Synthesis, In Silico and In Vitro Assessment of New Quinazolinones as Anticancer Agents via Potential AKT Inhibition

Enantioselective synthesis, characterization, molecular docking simulation and ADMET profiling of α-alkylated carbonyl compounds as antimicrobial agents

All living organisms produce only one enantiomer, so we found that all natural compounds are presented in enantiomerically pure form. Asymmetric synthesis is highly spread in medicinal chemistry because enantiomerically pure drugs are highly applicable. This study initially demonstrated the feasibility of a good idea for the asymmetric synthesis of α-alkylated carbonyl compounds with high enantiomeric purity ranging from 91 to 94% using different quinazolinone derivatives. The structure of all compounds was confirmed via elemental analysis and different spectroscopic data and the enantioselectivity was determined via HPLC using silica gel column. The synthesized compounds' mode of action was investigated using molecular docking against the outer membrane protein A (OMPA) and exo-1,3-beta-glucanase, with interpreting their pharmacokinetics aspects. The results of the antimicrobial effectiveness of these compounds revealed that compound 6a has a broad biocidal activity and this in-vitro study was in line with the in-silico results. Overall, the formulated compound 6a can be employed as antimicrobial agent without any toxicity with high bioavailability in medical applications.

Syntheses and Cytotoxicities of Quinazolinone-Based Conjugates

Two novel series of quinazolinone-based hybrids, including quinazolinone-1,3,4-oxadiazoles (10a-l) and quinazolinone-1,3,4-oxadiazole-benzimidazoles (8a-e), were designed and synthesized and their cytotoxic activities against three human cancer cell lines, lung cancer (A549), cervical cancer (HeLa), and breast cancer (MCF-7), were evaluated. The cytotoxic assays revealed that 10i with a lipophilic 4-fluoro-phenyl moiety at the C-2 position of the quinazolinone ring displayed good cytotoxicities against the A549 and MCF-7 cell lines, while 8b-d with the thioether-linked benzimidazole moiety incorporated on the right side of the oxadiazole ring induced comparable stronger activities toward the MCF-7 cell line, relative to the simple two-heterocycle-containing hybrid 10i. These novel quinazolinone-based hybrids could be considered as lead compounds that merit further optimization and development as anti-cancer agents.

Novel 3-phenylquinazolin-2,4(1H,3H)-diones as dual VEGFR-2/c-Met-TK inhibitors: design, synthesis, and biological evaluation

Multitarget anticancer drugs are more superior than single target drugs regarding patient compliance, drug adverse effects, drug-drug interactions, drug resistance as well as pharmaceutical industry economics. Dysregulation of both VEGFR-2 and c-Met tyrosine kinases (TKs) could result in development and progression of different human cancers. Herein, we reported a novel series of 3-phenylquinazolin-2,4(1H,3H)-diones with thiourea moiety as dual VEGFR-2/c-Met TKs. Compared to sorafenib, cabozantinib went behind VEGFR-2 inhibition to target c-Met TK. The dual VEGFR-2/c-Met inhibitory activity of cabozantinib is due to a longer HB domain than that of sorafenib. Based on pharmacophore of cabozantinib analogues, we designed new dual VEGFR-2/c-Met TKs. We synthesized the target compounds via a new single pot three-component reaction. The cytotoxic activity of synthesized compounds was conducted against HCT-116 colorectal cancer cell line. Compounds 3c and 3e exhibited the highest cytotoxic activity against HCT-116 cell line (IC50 1.184 and 3.403 µM, respectively). The in vitro enzyme inhibitory activity was carried out against both VEGFR-2 and c-Met TKs. Compound 3e has the highest inhibitory activity against both VEGFR-2/c-Met (IC50 = 83 and 48 nM, respectively). Docking studies showed that α-oxo moiety in quinazoline ring formed hydrogen bond HB with Met1160 residue in the adenine region of c-Met TK.

Facile One-Pot Three Component Synthesis, Characterization, and Molecular Docking Simulations of Novel α-Aminophosphonate Derivatives Based Pyrazole Moiety as Potential Antimicrobial Agent

An efficient method has been developed for the synthesis of novel α-aminophosphonates (AAP) (3 a-m) through a one-pot three-component reaction of 1,3-disubstituted-1H-pyrazol-5-amine, aromatic aldehydes, and phosphite using lithium perchlorate as catalyst. All newly synthesized compounds were characterized via different spectroscopic techniques. The synthesized compounds' mode of action was investigated using molecular docking against the outer membrane protein A (OMPA) and exo-1,3-β-glucanase, with interpreting their pharmacokinetics aspects. The results of the antimicrobial effectiveness of these compounds revealed a broad spectrum of their biocidal activity and this in-vitro study was in line with the in- silico results. Additionally, it has been demonstrated that these compounds exhibited a minimum inhibitory concentration (MIC) with significant activity at low concentrations (7.5-30.0 mg/mL). Further, the radical scavenging (DPPH* ) activity of the synthesized compounds fluctuated, with compounds 3 h, 3 a, and 3 f showing the highest antioxidant activity. Overall, the formulated compounds can be employed as antimicrobial and antioxidant agents in medical applications.

Novel Para-Aminobenzoic Acid Analogs and Their Potential Therapeutic Applications

A "building block" is a key component that plays a substantial and critical function in the pharmaceutical research and development industry. Given its structural versatility and ability to undergo substitutions at both the amino and carboxyl groups, para-aminobenzoic acid (PABA) is a commonly used building block in pharmaceuticals. Therefore, it is great for the development of a wide range of novel molecules with potential medical applications. Anticancer, anti-Alzheimer's, antibacterial, antiviral, antioxidant, and anti-inflammatory properties have been observed in PABA compounds, suggesting their potential as therapeutic agents in future clinical trials. PABA-based therapeutic chemicals as molecular targets and their usage in biological processes are the primary focus of this review study. PABA's unique features make it a strong candidate for inclusion in a massive chemical database of molecules having drug-like effects. Based on the current literature, further investigation is needed to evaluate the safety and efficacy of PABA derivatives in clinical investigations and better understand the specific mechanism of action revealed by these compounds.

Design, synthesis and molecular docking of novel substituted azepines as inhibitors of PI3K/Akt/TSC2/mTOR signaling pathway in colorectal carcinoma

A series of novel substituted azepines (2-7) was synthesized using both traditional and ultrasonic techniques. The efficiency of the reaction rate and yield was improved by sonication technique. We identified the newly synthesized compounds based on their melting points, elemental analyses, and spectral data. Human cancers are regulated mainly by the phosphatidylinositol 3-kinase/protein kinases B (PI3K/Akt) pathway, and its abnormal activation is linked to carcinogenesis, and angiogenesis. Using in-silico studies, we evaluated the ability of all the novel substituted diazepines and oxazepines to prevent cancer growth and metastasis by targeting the PI3K/Akt signaling pathway. Based on our findings, compounds 4a and 7a were chosen for in-vitro testing as they ranked via molecular docking the highest binding energies of -10.9, -10.3, -10.6, and -10.4 kcal/mol respectively. Compounds 4a and 7a displayed significant cytotoxicity on Caco-2 colorectal cancer cells with IC₅₀ values of 8.445 ± 2.26 and 33.04 ± 2.06 μM, respectively. Additionally, they considerably suppressed the PI3K/Akt proteins and generated reactive oxygen species (ROS), which increased p53 and Bax, decreased Bcl-₂ levels, and arrested the cell cycle at sub-G0/G1 phase. We also observed a remarkable overexpression of the Tuberous Sclerosis Complex 2 (TSC2) gene, an inhibitor of the mammalian target of rapamycin (mTOR). These results showed that compounds 4a and 7a obeyed Lipinski's rule of five and might be potential cancer treatment scaffolds by preventing metastasis and proliferation via blocking the PI3K/Akt/TSC2/m-TOR signaling pathway. This supports our hypothesis that diazepine 4a and oxazepine 7a are promising drug candidates for colorectal cancer.

Quinazolinones, the Winning Horse in Drug Discovery

Quinazolines are nitrogen-containing heterocycles that consist of a benzene ring fused with a pyrimidine ring. Quinazolinones, oxidized quinazolines, are promising compounds with a wide range of biological activities. In the pharmaceutical field, quinazolinones are the building blocks of more than 150 naturally occurring alkaloids isolated from different plants, microorganisms, and animals. Scientists give a continuous interest in this moiety due to their stability and relatively easy methods for preparation. Their lipophilicity is another reason for this interest as it helps quinazolinones in penetration through the blood-brain barrier which makes them suitable for targeting different central nervous system diseases. Various modifications to the substitutions around the quinazolinone system changed their biological activity significantly due to changes in their physicochemical properties. Structure-activity relationship (SAR) studies of quinazolinone revealed that positions 2, 6, and 8 of the ring systems are significant for different pharmacological activities. In addition, it has been suggested that the addition of different heterocyclic moieties at position 3 could increase activity. In this review, we will highlight the chemical properties of quinazolinones, including their chemical reactions and different methods for their preparation. Moreover, we will try to modify some of the old SAR studies according to their updated biological activities in the last twelve years.

Structural insights into conformational stability and binding of thiazolo-[2,3-b] quinazolinone derivatives with EGFR-TKD and in-vitro study

Heterocyclic molecules are well-known drugs against various diseases including cancer. Many tyrosine kinase inhibitors including erlotinib, osimertinib, and sunitinib were developed and approved but caused adverse effects among treated patients. Which prevents them from being used as cancer therapeutics. In this study, we strategically developed heterocyclic thiazolo-[2,3-b]quinazolinone derivatives by an organic synthesis approach. These synthesized molecules were assessed against the epidermal growth factor receptor tyrosine kinase domain (EGFR-TKD) by in silico methods. Molecular docking simulations unravel derivative 17 showed better binding energy scores and followed Absorption, Distribution, Metabolism, Excretion, and Toxicity (ADMET) properties. The binding affinity displayed by synthetic congener and reference molecule erlotinib was found to be -8.26 ± 0.0033 kcal/mol and -7.54 ± 0.1411 kcal/mol with the kinase domain. Further, molecular dynamic simulations were conducted thrice to validate the molecular docking study and achieved significant results. Both synthetic derivative and reference molecule attained stability in the active site of the TKD. The synthetic congener and erlotinib showed free energy binding (ΔGbind) -102.975 ± 3.714 kJ/mol and -130.378 ± 0.355 kJ/mol computed by Molecular Mechanics Poison Boltzmann Surface Area (MM-PBSA) method. In addition, the motions of each sampled system including the Apo complex were determined by the principal component analysis and Gibbs energy landscape analysis. The in-vitro apoptosis study was performed using MCF-7 and H-1299 cancer cell lines. However, thiazolo-[2,3-]-quinazoline derivative 17 showed fair anti-proliferative activity against MCF-7 and H-1299. Further, the in-vivo study is necessary to determine the effectivity of the potent anti-proliferative, non-toxic molecule against TKD.

Newly Synthesized Pyrazolinone Chalcones as Anticancer Agents via Inhibiting the PI3K/Akt/ERK1/2 Signaling Pathway

A series of novel pyrazolinone chalcones 3-9 have been synthesized through the condensation of azo pyrazolinone derivatives with various aromatic aldehydes. Spectroscopic techniques and elemental analysis have both corroborated this. Furthermore, all compounds were screened in silico for their ability to inhibit cancer proliferation and metastasis by targeting the PI3K/Akt signaling pathway. This inhibitory pathway might be an efficient approach for the death of cancer cells, angiogenesis, and metastasis prevention. Our results indicated that only compound 6b was the top-ranked. It demonstrated the highest binding energies of -11.1 and -10.7 kcal/mol against the target proteins PI3K and Akt, respectively; thus, it was chosen for in vitro studies. Compound 6b exhibited the most effective cytotoxic impact against the Caco cell line with IC50 of 23.34 ± 0.14 μM. Furthermore, it showed significant inhibition of PI3K/Akt proteins and oxidative stress, leading to elevated Bax and p53 expression, reduced Bcl-2 expression, and triggered cell cycle arrest at the sub-G0/G1 phase. Additionally, it showed significant downregulation of the Raf-1 gene, leading to ERK1/2 protein inhibition. These findings demonstrate that compound 6b obeyed Lipinski's rule of five and might be used as a favored scaffold for cancer treatment by inhibiting proliferation and metastasis via inhibition of the PI3K/Akt and Raf-1/ERK1/2 signaling pathways.

Access to Phosphine-Containing Quinazolinones Enabled by Photo-Induced Radical Phosphorylation/Cyclization of Unactivated Alkenes

A mild and facile photo-induced cascade radical addition/cyclization of unactivated alkenes has been reported, through which a variety of biologically valuable phosphine-containing quinazolinones could be obtained in moderate to good yields. The protocol was characterized by mild conditions, broad substrate scope, and high atomic economy.

In silico study to identify novel potential thiadiazole-based molecules as anti-Covid-19 candidates by hierarchical virtual screening and molecular dynamics simulations

In the present study, a new category of 1,3,4-thiadiazoles was developed by submitting methyl 2-(4-hydroxy-3-methoxybenzylidene) hydrazine-1-carbodithioate to react with the appropriate hydrazonoyl halides in presence of few drops of diisopropyl ethyl amine. The chemical structures of the newly synthesized derivatives were inferred by means of their micro-analytical and spectral data. Utilizing combined molecular docking and molecular dynamics techniques, the binding affinities and features of the synthesized compounds were evaluated against four SARS-CoV-2 target enzymes, namely, main protease (M^pro), papain-like protease (PL^pro), RNA-dependent RNA polymerase (RdRp), and receptor-binding domain (RBD) of the spike protein. Compound 7 demonstrated promising binding affinities with the target enzymes M^pro, PL^pro, RdRp, and RBD with docking scores of −11.4, −9.4, −8.2, and −6.8 kcal/mol, respectively. In addition, compound 7 exhibited MM-GBSA//100 ns MD docking score of −35.9 kcal/mol against M^pro. Structural and energetic analyses revealed the stability of the 7-M^pro complex over 100 ns MD simulations. In addition, compound 7 obeyed Lipinski’s rule of five, as it has acceptable absorption, distribution, and oral bioavailability inside the body. Therefore, compound 7 is considered as a promising starting point for designing potential therapeutic agents against Covid-19.

Preparation of quinazolinones using biosynthesized silver nanoparticles

A silver nanocatalyst has been used as an effective catalyst for the preparation of quinazolinones under reflux conditions in ethanol. The catalyst was characterized by UV-VIS, FT-IR, XRD, SEM and EDS. Amongst the many benefits of this method are atom economy, reusability of the catalyst, low catalyst loading, applicability to a wide range of substrates, high yields of products, environmental friendliness and easy separation of products. Silver nanoparticles (Ag NPs) were prepared using Echium amoenum extract. The structures of the prepared quinazolinones were fully characterized by 1H and 13C NMR, FT-IR spectra and elemental analysis.

Synthesis, Molecular Docking Analysis and in Vitro Biological Evaluation of Some New Heterocyclic Scaffolds-Based Indole Moiety as Possible Antimicrobial Agents

In the present study, a general approach for the synthesis of 1-(1H-indol-3-yl)-3,3-dimercaptoprop-2-en-1-one (1) and 5-(1H-indol-3-yl)-3H-1,2-dithiole-3-thione (2) was performed. They are currently used as efficient precursors for the synthesis of some new compounds bearing five- and/or six-membered heterocyclic moieties, e.g., chromenol (3, 4), 3,4-dihydroquinoline (7, 8) and thiopyran (10, 12)-based indole core. In addition, molecular docking studies were achieved, which showed that all the newly synthesized compounds are interacting with the active site region of the target enzymes, the targets UDP-N-acetylmuramatel-alanine ligase (MurC), and human lanosterol14α-demethylase, through hydrogen bonds and pi-stacked interactions. Among these docked ligand molecules, the compound (9) was found to have the minimum binding energy (−11.5 and −8.5 Kcal/mol) as compared to the standard drug ampicillin (−8.0 and −8.1 Kcal/mol) against the target enzymes UDP-N-acetylmuramatel-alanine ligase (MurC), and Human lanosterol14α-demethylase, respectively. Subsequently, all new synthesized analogues were screened for their antibacterial activities against Gram-positive (Bacillus subtilis), and Gram-negative bacteria (Escherichia coli), as well as for antifungal activities against Candida albicans and Aspergillus flavus. The obtained data suggest that the compounds exhibited good to excellent activity against bacterial and fungi strains. The compound (E)-2-(6-(1H-indole-3-carbonyl)-5-thioxotetrahydrothieno [3,2-b]furan-2(3H)-ylidene)-3-(1H-indol-3-yl)-3-oxopropanedithioic acid (9) showed a high binding affinity as well as an excellent biological activity. Therefore, it could serve as the lead for further optimization and to arrive at potential antimicrobial agent.

Synthesis, characterization, in silico molecular docking, and antibacterial activities of some new nitrogen-heterocyclic analogues based on a p-phenolic unit

Compounds 6a and 6b (with pyrimidine moiety, amide linkage, and phenolic substrate) might be potent bacterial flavohemoglobin (flavoHB) inhibitors and they could set a promising starting point for future design of antibacterial agents.

Synthesis, Identification, Computer-Aided Docking Studies, and ADMET Prediction of Novel Benzimidazo-1,2,3-triazole Based Molecules as Potential Antimicrobial Agents

2-azido-1H-benzo[d]imidazole derivatives 1a,b were reacted with a β-ketoester such as acetylacetone in the presence of sodium ethoxide to obtain the desired molecules 2a,b. The latter acted as a key molecule for the synthesis of new carbazone derivatives 4a,b that were submitted to react with 2-oxo-N-phenyl-2-(phenylamino)acetohydrazonoyl chloride to obtain the target thiadiazole derivatives 6a,b. The structures of the newly synthesized compounds were inferred from correct spectral and microanalytical data. Moreover, the newly prepared compounds were subjected to molecular docking studies with DNA gyrase B and exhibited binding energy that extended from -9.8 to -6.4 kcal/mol, which confirmed their excellent potency. The compounds 6a,b were found to be with the minimum binding energy (-9.7 and -9.8 kcal/mol) as compared to the standard drug ciprofloxacin (-7.4 kcal/mol) against the target enzyme DNA gyrase B. In addition, the newly synthesized compounds were also examined and screened for their in vitro antimicrobial activity against pathogenic microorganisms Staphylococcus aureus, E. coli, Pseudomonas aeruginosa, Aspergillus niger, and Candida albicans. Among the newly synthesized molecules, significant antimicrobial activity against all the tested microorganisms was obtained for the compounds 6a,b. The in silico and in vitro findings showed that compounds 6a,b were the most active against bacterial strains, and could serve as potential antimicrobial agents.

New Amino Acid Schiff Bases as Anticancer Agents via Potential Mitochondrial Complex I-Associated Hexokinase Inhibition and Targeting AMP-Protein Kinases/mTOR Signaling Pathway

Two series of novel amino acid Schiff base ligands containing heterocyclic moieties, such as quinazolinone 3–11 and indole 12–20 were successfully synthesized and confirmed by spectroscopic techniques and elemental analysis. Furthermore, all compounds were investigated in silico for their ability to inhibit mitochondrial NADH: ubiquinone oxidoreductase (complex I) by targeting the AMPK/mTOR signaling pathway and inhibiting hexokinase, a key glycolytic enzyme to prevent the Warburg effect in cancer cells. This inhibitory pathway may be an effective strategy to cause cancer cell death due to an insufficient amount of ATP. Our results revealed that, out of 18 compounds, two (11 and 20) were top-ranked as they exhibited the highest binding energies of −8.8, −13.0, −7.9, and −10.0 kcal/mol in the docking analysis, so they were then selected for in vitro assessment. Compound 11 promoted the best cytotoxic effect on MCF-7 with IC₅₀ = 64.05 ± 0.14 μg/mL (0.135 mM) while compound 20 exhibited the best cytotoxic effect on MDA-231 with IC₅₀ = 46.29 ± 0.09 μg/mL (0.166 mM) Compounds 11 and 20 showed significant activation of AMPK protein and oxidative stress, which led to elevated expression of p53 and Bax, reduced Bcl-2 expression, and caused cell cycle arrest at the sub-G₀/G₁ phase. Moreover, compounds 11 and 20 showed significant inhibition of the mTOR protein, which led to the activation of aerobic glycolysis for survival. This alternative pathway was also blocked as compounds 11 and 20 showed significant inhibitory effects on the hexokinase enzyme. These findings demonstrate that compounds 11 and 20 obeyed Lipinski’s rule of five and could be used as privileged scaffolds for cancer therapy via their potential inhibition of mitochondrial complex I-associated hexokinase.

Eco-Friendly Synthesis, Biological Evaluation, and In Silico Molecular Docking Approach of Some New Quinoline Derivatives as Potential Antioxidant and Antibacterial Agents

A new series of quinoline derivatives 5–12 were efficiently synthesized via one-pot multicomponent reaction (MCR) of resorcinol, aromatic aldehydes, β-ketoesters, and aliphatic/aromatic amines under solvent-free conditions. All products were obtained in excellent yields, pure at low-cost processing, and short time. The structures of all compounds were characterized by means of spectral and elemental analyses. In addition, all the synthesized compounds 5–12 were in vitro screened for their antioxidant and antibacterial activity. Moreover, in silico molecular docking studies of the new quinoline derivatives with the target enzymes, human NAD (P)H dehydrogenase (quinone 1) and DNA gyrase, were achieved to endorse their binding affinities and to understand ligand–enzyme possible intermolecular interactions. Compound 9 displayed promising antioxidant and antibacterial activity, as well as it was found to have the highest negative binding energy of -9.1 and -9.3 kcal/mol for human NAD (P)H dehydrogenase (quinone 1) and DNA gyrase, respectively. Further, it complied with the Lipinski’s rule of five, Veber, and Ghose. Therefore, the quinoline analogue 9 could be promising chemical scaffold for the development of future drug candidates as antioxidant and antibacterial agents.

6-Nitro-7-tosylquinazolin-4(3H)-one

Sulfones are important building blocks in the construction of biologically active molecules or functional materials. The sulfonyl functional group in sulfones is so versatile that it can act as either a nucleophile, an electrophile, or a radical in different organic reactions. Recently, quinazoline sulfones have been used to build asymmetrical ether derivatives as inhibitors of signaling pathways governed by tyrosine kinases and the epidermal growth factor-receptor. In this paper, we report a facile synthesis of a novel quinazoline sulfone, 6-nitro-7-tosylquinazolin-4(3H)-one (III), using the modified protocol from 7-chloro-6-nitroquinazolin-4(3H)-one (I) and sodium p-toluenesulfinate (II). The structure of the title compound III was determined using mass-spectrometry, FT-IR, 1H-NMR, 13C-NMR, DEPT, HSQC (Heteronuclear single quantum coherence), HMBC (Heteronuclear Multiple Bond Correlation Spectroscopy) spectroscopies, and PXRD analysis.