Design, Synthesis, and Molecular Docking of Novel Miscellaneous Chalcones as p38α Mitogen-Activated Protein Kinase Inhibitors.

New chalcones were synthesized and evaluated to serve as p38-α type of mitogen-activated protein kinase (MAPK) inhibitors. According to the National Cancer Institute, the findings indicated that at a 10 µM dosage, compounds 3a and 6 were the most active among all the compounds examined, with mean growth inhibition% of 94.83 and 58.49, respectively. In 5-dose testing, they showed anticancer activity in the micro-molar range with GI50 in the range of 1.41-46.1 and 2.07-31.3 µM, respectively. Besides, powerful activity, especially against the leukaemia cell lines and good selectivity to cancer cells compared to normal PCS-800-017 with a selectivity index=12.41 and 23.77, respectively. Compounds 3a and 6 inhibited p38α MAPK with IC50 values of 0.1462±0.0063 and 0.4356±0.0189 µM, correspondingly. 3a showed good inhibition for HL-60(TB) cells and induced cell cycle arrest in HL-60(TB) cells at the G2/M phase. Besides, it elevated the total apoptosis by 14.68-fold and increased the caspase-3 level by 3.52-fold compared with doxorubicin, which raised it by 4.30-fold, inducing apoptosis by acting as caspase-dependent inducers. These results suggest that 3a is a promising antiproliferative and p38α MAPK inhibitor, confirmed by molecular docking with high compatibility 3a with the p38α MAPK binding site.

Topoisomerase II inhibitors design: Early studies and new perspectives.

The DNA topoisomerase enzymes are widely distributed throughout all spheres of life and are necessary for cell function. Numerous antibacterial and cancer chemotherapeutic drugs target the various topoisomerase enzymes because of their roles in maintaining DNA topology during DNA replication and transcription. Agents derived from natural products, like anthracyclines, epipodophyllotoxins and quinolones, have been widely used to treat a variety of cancers. A very active field of fundamental and clinical research is the selective targeting of topoisomerase II enzymes for cancer treatment. This thematic review summarizes the recent advances in the anticancer activity of the most potent topoisomerase II inhibitors (anthracyclines, epipodophyllotoxins and fluoroquinolones) their modes of action, and structure-activity relationships (SARs) organized chronologically in the last ten years from 2013 to 2023. The review also highlights the mechanism of action and SARs of promising new topoisomerase II inhibitors.

Design, synthesis, and biological evaluation of novel ciprofloxacin derivatives as potential anticancer agents targeting topoisomerase II enzyme.

A series of novel ciprofloxacin (CP) derivatives substituted at the N-4 position with biologically active moieties were designed and synthesised. 14 compounds were 1.02- to 8.66-fold more potent than doxorubicin against T-24 cancer cells. Ten compounds were 1.2- to 7.1-fold more potent than doxorubicin against PC-3 cancer cells. The most potent compounds 6, 7a, 7b, 8a, 9a, and 10c showed significant Topo II inhibitory activity (83-90% at 100 µM concentration). Compounds 6, 8a, and 10c were 1.01- to 2.32-fold more potent than doxorubicin. Compounds 6 and 8a induced apoptosis in T-24 (16.8- and 20.1-fold, respectively compared to control). This evidence was supported by an increase in the level of apoptotic caspase-3 (5.23- and 7.6-fold, sequentially). Both compounds arrested the cell cycle in the S phase in T-24 cancer cells while in PC-3 cancer cells the two compounds arrested the cell cycle in the G1 phase. Molecular docking simulations of compounds 6 and 8a into the Topo II active site rationalised their remarkable Topo II inhibitory activity.

In vivo- and in silico-driven identification of novel synthetic quinoxalines as anticonvulsants and AMPA inhibitors.

The lack of effective therapies for epileptic patients and the potentially harmful consequences of untreated seizure incidents have made epileptic disorders in humans a major health concern. Therefore, new and more potent anticonvulsant drugs are continually sought after, to combat epilepsy. On the basis of the pharmacophoric structural specifications of effective α-amino-3-hydroxy-5-methyl-4-isoxazolepropionic acid (AMPA) antagonists with an efficient anticonvulsant activity, the present work reports the design and synthesis of two novel sets of quinoxaline derivatives. The anticonvulsant activity of the synthesized compounds was evaluated in vivo according to the pentylenetetrazol-induced seizure protocol, and the results were compared with those of perampanel as a reference drug. Among the synthesized compounds, 24, 28, 32, and 33 showed promising activities with ED50 values of 37.50, 23.02, 29.16, and 23.86 mg/kg, respectively. Docking studies of these compounds suggested that AMPA binding could be the mechanism of action of these derivatives. Overall, the pharmacophore-based structural optimization, in vivo and in silico docking, and druglikeness studies indicated that the designed compounds could serve as promising candidates for the development of effective anticonvulsant agents with good pharmacokinetic profiles.

Design and synthesis of phthalazine-based compounds as potent anticancer agents with potential antiangiogenic activity via VEGFR-2 inhibition.

In the designed compounds, either a biarylamide or biarylurea moiety or an N-substituted piperazine motif was linked to position 1 of the phthalazine core. The anti-proliferative activity of the synthesised compounds revealed that eight compounds (6b, 6e, 7b, 13a, 13c, 16a, 16d and 17a) exhibited excellent broad spectrum cytotoxic activity in NCI 5-log dose assays against the full 60 cell panel with GI50 values ranging from 0.15 to 8.41 µM. Moreover, the enzymatic assessment of the synthesised compounds against VEGFR-2 tyrosine kinase showed the significant inhibitory activities of the biarylureas (12b, 12c and 13c) with IC50s of 4.4, 2.7 and 2.5 µM, respectively, and with 79.83, 72.58 and 71.6% inhibition of HUVEC at 10 µM, respectively. Additionally, compounds (7b, 13c and 16a) were found to induce cell cycle arrest at S phase boundary. Compound 7b triggered a concurrent increase in cleaved caspase-3 expression level, indicating the apoptotic-induced cell death.

Design and Synthesis of Pyridazine Containing Compounds with Promising Anticancer Activity.

Certain pyridazine containing compounds 2a-f, 3a, b, 4a, b, 5a, b, 6a and b were synthesized and characterized by spectroscopic means and elemental analysis. All the synthesized compounds were screened for their cytotoxic activity in vitro on colon cancer cell line (HCT-116) and breast cancer cell line (MCF-7). In addition, the antitumor activity of the synthesized compounds was tested in vivo against Ehrlich's ascites carcinoma (EAC) solid tumor grown in mice. The in vitro vascular endothelial growth factor receptor (VEGFR) enzyme inhibition assay was carried out for the most active compounds at a single dose of 10 µM. The obtained results revealed that compound 5b, which showed potent cytotoxic activity against HCT-116 also, exhibited the highest inhibition in the VEGFR kinase assay (92.2%).

New 3-Substituted-2-(4-hydroxyanilino)pyridine Derivatives: Synthesis, Antitumor Activity, and Tubulin Polymerization Inhibition.

A series of new pyridine derivatives 4a-c, 5a-d, 6a-d, 7a-f, and 8a-f structurally related to ABT-751 were synthesized and characterized by spectroscopic means and elemental analysis. All the synthesized compounds were tested for their cytotoxic activity in vitro against the HCT-116 and HepG-2 cancer cell lines using the MTT assay. The results showed that compound 8d has higher cytotoxic activity than the reference antimitotic agent colchicine, against both tested cell lines, with IC50 = 0.52 and 1.40 µM, respectively. The three most active compounds, 5d, 8b, and 8d, were further screened in vitro for inhibition of tubulin and showed remarkable results in comparison to colchicine.

Synthesis and cytotoxic activity of certain trisubstituted azetidin-2-one derivatives as a cis-restricted combretastatin A-4 analogues.

Novel series of 1,3,4-trisubstituted azetidin-2-one derivatives 8a-p were synthesized and proposed as cytotoxic agents acting via inhibition of tubulin at the colchicine binding site. The design of the target compounds was based upon modification in the structure of the vascular targeting agent combretastatin A-4 (CA-4). The cis double bond linker in CA-4 was replaced with the azetidin-2-one ring aiming to prevent the cis/trans isomerization that suppresses the activity of CA-4, thereby enhancing its antiproliferative activity. All new compounds were investigated in vitro against MCF-7 and HCT-116 cell lines. The inhibition of tubulin polymerization by four most potent compounds 8g, 8j, 8n and 8o was also evaluated. The synthesis of the final targets was achieved adopting Staudinger reaction. Molecular modeling studies were performed to rationalize the biological results.

Synthesis of New N1-Substituted-5-aryl-3-(3,4,5-trimethoxyphenyl)-2-pyrazoline Derivatives as Antitumor Agents Targeting the Colchicine Site on Tubulin.

A series of pyrazoline derivatives 2a-e, 3a-e and 4a-e structurally related to combretastatin A4 (CA-4) were synthesized and characterized by spectroscopic means and elemental analyses. In these compounds, the cis double bond of CA-4 was replaced with the pyrazoline ring aiming to enhance the cytotoxic effects displayed by CA-4 and to prevent the cis/trans isomerization that is associated with inactivation of CA-4. The cytotoxic activity of all new compounds was investigated in vitro against MCF-7 and HCT-116 cell lines. The inhibition of tubulin polymerization by the most active compounds 3d, 4a and e was evaluated. The cytotoxicity of 4e was correlated with induction of apoptosis and caspase-3 activation in vitro thus indicating the apoptotic pathway of anticancer effect of these compounds. Furthermore, in vivo evaluation of the synthesized compounds was carried out against Ehrlich's ascites carcinoma (EAC) solid tumor grown in mice. Compounds 2c, 3a and e showed significant reduction in tumor weight, and about 2-4 fold increase in caspase-3 expression.