Synthesis and evaluation of anticancer, antiphospholipases, antiproteases, and antimetabolic syndrome activities of some 3H-quinazolin-4-one derivatives

Synthesis and Biological Evaluation of Some New 3-Aryl-2-thioxo-2,3-dihydroquinazolin-4(1H)-ones and 3-Aryl-2-(benzylthio)quinazolin-4(3H)-ones as Antioxidants; COX-2, LDHA, α-Glucosidase and α-Amylase Inhibitors; and Anti-Colon Carcinoma and Apoptosis-Inducing Agents

Oxidative stress, COX-2, LDHA and hyperglycemia are interlinked contributing pathways in the etiology, progression and metastasis of colon cancer. Additionally, dysregulated apoptosis in cells with genetic alternations leads to their progression in malignant transformation. Therefore, quinazolinones 3a-3h and 5a-5h were synthesized and evaluated as antioxidants, enzymes inhibitors and cytotoxic agents against LoVo and HCT-116 cells. Moreover, the most active cytotoxic derivatives were evaluated as apoptosis inducers. The results indicated that 3a, 3g and 5a were efficiently scavenged DPPH radicals with lowered IC50 values (mM) ranging from 0.165 ± 0.0057 to 0.191 ± 0.0099, as compared to 0.245 ± 0.0257 by BHT. Derivatives 3h, 5a and 5h were recognized as more potent dual inhibitors than quercetin against α-amylase and α-glucosidase, in addition to 3a, 3c, 3f and 5b-5f against α-amylase. Although none of the compounds demonstrated a higher efficiency than the reference inhibitors against COX-2 and LDHA, 3a and 3g were identified as the most active derivatives. Molecular docking studies were used to elucidate the binding affinities and binding interactions between the inhibitors and their target proteins. Compounds 3a and 3f showed cytotoxic activities, with IC50 values (µM) of 294.32 ± 8.41 and 383.5 ± 8.99 (LoVo), as well as 298.05 ± 13.26 and 323.59 ± 3.00 (HCT-116). The cytotoxicity mechanism of 3a and 3f could be attributed to the modulation of apoptosis regulators (Bax and Bcl-2), the activation of intrinsic and extrinsic apoptosis pathways via the upregulation of initiator caspases-8 and -9 as well as executioner caspase-3, and the arrest of LoVo and HCT-116 cell cycles in the G2/M and G1 phases, respectively. Lastly, the physicochemical, medicinal chemistry and ADMET properties of all compounds were predicted.

Imidazo[1,2-c]quinazolines as a novel and potent scaffold of α-glucosidase inhibitors: design, synthesis, biological evaluations, and in silico studies

α-Glucosidase inhibition is an approved treatment for type 2 diabetes mellitus (T2DM). In an attempt to develop novel anti-α-glucosidase agents, two series of substituted imidazo[1,2-c]quinazolines, namely 6a-c and 11a-o, were synthesized using a simple, straightforward synthetic routes. These compounds were thoroughly characterized by IR, 1H and 13C NMR spectroscopy, as well as mass spectrometry and elemental analysis. Subsequently, the inhibitory activities of these compounds were evaluated against Saccharomyces cerevisiae α-glucosidase. In present study, acarbose was utilized as a positive control. These imidazoquinazolines exhibited excellent to great inhibitory potencies with IC50 values ranging from 12.44 ± 0.38 μM to 308.33 ± 0.06 μM, which were several times more potent than standard drug with IC50 value of 750.0 ± 1.5 μM. Representatively, compound 11j showed remarkable anti-α-glucosidase potency with IC50 = 12.44 ± 0.38 μM, which was 60.3 times more potent than positive control acarbose. To explore the potential inhibition mechanism, further evaluations including kinetic analysis, circular dichroism, fluorescence spectroscopy, and thermodynamic profile were carried out for the most potent compound 11j. Moreover, molecular docking studies and in silico ADME prediction for all imidazoquinazolines 6a-c and 11a-o were performed to reveal their important binding interactions, as well as their physicochemical and drug-likeness properties, respectively.

Synthesis and Biological Evaluation of Octahydroquinazolinones as Phospholipase A2, and Protease Inhibitors: Experimental and Theoretical Exploration

Phospholipase A2 (PLA2) promotes inflammation via lipid mediators and releases arachidonic acid (AA), and these enzymes have been found to be elevated in a variety of diseases, including rheumatoid arthritis, sepsis, and atherosclerosis. The mobilization of AA by PLA2 and subsequent synthesis of prostaglandins are regarded as critical events in inflammation. Inflammatory processes may be treated with drugs that inhibit PLA2, thereby blocking the COX and LOX pathways in the AA cascade. To address this issue, we report herein an efficient method for the synthesis of a series of octahydroquinazolinone compounds (4a-h) in the presence of the catalyst Pd-HPW/SiO₂ and their phospholipase A2, as well as protease inhibitory activities. Among eight compounds, two of them exhibited overwhelming results against PLA2 and protease. By using FT-IR, Raman, NMR, and mass spectroscopy, two novel compounds were thoroughly studied. After carefully examining the SAR of the investigated compounds against these enzymes, it was found that compounds (4a, 4b) containing both electron-donating and electron-withdrawing groups on the phenyl ring exhibited higher activity than compounds with only one of these groups. DFT studies were employed to study the electronic nature and reactivity properties of the molecules by optimizing at the BLYP/cc-pVDZ. Natural bond orbitals helped to study the various electron delocalizations in the molecules, and the frontier molecular orbitals helped with the reactivity and stability parameters. The nature and extent of the expressed biological activity of the molecule were studied using molecular docking with human non-pancreatic secretory phospholipase A2 (hnps-PLA2) (PDB ID: 1DB4) and protease K (PDB ID: 2PWB). The drug-ability of the molecule has been tested using ADMET, and pharmacodynamics data have been extracted. Both the compounds qualify for ADME properties and follow Lipinski's rule of five.

Synthesis and Evaluation of Some New 4H-Pyran Derivatives as Antioxidant, Antibacterial and Anti-HCT-116 Cells of CRC, with Molecular Docking, Antiproliferative, Apoptotic and ADME Investigations

Colorectal cancer oncogenesis is linked to dysbiosis, oxidative stress and overexpression of CDK2. The 4H-pyran scaffold is considered an antitumoral, antibacterial and antioxidant lead as well as a CDK2 inhibitor. Herein, certain 4H-pyran derivatives were evaluated as antibacterial, antioxidant and cytotoxic agents against HCT-116 cells. Derivatives 4g and 4j inhibited all the tested Gram-positive isolates, except for B. cereus (ATCC 14579), with lower IC₅₀ values (µM) than ampicillin. In addition, 4g and 4j demonstrated the strongest DPPH scavenging and reducing potencies, with 4j being more efficient than BHT. In cell viability assays, 4d and 4k suppressed the proliferation of HCT-116 cells, with the lowest IC₅₀ values being 75.1 and 85.88 µM, respectively. The results of molecular docking simulations of 4d and 4k, inhibitory kinase assays against CDK2, along with determination of CDK2 protein concentration and the expression level of CDK2 gene in the lysates of HCT-116 treated cells, suggested that these analogues blocked the proliferation of HCT-116 cells by inhibiting kinase activity and downregulating expression levels of CDK2 protein and gene. Moreover, 4d and 4k were found to induce apoptosis in HCT-116 cells via activation of the caspase-3 gene. Lastly, compounds 4g, 4j, 4d and 4k were predicted to comply with Lipinski’s rule of five, and they are expected to possess excellent physiochemical and pharmacokinetic properties suitable for in vivo bioavailability, as predicted by the SwissADME web tool.

Biological Evaluation, Molecular Docking Analyses, and ADME Profiling of Certain New Quinazolinones as Anti-colorectal Agents

Colorectal carcinogenesis is a complex process, which is linked to dysregulation of human secretory phospholipases A₂ (hsPLA₂-G-IIA, hsPLA₂-G-V, and hsPLA₂-G-X), proteases (cathepsin-B, collagenase, thrombin, elastase, and trypsin), carbohydrate hydrolyzing enzymes (α-amylase and α-glucosidase), and free radical generating enzyme (xanthine oxidoreductase (XOR)). Therefore, some new quinazolinones were synthesized and evaluated as inhibitors against this array of enzymes as well as cytotoxic agents on LoVo and HCT-116 cells of colorectal cancer. Compounds 3g, 10, 8, 3c, and 1c exhibited promising cytotoxic effects with IC₅₀ values ranging from 206.07 to 459.79 μM. Nine compounds showed promising enzymatic inhibitory effects, 3b, 3d, 3f, 5, 1a, and 12 (α-amylase), 8 (thrombin, elastase and trypsin), 10 (hsPLA₂-G-IIA and hsPLA₂-G-V), and 3f (α-glucosidase and XOR). Therefore, the most active inhibitors, were subjected to validated molecular docking studies to identify their affinities and binding modes. The expected physicochemical and pharmacokinetic features of the active candidates, 1a, 1c, 3b, 3c, 3d, 3f, 3g, 5, 8, 10, and 12 were predicted using bioavailability radar charts and boiled-egg graphical representations along with the Lipinski rule of five filter. Collectively, these studies showed the significance of derivatives 1c, 3b, 3c, 3d, 8, 10, and 12 as lead scaffolds for further optimization to develop enzymes inhibitors and anti-colorectal agents.

Green Process for the Synthesis of 3-Amino-2-methyl-quinazolin-4(3H)-one Synthones and Amides Thereof:DNA Photo-Disruptive and Molecular Docking Studies

Eleven 3-amino-2-methyl-quinazolin-4(3H)-ones have been synthesized, in good to excellent yields, via their corresponding benzoxazinones using an efficient tandem microwave-assisted green process. Representative acetamides have been thermally derived from their functional free 3-amino group, whereas for the synthesis of various arylamides, a novel green microwave-assisted protocol has been developed, which involved the attack of hydrazides on benzoxazinones. Eight out of the eleven 3-amino-2-methyl-quinazolin-4(3H)-ones were found photo-active towards plasmid DNA under UVB, and four under UVA irradiation. Amongst all acetamides, only the 6-nitro derivative retained activity both under UVB and UVA irradiation, whereas the 6-bromo-substituted one was active only under UVB. 3-arylamido-6-bromo derivatives exhibited dramatically decreased photo-activity; however, all 3-arylamido-6-nitro compounds developed extraordinary activity, even at concentrations as low as 1μM, which was enhanced compared to their parent 3-amino-2-methyl-6-nitro-quinazolinone. Molecular docking studies were indicative of satisfactory binding to DNA and correlated to the presented photo-activity. Since quinazolinones are known “privileged” pharmacophores for anticancer and antimicrobial activities, the present study gives information on turning “on” and “off” photosensitization on various derivatives which are often used as synthones for drug development, when chromophores and auxochromes are incorporated or being functionalized. Thus, certain compounds may lead to the development of novel photo-chemo or photodynamic therapeutics.

Synthesis, Biological, and Molecular Docking Studies on 4,5,6,7-Tetrahydrobenzo[b]thiophene Derivatives and Their Nanoparticles Targeting Colorectal Cancer

Initiation of colorectal carcinogenesis may be induced by chromosomal instability caused by oxidative stress or indirectly by bacterial infections. Moreover, proliferating tumor cells are characterized by reprogrammed glucose metabolism, which is associated with upregulation of PDK1 and LDHA enzymes. In the present study, some 4,5,6,7-tetrahydrobenzo[b]thiophene derivatives in addition to Fe₃O₄ and Fe₃O₄/SiO₂ nanoparticles (NPs) supported with a new Schiff base were synthesized for biological evaluation as PDK1 and LDHA inhibitors as well as antibacterial, antioxidant, and cytotoxic agents on LoVo and HCT-116 cells of colorectal cancer (CRC). The results showed that compound 1b is the most active as PDK1 and LDHA inhibitor with IC₅₀ values (μg/mL) of 57.10 and 64.10 compared to 25.75 and 15.60, which were produced by the standard inhibitors sodium dichloroacetate and sodium oxamate, respectively. NPs12a,b and compound 1b exhibited the strongest antioxidant properties with IC₅₀ values (μg/mL) of 80.0, 95.0, and 110.0 μg/mL, respectively, compared to 54.0 μg/mL, which was produced by butylated hydroxy toluene. Moreover, NPs12a and carbamate derivative 3b exhibited significant cytotoxic activities with IC₅₀ values (μg/mL) of 57.15 and 81.50 (LoVo cells) and 60.35 and 71.00 (HCT-116 cells). Thus, NPs12a and compound 3b would be considered as promising candidates suitable for further optimization to develop new chemopreventive and chemotherapeutic agents against these types of CRC cell lines. Besides, molecular docking in the colchicine binding site of the tubulin (TUB) domain revealed a good binding affinity of 3b to the protein; in addition, the absorption, distribution, metabolism, and excretion (ADME) analyses showed its desirable drug-likeness and oral bioavailability characteristics.

Design, synthesis, molecular docking, and in vitro α-glucosidase inhibitory activities of novel 3-amino-2,4-diarylbenzo[4,5]imidazo[1,2-a]pyrimidines against yeast and rat α-glucosidase

In an attempt to find novel, potent α-glucosidase inhibitors, a library of poly-substituted 3-amino-2,4-diarylbenzo[4,5]imidazo[1,2-a]pyrimidines 3a–ag have been synthesized through heating a mixture of 2-aminobenzimidazoles 1 and α-azidochalcone 2 under the mild conditions. This efficient, facile protocol has been resulted into the desirable compounds with a wide substrate scope in good to excellent yields. Afterwards, their inhibitory activities against yeast α-glucosidase enzyme were investigated. Showing IC₅₀ values ranging from 16.4 ± 0.36 µM to 297.0 ± 1.2 µM confirmed their excellent potency to inhibit α-glucosidase which encouraged us to perform further studies on α-glucosidase enzymes obtained from rat as a mammal source. Among various synthesized 3-amino-2,4-diarylbenzo[4,5]imidazo[1,2-a]pyrimidines, compound 3k exhibited the highest potency against both Saccharomyces cerevisiae α-glucosidase (IC₅₀ = 16.4 ± 0.36 μM) and rat small intestine α-glucosidase (IC₅₀ = 45.0 ± 8.2 μM). Moreover, the role of amine moiety on the observed activity was studied through substituting with chlorine and hydrogen resulted into a considerable deterioration on the inhibitory activity. Kinetic study and molecular docking study have confirmed the in-vitro results.

Synthesis and Characterization of Some New Quinoxalin-2(1H)one and 2-Methyl-3H-quinazolin-4-one Derivatives Targeting the Onset and Progression of CRC with SRA, Molecular Docking, and ADMET Analyses

The pathogenesis of colorectal cancer is a multifactorial process. Dysbiosis and the overexpression of COX-2 and LDHA are important effectors in the initiation and development of the disease through chromosomal instability, PGE2 biosynthesis, and induction of the Warburg effect, respectively. Herein, we report the in vitro testing of some new quinoxalinone and quinazolinone Schiff’s bases as: antibacterial, COX-2 and LDHA inhibitors, and anticolorectal agents on HCT-116 and LoVo cells. Moreover, molecular docking and SAR analyses were performed to identify the structural features contributing to the biological activities. Among the synthesized molecules, the most active cytotoxic agent, (6d) was also a COX-2 inhibitor. In silico ADMET studies predicted that (6d) would have high Caco-2 permeability, and %HIA (99.58%), with low BBB permeability, zero hepatotoxicity, and zero risk of sudden cardiac arrest, or mutagenicity. Further, (6d) is not a potential P-gp substrate, instead, it is a possible P-gpI and II inhibitor, therefore, it can prevent or reverse the multidrug resistance of the anticancer drugs. Collectively, (6d) can be considered as a promising lead suitable for further optimization to develop anti-CRC agents or glycoproteins inhibitors.

Antioxidant, Cytotoxic, Genotoxic, and DNA-Protective Potential of 2,3-Substituted Quinazolinones: Structure-Activity Relationship Study

The evaluation of antioxidant compounds that counteract the mutagenic effects caused by the direct action of reactive oxygen species on DNA molecule is of considerable interest. Therefore, a series of 2,3-substituted quinazolinone derivatives (Q1-Q8) were investigated by different assays, and the relationship between their biological properties and chemical structure was examined. Genotoxicity and the potential DNA-protective effects of Q1-Q8 were evaluated by comet assay and DNA topology assay. Antioxidant activity was examined by DPPH-radical-scavenging, reducing-power, and total antioxidant status (TAS) assays. The cytotoxic effect of compounds was assessed in human renal epithelial cells (TH-1) and renal carcinoma cells (Caki-1) by MTT assay. Analysis of the structure-activity relationship disclosed significant differences in the activity depending on the substitution pattern. Derivatives Q5-Q8, bearing electron-donating moieties, were the most potent members of this series. Compounds were not genotoxic and considerably decreased the levels of DNA lesions induced by oxidants (H2O2, Fe2+ ions). Furthermore, compounds exhibited higher cytotoxicity in Caki-1 compared to that in TH-1 cells. Substantial antioxidant effect and DNA-protectivity along with the absence of genotoxicity suggested that the studied quinazolinones might represent potential model structures for the development of pharmacologically active agents.

Quinazoline Based HSP90 Inhibitors: Synthesis, Modeling Study and ADME Calculations Towards Breast Cancer Targeting

A new 2-thioquinazolinones series was designed and synthesized as HSP90 inhibitors based on the structure of hit compound VII obtained by virtual screening approach. Their in vitro anti-proliferative activity was evaluated against three human cancer cell lines rich in HSP90 namely; colorectal carcinoma (HCT-116), and cervical carcinoma (Hela), breast carcinoma (MCF-7). Compounds 5a, 5d, 5e and 9h showed a significant broad spectrum anti-proliferative activity against all tested cell lines. They were characterized by potent effect against breast cancer in particular with IC₅₀ of 11.73, 8.56, 7.35 and 9.48 μM, respectively against Doxorubicin (IC₅₀ 4.17 μM). HSP90 ATPase activity inhibition assay were conducted where compound 5d exhibited the best IC₅₀ with 1.58 μM compared to Tanespimycin (IC₅₀ = 2.17 μM). Compounds 5a and 9h showed higher IC₅₀ values of 3.21 and 3.41 μM, respectively. The effects of 5a, 5d and 9h on Her2 (a client proteins of HSP90) and HSP70 were evaluated in MCF-7 cells. All tested compounds were found to reduce Her2 protein expression levels and induce Hsp70 protein expression levels significantly, emphasizing that antibreast cancer effect is a consequence of HSP90 chaperone inhibition. Cell cycle analysis of MCF-7 cells treated with 5d showed cell cycle arrest at G2/M phase 38.89% and pro-apoptotic activity as indicated by annexin V-FITC staining by 22.42%. Molecular docking studies suggested mode of interaction to HSP90 via hydrogen bonding. ADME properties prediction of the active compounds suggested that they could be used as orally absorbed anticancer drug candidates.

From Xanthine Oxidase Inhibition to In Vivo Hypouricemic Effect: An Integrated Overview of In Vitro and In Vivo Studies with Focus on Natural Molecules and Analogues

Hyperuricemia is characterized by elevated uric acid (UA) levels on blood, which can lead to gout, a common pathology. These high UA levels are associated with increased purine ingestion and metabolization and/or its decreased excretion. In this field, xanthine oxidase (XO), by converting hypoxanthine and xanthine to UA, plays an important role in hyperuricemia control. Based on limitations and adverse effects associated with the use of allopurinol and febuxostat, the most known approved drugs with XO inhibitory effect, the search for new molecules with XO activity is growing. However, despite the high number of studies, it was found that the majority of tested products with relevant XO inhibition were left out, and no further pharmacological evaluation was performed. Thus, in the present review, available information published in the past six years concerning isolated molecules with in vitro XO inhibition complemented with cytotoxicity evaluation as well as other relevant studies, including in vivo hypouricemic effect, and pharmacokinetic/pharmacodynamic profile was compiled. Interestingly, the analysis of data collected demonstrated that molecules from natural sources or their mimetics and semisynthetic derivatives constitute the majority of compounds being explored at the moment by means of in vitro and in vivo animal studies. Therefore, several of these molecules can be useful as lead compounds and some of them can even have the potential to be considered in the future clinical candidates for the treatment of hyperuricemia.