens)
Show Figures

Figure 1

Figure 1
<p>Series of 5-nitroindazolin-3-one structures evaluated against <span class="html-italic">T. cruzi</span>.</p>
Full article ">Figure 2
<p>New series of compounds designed for inhibition studies of <span class="html-italic">T. cruzi</span>.</p>
Full article ">Figure 3
<p>Growth curves of the promastigotes of the three species of <span class="html-italic">Leishmania</span>.</p>
Full article ">Figure 4
<p>Scanning electron microscopy of NV8 (IC<sub>50</sub> = 0.007 μM, ½ IC<sub>50</sub> = 0.0035 μM, ¼ IC<sub>50</sub> = 0.0017 μM) and VATR 131 (IC<sub>50</sub> = 2.13 μM, ½ IC<sub>50</sub> = 1.065 μM, ¼ IC<sub>50</sub> = 0.53 μM) against promastigotes of <span class="html-italic">L. amazonensis</span>. Scale bar = 0.5 µm.</p>
Full article ">Figure 5
<p>Transmission electron microscopy of <span class="html-italic">L. amazonensis</span> promastigotes after 72 h of incubation: Control Group (<b>A</b>), DMSO 0.1% (<b>B</b>), IC<sub>50</sub> = 0.007 μM (<b>C</b>–<b>E</b>), ½ IC<sub>50</sub> = 0.0035 μM (<b>F</b>–<b>H</b>), and ¼ IC<sub>50</sub> = 0.0017 μM (<b>I</b>–<b>K</b>) of NV8 compound. Scale bar = 0.5 µm. Flagellum (F), Flagellar Pocket (FP), Kinetoplast (K), Nucleus (N), Mitochondria (M), Cytoplasmic Vacuoles (V), Dead Parasites (black star), Deformed Flagellar Pocket (*), Dead Parasites with extruded cytoplasm (+) and Cytosolic Granules (CG).</p>
Full article ">Figure 6
<p>Transmission electron microscopy of <span class="html-italic">L. amazonensis</span> promastigotes after 72 h of incubation with ¼ IC<sub>50</sub> = 0.53 μM (<b>A</b>,<b>B</b>), ½ IC<sub>50</sub> = 1.065 μM (<b>C</b>,<b>D</b>) and IC<sub>50</sub> = 2.13 μM (<b>E</b>,<b>F</b>) of compound VATR 131. Scale bar = 1 µm.</p>
Full article ">
18 pages, 5510 KiB  
Article
Classification of Mass Spectral Data to Assist in the Identification of Novel Synthetic Cannabinoids
by Kristopher C. Evans-Newman, Garion L. Schneider and Nuwan T. Perera
Molecules 2024, 29(19), 4646; https://doi.org/10.3390/molecules29194646 - 30 Sep 2024
Viewed by 618
Abstract
Detection and characterization of newly synthesized cannabinoids (NSCs) is challenging due to the lack of availability of reference standards and chemical data. In this study, a binary classification system was developed and validated using partial least square discriminant analysis (PLS-DA) by utilizing readily [...] Read more.
Detection and characterization of newly synthesized cannabinoids (NSCs) is challenging due to the lack of availability of reference standards and chemical data. In this study, a binary classification system was developed and validated using partial least square discriminant analysis (PLS-DA) by utilizing readily available mass spectral data of known drugs to assist in the identification of previously unknown NCSs. First, a binary classification model was developed to discriminate cannabinoids and cannabinoid-related compounds from other drug classes. Then, a classification model was developed to discriminate classical (THC-related) from synthetic cannabinoids. Additional models were developed based on the most abundant functional groups including core groups such as indole, indazole, azaindole, and naphthoylpyrrole, as well as head and tail groups including 4-fluorobenzyl (FUB) and 5-Fluoropentyl (5-F). The predictive ability of these models was tested via both cross-validation and external validation. The results show that all models developed are highly accurate. Additionally, latent variables (LVs) of each model provide useful mass to charge (m/z) for discrimination between classes, which further facilitates the identification of different functional groups of previously unknown drug molecules. Full article
(This article belongs to the Section Analytical Chemistry)
Show Figures

Figure 1

Figure 1
<p>Structure of JWH-018 demonstrating the major groups of a typical synthetic cannabinoid.</p>
Full article ">Figure 2
<p>PCA score plot of cannabinoids (Red) and other drug classes (Green).</p>
Full article ">Figure 3
<p>General overview of the binary classification system.</p>
Full article ">Figure 4
<p>The Results of PLS-DA analysis of cannabinoids and other drugs using GA as a feature selection method: (<b>a</b>) PLS-DA score plot of the training set; (<b>b</b>) PLS-DA score plot of the prediction set; (<b>c</b>) LV1 with the weights. Here, the x-axis is the <span class="html-italic">m</span>/<span class="html-italic">z</span> ratio.</p>
Full article ">Figure 5
<p>The Results of PLS-DA analysis of synthetic cannabinoids and classical cannabinoids: (<b>a</b>) score plot of the training set and (<b>b</b>) prediction set without using variable selection methods; (<b>c</b>) score plot of the training set and (<b>d</b>) prediction set with using GA as the variable selection method. (<b>e</b>) LV1 of the weights for the model developed using GA as the variable selection method.</p>
Full article ">Figure A1
<p>Functional groups of primary interest in the current study.</p>
Full article ">Figure A2
<p>Dendrogram showing the results of HCA. Green: mostly classical cannabinoids, Red: mostly naphthyl head group containing cannabinoids, Blue: mostly indole core containing cannabinoids, and Yellow: mostly azaindole/indazole core containing cannabinoids.</p>
Full article ">Figure A3
<p>Formation of fragments of interest for indole and indazole core groups: (<b>a</b>) Indole core group with pentyl tail group. (<b>b</b>) Indazole core group with pentyl tail group. (<b>c</b>) Indole core group with 5-fluoropentyl tail group. (<b>d</b>) Indazole core group with 5-fluoropentyl tail group.</p>
Full article ">Figure A4
<p>Formation of fragments of interest for cannabinoids containing naphthyl head group: (<b>a</b>) with indole, (<b>b</b>) with indazole core groups.</p>
Full article ">Figure A5
<p>Formation of fragments of interest for cannabinoids containing FUB tail group.</p>
Full article ">Figure A6
<p>Formation of fragments of interest for cannabinoids containing 5-fluoropentyl tail group: (<b>a</b>) with indole, (<b>b</b>) with indazole core groups.</p>
Full article ">
10 pages, 3901 KiB  
Communication
An Alternative Method for Synthesizing N,2,3-Trimethyl-2H-indazol-6-amine as a Key Component in the Preparation of Pazopanib
by Thi Thanh Cham Bui, Hue Linh Luu, Thi Thanh Luong, Thi Ngoc Nguyen, Nguyet Suong Huyen Dao, Van Giang Nguyen, Dinh Luyen Nguyen, Nguyen Trieu Trinh and Van Hai Nguyen
Chemistry 2024, 6(5), 1089-1098; https://doi.org/10.3390/chemistry6050063 - 19 Sep 2024
Viewed by 858
Abstract
Due to its application as an anti-cancer drug, pazopanib (1) has attracted the interest of many researchers, and several studies on pazopanib synthesis have been reported over the years. This paper provides a novel route for synthesizing N,2,3-trimethyl-2H-indazol-6-amine [...] Read more.
Due to its application as an anti-cancer drug, pazopanib (1) has attracted the interest of many researchers, and several studies on pazopanib synthesis have been reported over the years. This paper provides a novel route for synthesizing N,2,3-trimethyl-2H-indazol-6-amine (5), which is a crucial building block in the synthesis of pazopanib from 3-methyl-6-nitro-1H-indazole (6). By alternating between the reduction and two methylation steps, compound 5 was obtained in a yield comparable (55%) to what has been reported (54%). It is noteworthy that the last step of N2-methylation also yielded N,N,2,3-tetramethyl-2H-indazol-6-amine (5′) as a novel compound. Furthermore, the data presented in this paper can serve as a valuable resource for future research aimed at further refining the process of synthesizing pazopanib and its derivatives. Full article
(This article belongs to the Section Medicinal Chemistry)
Show Figures

Graphical abstract

Graphical abstract
Full article ">Figure 1
<p>Structural components (<b>2</b>, <b>3</b>, <b>4</b>, <b>5</b>) of pazopanib (<b>1</b>).</p>
Full article ">Scheme 1
<p>Diagram of synthesis of pazopanib hydrochloride from compound <b>4</b> or <b>5</b>.</p>
Full article ">Scheme 2
<p>Approaches for preparing compound <b>5</b> from 3-methyl-6-nitro-1<span class="html-italic">H</span>-indazole (<b>6</b>).</p>
Full article ">Scheme 3
<p>Method of synthezing compound <b>5</b> starting from compound <b>6</b>.</p>
Full article ">Scheme 4
<p>The methylation of compound <b>9</b> by TMOF (ratio of TMOF: compound <b>9</b> as 6.2:1) in concentrated H<sub>2</sub>SO<sub>4</sub> generated a mixture of target compound <b>5</b> and by-product <b>5′</b>, whose structure has not been reported in the literature. Compound <b>5″</b> was not isolated. Switching the ratio of TMOF: compound <b>9</b> to 4:1 facilitated the isolation of product <b>5</b> as the sole product at 73%.</p>
Full article ">Scheme 5
<p>The probable mechanism by which compound <b>9</b> is methylated by TMOF in an acidic condition.</p>
Full article ">
11 pages, 4146 KiB  
Communication
Synthesis and Characterization of Novel Indazole–Sulfonamide Compounds with Potential MAPK1 Inhibitory Activity for Cancer Treatment
by Nassima Saghdani, Abdelali Chihab, Nabil El Brahmi and Saïd El Kazzouli
Molbank 2024, 2024(3), M1858; https://doi.org/10.3390/M1858 - 26 Jul 2024
Viewed by 790
Abstract
Indazoles are a very important group of nitrogen-containing heterocycles with a wide range of biological and medicinal applications. These properties make them highly attractive for drug development, particularly when combined with sulfonamides to enhance their medicinal potential. In this work, we synthesized an [...] Read more.
Indazoles are a very important group of nitrogen-containing heterocycles with a wide range of biological and medicinal applications. These properties make them highly attractive for drug development, particularly when combined with sulfonamides to enhance their medicinal potential. In this work, we synthesized an indazole-based sulfonamide, namely the 1-((2-chloro-5-methoxyphenyl)sulfonyl)-5-nitro-1H-indazole (3). The reduction of the nitro group of 5-nitroindazole (1) to its corresponding amine was also performed to yield compound (4). Both compounds’ structures were elucidated using various spectroscopic techniques such as 1H NMR, 13C NMR, infrared (IR), and high-resolution mass spectrometry (HRMS). Our molecular docking studies suggest that compounds (3) and (4) have a strong affinity for MAPK1, indicating their potential as cancer treatments. Full article
(This article belongs to the Collection Heterocycle Reactions)
Show Figures

Figure 1

Figure 1
<p><sup>1</sup>H NMR spectrum of compound (<b>3</b>).</p>
Full article ">Figure 2
<p>NOESY NMR spectrum of compound (<b>3</b>).</p>
Full article ">Figure 3
<p><sup>1</sup>H NMR spectrum of compound (<b>4</b>).</p>
Full article ">Figure 4
<p>IR spectra of compound (<b>3</b>).</p>
Full article ">Figure 5
<p>IR spectra of compound (<b>4</b>).</p>
Full article ">Figure 6
<p>3D and 2D interactions of compound (<b>3</b>) in the MAPK1 active site.</p>
Full article ">Figure 7
<p>3D and 2D interactions of compound (<b>4</b>) in the MAPK1 active site.</p>
Full article ">Scheme 1
<p>Synthesis of compounds (<b>3</b>) and (<b>4</b>).</p>
Full article ">
25 pages, 4482 KiB  
Article
Indazole–Quinolone Hybrids as Anti-Virulence Agents against Pseudomonas aeruginosa
by Marie Hanot, Marine Duplantier, Céline Dalle, Yani Ren, Sophie Da Nascimento, Jean-Paul Becker, Nicolas Taudon, Elodie Lohou and Pascal Sonnet
Drugs Drug Candidates 2024, 3(3), 512-536; https://doi.org/10.3390/ddc3030030 - 19 Jul 2024
Viewed by 1111
Abstract
Antibiotic resistance is a critical public health issue. Among the multi-drug resistant microorganisms in question, Pseudomonas aeruginosa has been designated by the WHO as a priority threat. Its virulence is orchestrated through quorum sensing (QS). This sophisticated communication network relies on the release [...] Read more.
Antibiotic resistance is a critical public health issue. Among the multi-drug resistant microorganisms in question, Pseudomonas aeruginosa has been designated by the WHO as a priority threat. Its virulence is orchestrated through quorum sensing (QS). This sophisticated communication network relies on the release and perception of autoinducers acting as population density indicators. Therefore, the interest of a quorum silencing pharmacological approach has unfolded to quench bacterial pathogenicity without impairing growth. In this article, we reported the development of a family of indazole–quinolone hybrids as anti-virulence agents. These new biaromatic compounds were designed as potential specific QS quenchers against P. aeruginosa. Our transdisciplinary research methodology included their synthesis using palladocatalyzed cross-coupling reactions, as well as their in silico physicochemical and in vitro biological evaluation. The hit 7-chloro-2-indazolyl-4-quinolone Ie shows a promising anti-biofilm and anti-pyocyanin efficiency (35% inhibition at 25 µM and 35% inhibition at 100 µM, respectively) without an anti-pseudomonal bacteriostatic effect. It also demonstrated a moderate eukaryotic cytotoxicity. Its anti-QS properties have been investigated using metabolomic and molecular modelling studies. Full article
(This article belongs to the Section Medicinal Chemistry and Preliminary Screening)
Show Figures

Figure 1

Figure 1
<p>Design strategy of the new indazole–quinolone hybrids.</p>
Full article ">Figure 2
<p>Evaluation of biofilm production on <span class="html-italic">P. aeruginosa</span> PAO1 strain. Quantitative analysis via crystal violet staining following 24 h growth in the presence or absence of tested products at different concentrations. Bars represent the mean ± SD of at least three independent experiments performed in triplicate. * <span class="html-italic">p</span> &lt; 0.05 and ** <span class="html-italic">p</span> &lt; 0.01 and *** <span class="html-italic">p</span> &lt; 0.001 vs. control (Mann–Whitney’s test: <span class="html-italic">p</span> values &lt; 0.05 were considered significant).</p>
Full article ">Figure 3
<p>Evaluation of pyocyanin secretion on the <span class="html-italic">P. aeruginosa</span> PAO1 strain. Measurement of the pigment concentration using UV/Vis spectrometry after 48 h growth in the presence or absence of tested products at different concentrations. Bars represent the mean ± SD of at least three independent experiments performed in triplicate. * <span class="html-italic">p</span> &lt; 0.05 and ** <span class="html-italic">p</span> &lt; 0.01 and *** <span class="html-italic">p</span> &lt; 0.001 vs. control (Mann–Whitney’s test: <span class="html-italic">p</span> values &lt; 0.05 were considered significant).</p>
Full article ">Figure 4
<p>Evaluation of HHQ, PQS, pyocyanin and odDHL secretion by the <span class="html-italic">P. aeruginosa</span> PA14 strain. Measurement of the metabolite rates in the pseudomonal culture supernatant using UPLC/HRMS after 24 h growth in the presence or absence of tested products at 200 µM. A targeted raw data analysis was applied to evaluate the signal of four QS-related metabolites. Extracted signals were normalized with the mean of controls and were reported as a percentage. An analysis of variance (ANOVA) followed by Dunnett’s test were utilized to highlight the differences after <span class="html-italic">P. aeruginosa</span> treatment with either compound <b>Id</b> or <b>Ie</b>. The bars represent the mean ± SD of one experiment performed in triplicate. * <span class="html-italic">p</span> &lt; 0.05 and ** <span class="html-italic">p</span> &lt; 0.001 vs. control (ANOVA and Dunnett’s test: <span class="html-italic">p</span> values &lt; 0.05 were considered significant).</p>
Full article ">Figure 5
<p>Molecular docking study in the PqsR autoinduction site. (<b>A</b>). Topology diagrams of the PQS-binding hydrophobic domain of PqsR (pockets P<sub>1</sub> and P<sub>2</sub>) interacting with <b>QSI-2</b> (in yellow) or <b>QSI-5</b> (<b>M64</b> in cyan) compared to <b>Ie</b> (in purple). (<b>A<sub>1</sub></b>) The docking pose of <b>Ie</b> is superimposed on the co-crystallized ligand <b>QSI-2</b> bound to PqsR. This protein model used for the molecular docking procedure was collected from the RCSB Protein Data Bank (PDB of Research Collaboratory for Structural Bioinformatics) under the access code 4JVI. (<b>A<sub>2</sub></b>) The co-crystallized structure of PqsR with the bound ligand <b>M64</b> (PDB code 6B8A) is overlaid by the PqsR crystal model 4JVI with the docked molecule <b>Ie</b>. The protein structure 6B8A is shown in <a href="#ddc-03-00030-f005" class="html-fig">Figure 5</a>A<sub>2</sub> in the same orientation as 4JVI in <a href="#ddc-03-00030-f005" class="html-fig">Figure 5</a>A<sub>1</sub>. The protein appears as a pink cartoon representation. A relevant water molecule is depicted as a cyan sphere. <b>Ie</b>, <b>QSI-2</b> and <b>M64</b> are in stick representations. Nitrogen, oxygen and chlorine atoms are coloured in blue, red and green, respectively. The location of the main residues involved in the interactions with ligands are depicted in black. Dark red, light green and light blue dashed lines indicate hydrogen bonds, halogens and π-stacking interactions, respectively. (<b>B</b>). Schemes generated in accordance with Ligplot schematic diagrams present the significant interactions between the residues lining the autoinduction site of PqsR and (<b>B<sub>1</sub></b>) <b>QSI-2</b>, (<b>B<sub>2</sub></b>) <b>Ie</b> or (<b>B<sub>3</sub></b>) <b>M64</b> [<a href="#B44-ddc-03-00030" class="html-bibr">44</a>,<a href="#B45-ddc-03-00030" class="html-bibr">45</a>]. Residues shown in light blue are involved in hydrophobic interactions that are considered relevant within a distance of 3.90 Å. π-stacking interactions are depicted as light blue dashed lines associated with spheres. Hydrogen and halogen interactions with distances from 2.86 to 3.98 are represented by dark red and light green dashed lines connected with the corresponding residues, respectively.</p>
Full article ">Scheme 1
<p>Reagents and conditions: (<b>i</b>) Zn(CN)<sub>2</sub> (0.75 eq), Pd(PPh<sub>3</sub>)<sub>4</sub> (0.05 eq), DMF, reflux, 1 h (under Ar); (<b>ii</b>) <span class="html-italic">m</span>-CPBA (1.8 eq), CH<sub>2</sub>Cl<sub>2</sub>, r.t., 4 h; (<b>iii</b>) POBr<sub>3</sub> (1.2 eq), DMF (0.5 eq), CH<sub>2</sub>Cl<sub>2</sub>, r.t., 1–4 h (under Ar).</p>
Full article ">Scheme 2
<p>Reagents and conditions: (<b>i</b>) DHP (1.5 eq), APTS (0.05 eq), THF, reflux, overnight; (<b>ii</b>) Bis(pinacolato)diboron (1.1 eq), KOAc (2.5 eq), PdCl<sub>2</sub>(dppf).CH<sub>2</sub>Cl<sub>2</sub> (0.08 eq), 1,4-dioxane, reflux, 1–19 h (under Ar); (<b>iii</b>) 4′-, 5′- or 6′-indazolylboronic acid pinacol ester <b>5a-c</b> (1.1 eq), Pd(PPh<sub>3</sub>)<sub>4</sub> (0.05 eq), Cs<sub>2</sub>CO<sub>3</sub> (2 eq), 1,4-dioxane, reflux, 19–44 h (under Ar); (<b>iv</b>) AcOH/H<sub>2</sub>O 4:1, reflux, 18–47 h; (<b>v</b>) 1-Cbz-piperazine (1.2 eq), Pd(OAc)<sub>2</sub> (0.1 eq), BINAP (0.12 eq), Cs<sub>2</sub>CO<sub>3</sub> (2.8 eq), 1,4-dioxane, reflux, 27 h (under Ar); (<b>vi</b>) H<sub>2</sub>, Pd/C (10% <span class="html-italic">w</span>/<span class="html-italic">w</span>), MeOH, r.t., 14 h; (<b>vii</b>) 5-(piperazin-1-yl)-1-THP-indazole <b>7</b> (1.2 eq), Pd(OAc)<sub>2</sub> (0.1 eq), XantPhos (0.12 eq), Cs<sub>2</sub>CO<sub>3</sub> (2.8 eq), 1,4-dioxane, reflux, 28 h (under Ar).</p>
Full article ">
25 pages, 6202 KiB  
Article
Identification of Novel Isatin Derivative Bearing a Nitrofuran Moiety as Potent Multi-Isoform Aldehyde Dehydrogenase Inhibitor
by Krishne Gowda, Asif Raza, Venugopal Vangala, Nazir Ahmad Lone, Jyh Ming Lin, Jaikee Kumar Singh, Sandeep Kumar Srivastava, Todd D. Schell, Gavin P. Robertson, Shantu Amin and Arun K. Sharma
Molecules 2024, 29(13), 3114; https://doi.org/10.3390/molecules29133114 - 29 Jun 2024
Viewed by 1408
Abstract
Aldehyde dehydrogenases (ALDHs) are a family of enzymes that aid in detoxification and are overexpressed in several different malignancies. There is a correlation between increased expression of ALDH and a poor prognosis, stemness, and resistance to several drugs. Several ALDH inhibitors have been [...] Read more.
Aldehyde dehydrogenases (ALDHs) are a family of enzymes that aid in detoxification and are overexpressed in several different malignancies. There is a correlation between increased expression of ALDH and a poor prognosis, stemness, and resistance to several drugs. Several ALDH inhibitors have been generated due to the crucial role that ALDH plays in cancer stem cells. All of these inhibitors, however, are either ineffective, very toxic, or have yet to be subjected to rigorous testing on their effectiveness. Although various drug-like compounds targeting ALDH have been reported in the literature, none have made it to routine use in the oncology clinic. As a result, new potent, non-toxic, bioavailable, and therapeutically effective ALDH inhibitors are still needed. In this study, we designed and synthesized potent multi-ALDH isoform inhibitors based on the isatin and indazole pharmacophore. Molecular docking studies and enzymatic tests revealed that among all of the synthesized analogs, compound 3 is the most potent inhibitor of ALDH1A1, ALDH3A1, and ALDH1A3, exhibiting 51.32%, 51.87%, and 36.65% inhibition, respectively. The ALDEFLUOR assay further revealed that compound 3 acts as an ALDH broad spectrum inhibitor at 500 nM. Compound 3 was also the most cytotoxic to cancer cells, with an IC50 in the range of 2.1 to 3.8 µM for ovarian, colon, and pancreatic cancer cells, compared to normal and embryonic kidney cells (IC50 7.1 to 8.7 µM). Mechanistically, compound 3 increased ROS activity due to potent multi-ALDH isoform inhibition, which increased apoptosis. Taken together, this study identified a potent multi-isoform ALDH inhibitor that could be further developed as a cancer therapeutic. Full article
(This article belongs to the Section Medicinal Chemistry)
Show Figures

Graphical abstract

Graphical abstract
Full article ">Figure 1
<p>Specific and multi-isoform ALDH inhibitors.</p>
Full article ">Figure 2
<p>Molecular docking 3D representation of compound <b>3</b> in the active site pockets of (<b>A</b>) ALDH1A1 (PDB ID: 4 × 4 L) (<b>B</b>) ALDH1A3 (PDB ID: 7QK7) (<b>C</b>) ALDH3A1 (PDB ID: 3SZB).</p>
Full article ">Figure 3
<p>Inhibition of ALDH Activity in Human Melanoma by Compound <b>3</b> and KS100. ALDEFLUOR assay using DEAB as a negative control. UACC 903 cells treated with Compound <b>3</b> and KS100 were stained with ALDEFLUOR dye (<b>A</b>), and the resulting bar graph represents triplicates (<b>B</b>). Both compounds exhibited significant inhibition of ALDH activity, suggesting their potential therapeutic relevance in human melanoma. The bar graph displays the mean ± SD of three replicates. Statistical analysis was conducted using one-way ANOVA with GraphPad PRISM Version 6 software, followed by Tukey’s multiple comparisons test. Statistical significance was established at a <span class="html-italic">p</span>-value of &lt; 0.05.</p>
Full article ">Figure 4
<p>(<b>A</b>) HCT-116, SKOV-3, MIA PaCa-2, HEK-293, and FHC cell lines were treated with compound <b>3</b> (<b>KS124</b>) and <b>KS100</b> for 48 h at different concentrations. At the end of the treatment duration, an MTS assay was performed. The data were analyzed on GraphPad V 8.0 software (Prism, CA, USA) using non-linear regression. (<b>B</b>) Trypan blue dye exclusion assay–HCT-116 cells were treated with 3 µM of compounds 3 (<b>KS124</b>) and <b>KS100</b> for 48 h. The cells were harvested and stained with trypan blue. The live cells (excluded trypan blue) and dead cells (stained with trypan blue) were counted using a hemocytometer. Data are presented as mean ± SD; <span class="html-italic">n</span> = 3 for each treatment with * <span class="html-italic">p</span> &lt; 0.05.</p>
Full article ">Figure 5
<p>(<b>A</b>) HCT-116 cells were treated with compound <b>3</b> (<b>KS124</b>) and <b>KS100</b> 24 h (Caspase 3/7 assay) and 48 h (Annexin V/7-AAD assay). (<b>B</b>,<b>C</b>) represent the quantification of the apoptotic cell population after the Caspase 3/7 assay and Annexin V/7-AAD assay, respectively. Data are presented as Mean ± SEM; <span class="html-italic">n</span> = 3 for each treatment.</p>
Full article ">Figure 6
<p>(<b>A</b>) The generation of ROS in HCT-116 cells was assessed by using the Muse oxidative stress kit. Untreated HCT-116 cells were taken as the control, and cells were treated in the presence or absence of the antioxidant NAC (10 mM). HCT-116 cells were treated with 3 µM of compound <b>3</b> (<b>KS124</b>) and KS100 for 24 h. Data are presented as mean ± SD; <span class="html-italic">n</span> = 3 for each treatment at each time point. * <span class="html-italic">p</span> &lt; 0.05 compared to <b>KS100</b> treated cells. (<b>B</b>) Western blot demonstrating increased γH2AX protein levels in HCT-116 cell lines treated with 3 µM of compound <b>3</b> and <b>KS100</b> for 12 h.</p>
Full article ">Scheme 1
<p>Synthesis of novel isatin derivatives (<b>1</b>–<b>7</b>). Reagents and conditions: a) K<sub>2</sub>CO<sub>3</sub>, DMF, 4-(bromomethyl)benzaldehyde, RT; b) K<sub>2</sub>CO<sub>3</sub>, DMF, methyl (2E)-3-[4-(bromomethyl)phenyl]-2 propenoate, RT; c) K<sub>2</sub>CO<sub>3</sub>, DMF, 1,4-bis(bromomethyl)benzene, RT; d) <span class="html-italic">N</span>-allylthiourea, EtOH, reflux; e) Cs<sub>2</sub>CO<sub>3</sub>, DMF, 5-nitro-2-furoic acid, RT; f) Cs<sub>2</sub>CO<sub>3</sub>, DMF, 2-furoic acid, RT; g) thiourea, EtOH, reflux.</p>
Full article ">Scheme 2
<p>Synthesis of novel indazole derivatives (<b>8</b>–<b>21</b>). Reagents and conditions: (a) NaH, DMF, 60 °C, methyl (2E)-3-[4-(bromomethyl)phenyl]-2-propenoate; (b) NaH, DMF, 60 °C, 1,4-bis(bromomethyl)benzene, RT; (c) NaH, DMF, 60 °C, 4-(bromomethyl)benzyl)oxy)TBDMS; (d) THF, TBAF, RT; (e) NaH, DMF, 60 °C, 4-(bromomethyl)benzaldehyde; (f) NaH, DMF, 60 °C,1-(4 (Bromomethyl)phenyl)ethanone; (g) <span class="html-italic">N</span>-allylthiourea, EtOH, reflux; (h) thiourea, EtOH, reflux; (i) Paraformaldehyde, dimethyl amine, EtOH, RT.</p>
Full article ">
10 pages, 2042 KiB  
Article
Practical Synthesis of 7-Bromo-4-chloro-1H-indazol-3-amine: An Important Intermediate to Lenacapavir
by Naeem Asad, Michael Lyons, Shirley Muniz Machado Rodrigues, Justina M. Burns, Thomas D. Roper, G. Michael Laidlaw, Saeed Ahmad, B. Frank Gupton, Douglas Klumpp and Limei Jin
Molecules 2024, 29(12), 2705; https://doi.org/10.3390/molecules29122705 - 7 Jun 2024
Viewed by 1242
Abstract
7-Bromo-4-chloro-1H-indazol-3-amine is a heterocyclic fragment used in the synthesis of Lenacapavir, a potent capsid inhibitor for the treatment of HIV-1 infections. In this manuscript, we describe a new approach to synthesizing 7-bromo-4-chloro-1H-indazol-3-amine from inexpensive 2,6-dichlorobenzonitrile. This synthetic method utilizes [...] Read more.
7-Bromo-4-chloro-1H-indazol-3-amine is a heterocyclic fragment used in the synthesis of Lenacapavir, a potent capsid inhibitor for the treatment of HIV-1 infections. In this manuscript, we describe a new approach to synthesizing 7-bromo-4-chloro-1H-indazol-3-amine from inexpensive 2,6-dichlorobenzonitrile. This synthetic method utilizes a two-step sequence including regioselective bromination and heterocycle formation with hydrazine to give the desired product in an overall isolated yield of 38–45%. The new protocol has been successfully demonstrated on hundred-gram scales without the need for column chromatography purification. This new synthesis provides a potential economical route to the large-scale production of this heterocyclic fragment of Lenacapavir. Full article
Show Figures

Figure 1

Figure 1
<p>Biologically active 3-aminoindazoles.</p>
Full article ">Scheme 1
<p>Initial attempt at synthesis of <b>6</b>.</p>
Full article ">Scheme 2
<p>Synthesis of indazole <b>6</b> through regioselective cyclization of <b>8</b>.</p>
Full article ">Scheme 3
<p>A plausible pathway for the formation of indazoles.</p>
Full article ">
14 pages, 2026 KiB  
Article
Mucolytic Drugs Ambroxol and Bromhexine: Transformation under Aqueous Chlorination Conditions
by Sergey A. Sypalov, Ilya S. Varsegov, Nikolay V. Ulyanovskii, Albert T. Lebedev and Dmitry S. Kosyakov
Int. J. Mol. Sci. 2024, 25(10), 5214; https://doi.org/10.3390/ijms25105214 - 10 May 2024
Cited by 1 | Viewed by 999
Abstract
Bromhexine and ambroxol are among the mucolytic drugs most widely used to treat acute and chronic respiratory diseases. Entering the municipal wastewater and undergoing transformations during disinfection with active chlorine, these compounds can produce nitrogen- and bromine-containing disinfection by-products (DBPs) that are dangerous [...] Read more.
Bromhexine and ambroxol are among the mucolytic drugs most widely used to treat acute and chronic respiratory diseases. Entering the municipal wastewater and undergoing transformations during disinfection with active chlorine, these compounds can produce nitrogen- and bromine-containing disinfection by-products (DBPs) that are dangerous for aquatic ecosystems. In the present study, primary and deep degradation products of ambroxol and bromhexine obtained in model aquatic chlorination experiments were studied via the combination of high-performance liquid and gas chromatography with high-resolution mass spectrometry. It was shown that at the initial stages, the reactions of cyclization, hydroxylation, chlorination, electrophilic ipso-substitution of bromine atoms with chlorine, and oxidative N-dealkylation occur. Along with known metabolites, a number of novel primary DBPs were tentatively identified based on their elemental compositions and tandem mass spectra. Deep degradation of bromhexine and ambroxol gives twenty-four identified volatile and semi-volatile compounds of six classes, among which trihalomethanes account for more than 50%. The specific class of bromhexine- and ambroxol-related DBPs are bromine-containing haloanilines. Seven of them, including methoxy derivatives, were first discovered in the present study. One more novel class of DBPs associated with bromhexine and ambroxol is represented by halogenated indazoles formed through dealkylation of the primary transformation products containing pyrazoline or tetrahydropyrimidine cycle in their structure. Full article
(This article belongs to the Section Molecular Pharmacology)
Show Figures

Figure 1

Figure 1
<p>The structural formulas of ambroxol (<b>a</b>) and bromhexine (<b>b</b>).</p>
Full article ">Figure 2
<p>Bromhexine degradation pathways and primary transformation products formed during the aqueous chlorination.</p>
Full article ">Figure 3
<p>Scheme of the formation of detected DBPs during the interaction of ambroxol with active chlorine.</p>
Full article ">Figure 4
<p>Chromatographic peak areas of parent compounds and primary transformation products of bromhexine (<b>a</b>,<b>b</b>) and ambroxol (<b>c</b>,<b>d</b>) at active chlorine concentrations of 4 (<b>a</b>,<b>c</b>) and 7 (<b>b</b>,<b>d</b>) mg L<sup>−1</sup> depending on the reaction time.</p>
Full article ">
16 pages, 3041 KiB  
Article
Timeframe Analysis of Novel Synthetic Cannabinoids Effects: A Study on Behavioral Response and Endogenous Cannabinoids Disruption
by Jorge Carlos Pineda Garcia, Ren-Shi Li, Ruri Kikura-Hanajiri, Yoshitaka Tanaka and Yuji Ishii
Int. J. Mol. Sci. 2024, 25(6), 3083; https://doi.org/10.3390/ijms25063083 - 7 Mar 2024
Viewed by 1161
Abstract
This study investigates the impact of SCs consumption by assessing the effects of three novel synthetic cannabinoids (SCs); MDMB-CHMINACA, 5F-ADB-PINACA, and APICA post-drug treatment. SCs are known for their rapid onset (<1 min) and prolonged duration (≥5 h). Therefore, this research aimed to [...] Read more.
This study investigates the impact of SCs consumption by assessing the effects of three novel synthetic cannabinoids (SCs); MDMB-CHMINACA, 5F-ADB-PINACA, and APICA post-drug treatment. SCs are known for their rapid onset (<1 min) and prolonged duration (≥5 h). Therefore, this research aimed to assess behavioral responses and their correlation with endocannabinoids (ECs) accumulation in the hippocampus, and EC’s metabolic enzymes alteration at different timeframes (1-3-5-h) following drug administration. Different extents of locomotive disruption and sustained anxiety-like symptoms were observed throughout all-encompassing timeframes of drug administration. Notably, MDMB-CHMINACA induced significant memory impairment at 1 and 3 h. Elevated levels of anandamide (AEA) and 2-arachidonoyl glycerol (2-AG) were detected 1 h post-MDMB-CHMINACA and 5F-ADB-PINACA administration. Reduced mRNA expression levels of fatty acid amide hydrolase (FAAH), monoacylglycerol lipase (MAGL) (AEA and 2-AG degrading enzymes, respectively), and brain-derived neurotrophic factor (BDNF) occurred at 1 h, with FAAH levels remaining reduced at 3 h. These findings suggest a connection between increased EC content and decreased BDNF expression following SC exposure. Cognitive disruption, particularly motor coordination decline and progressive loss manifested in a time-dependent manner across all the analyzed SCs. Our study highlights the importance of adopting a temporal framework when assessing the effects of SCs. Full article
(This article belongs to the Special Issue New Insight into Cannabinoid Effects 3.0)
Show Figures

Figure 1

Figure 1
<p>Schematic representation of the chemical structures and substituents of indole/indazole derivatives synthetic cannabinoids; MDMB-CHMINACA, 5F-ADB-PINACA, APICA. The ease of insertion of an additional N atom into the heterocyclic system of the classic synthetic cannabinoid JWH-018 and the archetypal aminoalkylindole-based synthetic cannabinoid MDMB-CHMICA structures along with the presence of a carboxamide group, diverse substituents on both the N-1 atom of the indazole ring, and the carboxamide N atom promote the synthesis of many indazole-3-carboxamide based SCs. They usually comprise an indazole-carboxamides or N-1-adamantyl indole-carboxamide at the 3-position. Adapted from [<a href="#B29-ijms-25-03083" class="html-bibr">29</a>].</p>
Full article ">Figure 2
<p>Schematic diagram of behavioral studies. (<b>A</b>) Outline of the exploration trial and anxiety assessment configuration. (<b>B</b>) Layout of the recognition trial arena tests. Adapted from [<a href="#B39-ijms-25-03083" class="html-bibr">39</a>].</p>
Full article ">Figure 3
<p>Effects of 1 mg/kg systemic administration of MDMB-CHMINACA, APICA, and 5F-ADB-PINACA on the (<b>A</b>) total distance traveled (cm) and (<b>B</b>) velocity (cm/s) during the open field test in mice. Drugs were administered 1 h, 3 h, and 5 h prior to the test. All drug-treated groups were compared with the respective vehicle-treated group (control). Each bar represents the mean ± SEM of 10 mice for each treatment. Statistical analysis was performed by two-way ANOVA followed by Tukey’s post hoc for multiple comparison among data set. * <span class="html-italic">p</span> &lt; 0.05, ** <span class="html-italic">p</span> &lt; 0.01, and *** <span class="html-italic">p</span> &lt; 0.001, indicate a significant difference compared to controls, and + <span class="html-italic">p</span> &lt; 0.05, and +++ <span class="html-italic">p</span> &lt; 0.001 versus 1 h vehicle treated group.</p>
Full article ">Figure 4
<p>Effect of 1 mg/kg systemic administration of MDMB-CHMINACA, APICA, and 5F-ADB-PINACA on the anxiety-like behavior of mice. Anxiety-like behavior was measured as the amount of time (s) mice spent in the INNER area vs. the OUTER area of the arena during the OFT. Longer periods in the OUTER area reflect anxiety-like behavior. All drug-treated groups’ INNER fragments were compared to the INNER fragment of the vehicle-treated groups (control). Each bar represents the mean ± SEM of 10 mice for each treatment. Statistical analysis was performed by two-way ANOVA followed by Bonferroni’s post hoc for multiple comparison among data set * <span class="html-italic">p</span> &lt; 0.05, ** <span class="html-italic">p</span> &lt; 0.01, and *** <span class="html-italic">p</span> &lt; 0.001, indicate significant differences compared to control. ns, not significant.</p>
Full article ">Figure 5
<p>Effects of 1 mg/kg systemic administration of MDMB-CHMINACA, APICA, and 5F-ADB-PINACA on the recognition index for the novel object recognition test in mice. Trial is based on the index (%) of exploration and consequent preferences of mice toward a novel object compared to a previously familiarized object. Values closer to one indicate no memory and learning impairment and values below 0.5 suggest strong memory impairment. All drug treatments were administered intraperitoneally. Each bar represents the mean ± SEM of 10 mice for each treatment. Statistical analysis was performed by two-way ANOVA followed by Tukey’s post hoc for multiple comparison among data set. ** <span class="html-italic">p</span> &lt; 0.01 and *** <span class="html-italic">p</span> &lt; 0.001 indicate significant differences compared to control (vehicle).</p>
Full article ">Figure 6
<p>Effect of MDMB-CHMINACA, APICA, and 5F-ADB-PINACA on the mRNA expression levels of brain-derived neurotrophic factor (BDNF). Mice were administered 1 mg/kg of either MDMB-CHMINACA, APICA, 5F-DB-PINACA, or vehicle (control) at 1 h, 3 h, and 5 h, as shown. Their hippocampi were collected after treatment. The indicated/relative levels of mRNA were analyzed via quantitative reverse transcription real-time polymerase chain reaction (qRT-PCR) and normalized to those of β-actin. The bars represent the mean ± SEM of 5 mice. Statistical analysis was performed by two-way ANOVA followed by Tukey’s post hoc for multiple comparison among data set. ** <span class="html-italic">p</span> &lt; 0.01 indicates significant difference compared to control.</p>
Full article ">Figure 7
<p>Quantification of the endogenous cannabinoids (<b>A</b>) AEA and (<b>B</b>) 2-AG content in hippocampal tissue of male C57BL/6J mice 1, 3, and 5 h after synthetic cannabinoid treatment. Each mouse was administered a 1 mg/kg dose of MDMB-CHMINACA, APICA, 5F-ADB-PINACA, or vehicle (control) as shown. Subsequently, endocannabinoid content was quantified via UPLC-TOF/MS. Each drug treatment was compared to its control (vehicle). Each bar represents the mean ± SEM of 5 mice for each treatment. Statistical analysis was performed by two-way ANOVA followed by Tukey’s post hoc for multiple comparison among data set. * <span class="html-italic">p</span> &lt; 0.05, ** <span class="html-italic">p</span> &lt; 0.01, and *** <span class="html-italic">p</span> &lt; 0.001, indicate significant differences compared to control.</p>
Full article ">Figure 8
<p>Effect of MDMB-CHMINACA, APICA, and 5F-ADB-PINACA on the mRNA expression of (<b>A</b>) AEA-degrading enzyme (FAAH) and (<b>B</b>) 2-AG degrading enzyme (MAGL). Mice were administered 1 mg/kg of MDMB-CHMINACA, APICA, 5F-DB-PINACA, or vehicle (control) at 1, 3, and 5 h, as shown. Their hippocampi were collected after treatment. The indicated/relative levels of mRNA were analyzed via quantitative reverse transcription real-time polymerase chain reaction (qRT-PCR) and normalized to those of β-actin. The bars represent the mean ± SEM of 5 mice. Statistical analysis was performed by two-way ANOVA followed by Tukey’s post hoc for multiple comparison among data set. * <span class="html-italic">p</span> &lt; 0.05 and ** <span class="html-italic">p</span> &lt; 0.01, indicate significant differences compared to control.</p>
Full article ">
17 pages, 3139 KiB  
Article
Air- and Water-Stable Heteroleptic Copper (I) Complexes Bearing Bis(indazol-1-yl)methane Ligands: Synthesis, Characterisation, and Computational Studies
by David Moreno-da Costa, César Zúñiga-Loyola, Federico Droghetti, Stephania Robles, Alondra Villegas-Menares, Nery Villegas-Escobar, Ivan Gonzalez-Pavez, Elies Molins, Mirco Natali and Alan R. Cabrera
Molecules 2024, 29(1), 47; https://doi.org/10.3390/molecules29010047 - 20 Dec 2023
Viewed by 1276
Abstract
A series of four novel heteroleptic Cu(I) complexes, bearing bis(1H-indazol-1-yl)methane analogues as N,N ligands and DPEPhos as the P,P ligand, were synthesised in high yields under mild conditions and characterised by spectroscopic and spectrometric techniques. In addition, the position [...] Read more.
A series of four novel heteroleptic Cu(I) complexes, bearing bis(1H-indazol-1-yl)methane analogues as N,N ligands and DPEPhos as the P,P ligand, were synthesised in high yields under mild conditions and characterised by spectroscopic and spectrometric techniques. In addition, the position of the carboxymethyl substituent in the complexes and its effect on the electrochemical and photophysical behaviour was evaluated. As expected, the homoleptic copper (I) complexes with the N,N ligands showed air instability. In contrast, the obtained heteroleptic complexes were air- and water-stable in solid and solution. All complexes displayed green-yellow luminescence in CH2Cl2 at room temperature due to ligand-centred (LC) phosphorescence in the case of the Cu(I) complex with an unsubstituted N,N ligand and metal-to-ligand charge transfer (MLCT) phosphorescence for the carboxymethyl-substituted complexes. Interestingly, proper substitution of the bis(1H-indazol-1-yl)methane ligand enabled the achievement of a remarkable luminescent yield (2.5%) in solution, showcasing the great potential of this novel class of copper(I) complexes for potential applications in luminescent devices and/or photocatalysis. Full article
(This article belongs to the Section Photochemistry)
Show Figures

Figure 1

Figure 1
<p>Molecular structures of <b>C1</b>, <b>C3</b>, and <b>C4</b> obtained by XRD. Hydrogen atoms, solvent molecules, and counterion were omitted for clarity. Thermal ellipsoids are at 30% probability.</p>
Full article ">Figure 2
<p>Frontier molecular orbitals iso-surfaces (0.03 a.u.) for <b>C1</b>-<b>4</b>, orbital contributions for the metal centre (Cu), and <span class="html-italic">N,N</span> and <span class="html-italic">P,P</span> ligands are also shown. The energy gap is reported in eV.</p>
Full article ">Figure 3
<p>Absorption spectra of <b>C1-4</b> in CH<sub>2</sub>Cl<sub>2</sub>.</p>
Full article ">Figure 4
<p>Normalised absorption spectra of complexes <b>C1-4</b> in CH<sub>2</sub>Cl<sub>2</sub>. Vertical electronic transitions and oscillator strengths (<span class="html-italic">f</span>, in a.u.) computed at the B3LYP-D3/6-31G(d,p)-LANL2DZ(Cu) are also shown.</p>
Full article ">Figure 5
<p>Hole–electron distributions, in yellow and blue, respectively, of the first excited state for systems <b>C1</b>-<b>4</b> (isovalue 0.0015 a.u.).</p>
Full article ">Figure 6
<p>Luminescence spectra of complexes <b>C1-4</b> in N<sub>2</sub>-purged CH<sub>2</sub>Cl<sub>2</sub> and in a rigid matrix (2-MeTHF) at 77 K: (<b>a</b>) <b>C1</b> (excitation at 320 nm at RT, 330 nm at 77 K), (<b>b</b>) <b>C2</b> (excitation at 410 nm at RT, 360 nm at 77 K), (<b>c</b>) <b>C3</b> (excitation at 355 nm at RT, 350 nm at 77 K), and (<b>d</b>) <b>C4</b> (excitation at 355 nm at RT, 350 nm at 77 K).</p>
Full article ">Figure 7
<p>(<b>a</b>) Emission map of complex <b>C3</b> in CH<sub>2</sub>Cl<sub>2</sub> and (<b>b</b>) relevant emission spectra.</p>
Full article ">Scheme 1
<p>Synthetic route to obtaining bis(1<span class="html-italic">H</span>-indazol-1-yl)methane ligands <b>L1-4</b>.</p>
Full article ">Scheme 2
<p>Synthetic route to obtaining Cu(I) complexes <b>C1-4</b>.</p>
Full article ">
20 pages, 2205 KiB  
Article
Synthesis of Trifluoromethylated Pyrimido[1,2-b]indazole Derivatives through the Cyclocondensation of 3-Aminoindazoles with Ketoester and Their Functionalization via Suzuki-Miyaura Cross-Coupling and SNAr Reactions
by Sakina Tellal, Badr Jismy, Djamila Hikem-Oukacha and Mohamed Abarbri
Molecules 2024, 29(1), 44; https://doi.org/10.3390/molecules29010044 - 20 Dec 2023
Viewed by 1013
Abstract
A new series of trifluoromethylated pyrimido[1,2-b]indazol-4(1H)-one derivatives was synthesized with good to excellent yields through a simple condensation of 3-aminoindazole derivatives with ethyl 4,4,4-trifluoro 3-oxobutanoate. The functionalization of the corresponding chlorinated fused tricyclic scaffolds via Suzuki-Miyaura and aromatic nucleophilic [...] Read more.
A new series of trifluoromethylated pyrimido[1,2-b]indazol-4(1H)-one derivatives was synthesized with good to excellent yields through a simple condensation of 3-aminoindazole derivatives with ethyl 4,4,4-trifluoro 3-oxobutanoate. The functionalization of the corresponding chlorinated fused tricyclic scaffolds via Suzuki-Miyaura and aromatic nucleophilic substitution reactions led to the synthesis of highly diverse trifluoromethylated pyrimido[1,2-b]indazole derivatives with good yields. Full article
Show Figures

Graphical abstract

Graphical abstract
Full article ">Figure 1
<p>Some representatively bioactive pyrimido[1,2-<span class="html-italic">b</span>]indazole derivatives.</p>
Full article ">Figure 2
<p>Convergent approach for the synthesis of fluorinated pyrimido[1,2-<span class="html-italic">b</span>]indazole derivatives [<a href="#B9-molecules-29-00044" class="html-bibr">9</a>,<a href="#B25-molecules-29-00044" class="html-bibr">25</a>,<a href="#B26-molecules-29-00044" class="html-bibr">26</a>].</p>
Full article ">Scheme 1
<p>Scope of 3-aminoindazole derivatives.</p>
Full article ">Scheme 2
<p>Synthesis of trifluoromethylated 4-chloro-2-(trifluoromethyl)pyrimido[1,2-<span class="html-italic">b</span>]indazole derivatives <b>3a–h</b>.</p>
Full article ">Scheme 3
<p>Behavior of 4-chloro-2-(trifluoromethyl)pyrimido[1,2-<span class="html-italic">b</span>]indazole derivatives <b>3a–h</b> in the Suzuki–Miyaura cross coupling.</p>
Full article ">Scheme 4
<p>Scope of the Suzuki–Miyaura cross-coupling.</p>
Full article ">Scheme 5
<p>Synthesis route of 4-amino-2-trifluoromethyl pyrimido[1,2-<span class="html-italic">b</span>]indazole derivatives <b>6a–g</b>.</p>
Full article ">Scheme 6
<p>Synthesis route of 4-(alkylthio or arylthiol)-2-(trifluoromethyl)pyrido[2′,3′:3,4]pyrazolo[1,5-<span class="html-italic">a</span>]pyrimidine <b>7a–c</b>.</p>
Full article ">Scheme 7
<p>Synthesis of 7-alkoxy (or 7-phenoxy)-2-trifluoromethyl pyrimido[1,2-<span class="html-italic">b</span>]indazole derivatives <b>7a–c</b>.</p>
Full article ">
24 pages, 9582 KiB  
Review
Monofluoromethylation of N-Heterocyclic Compounds
by Mikhail Yu. Moskalik
Int. J. Mol. Sci. 2023, 24(24), 17593; https://doi.org/10.3390/ijms242417593 - 18 Dec 2023
Viewed by 1594
Abstract
The review focuses on recent advances in the methodologies for the formation or introduction of the CH2F moiety in N-heterocyclic substrates over the past 5 years. The monofluoromethyl group is one of the most versatile fluorinated groups used to modify [...] Read more.
The review focuses on recent advances in the methodologies for the formation or introduction of the CH2F moiety in N-heterocyclic substrates over the past 5 years. The monofluoromethyl group is one of the most versatile fluorinated groups used to modify the properties of molecules in synthetic medical chemistry. The review summarizes two strategies for the monofluoromethylation of N-containing heterocycles: direct monofluoromethylation with simple XCH2F sources (for example, ICH2F) and the assembly of N-heterocyclic structures from CH2F-containing substrates. The review describes the monofluoromethylation of pharmaceutically important three-, five- and six-membered N-heterocycles: pyrrolidines, pyrroles, indoles, imidazoles, triazoles, benzothiazoles, carbazoles, indazoles, pyrazoles, oxazoles, piperidines, morpholines, pyridines, quinolines and pyridazines. Assembling of 6-fluoromethylphenanthridine, 5-fluoromethyl-2-oxazolines, C5-monofluorinated isoxazoline N-oxides, and α-fluoromethyl-α-trifluoromethylaziridines is also shown. Fluoriodo-, fluorchloro- and fluorbromomethane, FCH2SO2Cl, monofluoromethyl(aryl)sulfoniummethylides, monofluoromethyl sulfides, (fluoromethyl)triphenylphosphonium iodide and 2-fluoroacetic acid are the main fluoromethylating reagents in recent works. The replacement of atoms and entire functional groups with a fluorine atom(s) leads to a change and often improvement in activity, chemical or biostability, and pharmacokinetic properties. The monofluoromethyl group is a bioisoster of -CH3, -CH2OH, -CH2NH2, -CH2CH3, -CH2NO2 and -CH2SH moieties. Bioisosteric replacement with the CH2F group is both an interesting task for organic synthesis and a pathway to modify drugs, agrochemicals and useful intermediates. Full article
(This article belongs to the Section Physical Chemistry and Chemical Physics)
Show Figures

Scheme 1

Scheme 1
<p>The synthesis of α-fluoromethyl-α-trifluoromethylaziridines <b>4</b> via the reaction of trifluoroactimidoyl chloride (TFAIC) <b>1</b> and lithium monohalocarbenoids.</p>
Full article ">Scheme 2
<p>Synthesis of α-fluoroaziridine from <span class="html-italic">N</span>-tosyl-substituted diphenyl ketimine and ICH<sub>2</sub>F.</p>
Full article ">Scheme 3
<p>Hydrofluoromethylation of <span class="html-italic">N</span>-Benzylmaleimide using ICH<sub>2</sub>F and (TMS)<sub>3</sub>SiH.</p>
Full article ">Scheme 4
<p>Formation of 3-fluoromethylated <span class="html-italic">N</span>-benzylpyrrolidine.</p>
Full article ">Scheme 5
<p>Hydrofluoromethylation of pyrrolidines in the presence of 2-phenylacetaldehyde.</p>
Full article ">Scheme 6
<p>Synthesis of 3-fluoromethylated indolines with nucleophilic ring-opening of oxirane ring in spiro-epoxyoxindoles.</p>
Full article ">Scheme 7
<p><span class="html-italic">N</span>-Methyl-<span class="html-italic">N</span>-phenylmethacrylamide cyclization using CH<sub>2</sub>FSO<sub>2</sub>Cl.</p>
Full article ">Scheme 8
<p>The proposed mechanism for <span class="html-italic">N</span>-Methyl-<span class="html-italic">N</span>-phenylmethacrylamide cyclization in the presence of CH<sub>2</sub>FSO<sub>2</sub>Cl.</p>
Full article ">Scheme 9
<p><span class="html-italic">N</span>-Fluoromethoxymethylation of aromatic heterocycles using ICH<sub>2</sub>F in the presence of KOH.</p>
Full article ">Scheme 10
<p>The proposed mechanism of <span class="html-italic">N</span>-fluoromethoxymethylation of aromatic heterocycles using ICH<sub>2</sub>F in the presence of KOH.</p>
Full article ">Scheme 11
<p><span class="html-italic">N</span>-Fluoromethylation of <span class="html-italic">N</span>-heterocycles using ICH<sub>2</sub>F in the presence of Cs<sub>2</sub>CO<sub>3.</sub></p>
Full article ">Scheme 12
<p>Electrophilic <span class="html-italic">N</span>-Fluoromethylation of heteroarenes using monofluoromethyl(aryl)sulfonium bis(carbomethoxy)methylide.</p>
Full article ">Scheme 13
<p>Synthesis of monofluoromethyl(aryl)sulfonium bis(carbomethoxy)methylide.</p>
Full article ">Scheme 14
<p>Bisfluoromethylation of 2-methylimidazolole.</p>
Full article ">Scheme 15
<p><span class="html-italic">O</span>-Fluoromethylation of <span class="html-italic">N</span>-substituted 5-hydroxypyrazoles <b>24</b> using ICH<sub>2</sub>F in the presence of Cs<sub>2</sub>CO<sub>3</sub>.</p>
Full article ">Scheme 16
<p><b><span class="html-italic">S</span></b>-Fluoromethylation of 2-thio-benzo[d]oxazole and 2-thio-benzo[d]thiazole using ICH<sub>2</sub>F in the presence of Cs<sub>2</sub>CO<sub>3</sub>.</p>
Full article ">Scheme 17
<p>Synthesis of monofluoromethyl selenoethers using 2-(amimo)benzooxazole and 2-(amimo)benzothiazole.</p>
Full article ">Scheme 18
<p>The proposed mechanism for the selenomonofluoromethylation of 2-(amimo)benzooxazole and 2-(amimo)benzothiazole.</p>
Full article ">Scheme 19
<p>Synthesis of azidofluoromethane and 4-substituted 1,2,3-triazoles.</p>
Full article ">Scheme 20
<p>4,5-Disubstituted triazole formation through the reaction of azidofluoromethane using β-ketoesters or 1,3-diones.</p>
Full article ">Scheme 21
<p>Electrochemical synthesis of 5-fluoromethyl-2-oxazolines.</p>
Full article ">Scheme 22
<p>The proposed mechanism for the electrochemical synthesis of 5-fluoromethyl-2-oxazolines.</p>
Full article ">Scheme 23
<p>Synthesis of C5-monofluorinated isoxazoline N-oxides.</p>
Full article ">Scheme 24
<p>[3 + 2]-Dipolar cycloaddition of isoxazoline-N-oxides with phenylacrylate.</p>
Full article ">Scheme 25
<p><span class="html-italic">N</span>-Monofluoromethylation of saturated <span class="html-italic">N</span>-containing heterocycles using aldehydes and fluoroiodomethane.</p>
Full article ">Scheme 26
<p>4-Monofluoromethylation of 1-benzylpiperidin-4-one with lithium fluorocarbenoid.</p>
Full article ">Scheme 27
<p>The synthesis of (fluoromethyl)triphenylphosphonium iodide.</p>
Full article ">Scheme 28
<p>2-Fluoromethylation of pyridine-<span class="html-italic">N</span>-oxides.</p>
Full article ">Scheme 29
<p>The proposed mechanism for the 2-fluoromethylation of pyridine-<span class="html-italic">N</span>-oxides.</p>
Full article ">Scheme 30
<p><span class="html-italic">N</span>-Fluoromethylation of 4(1<span class="html-italic">H</span>)-cinnolinone with ICH<sub>2</sub>F in the presence of Cs<sub>2</sub>CO<sub>3.</sub></p>
Full article ">Scheme 31
<p>Synthesis of <span class="html-italic">ortho</span>-fluoromethylated pyridines in the presence of arylboronates.</p>
Full article ">Scheme 32
<p>NiI<sub>2</sub>-Catalyzed CH–monofluoroalkylation of pyridine and quinoline.</p>
Full article ">Scheme 33
<p>The synthesis of 6-fluoromethylphenanthridine through the reaction of 2-((fluoromethyl)sulfonyl)-6-nitrobenzothiazole with 2-isocyano(1,1′-diphenyl).</p>
Full article ">Scheme 34
<p>Proposed mechanism of the assembling of 6-fluoromethylphenanthridine.</p>
Full article ">Scheme 35
<p>C–H–monofluoromethylation of pyridines, pyrazines and quinoxaline.</p>
Full article ">Scheme 36
<p>C–H–bis(monofluoro)methylation of pyridines, pyrazines and quinoxalines.</p>
Full article ">Scheme 37
<p>Fluoromethylation of tRNA guanine N37 using FMeTeSAM.</p>
Full article ">Scheme 38
<p>Synthesis of FMeTeSAM.</p>
Full article ">Scheme 39
<p>Synthesis of monofluoromethyl selenoesters from quinoline-3-amine.</p>
Full article ">
Back to TopTop