Synthesis, anti-inflammatory, analgesic, COX-1/2 inhibitory activities and molecular docking studies of substituted 2-mercapto-4(3H)-quinazolinones

A new series of 2-substituted mercapto-4(3H)-quinazolinone 1-26 were synthesized and assessed for in vivo anti-inflammatory and analgesic activities and in vitro inhibition of cyclooxygenase COX-1/COX-2. A new series of 2-substituted mercapto-4(3H)-quinazolinone 1-26 were synthesized and assessed for in vivo anti-inflammatory and analgesic activities. The potent anti-inflammatory compounds were subjected to in vitro cyclooxygenase COX-1/COX-2 inhibition assays. Compounds 1, 3, 5, 11, 12, 13, 15, 17, and 25 exhibited potent anti-inflammatory effects, with half-maximal effective dose (ED50) values of 65.7-102.4 mg/kg, (0.16-0.36 mmol/kg), and strong analgesic activities, with ED50 values of 33.3-104.6 mg/kg, (0.07-0.34 mmol/kg). These values were compared with those of diclofenac sodium [ED50 values: 112.2 and 100.4 mg/kg, (0.35 and 0.31 mmol/kg)], and celecoxib [ED50 values: 84.3 and 71.6 mg/kg (0.22 and 0.19 mmol/kg)], respectively as reference drugs. Compounds 1, 11, 12, 13, 15, 17, and 25 exhibited effective COX-2 inhibitory activity, with half-maximal inhibitor concentration (IC50) values of 0.70-2.0 μM and selectivity index (SI) values of more than 50-142.9 compared with celecoxib as reference drugs (IC50 = 0.30 μM and COX-2 SI: >333). Potent COX-2 inhibitors, i.e., compounds 15, 11, and 17 were docked into the binding site pockets of COX-1 and COX-2. These compounds exhibited strong interactions at the COX-2 binding site and poor interactions at COX-1 active site pocket.

Design, synthesis, and anti-proliferative evaluation of new quinazolin-4(3H)-ones as potential VEGFR-2 inhibitors

Inhibiting VEGFR-2 has been set up as a therapeutic strategy for treatment of cancer. Thus, nineteen new quinazoline-4(3H)-one derivatives were designed and synthesized. Preliminary cytotoxicity studies of the synthesized compounds were evaluated against three human cancer cell lines (HepG-2, MCF-7 and HCT-116) using MTT assay method. Doxorubicin and sorafenib were used as positive controls. Five compounds were found to have promising cytotoxic activities against all cell lines. Compound 16_f, containing a 2-chloro-5-nitrophenyl group, has emerged as the most active member. It was approximately 4.39-, 5.73- and 1.96-fold more active than doxorubicin and 3.88-, 5.59- and 1.84-fold more active than sorafenib against HepG2, HCT-116 and MCF-7 cells, respectively. The most active cytotoxic agents were further evaluated in vitro for their VEGFR-2 inhibitory activities. The results of in vitro VEGFR-2 inhibition were consistent with that of the cytotoxicity data. Molecular docking of these compounds into the kinase domain, moreover, supported the results.

Synthesis, antitumor activity and molecular docking study of some novel 3-benzyl-4(3H)quinazolinone analogues

A novel series of 3-benzyl-substituted-4(3H)-quinazolinones were designed, synthesized and evaluated for their in vitro antitumor activity. The results of this study demonstrated that 2-(3-benzyl-6-methyl-4-oxo-3,4-dihydroquinazolin-2-ylthio)-N-(3,4,5-trimethoxyphenyl)acetamide, 2-(3-benzyl-6,7-dimethoxy-4-oxo-3,4-dihydroquinazolin-2-ylthio)-N-(3,4,5-trimethoxyphenyl)acetamide and 3-(3-benzyl-6-methyl-4-oxo-3,4-dihydroquinazolin-2-ylthio)-N-(3,4,5-trimethoxyphenyl)-propanamide have shown amazing broad spectrum antitumor activity with mean GI(50) (10.47, 7.24 and 14.12 µM. respectively), and are nearly 1.5-3.0-fold more potent compared with the positive control 5-FU with mean GI50, 22.60 µM. On the other hand, compounds 6 and 10 yielded selective activities toward CNS, renal and breast cancer cell lines, whereas compound 9 showed selective activities towards leukemia cell lines. Molecular docking methodology was performed for compounds 7 and 8 into ATP binding site of EGFR-TK which showed similar binding mode to erlotinib, while compound 11 into ATP binding site of B-RAF kinase inhibited the growth of melanoma cell lines through inhibition of B-RAF kinase, similar to PLX4032.

Discovery and antiproliferative evaluation of new quinoxalines as potential DNA intercalators and topoisomerase II inhibitors

In continuation of our previous work on the design and synthesis of topoisomerase II (Topo II) inhibitors and DNA intercalators, a new series of quinoxaline derivatives were designed and synthesized. The synthesized compounds were evaluated for their cytotoxic activities against a panel of three cancer cell lines (Hep G-2, Hep-2, and Caco-2). Compounds 18b, 19b, 23, 25b, and 26 showed strong potencies against all tested cell lines with IC₅₀ values ranging from 0.26 ± 0.1 to 2.91 ± 0.1 µM, comparable with those of doxorubicin (IC₅₀ values ranging from 0.65 ± 0.1 to 0.81 ± 0.1 µM). The most active compounds were further evaluated for their Topo II inhibitory activities and DNA intercalating affinities. Compounds 19b and 19c exhibited high activities against Topo II (IC₅₀ = 0.97 ± 0.1 and 1.10 ± 0.1 µM, respectively) and bound the DNA at concentrations of 43.51 ± 2.0 and 49.11 ± 1.8 µM, respectively, whereas compound 28b exhibited a significant affinity to bind the DNA with an IC₅₀ value of 37.06 ± 1.8 µM. Moreover, apoptosis and cell-cycle tests of the most promising compound 19b were carried out. It was found that 19b can significantly induce apoptosis in Hep G-2 cells. It has revealed cell-cycle arrest at the G2/M phase. Moreover, compound 19b downregulated the Bcl-2 levels, indicating its potential to enhance apoptosis. Furthermore, molecular docking studies were carried out against the DNA-Topo II complex to examine the binding patterns of the synthesized compounds.

Synthesis, antitumor and antimicrobial activity of some new 6-methyl-3-phenyl-4(3H)-quinazolinone analogues: in silico studies

Some new derivatives of substituted-4(3H)-quinazolinones were synthesized and evaluated for their in vitro antitumor and antimicrobial activities. The results of this study demonstrated that compound 5 yielded selective activities toward NSC Lung Cancer EKVX cell line, Colon Cancer HCT-15 cell line and Breast Cancer MDA-MB-231/ATCC cell line, while NSC Lung Cancer EKVX cell line and CNS Cancer SF-295 cell line were sensitive to compound 8. Additionally, compounds 12 and 13 showed moderate effectiveness toward numerous cell lines belonging to different tumor subpanels. On the other hand, the results of antimicrobial screening revealed that compounds 1, 9 and 14 are the most active against Staphylococcus aureus ATCC 29213 with minimum inhibitory concentration (MIC) of 16, 32 and 32 μg/mL respectively, while compound 14 possessed antimicrobial activities against all tested strains with the lowest MIC compared with other tested compounds. In silico study, ADME-Tox prediction and molecular docking methodology were used to study the antitumor activity and to identify the structural features required for antitumor activity.

Synthesis and potential antitumor activity of 7-(4-substituted piperazin-1-yl)-4-oxoquinolines based on ciprofloxacin and norfloxacin scaffolds: in silico studies

The potential antitumor activities of a series of 7-(4-substituted piperazin-1-yl)fluoroquinolone derivatives (1-14a,b) using ciprofloxacin and norfloxacin as scaffolds are described. These compounds exhibit potent and broad spectrum antitumor activities using 60 human cell lines in addition to the inherent antibacterial activity. Compounds 1a, 2a, 3b, 6b and 7a were found to be the most potent, while 2b, 5b, and 6a were found to have an average activity. The results of this study demonstrated that compounds 1a, 2a, 3b, 6b and 7a (mean GI50; 2.63-3.09 µM) are nearly 7-fold more potent compared with the positive control 5-fluorouracil (mean GI50; 22.60 µM). More interestingly, compounds 1a, 2a, 3b, 6b and 7a have an almost antitumor activity similar to gefitinib (mean GI50; 3.24 µM) and are nearly 2-fold more potent compared to erlotinib (mean GI50; 7.29 µM). In silico study and ADME-Tox prediction methodology were used to study the antitumor activity of the most active compounds and to identify the structural features required for antitumor activity.

Inhibition of carbonic anhydrase isoforms I, II, IV, VII and XII with carboxylates and sulfonamides incorporating phthalimide/phthalic anhydride scaffolds

We report a panel of carboxylates and sulfonamides incorporating phthalic anhydride and phthalimide moieties in their structure and their interaction with the metalloenzyme carbonic anhydrase (CA, EC 4.2.1.1). They were synthesized from substituted anthranilic acids and trimellitic anhydride chloride, followed by reaction with primary amines and were tested for the inhibition of five physiologically relevant CA isoforms, the human (h) hCA I, II, IV, VII and XII, some of which are involved in serious pathologies (CA II, IV and XII in glaucoma; CA VII in epilepsy; CA XII in some solid tumors). The carboxylic acids were generally poor inhibitors of isoforms hCA I, II and IV but were highly effective, low nanomolar inhibitors of hCA VII and XII. The sulfonamides inhibited all isoforms significantly, and some of them were sub-nanomolar hCA VII inhibitors, although their isoform selectivity was lower compared to the carboxylates. This study proves that carboxylic acids incorporating a phthalic anhydride/phthalimide based scaffold may lead to isoform-selective inhibitors by applying the tail approach, mostly used up until now for obtaining sulfonamide, sulfamide and sulfamate CA inhibitors.

Design, synthesis, molecular docking, anticancer evaluations, and in silico pharmacokinetic studies of novel 5-[(4-chloro/2,4-dichloro)benzylidene]thiazolidine-2,4-dione derivatives as VEGFR-2 inhibitors

The anticancer activity of novel thiazolidine-2,4-diones was evaluated against HepG2, HCT-116, and MCF-7 cells. MCF-7 was the most sensitive cell line to the cytotoxicity of the new derivatives. In particular, compounds 18, 12, 17, and 16 were found to be the most potent derivatives over all the tested compounds against the cancer cell lines HepG2, HCT116, and MCF-7, with IC₅₀  = 9.16 ± 0.9, 8.98 ± 0.7, 5.49 ± 0.5 µM; 9.19 ± 0.5, 8.40 ± 0.7, 6.10 ± 0.4 µM; 10.78 ± 1.2, 8.87 ± 1.5, 7.08 ± 1.6 µM; and 10.87 ± 0.8, 9.05 ± 0.7, 7.32 ± 0.4 µM, respectively. Compounds 18 and 12 have nearly the same activities as sorafenib (IC₅₀  = 9.18 ± 0.6, 5.47 ± 0.3, and 7.26 ± 0.3 µM, respectively), against HepG2 cells, but slightly lower activity against HCT116 cells and slightly higher activity against the MCF-7 cancer cell line. Also, these compounds displayed lower activities than doxorubicin against HepG2 and HCT-116 cells but higher activity against MCF-7 cells (IC₅₀  = 7.94 ± 0.6, 8.07 ± 0.8, and 6.75 ± 0.4 µM, respectively). In contrast, compounds 17 and 16 exhibited lower activities than sorafenib against HepG2 and HCT116 cells, but nearly equipotent activity against the MCF-7 cancer cell line. Also, these compounds displayed lower activities than doxorubicin against the three cell lines. All the synthesized derivatives 7-18 were evaluated for their inhibitory activities against VEGFR-2. The tested compounds displayed high to medium inhibitory activity, with IC₅₀ values ranging from 0.17 ± 0.02 to 0.27 ± 0.03 µM. Compounds 18, 12, 17, and 16 potently inhibited VEGFR-2 at IC₅₀ values of 0.17 ± 0.02, 0.17 ± 0.02, 0.18 ± 0.02, and 0.18 ± 0.02 µM, respectively, which are nearly more than half of that of the IC₅₀ value for sorafenib (0.10 ± 0.02 µM).

Development of novel benzofuran-isatin conjugates as potential antiproliferative agents with apoptosis inducing mechanism in Colon cancer

In the current work, a new set of carbohydrazide linked benzofuran-isatin conjugates (5a-e and 7a-i) was designed and synthesised. The anticancer activity for compounds (5b-d, 7a, 7b, 7d and 7g) was measured against NCI-55 human cancer cell lines. Compound 5d was the most efficient, and thus subjected to the five-dose screen where it showed excellent broad activity against almost all tested cancer subpanels. Furthermore, all conjugates (5a-e and 7a-i) showed a good anti-proliferative activity towards colorectal cancer SW-620 and HT-29 cell lines, with an excellent inhibitory effect for compounds 5a and 5d (IC50 = 8.7 and 9.4 µM (5a), and 6.5 and 9.8 µM for (5d), respectively). Both compounds displayed selective cytotoxicity with good safety profile. In addition, both compounds provoked apoptosis in a dose dependent manner in SW-620 cells. Also, they significantly inhibited the anti-apoptotic Bcl2 protein expression and increased the cleaved PARP level that resulted in SW-620 cells apoptosis.

Development of 2-oindolin-3-ylidene-indole-3-carbohydrazide derivatives as novel apoptotic and anti-proliferative agents towards colorectal cancer cells

Mitochondrial anti-apoptotic Bcl2 and BclxL proteins, are overexpressed in multiple tumour types, and has been involved in the progression and survival of malignant cells. Therefore, inhibition of such proteins has become a validated and attractive target for anticancer drug discovery. In this manner, the present studies developed a series of novel isatin-indole conjugates (7a-j and 9a-e) as potential anticancer Bcl2 and BclxL inhibitors. The progression of the two examined colorectal cancer cell lines was significantly inhibited by all of the prepared compounds with IC₅₀ ranges132-611 nM compared to IC₅₀ = 4.6 µM for 5FU, against HT-29 and IC₅₀ ranges 37-468 nM compared to IC₅₀ = 1.5 µM for 5FU, against SW-620. Thereafter, compounds 7c and 7g were selected for further investigations. Interestingly, both compounds exhibited selective cytotoxicity against both cell lines with high safety to normal fibroblast (HFF-1). In addition, both compounds 7c and 7g induced apoptosis and inhibited Bcl2 and BclxL expression in a dose-dependent manner. Collectively, the high potency and selective cytotoxicity suggested that conjugates 7c and 7g could be a starting point for further optimisation to develop novel pro-apoptotic and antitumor agents towards colon cancer.

Some novel anticonvulsant agents derived from phthalazinedione

A series of phthalazinedione bearing substituted oxadiazole moiety derivatives X(1-7) were synthesized in good yield and evaluated for their possible anticonvulsant activity. The structures of the synthesized compounds were confirmed on the basis of their spectral data and elemental analysis. Their anticonvulsant activities were evaluated by the maximal electroshock induced seizure (MES) and subcutaneous pentylenetetrazole (PTZ) tests. All the tested compounds showed considerable anticonvulsant activities in at least one of the anticonvulsant tests. Moreover, some of the tested compounds exhibited moderate anticonvulsant activities in both MES and PTZ tests. From these results,[3-)2-Alkoxycarbonylmethylthioxadiozol-5-yl)methyl -6-Iodophthalazine - 1,4- (2H,3H)-1,4-dion] (X1-7) derivatives could be recommended as novel structures of broad spectrum anticonvulsants.

Discovery of novel triazolophthalazine derivatives as DNA intercalators and topoisomerase II inhibitors

A new series of triazolophthalazine derivatives was designed and synthesized as topoisomerase II (Topo II) inhibitors and DNA intercalators. The synthesized derivatives were evaluated in vitro for their cytotoxic activities against three human cancer cell lines: HepG2, MCF-7, and HCT-116 cells. Compound IX_b was the most potent counterpart with IC₅₀ values of 5.39 ± 0.4, 3.81 ± 0.2, and 4.38 ± 0.3 µM, as it was about 1.47, 1.77, and 1.19 times more active than doxorubicin (IC₅₀  = 7.94 ± 0.6, 6.75 ± 0.4, and 5.23 ± 0.3 µM) against HepG2, MCF-7, and HCT-116 cells, respectively. Additionally, the binding affinity of the synthesized compounds toward the DNA molecule was assessed using the DNA/methyl green assay. Compound IX_b showed an excellent DNA binding affinity with an IC₅₀ value of 27.16 ± 1.2 µM, which was better than that of the reference drug doxorubicin (IC₅₀  = 31.02 ± 1.80 µM). Moreover, compound IX_b was the most potent member among the tested compounds when investigated for their Topo II inhibitory activity. Furthermore, compound IX_b induced apoptosis in HepG2 cells and arrested the cell cycle at the G2/M phase. Additionally, compound IX_b showed Topo II poisoning effects at 2.5 μM and Topo II catalytic inhibitory effects at 5 and 10 μM. Finally, molecular docking studies were carried out against the DNA-Topo II complex and DNA, to investigate the binding patterns of the designed compounds.

1-Benzyl-5-bromo-3-hydrazonoindolin-2-ones as Novel Anticancer Agents: Synthesis, Biological Evaluation and Molecular Modeling Insights

Human health is experiencing several obstacles in the modern medical era, particularly cancer. As a result, the cancer therapeutic arsenal should be continually expanded with innovative small molecules that preferentially target tumour cells. In this study, we describe the development of two small molecule series (7a–d and 12a–e) based on the 1-benzyl-5-bromoindolin-2-one scaffold that connected through a hydrazone linker to a 4-arylthiazole (7a–d) or 4-methyl-5-(aryldiazenyl)thiazole (12a–e) moiety. The anticancer activity of all the reported indolin-2-one derivatives was assessed against breast (MCF-7) and lung (A-549) cancer cell lines. The 4-arylthiazole-bearing derivatives 7c and 7d revealed the best anticancer activity toward MCF-7 cells (IC50 = 7.17 ± 0.94 and 2.93 ± 0.47, respectively). Furthermore, the VEGFR-2 inhibitory activity for 7c and 7d was evaluated. Both molecules disclosed good inhibitory activity, and their IC50 values were equal to 0.728 µM and 0.503 µM, respectively. Additionally, the impacts of 7d on the cell cycle phases as well as on the levels of different apoptotic markers (caspase-3, caspase-9, Bax, and Bcl-2) were assessed. Molecular docking and dynamic simulations are carried out to explore the binding mode of 7d within the VEGFR-2 active site.

New immunomodulatory anticancer quinazolinone-based thalidomide analogs: design, synthesis and biological evaluation

Aim: The current work is an extension to our previous work for the development of new thalidomide analogs.Materials & methods: Quinazolinone-based molecules carrying a glutarimide moiety have been designed, synthesized and biologically evaluated for immunomodulatory and anticancer activity.Results: Compounds 7d and 12 showed considerable immunomodulatory properties in comparison to thalidomide. 7d and 12 significantly reduced TNF-α levels in HepG-2 cells from 162.5 to 57.4 pg/ml and 49.2 pg/ml, respectively, compared with 53.1 pg/ml reported for thalidomide. Moreover, they caused 69.33 and 77.74% reduction in NF-κB P65, respectively, compared with 60.26% reduction for thalidomide. Similarly, they reduced VEGF from 432.5 to 161.3 pg/ml and 132.8 pg/ml, respectively, in comparison to 153.2 pg/ml reported for thalidomide. The two new derivatives, 7d and 12 also showed about eightfold increases in caspase-8 levels in cells treated with them. These results were slightly better than those of thalidomide. The obtained results revealed that Compound 12 had better immunomodulatory properties than thalidomide, with stronger effects on TNF-α, NF-κB P65, VEGF and caspase-8.Conclusion: This work indicates that compounds 7d and 12 have interesting biological properties that should be further evaluated and modified in order to develop clinically useful thalidomide analogs.

Synthesis, enzyme inhibition assay, and molecular modeling study of novel pyrazolines linked to 4-methylsulfonylphenyl scaffold: antitumor activity and cell cycle analysis

Antitumor activity using 59 cancer cell lines and enzyme inhibitory activity of a newly synthesized pyrazoline-linked 4-methylsulfonylphenyl scaffold (compounds 18a-q) were measured and compared with those of standard drugs. Pyrazolines 18b, 18c, 18f, 18g, 18h, and 18n possessed significant antitumor activity, with a positive cytotoxic effect (PCE) of 22/59, 21/59, 21/59, 48/59, 51/59, and 20/59, respectively. The cancer cell lines HL60, MCF-7, and MDA-MB-231 were used to measure the IC50 values of derivatives 18c, 18g, and 18hvia the MTT assay method, and the results were compared with those of reference drugs. Derivatives 18g and 18h showed potent and broad-spectrum antitumor activities against HL60 (IC50 of 10.43, 8.99 μM, respectively), MCF-7 (IC50 of 11.7 and 12.4 μM, respectively), and MDA-MB-231 (IC50 of 4.07 and 7.18 μM, respectively). Compound 18c exhibited strong antitumor activity against HL60 and MDA-MB-231 cell lines with IC50 values of 8.43 and 12.54 μM, respectively, and moderate antitumor activity against MCF-7 cell lines with an IC50 value of 16.20 μM. Compounds 18c, 18g, and 18h remarkably inhibited VEGFR2 kinase (IC50 = 0.218, 0.168, and 0.135 μM, respectively) compared with the reference drug sorafenib (IC50 = 0.041 μM). Compounds 18g and 18h effectively inhibited HER2 kinase (IC50 = 0.496 and 0.253 μM, respectively) compared with erlotinib (IC50 = 0.085 μM). Compound 18h inhibited EGFR kinase (IC50 = 0.574 μM) with a potency comparable with that of the reference drug erlotinib (IC50 = 0.105 μM). Pyrazolines 18c, 18f, and 18h arrested the S/G2 phase of the cell cycle in HL-60 cells. In addition, derivatives 18c, 18f, and 18h revealed lower Bcl-2 protein expression anti-apoptotic levels and higher Bax, caspase-3, and caspase-9 expression levels. Molecular docking studies of derivative 18h into the binding sites of EGFR, HER2, and VEGFR2 kinases explored the interaction mode of these pyrazoline derivatives and their structural requirements for antitumor activity.

Antitumor Activity and Multi-Target Mechanism of Phenolic Schiff Bases Bearing Methanesulfonamide Fragments: Cell Cycle Analysis and a Molecular Modeling Study

Five phenolic Schiff bases (7-11) incorporating a fragment of methanesulfonamide were synthesized and evaluated for their efficacy as antitumor agents. Compounds 7 and 8 demonstrated the most potent antitumor action, with a positive cytotoxic effect (PCE) of 54/59 and 59/59 and a mean growth percentage (MG%) of 67.3% and 19.5%, respectively, compared with imatinib (PCE = 20/59 and MG% = 92.6%). The PCE values for derivatives 9-11 were 3/59, 4/59, and 4/59, respectively, indicating poor antitumor effect. Compound 8 exhibited the most significant efficacy, suppressing cell proliferation by an average of 50% at a dosage of 0.501 µM, in comparison with the reference drugs sorafenib (2.33 µM), gefitinib (2.10 µM), erlotinib (7.68 µM), and celecoxib (17.5 µM). Compounds 7 and 8 had substantial inhibitory effects on the human epidermal growth factor receptor 2 (HER2), with IC50 values of 0.183 μM and 0.464 μM, respectively. Furthermore, they exhibited significant inhibition of the epidermal growth factor receptor (EGFR), with IC50 values of 0.752 μM and 0.166 μM, respectively. Compound 8 exhibited the highest COX-2 inhibition (IC50 = 12.76 μM). We performed molecular docking dynamic experiments to examine the precise interaction and structural prerequisites for the anticancer activity of derivatives 7 and 8 by targeting EGFR and HER2.