Synthesis and pharmacological evaluation of some 3-phenyl-2-substituted-3H-quinazolin-4-one as analgesic, anti-inflammatory agents

Design, synthesis, X-ray crystal structure, and antimicrobial evaluation of novel quinazolinone derivatives containing the 1,2,4-triazole Schiff base moiety and an isopropanol linker

A series of novel quinazolinone derivatives (E1-E31) containing the 1,2,4-triazole Schiff base moiety and an isopropanol linker were designed, synthesized and assessed as antimicrobial agents in agriculture. All the target compounds were fully characterized by 1 H NMR, 13 C NMR, and high-resolution mass spectrometry (HRMS). Among them, the structure of compound E12 was further confirmed via single crystal X-ray diffraction method. The experimental results indicated that many compounds displayed good in vitro antibacterial efficacies against the tested phytopathogenic bacteria including Xanthomonas oryzae pv. oryzae (Xoo), Xanthomonas axonopodis pv. citri (Xac), and Ralstonia solanacearum (Rs). For example, compounds E3, E4, E10, E13, and E22 had EC50 (half-maximal effective concentration) values of 55.4, 39.5, 49.5, 53.5, and 57.4 µg/mL against Xoo, respectively, superior to the commercialized bactericide Bismerthiazol (94.5 µg/mL). In addition, the antibacterial efficacies of compounds E10 and E13 against Xac were about two times more effective than control Bismerthiazol, in terms of their EC50 values. Last, the antifungal assays showed that compounds E22 and E30 had the inhibition rates of 52.7% and 54.6% at 50 µg/mL against Gibberella zeae, respectively, higher than the commercialized fungicide Hymexazol (48.4%).

[DDQM][HSO4]/TBHP as a Multifunctional Catalyst for the Metal Free Tandem Oxidative Synthesis of 2-Phenylquinazolin-4(3H)-ones

A bifunctional ionic liquid (IL) [DDQM][HSO4] has been designed and explored as a three-way catalyst for the synthesis of 2-phenylquinazolin-4(3H)-ones from anthranilamide and benzyl alcohol in 3.5 min incorporating microwave irradiation. Photochemically the reaction proceeds for 4 h at room temperature and thermally for 8 h at 120 °C. Further IL-assisted metal, solvent, and base free in situ oxidation of benzyl alcohols to aldehydes shows its task specificity. The multifunctionality of the IL was reestablished with the synthesis of two Wnt pathway antagonists.

Functionalization Strategies for Electropolishing Process of Carbon Steel Using Novel Quinazoline-4-one Derivatives: Synthesis, Spectroscopic Characterization, and DFT Studies

A novel class of organic electropolishing (EP) inhibitors, entitled quinazoline-4-one derivatives (benzylidene oxoquinazolineyl acetohydrazide (BOA)), has laid a solid foundation for the creation of a new efficient inhibitor platform for the dissolution of carbon steel (C-steel) in 8 M H3PO4. Fourier-transform infrared (FTIR), 1H NMR, and elemental analyses have all been employed to identify BOA's functional groups, components, and active centers. The inhibition strength of BOA derivatives (m-NBOA, p-HBOA, and p-BBOA) on C-steel was assured by galvanostatic polarization measurements. Within the range of concentrations (0.33-3.43 × 10-3 mol/L) and temperatures (298-313 K) evaluated, the tested derivatives exhibit extraordinarily high gloss and low roughness, and improved the corrosion resistance of the electropolished surface with the lowest negative environmental impact. The dissolution rate (IL) decreases with increasing BOA concentration, supporting a mass transport-controlled technique and demonstrating that BOA is appropriate for anodic inhibitors. Activation energy indicates physical adsorption. Thermodynamic parameters were calculated for further investigation of the heat involved and the mechanism of the EP process. Adsorption isotherm and adsorption thermodynamics parameters were discussed using three models: Langmuir, Flory-Huggins, and kinetic adsorption isotherms, to study the inhibition of EP of the steel surface. The free energy of adsorption was calculated to assert the physisorption process. A scanning electron microscope (SEM) was utilized to inspect the morphology of the metal surface before and after the inclusion of BOA under different conditions. In contrast, the surface roughness was identified using an atomic force microscope (AFM) and reflectance. Eventually, practical results have been proved through computational calculations using the LYP correlation functional by the density functional theory (DFT) method.

Quinolinones Alkaloids with AChE Inhibitory Activity from Mangrove Endophytic Fungus Penicillium citrinum YX-002

Acetylcholinesterase (AChE) inhibitory activity-guided studies on the mangrove-derived endophytic fungus Penicillium citrinum YX-002 led to the isolation of nine secondary metabolites, including one new quinolinone derivative, quinolactone A (1), a pair of epimers quinolactacin C1 (2) and 3-epi-quinolactacin C1 (3), together with six known analogs (4-9). Their structures were elucidated based on extensive mass spectrometry (MS) and 1D/2D nuclear magnetic resonance (NMR) spectroscopic analyses, and compared with data in the literature. The absolute configurations of compounds 1-3 was determined by combination of electronic circular dichroism (ECD) calculations and X-Ray single crystal diffraction technique using CuKα radiation. In bioassays, compounds 1, 4 and 7 showed moderate AChE inhibitory activities with IC50 values of 27.6, 19.4 and 11.2 μmol/L, respectively. The structure-activity relationships (SARs) analysis suggested that the existence of carbonyl group on C-3 and the oxygen atom on the five-membered ring were beneficial to the activity. Molecular docking results showed that compound 7 had a lower affinity interaction energy (-9.3 kcal/mol) with stronger interactions with different sites in AChE activities, which explained its higher activities.

An Aldehyde-Driven, Fe(0)-Mediated, One-Pot Reductive Cyclization: Direct Access to 5,6-Dihydro-quinazolino[4,3-b]quinazolin-8-ones and Photophysical Study

A short, proficient, and regioselective synthesis of biheterocyclic 5,6-dihydro-quinazolino[4,3-b]quinazolin-8-ones has been revealed via an Fe(0)-powder-mediated, one-pot reductive cyclization protocol. Mechanistic investigation proved that water acts as a source of hydrogen for the reduction of the nitro group and the reaction rate was accelerated by an aldehyde. The designed transformation works under aerobic conditions, providing a series of bio-inspired molecular scaffolds. In addition, the photophysical study showed blue fluorescence emission with a good fluorescence quantum yield.

The Synthesis and Biological Evaluation of 2-(1H-Indol-3-yl)quinazolin-4(3H)-One Derivatives

The treatment of many bacterial diseases remains a significant problem due to the increasing antibiotic resistance of their infectious agents. Among others, this is related to Staphylococcus aureus, especially methicillin-resistant S. aureus (MRSA) and Mycobacterium tuberculosis. In the present article, we report on antibacterial compounds with activity against both S. aureus and MRSA. A straightforward approach to 2-(1H-indol-3-yl)quinazolin-4(3H)-one and their analogues was developed. Their structural and functional relationships were also considered. The antimicrobial activity of the synthesized compounds against Mycobacterium tuberculosis H₃₇Rv, S. aureus ATCC 25923, MRSA ATCC 43300, Candida albicans ATCC 10231, and their role in the inhibition of the biofilm formation of S. aureus were reported. 2-(5-Iodo-1H-indol-3-yl)quinazolin-4(3H)-one (3k) showed a low minimum inhibitory concentration (MIC) of 0.98 μg/mL against MRSA. The synthesized compounds were assessed via molecular docking for their ability to bind long RSH (RelA/SpoT homolog) proteins using mycobacterial and streptococcal (p)ppGpp synthetase structures as models. The cytotoxic activity of some synthesized compounds was studied. Compounds 3c, f, g, k, r, and 3z displayed significant antiproliferative activities against all the cancer cell lines tested. Indolylquinazolinones 3b, 3e, and 3g showed a preferential suppression of the growth of rapidly dividing A549 cells compared to slower growing fibroblasts of non-tumor etiology.

Medicinal Chemistry of Quinazolines as Analgesic and Anti-Inflammatory Agents

Quinazoline is an essential scaffold, known to be linked with various biological activities. Some of the prominent biological activities of this system are analgesic, anti-inflammatory, anti-hypertensive, anti-bacterial, anti-diabetic, anti-malarial, sedative–hypnotic, anti-histaminic, anti-cancer, anti-convulsant, anti-tubercular, and anti-viral activities. This diversity in the pharmacological response of the quinazoline system has encouraged medicinal chemists to study and discover this system and its multitude of potential against several biological activities. Many of these studies have successfully investigated the structure–activity relationship to explore the specific structural features of their biological targets. The developing understanding of quinazoline derivatives and their biological targets presents opportunities for the discovery of novel therapeutics. This review represents different aspects of medicinal chemistry, including drug design, structure–activity relationship, and the mode of action of some analgesic and anti-inflammatory quinazoline compounds. It pays comprehensive attention to the analgesic and anti-inflammatory activities of quinazolines from the viewpoint of drug discovery and its development.

Synthesis of Alicyclic 2-Methylenethiazolo[2,3-b]quinazolinone Derivatives via Base-Promoted Cascade Reactions

The synthesis of alicyclic 2-methylenethiazolo[2,3-b]quinazo­l­inones is performed via base-promoted cascade reactions, starting from either alicyclic β-amino propargylamides using carbon disulfide, or from alicyclic ethyl 2-isothiocyanatocarboxylates by addition of propargylamine. In both cases the cascade reaction proceeds by way of a favoured 5-exo-dig process during the second ring closure, as confirmed by full NMR spectroscopic assignments. Moreover, a high-yielding retro­-Diels–Alder (RDA) reaction is performed on the norbornene derivatives leading to 2-methylene-2H-thiazolo[3,2-a]pyrimidin-5(3H)-ones. The obtained compounds exert modest antiproliferative activities against a panel of human gynaecological cancer cell lines.

Crystal structures of 6-nitro-quinazolin-4(3H)-one, 6-amino-quinazolin-4(3H)-one and 4-amino-quinazoline hemi-hydro-chloride dihydrate

6-Nitro­quinazolin-4(3H)-one (C₈H₅N₃O₃), 6-amino­quinazolin-4(3H)-one (C₈H₇N₃O) and 4-amino­quinazoline hemi­hydro­chloride dihydrate (C₁₆H₁₉N₆O₂) were synthesized and their structures were determined by single-crystal X-ray analysis.

The title compounds, 6-nitro­quinazolin-4(3H)-one (C₈H₅N₃O₃; I), 6-amino­quinazolin-4(3H)-one (C₈H₇N₃O; II) and 4-amino­quinazolin-1-ium chloride–4-amino­quinazoline–water (1/1/2), (C₈H₈N₃⁺·Cl⁻·C₈H₇N₃·2H₂O; III) were synthesized and their structures were determined by single-crystal X-ray analysis. In the crystals of I and II, the quinazoline mol­ecules form hydrogen-bonded dimers via N—H⋯O inter­actions. The dimers are connected by weak inter­molecular C—H⋯N and C—H⋯O hydrogen bonds, forming a layered structure in the case of I. In the crystal of II, N—H⋯N and C—H⋯O inter­actions link the dimers into a three-dimensional network structure. The asymmetric unit of III consists of two quinazoline mol­ecules, one of which is protonated, a chloride ion, and two water mol­ecules. The chloride anion and the water mol­ecules form hydrogen-bonded chains consisting of fused five-membered rings. The protonated and unprotonated quinazolin mol­ecules are linked to the chloride ions and water mol­ecules of the chain by their amino groups.

Quinazolin-derived myeloperoxidase inhibitor suppresses influenza A virus-induced reactive oxygen species, pro-inflammatory mediators and improves cell survival

Superoxide radicals and other reactive oxygen species (ROS) are implicated in influenza A virus-induced inflammation. In this in vitro study, we evaluated the effects of TG6-44, a novel quinazolin-derived myeloperoxidase-specific ROS inhibitor, on influenza A virus (A/X31) infection using THP-1 lung monocytic cells and freshly isolated peripheral blood mononuclear cells (PBMC). TG6-44 significantly decreased A/X31-induced ROS and virus-induced inflammatory mediators in THP-1 cells (IL-6, IFN-γ, MCP-1, TNF-α, MIP-1β) and in human PBMC (IL-6, IL-8, TNF-α, MCP-1). Interestingly, TG6-44-treated THP-1 cells showed a decrease in percent cells expressing viral nucleoprotein, as well as a delay in translocation of viral nucleoprotein into the nucleus. Furthermore, in influenza A virus-infected cells, TG6-44 treatment led to suppression of virus-induced cell death as evidenced by decreased caspase-3 activation, decreased proportion of Annexin V⁺PI⁺ cells, and increased Bcl-2 phosphorylation. Taken together, our results demonstrate the anti-inflammatory and anti-infective effects of TG6-44.

Design, synthesis, and pharmacological characterization of some 2-substituted-3-phenyl-quinazolin-4(3H)-one derivatives as phosphodiesterase inhibitors

Some 3-phenyl-quinazolin-4(3H)-one-2-thioethers (3a-e, 5a,b, 7a-e, 9a-d, 10a-d, and 12) along with 2-aminoquinazoline derivatives 13a-c were prepared and screened for their in vitro phosphodiesterase (PDE) inhibitory activity. Some compounds such as 7d,e, 9a,b,d, 10a,d, and 13b exhibited promising activity as compared with the non-selective PDE inhibitor IBMX. This inhibitory activity was validated by molecular docking in the active site of PDE7A and PDE4 to investigate their selectivity. Furthermore, the most active compound 10d (IC₅₀  = 1.15 μM) was tested in vivo using behavioral tests. Compound 10d was able to pass the blood-brain barrier and improve scopolamine-induced cognitive deficits. Therefore, this core can be considered as a promising scaffold for further optimization to obtain new compounds with better PDE7A selective inhibition.

Synthesis, characterization, biological evaluation and molecular docking of a new quinazolinone-based derivative as a potent dual inhibitor for VEGFR-2 and EGFR tyrosine kinases

An efficient process for the preparation of a new ethyl 2-((3-(4-fluorophenyl)-6-methyl-4-oxo-3,4-dihydroquinazolin-2-yl)thio) acetate (5) was described. The prepared derivative was synthesized using the S-arylation method. Several analytical techniques, such as NMR, Raman and infrared spectroscopy, were used to characterize this compound. The compound was screened for cytotoxic activity against three human cancer cell lines: human cervical cancer (HeLa), human lung adenocarcinoma (A549) and triple negative breast cancer (MDA-MB-231) cells using an MTT assay. It exhibited potent cytotoxic activity against the tested cell lines with IC₅₀ values in the low micromolar range when compared to a standard drug, docetaxel. It also displayed potent inhibitory activity towards VEGFR-2 and EGFR tyrosine kinases, reflecting its potential to act as an effective anti-cancer agent.Communicated by Ramaswamy H. Sarma.

A palladium-catalyzed cascade process for spirooxindole: an alternative way for the synthesis of spiro(indoline-3,2'-quinazolin)-2-ones

A palladium-catalyzed cascade strategy has been developed for one-pot synthesis of functionalized spiro(indoline-3,2'-quinazolin)-2-one derivatives from readily available starting materials. The reaction proceeds via C-C and two C-N bond formations in a single reaction operation. This method offers an attractive pathway for the synthesis of a broad range of spiro(indoline-3,2'-quinazolin)-2-ones in good yields.

Synthesis and Anti-Proliferative Evaluations of New Heterocyclic Derivatives Using 5,6,8,9-Tetrahydropyrazolo[5,1-b]quinazolin-7(3H)-one Derivatives Derived from Cyclohexa-1,4-dione

BACKGROUND

Recentlty, pyrazoloquinazoline derivatives acquired a special attention due to their wide range of pharmacological activities, especially therapeutic. Through the market, it was found that many pharmacological drugs containing the quinazoline nucleus were known.

OBJECTIVE

The aim of this work is to synthesize target molecules possessing not only anti-tumor activities but also kinase inhibitors. The target molecules were obtained through the synthesis of a series of 5,6,8,9- tetrahydropyrazolo[5,1-b]quinazolin-7(3H)-one derivatives 4a-i using the multi-component reactions of cyclohexane- 1,4-dione (1), the 5-amino-4-(2-arylhydrazono)-4H-pyrazol-3-ol derivatives 2a-c, the aromatic aldehydes 3a-c, respectively. The synthesized compounds were evaluated against c-Met kinase, PC-3 cell line, and different kinds of cancer cell lines together with normal cell line, tyrosine kinases, and Pim-1 kinase.

METHODS

Multi-component reactions were adopted using compound 1 to get different 5,6,8,9- tetrahydropyrazolo[5,1-b]quinazolin-7(3H)-one derivatives which underwent further heterocyclization reactions. The c-Met kinase activity of all compounds was evaluated using Homogeneous Time-Resolved Fluorescence (HTRF) assay, taking foretinib as the positive control. The anti-proliferative activity of all target compounds against the human prostatic cancer PC-3 cell line was measured using MTT assay using SGI-1776 as the reference drug. All the synthesized compounds were assessed for inhibitory activities against A549 (non-small cell lung cancer), H460 (human lung cancer), HT-29 (human colon cancer), and MKN-45 (human gastric cancer) cancer cell lines together with foretinib as the positive control by an MTT assay.

RESULTS

Antiproliferative evaluations and c-Met kinase, Pim-1 kinase inhibitions were performed for the synthesized compounds, where the varieties of substituents through the aryl ring and the thiophene moiety afforded compounds with high activities.

CONCLUSION

The compounds with high antiproliferative activity were tested towards c-Met and the results showed that compounds 4e, 4f, 4g, 4i, 6i, 6k, 6l, 8f, 8i, 10d, 10e, 10f, 10h, 12e, 12f, 12g, 12h, 12i, 14f, 14g, 14h, and 14i were the most potent compounds. A further selection of compounds for the Pim-1 kinase inhibition activity showed that compounds 4f, 6i, 6l, 8h, 8i, 8g, 10d, 12i, and 14f were the most active compounds to inhibit Pim-1.

Synthesis, Antibacterial, and Antioxidant Evaluation of Novel Series of Condensed Thiazoloquinazoline with Pyrido, Pyrano, and Benzol Moieties as Five- and Six-Membered Heterocycle Derivatives

A novel synthesis of thiazolo[2,3-b]quinazolines 4(a–e), pyrido[2′,3′:4,5]thiazolo[2,3-b]quinazolines {5(a–e), 6(a–e), and 7(a–e)}, pyrano[2′,3′:4,5]thiazolo[2,3-b]quinazolines 8(a–e), and benzo[4,5]thiazolo[2,3-b]quinazoloine9(a–e) derivatives starting from 2-(Bis-methylsulfanyl-methylene)-5,5-dimethyl-cyclohexane-1,3-dione 2 as efficient α,α dioxoketen dithioacetal is reported and the synthetic approaches of these types of compounds will provide an innovative molecular framework to the designing of new active heterocyclic compounds. In our study, we also present optimization of the synthetic method along with a biological evaluation of these newly synthesized compounds as antioxidants and antibacterial agents against the bacterial strains, like S. aureus, E. coli, and P. aeruginosa. Among all the evaluated compounds, it was found that some showed significant antioxidant activity at 10 μg/mL while the others exhibited better antibacterial activity at 100 μg/mL. The results of this study showed that compound 6(c) possessed remarkable antibacterial activity, whereas compound 9(c) exhibited the highest efficacy as an antioxidant. The structures of the new synthetic compounds were elucidated by elemental analysis, IR, ¹H-NMR, and ¹³C-NMR.

Design, synthesis, biological activities and 3D-QSAR studies of quinazolinone derivatives containing hydrazone structural units

A series of novel quinazolinone derivatives containing hydrazone structural units were synthesized and their antitumour activities were evaluated.

UiO-66-NH2 as an effective solid support for quinazoline derivatives for antibacterial agents against Gram-negative bacteria

UiO-66-NH2 is used as an effective drug carrier for the control of quinazoline release for antibacterial agents against Gram-negative bacteria.

Synthesis of 2-aryl quinazolinones via iron-catalyzed cross-dehydrogenative coupling (CDC) between N-H and C-H bonds

Herein, we describe the direct synthesis of quinazolinones via cross-dehydrogenative coupling between methyl arenes and anthranilamides. The C-H functionalization of the benzylic sp3 carbon is achieved by di-t-butyl peroxide under air, and the subsequent amination-aerobic oxidation process completes the annulation process. Iron catalyzed the whole reaction process and various kinds of functional groups were tolerated under the reaction conditions, providing 31 examples of 2-aryl quinazolinones using methyl arene derivatives in yields of 57-95%. The synthetic potential has been demonstrated by the additional synthesis of aryl-containing heterocycles.

Visible-Light-Mediated Intermolecular Radical Conjugate Addition for the Construction of Vicinal Quaternary Carbon Centers

The visible light-driven organophotoredox catalysis is reported for the construction of vicinal quaternary carbon centers. Intermolecular conjugate addition of alkyl radicals, derived from 2,2-disubstituted dihydroquinazolinones, to Michael acceptors under blue light irradiation and rhodamine B catalysis allows the facile assembly of diverse, vicinal secondary/quaternary, tertiary/quaternary, and quaternary/quaternary carbon centers at room temperature. Our method provides a synthetically versatile protocol since both 2,2-disubstituted dihydroquinazolinones and Michael acceptors can be conveniently prepared from readily available ketones.

Synthesis of novel 2, 3, 5-tri-substituted thiazoles with anti-inflammatory and antibacterial effect causing clinical pathogens

BACKGROUND

The present work is an extension of ongoing efforts toward the development and identification of new molecules as monotherapy displaying anti-inflammatory and anti-infective activities and a wide-range of gastrointestinal selectivity. A series of novel set of trisubstituted thiazole compounds (AR-17a to AR-27a) have synthesized and evaluated for their in-vitro and in-vivo anti-inflammatory activities. Synthesized trisubstituted thiazole compounds were also evaluated for their potential antibacterial activity against clinical pathogens causing infectious disease.

MATERIAL AND METHOD

The structures of synthesized compounds were characterized by FTIR, ¹H NMR, Mass spectroscopic techniques and evaluated for their in-vitro and in-vivo anti-inflammatory effects using the human red blood cell (HRBC) membrane stabilization method and a carrageenan-induced rat paw oedema model, respectively, Diclofenac sodium and Ibuprofen were used as standard drugs. The synthesized compounds AR-17atoAR-27a screened for their in-vitro antibacterial activity against the gram-positive bacteria Staphylococcus aureus (ATCC25923) and Enterococcus faecalis (ATCC29212) and the gram-negative bacteria Escherichia coli (ATCC8739) and Pseudomonas aeruginosa (ATCC9027) using ciprofloxacin and cefdinir as standard drugs.

RESULT

Compounds AR-17a and AR-27a elicited maximum anti-inflammatory activity, providing 59% and 61% protection at 20mg/kg, respectively, in the inflamed paw model. Among the tested compounds, AR-17a (6.25), (54) and AR-27a (1.56), (52) had the least minimum inhibitory concentration values and the highest zone of inhibition, indicating their marked antibacterial activities. The lowest conc. were observed at 1.56, 6.25μg/mL for inhibition of bacteria by most of the compounds.

CONCLUSION

Novel set of trisubstituted thiazole compounds (AR-17a to AR-27a) have synthesized and characterized successfully. The preliminary screening revealed that these compounds possess promising anti-inflammatory and antibacterial activities. In addition, the objective of the study was achieved with few of the promising structures like AR-17a to AR-27a, which are prove to be potential monotherapy candidates for the treatment of chronic inflammatory diseases and bacterial infections.