Carboxamide Derivatives Research Articles

Design and Synthesis of Novel Diphenyl Ether Carboxamide Derivatives To Control the Phytopathogenic Fungus Sclerotinia sclerotiorum.

Sclerotinia stem rot (SSR) caused by the phytopathogenic fungus Sclerotinia sclerotiorum has led to serious losses in the yields of oilseed rape and other crops every year. Here, we designed and synthesized a series of carboxamide derivatives containing a diphenyl ether skeleton by adopting the scaffold splicing strategy. From the results of the mycelium growth inhibition experiment, inhibition rates of compounds 4j and 4i showed more than 80% to control S. sclerotiorum at a dose of 50 μg/mL, which is close to that of the positive control (flubeneteram, 95%). Then, the results of a structure-activity relationship study showed that the benzyl scaffold was very important for antifungal activity and that introducing a halogen atom on the benzyl ring would improve antifungal activity. Furthermore, the results of an in vitro activity test suggested that these novel compounds can inhibit the activity of succinate dehydrogenase (SDH), and the binding mode of 4j with SDH was basically similar to that of the flutolanil derivative. Morphological observation of mycelium revealed that compound 4j could cause a damage on the mycelial morphology and cell structure of S. sclerotiorum, resulting in inhibition of the growth of mycelia. Furthermore, in vivo antifungal activity assessment of 4j displayed a good control of S. sclerotiorum (>97%) with a result similar to that of the positive control at a concentration of 200 mg/L. Thus, the diphenyl ether carboxamide skeleton is a new starting point for the discovery of new SDH inhibitors and is worthy of further development.

Metal Catalyst-Free One-pot Synthesis of Carboxamide Derivatives via Ugi-4CC Reaction and Its Anti-tubercular Study

Background: A new series of ten composites with sulphur based carboxylic acid and benzylamine were synthesized by Ugi 4-components reaction (Ugi-4CR) and screened for antituberculosis activity against the Mycobacterium tuberculosis H37Rv strain. Objective: Target compounds were isolated, purified, identified, and characterized by MS, FT-IR, 1HNMR, APT, and 13C-NMR then the antituberculosis activity was examined by Microplate Alamar Blue Assay (MABA) method. Methods: This study was based on the articulation of carboxamide linkage bearing S-linkage in the core unit by reacting four different units, i.e., 2-(pyrimidin-2-ylthio)acetic acid, aromatic aldehyde, benzylamine and tertiary butyl isocyanide at RT in an atom economy route of synthesis. The desired product (5a- 5j) was synthesized via one-pot and Metal-free conditions. Results: Compounds (5a-5j) synthesized in good yields and compared to MIC values of Isoniazid 0.05 (μg/mL), Rifampicin 0.1 (μm/mL), and Ethambutol 1.56 (μg/mL) as a positive control. Conclusion: Synthesized compounds give excellent yield. Among the ten derivatives, compound 5f has comparable antituberculosis activity.

Design and Synthesis of Pyrazole Carboxamide Derivatives as Selective Cholinesterase and Carbonic Anhydrase Inhibitors: Molecular Docking and Biological Evaluation.

The present study focused on the synthesis and characterization of novel pyrazole carboxamide derivatives (SA1-12). The inhibitory effect of the compounds on cholinesterases (ChEs; AChE and BChE) and carbonic anhydrases (hCAs; hCA I and hCA II) isoenzymes were screened as in vitro. These series compounds have been identified as potential inhibitors with a KI values in the range of 10.69±1.27-70.87±8.11 nM for hCA I, 20.01±3.48-56.63±6.41 nM for hCA II, 6.60±0.62-14.15±1.09 nM for acetylcholinesterase (AChE) and 54.87±7.76-137.20 ±9.61 nM for butyrylcholinesterase (BChE). These compounds have a more effective inhibition effect when compared to the reference compounds. In addition, the potential binding positions of the compounds with high affinity for ChE and hCAs were demonstrated by in silico methods. The results of in silico and in vitro studies support each other. As a result of the present study, the compounds with high inhibitory activity for metabolic enzymes, such as ChE and hCA were designed. The compounds may be potential alternative agents used as selective ChE and hCA inhibitors in the treatment of Alzheimer's disease and glaucoma.

Discovery of highly potent SARS-CoV-2 nsp14 methyltransferase inhibitors based on adenosine 5'-carboxamides.

The emergence of SARS-CoV-2, the causative agent of COVID-19, has highlighted the need for advanced antiviral strategies. Targeting the coronaviral methyltransferase nsp14, which is essential for RNA capping, offers a promising approach for the development of small-molecule inhibitors. We designed and synthesized a series of adenosine 5'-carboxamide derivatives as potential nsp14 inhibitors and identified coumarin analogs to be particularly effective. Structural modifications revealed the importance of the 5'-carboxyl moiety for the inhibitory activity, showing superior efficacy compared to other modifications. Notably, compound 18l (HK370) demonstrated high selectivity and favorable in vitro pharmacokinetic properties and exhibited moderate antiviral activity in cell-based assays. These findings provide a robust foundation for developing targeted nsp14 inhibitors as a potential treatment for COVID-19 and related diseases.

Silylacetate-promoted addition reaction of isocyanides to nitrones: effective synthesis of C(1)-carboxamide derivatives.

We report an efficient method for the synthesis of C(1)-carboxamide derivatives by adding isocyanides to 3,4-dihydroisoquinoline N-oxides and 3,4-dihydro-β-carboline 2-oxide in the presence of TMSOAc. 3,4-Dihydroisoquinoline-1-carboxylamide derivatives and 9-dihydro-3H-pyrido[3,4-b]indole-1-carboxamide derivatives were obtained in reasonable yields. The method could be used to synthesize alangiobussine, an alkaloid, in 61% yield.

An Outlook of the Structure Activity Relationship (SAR) of Naphthalimide Derivatives as Anticancer Agents.

The efficacy of drugs against cancer in clinical settings may be limited due to pharmacokinetic issues, side effects and the emergence of drug resistance. However, a class of anticancer drugs known as naphthalimides have proven to be very effective. These derivatives have demonstrated to be effective in treating different types of cancers and exhibit strong DNA binding affinity. The anticancer properties of the naphthalimide derivatives allow them to target a number of cancer cell lines. Researchers have investigated the anticancer activity of numerous naphthalimide derivatives, such as heterocyclic fused, non-fused substituted, metal-substituted and carboxamide derivatives. Surprisingly, some derivatives demonstrate greater activity than the reference norms, such as cisplatin, amonafide, mitonafide and others and are selective against many cell lines. The primary objective of this research is to comprehend the effects of various substitution patterns on the structure-activity relationship (SAR) of these derivatives and the instances in which they enhance or reduce this biological activity.

Design and synthesis of potential pyrrole-coupled carboxamide derivatives as an anti-superbug MRSA agent

A series of new pyrrole-coupled carboxamide derivatives had been synthesized and amply characterized by various techniques, viz FTIR, 1H-NMR, 13C-NMR, and LCMS. All these compounds had undergone evaluation for their PASS, BBB, pharmacophore model, ADME, and bioactive score. The antibacterial properties of all the derivatives were examined and compound 5i demonstrated strong antibacterial activity against MRSA. A membrane damage investigation supported by SEM pictures, cellular content leakage, potassium efflux, and bacterial respiration suppression showed that compound 5i had anti-MRSA properties. A good binding score of -9.11 was found for compound 5i against the MRSA protein 6FTB in an in silico molecular docking analysis, compared to a score of -10.25 for streptomycin. Based on these findings, compound 5i can be further studied in order to develop it as a drug to treat MRSA infections.

Solvent effects on spectroscopic, electronic, and topological analyses, Hirshfeld surface, ADME, and molecular docking studies on antiviral pyridine carboxamide derivatives

A theoretical study of three pyridine carboxamide derivatives in conjunction with the Density Functional Theory (DFT) approach at the 6-311+G(d,p) basis set is presented along with X-ray results. The pyridine carboxamide derivatives were analyzed with the help of FT-IR, UV–Vis, 1H and 13C NMR investigation. The spectral characterizations were made by vibrational energy distribution analysis (VEDA4), which helps to assign vibrational frequencies to specific molecular vibrations. A comparative analysis of computed 1H and 13C NMR chemical shift values with experimental chemical shifts for the pyridine carboxamide compounds by applying the gauge-including atomic orbitals method in chloroform and acetone solvents was carried out. UV–Vis spectroscopy and electronic transitions were conducted on both chloroform and acetone solvents through the assistance of the TD-DFT methodology. Hirshfeld Surface analysis was employed to analyze the intermolecular hydrogen bonds of the type N-H⋯N to the crystal packing. The chemical properties of frontier molecular orbital and global reactivity descriptors were analyzed for the different solvents such as chloroform and acetone. The Fukui functions were used to identify reactive sites in a molecule, including those susceptible to nucleophilic and electrophilic outbreaks. The weak interactions were analyzed using reduced density gradient (RDG) analysis, a computational method used to study noncovalent interactions, including hydrogen bonding. The Absorption, Distribution, Metabolism, and Excretion (ADME) attributes of the studied compounds have been evaluated for drug discovery initiatives. Molecular docking studies with antiviral SARS-CoV-2 Mpro and Omicron variant containing the Q493R mutation proteins of three pyridine carboxamide derivatives (L3–L5) have been performed, and L5 has maximum binding energy values of −7.13 kcal/mol for 6LU7.

Evaluation of Cytotoxicity of 1H-1,2,4-Triazole-3-carboxamide Derivatives in Various Cancer Cell Lines using MTT Assay: Synthesis, Characterization and Molecular Docking Studies

The pursuit of discovering efficacious novel anticancer agents is an ongoing and perpetual endeavour. The ongoing research endeavour involves the discovery of a new set of various substituted 1,2,4-triazole carboxamide derivatives. The synthetic process involves multiple steps: converting thiooxamic acid ethyl ester to ethyl b-N-boc-oxalamidrazone (2), preparing ethyl esters of 5-substituted 1,2,4-triazole-3-carboxylic acid (3) and synthesizing 5-substituted 1,2,4-triazole-3-carboxylic acid amides (4a-n) using potassium tert.-butoxide. The resulting compounds are characterized using 1H and 13C NMR spectroscopy and HRMS. Molecula docking experiments were performed using the synthesized compounds against two cancer targets, viz. EGFR (6LUD) and CDK-4 (7SJ3). The compounds were assessed for their anticancer potential against four different cancer cell lines, namely non-small cell lung cancer (A-549), pancreatic cancer (PANC-1), colorectal cancer (HCT-116) and cervical cancer (HaLa) cell lines. Additionally, a normal human embryonic kidney cell line (HEK-293) was used for comparison. The results obtained from molecular docking analysis demonstrated that the 1,2,4-triazole carboxamides (4c, 4e, 4h, 4m and 4n) exhibited more favourable binding interactions compared to the ligands that were co-crystallized. All the compounds exhibited a satisfactory cytotoxicity profile in comparison to the reference drug doxorubicin. Among the compounds that tested, it was observed that compounds 4e and 4m displayed the most pronounced inhibitory activity across all the cell lines that were tested.

Evaluation of Cytotoxic, COX Inhibitory, and Antimicrobial Activities of Novel Isoxazole-carboxamide Derivatives

Abstract: Isoxazole derivatives are one of the heterocyclic structures that have various biological activities. Objective: This study aimed to design and synthesize novel isoxazole derivatives and evaluate their cytotoxic, cyclooxygenase (COX) inhibitory, and antimicrobial activities. Methods: Coupling reactions of aniline derivatives and isoxazole carboxylic acid have been established to synthesize chloro-fluorophenyl-isoxazole carboxamide derivatives. The synthesized compounds were characterized using 1H, 13C-NMR, IR, and HRMS spectrum analysis and evaluated by MTS, COX kit, and antimicrobial microdilution assays. Results: The synthesized compounds showed moderate to potent cytotoxic activity against all the screened cancer cell lines (except 2b against HepG2) with an IC50 range of 0.107-77.83 μg/ml. The results showed that the most potent compound against cervical cancer cell line (HeLa) was the 2b compound, with an IC50 value of 0.11±0.10 μg/ml, which is less than the IC50 for the potent anticancer drug Doxorubicin. While the 2a and 2b compounds have potential antiproliferative activities against Hep3B with IC50 doses of 2.774±0.53 and 3.621±1.56 μg/ml, respectively. Furthermore, 2c compound was the most active against MCF7, with an IC50 value of 1.59±1.60 μg/ml. In addition, the most potent isoxazole derivative against the COX1 enzyme was the 2b compound, with an IC50 value of 0.391 μg/ml, and compound 2a had a good selectivity ratio of 1.44 compared to the Ketoprofen positive control. However, compound 2c showed antifungal activity against Candida albicans with an MIC value of 2.0 mg/ml in comparison to the antifungal drug Fluconazole (MIC = 1.65 mg/ml). Conclusion: The synthesized compounds could be candidates for anticancer drugs in the future, and other analogues and cytotoxicity evaluations should be conducted.

Thiazole Derivatives as Modulators of GluA2 AMPA Receptors: Potent Allosteric Effects and Neuroprotective Potential.

Thiazole carboxamide derivatives were synthesized in this investigation, with a subsequent examination of their impact on GluA2 AMPA receptors. The synthesized compounds, namely MMH-1-5, were subjected to characterization using high-resolution mass spectrometry (HRMS), proton nuclear magnetic resonance (1H-NMR), and carbon-13 nuclear magnetic resonance (13C-NMR). The present work thoroughly investigates the impact of five thiazole derivatives on GluA2 AMPA receptors. This investigation examined their effects on both whole-cell currents and receptor kinetics. In addition, the cytotoxicity of the samples was assessed using the MTS test. The compound MMH-5 had the highest effect level, resulting in a notable drop in current amplitude by a factor of six. Similarly, MMH-4 and MMH-3 also caused major reductions in the current amplitude. The compounds mentioned above also influenced the rates of deactivation and desensitization. MMH-5 and MMH-4 exhibited an increase in deactivation, while MMH-5 showed reduced desensitization. Our research findings highlight the efficacy of MMH-5 as a negative allosteric modulator of GluA2 AMPA receptors, exerting substantial effects on both the magnitude and time course of receptor activity. Significantly, the compound MMH-2 demonstrated noteworthy cytotoxic effects, as evidenced by cell viability rates dropping below 6.79% for all cancer cell lines and 17.52% for the normal cell line (LX-2). Of particular interest is the pronounced cytotoxicity observed in MMH-5, suggesting its potential as a safe neuroprotective agent targeting the AMPA receptor, as indicated by cell viability percentages exceeding 85.44% across all cancer and normal cell lines. Docking simulations were performed to determine possible modes of interaction between MMH5 and the GluA2-AMPA receptor (PDB:7RZ5). The abovementioned facts and the well-documented effects of further thiazole derivatives provide a strong foundation for future research endeavors to enhance tailored treatments for neurological disorders that rely heavily on GluA2 signaling. The present study elucidates the intricate association between thiazole derivatives and GluA2 receptors, providing valuable perspectives on the prospects of enhanced and specific therapeutic interventions for diverse neurological conditions.

New oxindole carboxamides as inhibitors of DENV NS5 RdRp: Design, synthesis, docking and Biochemical characterization

Dengue is a mosquito-borne disease caused by the dengue virus belonging to family flaviviridae and has grown to be a major global public health issue. Despite decades of effort, the global comeback of dengue is evidence of the inadequacy of present management techniques. Due to the loss of healthy lives and the depletion of scarce medical resources, dengue has a significant negative economic impact in underdeveloped countries. In recent years, research for tackling the incidences of dengue infection has increased. The structure of the viral genome has been deciphered with the non-structural protein, known as NS5 serving as a potential target. NS5 consisting of an MTase domain involved in RNA capping and an RdRp domain involved in viral replication. In the presented work, a series of new Oxindoline Carboxamide derivatives were designed and synthesized for inhibiting the viral RNA dependent RNA-polymerase (RdRp) activity of DENV. The novel compounds were put through tests including molecular docking and surface plasmon resonance (SPR) binding analysis to evaluate their affinity for the viral protein and their potential as novel inhibitors of the virus. From a total of 12 derivative compounds, four compounds OCA-10c, OCA-10f, OCA-10j &OCA-10i, were found to exhibit high affinity for NS5 RdRp, the KD values being 1.376 μM, 1.63 μM, 7.08 μM & 9.32 μM respectively. Overall, we report novel inhibitors of DENV RdRp activity with potential to be utilized against DENV for treating humans after further optimization.

Structure-based drug discovery of novel fused-pyrazolone carboxamide derivatives as potent and selective AXL inhibitors

As a novel and promising antitumor target, AXL plays an important role in tumor growth, metastasis, immunosuppression and drug resistance of various malignancies, which has attracted extensive research interest in recent years. In this study, by employing the structure-based drug design and bioisosterism strategies, we designed and synthesized in total 54 novel AXL inhibitors featuring a fused-pyrazolone carboxamide scaffold, of which up to 20 compounds exhibited excellent AXL kinase and BaF3/TEL-AXL cell viability inhibitions. Notably, compound 59 showed a desirable AXL kinase inhibitory activity (IC50: 3.5 nmol/L) as well as good kinase selectivity, and it effectively blocked the cellular AXL signaling. In turn, compound 59 could potently inhibit BaF3/TEL-AXL cell viability (IC50: 1.5 nmol/L) and significantly suppress GAS6/AXL-mediated cancer cell invasion, migration and wound healing at the nanomolar level. More importantly, compound 59 oral administration showed good pharmacokinetic profile and in vivo antitumor efficiency, in which we observed significant AXL phosphorylation suppression, and its antitumor efficacy at 20 mg/kg (qd) was comparable to that of BGB324 at 50 mg/kg (bid), the most advanced AXL inhibitor. Taken together, this work provided a valuable lead compound as a potential AXL inhibitor for the further antitumor drug development.

Characterization and Investigation of Novel Benzodioxol Derivatives as Antidiabetic Agents: An In Vitro and In Vivo Study in an Animal Model.

In this study, we synthesized benzodioxol carboxamide derivatives and investigated their antidiabetic potential. The synthesized compounds (Ia-Ic and IIa-IId) underwent characterization via HRMS, 1H-, 13CAPT-NMR, and MicroED. Their efficacy against α-amylase was assessed in vitro, while MTS assays were employed to gauge cytotoxicity across cancer and normal cell lines. Additionally, the antidiabetic impact of compound IIc was evaluated in vivo using a streptozotocin-induced diabetic mice model. Notably, IIa and IIc displayed potent α-amylase inhibition (IC50 values of 0.85 and 0.68 µM, respectively) while exhibiting a negligible effect on the Hek293t normal cell line (IC50 > 150 µM), suggesting their safety. Compound IId demonstrated significant activity against four cancer cell lines (26-65 µM). In vivo experiments revealed that five doses of IIc substantially reduced mice blood glucose levels from 252.2 mg/dL to 173.8 mg/dL in contrast to the control group. The compelling in vitro anticancer efficacy of IIc and its safety for normal cells underscores the need for further in vivo assessment of this promising compound. This research highlights the potential of benzodioxol derivatives as candidates for the future development of synthetic antidiabetic drugs.

Potential anti-amoebic activity of sulfonate- and sulfamate-containing carboxamide derivatives against pathogenic Acanthamoeba castellanii belonging to the genotype T4

Acanthamoeba are ubiquitously distributed in the environment and can cause infection of the central nervous system as well a sight-threatening eye infection. Herein, the potential anti-amoebic activity of a series of sulfonate/sulfamate derivatives against pathogenic A. castellanii was evaluated. These compounds were tested using several assays namely amoebicidal, adhesion, excystation, cytotoxic, and cytopathogenicity. Amoebicidal assays revealed that the selected compounds reduced amoebae viability significantly (P < 0.05), and exhibited IC50 values at two-digit micromolar concentrations. Sulfamate derivatives 1j &1k inhibited 50% of amoebae at 30.65 μM and 27.21 μM, respectively. The tested compounds blocked amoebae binding to host cells as well as inhibited amoebae excystation. Notably, the selected derivatives exhibited minimal human cell cytotoxicity but reduced parasite-mediated host cell damage. Overall, our study showed that sulfamate derivatives 1j &1k have anti-amoebic potential and offer a promising avenue in the development of potential anti-amoebic drug candidates.

Unexpected products using Biginelli reaction: Synthesis, antimicrobial potency, docking simulation, and DFT investigations of some new amidopyridines

The Biginelli reaction of 3-oxo-N-(2-pyridyl)butanamide with thiourea (or urea) and some aromatic aldehydes afforded new chemical skeletons containing tetrahydropyrimidine, pyridine, and carboxamide pharmacophoric moieties. The expected products of this reaction were not isolated in the case of 4-nitrobenzaldehyde, pyridine-2-carbaldehyde, and thiophene-2-carbaldehyde; rather the corresponding acrylamide derivatives were obtained. Chemical structures of the newly synthesized hybrids were elucidated by FT-IR, NMR spectroscopy in addition to mass spectrometry and elemental analyses. The in-vitro antimicrobial activity showed that the products were highly active against the tested pathogens that were confirmed through molecular docking simulation with different proteins such as PDBID:3t88, 2wje, 1tgh, and 4ynt which showed a different binding affinity with attraction of amino acids of proteins. Furthermore, the optimization of different pyridine carboxamides utilized a DFT/B3LYP-6311(G) basis set to know the cyclization of butanamide 1 with thiourea and different aldehydes in the presence of electron-donating/withdrawing groups which affected of the expected products with different transition states. Moreover, the determination of the energy gap and physical descriptors of these pyridine carboxamide derivatives showed the stability of tetrahydropyrimidines 2a,b due to the presence of donating groups which enhanced the activity and stability. Determination of the ESP and MEP of compounds 2a,b confirmed a correlation with biological evaluations.

Discovery of Novel Carboxamide Derivatives Containing Biphenyl Pharmacophore as Potential Fungicidal Agents Used for Resistance Management.

Natural products are one of the main sources of drug and agrochemicals discovery. Biphenyls skeleton are ubiquitous structures in many classes of natural products, which indicate extensive biological activities. So, in order to investigate the potential applications for natural biphenyl derivatives, a series of novel carboxamide derivatives with diverse substituent patterns were designed and synthesized based on active pharmacophore from natural biphenyl lignans, and their in vitro antifungal activities against several typical plant pathogens belonging to oomycetes, ascomycete, deuteromycetes, and basidiomycetes were fully investigated. The highly potential compounds were further tested in vivo assay against Botrytis cinerea Pers. of cucumber to demonstrate a practical application for controlling common plant diseases, which indicated four compounds could effectively control the resistant strains of carbendazim, rutamycin, and pyrazolidide. The potential modes of action for compound B12 against B. cinerea were also explored using molecular docking, microscopic technology, and label-free quantitative proteomics analysis. The results show that compound B12 may be a potential novel fungicidal agent used for gray mold resistance control, which can influence the protein synthesis of B. cinerea. These findings can provide a certain theoretical basis for the development of novel biphenyl derivatives as potential green antifungal agents.

The anti-amoebic potential of carboxamide derivatives containing sulfonyl or sulfamoyl moieties against brain-eating Naegleria fowleri.

Naegleria fowleri is a free-living thermophilic flagellate amoeba that causes a rare but life-threatening infection called primary amoebic meningoencephalitis (PAM), with a very high fatality rate. Herein, the anti-amoebic potential of carboxamide derivatives possessing sulfonyl or sulfamoyl moiety was assessed against pathogenic N. fowleri using amoebicidal, cytotoxicity and cytopathogenicity assays. The results from amoebicidal experiments showed that derivatives dramatically reduced N. fowleri viability. Selected derivatives demonstrated IC50 values at lower concentrations; 1j showed IC50 at 24.65 μM, while 1k inhibited 50% amoebae growth at 23.31 μM. Compounds with significant amoebicidal effects demonstrated limited cytotoxicity against human cerebral microvascular endothelial cells. Finally, some derivatives mitigated N. fowleri-instigated host cell death. Ultimately, this study demonstrated that 1j and 1k exhibited potent anti-amoebic activity and ought to be looked at in future studies for the development of therapeutic anti-amoebic pharmaceuticals. Further investigation is required to determine the clinical relevance of our findings.

Synthesis and biological evaluation of carboxamide and quinoline derivatives as P2X7R antagonists

P2X7 receptor (P2X7R) has a key role in different pathological conditions, importantly overexpressed and activated in cancers. We explored the structure activity relationship (SAR) of three novel pyrazines, quinoline-carboxamide and oxadiazole series. Their selective inhibitory potency in Ca2+ mobilization assay using h-P2X7R-MCF-7 cells improved with phenyl ring substitutions (–OCF3, –CF3, and –CH3) in carboxamide and oxadiazole derivatives, respectively. However, highly electronegative fluoro, chloro, and iodo substitutions enhanced affinity. 1e, 2f, 2e, 1d, 2 g and 3e were most potent and selective toward h-P2X7R (IC50 values 0.457, 0.566, 0.624, 0.682, 0.813 and 0.890 µM, respectively) and were inactive at h-P2X4R, h-P2X2R, r-P2Y6R, h-P2Y2R, t-P2Y1R expressed in MCF-7 and 1321N1 astrocytoma cells. Cell viability (MTT assay at 100 µM, cell line) for 3e was 62% (HEK-293T), 70% (1321N1 astrocytoma) and 85% (MCF-7). >75% cell viability was noted for 2 g and >80% for 2e and 1d in all non-transfected cell lines. Anti-proliferative effects, compared to control (Bz-ATP), of selective antagonists (10 µM) were 3e (11%) 1d, (19%) 1e, (70%, P = 0.005) and 2f, (24%), indicating involvement of P2X7R. Apoptotic cell death by flow cytometry showed 1e to be most promising, with 35% cell death (PI positive cells), followed by 2e (25%), 2f (20%), and 1d (19%), compared to control. Fluorescence microscopic analysis of apoptotic changes in P2X7R-transfected cell lines was established. 1e and 2f at 1X and 2X IC50 increased cellular shrinkage, nuclear condensation and PI/DAPI fluorescence. In-silico antagonist modeling predicted ligand receptor interactions, and all compounds obeyed Lipinski rules. These results suggest that pyrazine, quinoline-carboxamide and oxadiazole derivatives could be moderately potent P2X7R antagonists for in vivo studies and anti-cancer drug development.

Synthesis of Novel Carboxamide Derivatives: Insecticidal Activity, Acetylcholinesterase Activity and In Silico Calculations

The insecticidal activity of carboxamide derivatives was investigated against both larvae and adults of Myzus percisace (Sulzer) (Hemiptera: Aphididae), Leptinotarsa decemlineata (Coleoptera: Chrysomelidae), and Trialeurodes vaporariorum (Hemiptera: Aleyrodidae) in different concentrations. The synthesized compounds were obtained good yield, and their molecular structures were confirmed by FTIR, NMR, and MALDI-TOF/MS. The compound 3o was found to be the most active against Leptinotarsa decemlineata adults, while the compound 3l was found against larvae. Furthermore, the compounds were evaluated against acetylcholinesterase (AChE) enzyme, and two of the compounds (3n and 3o) showed moderate inhibitory effect against both commercial acetylcholinesterase (0.18 ± 0.01 and 0.13 ± 0.01 μM) and M. percisace adult homogenate (0.65 ± 0.02 and 0.24 ± 0.01 μM), respectively. In silico molecular docking and ADME properties were performed.