Design, Synthesis, Cytotoxic Screening and Molecular Docking Studies of Novel Hybrid Thiosemicarbazone Derivatives as Anticancer Agents

Novel tetrahydroisoquinolines as DHFR and CDK2 inhibitors: synthesis, characterization, anticancer activity and antioxidant properties

In this study, we synthesized new 5,6,7,8-tetrahydroisoquinolines and 6,7,8,9-tetrahydrothieno[2,3-c]isoquinolines based on 4-(N,N-dimethylamino)phenyl moiety as expected anticancer and/or antioxidant agents. The structure of all synthesized compounds were confirmed by spectral date (FT-IR, 1H NMR, 13C NMR) and elemental analysis. We evaluated the anticancer activity of these compounds toward two cell lines: A459 cell line (lung cancer cells) and MCF7 cell line (breast cancer cells). All tested compounds showed moderate to strong anti-cancer activity towards the two cell lines. Compound 7e exhibited the most potent cytotoxic activity against A549 cell line (IC50: 0.155 µM) while compound 8d showed the most potent one against MCF7 cell line (IC50: 0.170 µM) in comparison with doxorubicin. In addition, we examined the effect of compounds 7e and 8d regarding the growth of A549 and MCF7 cell lines, employing flow cytometry and Annexin V-FITC apoptotic assay. Our results showed that compound 7e caused cell cycle arrest at the G2/M phase with a 79-fold increase in apoptosis of A459 cell line. Moreover, compound 8d caused cell cycle arrest at the S phase with a 69-fold increase in apoptosis of MCF7 cell line. Furthermore, we studied the activity of these compounds as enzyme inhibitors against several enzymes. Our findings by docking and experimental studies that compound 7e is a potent CDK2 inhibitor with IC50 of 0.149 µM, compared to the Roscovitine control drug with IC50 of 0.380 µM. We also found that compound 8d is a significant DHFR inhibitor with an IC50 of 0.199 µM, compared to Methotrexate control drug with IC50 of 0.131 µM. Evaluation of the antioxidant properties of ten compounds was also studied in comparison with Vitamin C. Compounds 1, 3, 6, 7c and 8e have higher antioxidant activity than Vitamin C which mean that these compounds can used as potent antioxidant drugs.

A newly synthesized thiosemicarbazide derivative trigger apoptosis rather than necroptosis on HEPG2 cell line

Thiosemicarbazide derivatives have been the focus of scientists owing to their broad biological activities such as anticancer, antimicrobial, and anti-inflammatory. Herein, we designed and synthesized a new thiosemicarbazide derivative (TS-1) and evaluated its antiproliferative potential against the human hepatocellular carcinoma cell line (HEPG2) and human umbilical vein endothelial cell line (ECV-304). Also, it was aimed to investigate the necroptotic and apoptotic cell death effects of TS-1 in HEPG2 cells, and these effects were supported by molecular docking. The new synthesized compound structure was characterized using various spectroscopic methods such as FT-IR, 1 H-NMR, 13 C-NMR, and elemental analysis. The cytotoxic activity of the tested compound was measured by the MTT assay. Apoptotic and necroptotic properties of the TS-1 were evaluated by indirect immunoperoxidase method using antibodies against Ki-67, Bax, Bcl-2, caspase-3, caspase-8, caspase-9, RIP3, and RIPK1. Apoptotic and necroptotic effects of TS-1 were supported by molecular docking. Compound TS-1 was synthesized as a pure compound with a high yield. The effective value of TS-1 was 10 μM in HEPG2 cells. TS-1 did not show any cytotoxic effect on ECV-304. Caspase-3 and RIPK1 immunoreactivities were significantly increased in HEPG2 cells after being treated with TS-1. As the results of the molecular docking studies, the molecular docking showed that the TS-1 exhibits H-bond interaction with various significant amino acid residues in the active site of both RIPK1. It could be concluded that TS-1 could be a promising novel therapeutic agent by inducing apoptosis rather than necroptosis in HEPG2 cells.

Novel 3-(pyrazol-4-yl)-2-(1H-indole-3-carbonyl)acrylonitrile derivatives induce intrinsic and extrinsic apoptotic death mediated P53 in HCT116 colon carcinoma

A novel series of α-cyano indolylchalcones was prepared, and their chemical structures were confirmed based on the different spectral data. Among them, compound 7f was observed to be the most effective bioactive chalcone with distinguished potency and selectivity against colorectal carcinoma (HCT116) with IC50 value (6.76 µg/mL) relative to the positive control (5 FU) (77.15 µg/mL). In a preliminary action study, the acrylonitrile chalcone 7f was found to enhance apoptotic action via different mechanisms like inhibition of some anti-apoptotic protein expression, regulation of some apoptotic proteins, production of caspases, and cell cycle arrest. All mechanisms suggested that compound 7f could act as a professional chemotherapeutic agent. Also, a molecular docking study was achieved on some selected proteins implicated in cancer (Caspase 9, XIAP, P53 mutant Y220C, and MDM2) which showed variable interactions with compound 7f with good Gibbs free energy scores.

In vitro cytotoxic investigation of some synthesized 1,6-disubstituted-1-azacoumarin derivatives as anticancer agents

Aims: In this study, novel synthesized 1,6-disubstituted-1-azacoumarin-3-carboxylic acid derivatives were designed, synthesized and evaluated as potential anticancer agents. Materials & methods: The cytotoxicity of novel 1-azacoumarin-3-carboxylic acid derivatives was tested using an MTT assay. High potency was shown by DNA flow cytometry on MCF-7 cells for compound 3b. In addition, topoisomerase IIβ, caspase 3/7, Bax and Bcl-2 enzymes were used to study apoptotic activity. In the same studies, molecular docking analysis assessed activity. Results & conclusion: Cytotoxicity screening identified multiple bioactive compounds, especially compound 3b. Analysis of DNA flow cytometry revealed that compound 3b exhibited cell cycle arrest. Compound 3b had an increase in the expression of Bax/Bcl-2 ratio and caspase 3/7, and a decrease in topoisomerase IIβ enzyme inhibition.

Design, synthesis, in vitro anticancer, molecular docking and SAR studies of new series of pyrrolo[2,3-d]pyrimidine derivatives

The current study involves the design and synthesis of a newly synthesized pyrrolo[2,3-d]pyrimidine derivatives to contain chlorine atoms in positions 4 and 6 and trichloromethyl group in position 2 using microwave technique as a new and robust approach for preparation of this type of pyrrolo[2,3-d]pyrimidine derivatives. The chemical structure of the synthesized pyrrolo[2,3-d]pyrimidine derivatives 3-19 was well-characterized using spectral and elemental analyses as well as single-crystal X-ray diffraction. All compounds were tested in vitro against seven selected human cancer cell lines, namely, MCF7, A549, HCT116, PC3, HePG2, PACA2 and BJ1 using MTT assay. It was found that compounds 14a, 16b and 18b were the most active toward MCF7 with IC50 (1.7, 5.7, and 3.4 μg/ml, respectively) relative to doxorubicin (Dox.) (26.1 μg/ml). Additionally, compound 17 exerted promising cytotoxic effects against HePG2 and PACA2 with IC50 (8.7 and 6.4 μg/ml, respectively) relative to Dox. (21.6 and 28.3 μg/ml, respectively). The molecular docking study confirmed our ELISA result which showed the promising binding affinities of compounds 14a and 17 against Bcl2 anti-apoptotic protein. At the gene expression level, P53, BAX, DR4 and DR5 were up-regulated, while Bcl2, Il-8, and CDK4 were down-regulated in 14a, 14b and 18b treated MCF7 cells. At the protein level, compound 14b increased the activity of Caspase 8 and BAX (18.263 and 14.25 pg/ml) relative to Dox. (3.99 and 4.92 pg/ml, respectively), while the activity of Bcl2 was greatly decreased in 14a treated MCF7 (2.4 pg/ml) compared with Dox. (14.37 pg/ml). Compounds 14a and 14b caused cell cycle arrest at the G1/S phase in MCF7. Compounds 16b and 18b induced the apoptotic death of MCF7 cells. In addition, the percentage of fragmented DNA was increased significantly in 14a treated MCF7 cells.

Combined Bioinformatics and Combinatorial Chemistry Tools to Locate Drug-Able Anti-TB Phytochemicals: A Cost-Effective Platform for Natural Product-Based Drug Discovery

Based on extensive experimental studies, a huge number of phytochemicals showed potential activity against tuberculosis (TB) at a lower minimum inhibitory concentration (MIC) and fewer toxicity profiles. However, these promising drugs have not been able to convert from 'lead' to 'mainstream' due to inadequate drug-ability profiles. Thus, early drug-prospective analyses are required at the primary stage to accelerate natural-product-based drug discovery with limited resources and time. In the present study, we have selected seventy-three potential anti-TB phytochemicals (MIC value ≤10 μg/mL) and assessed the drug-ability profiles using bioinformatics and combinatorial chemistry tools, systematically. Primarily, the molecular docking study was done against two putative drug targets, catalase-peroxidase enzyme (katG) and RNA polymerase subunit-β (rpoB) of Mycobacterium tuberculosis (Mtb) using AutoDock 4.2 software. Further, assessed the drug-ability score from Molsoft, toxicity profiles from ProTox, pharmacokinetics from SwisADME, hierarchical cluster analysis (HCA) by ChemMine tools and frontier molecular orbitals (FMOs) with Avogadro and structural activity relationships (SAR) analysis with ChemDraw 18.0 software. Above analyses indicated that, lower MIC exhibited anti-TB phytochemicals, abietane, 12-demethylmulticaulin exhibited poor docking and drug-ability scores, while tiliacorinine, 2-nortiliacorinine showed higher binding energy and drug-ability profiles. Overall, tiliacorinine, 2-nortiliacorinine, 7α-acetoxy-6β-hydroxyroyleanone (AHR), (2S)-naringenin and isovachhalcone were found as the most active and drug-able anti-TB candidates from 73 candidates. Phytochemicals are always a vital source of mainstream drugs, but the MIC value of a phytochemical is not sufficient for it to be promoted. An ideal drug-ability profile is therefore essential for achieving clinical success, where advanced bioinformatics tools help to assess and analyse that profile. Additionally, several natural pharmacophores found in existing anti-TB drugs in SAR analyses also provide crucial information for developing potential anti-TB drug. As a conclusion, combined bioinformatics and combinatorial chemistry are the most effective strategies to locate potent-cum-drug-able candidates in the current drug-development module.

(Z)-2-(1-(5-Methyl-1-(4-nitrophenyl)-1H-1,2,3-triazol-4-yl)ethylidene)-N-phenylhydrazine-1-carbothioamide

Reaction of equimolar equivalents of 1-(5-methyl-1-(4-nitrophenyl)-1H-1,2,3-triazol-4-yl)ethan-1-one (1) and N-phenylhydrazinecarbothioamide (2) in boiling ethanol containing a catalytic amount of concentrated hydrochloric acid for 4 h gave (Z)-2-(1-(5-methyl-1-(4-nitrophenyl)-1H-1,2,3-triazol-4-yl)ethylidene)-N-phenylhydrazine-1-carbothioamide (3) with 88% yield. The structure of 3 was established using single-crystal X-ray diffraction and magnetic resonance spectroscopy.

New benzimidazole based hybrids: Synthesis, molecular modeling study and anticancer evaluation as TopoII inhibitors

Three series of new benzimidazole hybrids were designed and synthesized as promising human TopoII inhibitors. They were characterized by different spectroscopic techniques (¹H, ¹³C NMR, ESI-MS and IR). All hybrids (6-23) were screened for their in vitro antiproliferative activity against five human cancer cell lines namely; HepG-2, MCF-7, PC-3, HCT-116 and Hela. Compound 21 showed the most potent anticancer activity against all cancer cell lines, with IC₅₀ range of 2.82 to 12.59 µM, while proving safe towards normal cells WI-38 (IC₅₀ = 31.89 µM) compared to the reference drug doxorubicin (IC₅₀ = 6.72 µM). The most active candidates 13, 20, 21, 22 and 23 were further assessed for their human TopoII inhibition. The best of which, compounds 13 and 20 showed IC₅₀ of 6.72 and 8.18 µM respectively compared to staurosporine (IC₅₀ = 4.64 µM). Further mechanistic studies for compound 13 showed cell cycle arrest at S-phase by 51.29 % and a significant increase in the total apoptosis by 62.5 folds. Furthermore, apoptosis study proved that it induced apoptosis by decreasing both IAP and Bcl-2, activating caspases 3, 8 and 9, and increasing accumulation of ROS in HepG-2 cells. Besides, it decreased transcription factors' binding activity to DNA. Comparative molecular docking study was performed between the most potent TopoII inhibitors 13 and 20, and the least potent one 23 to relate the binding pattern with TopoII catalytic active site to the biological activity, where all results came in agreement with the biological results. Additional molecular modeling studies including surface mapping and contact preferences were performed to emphasize the importance of hydrophobicity. Physicochemical calculations were assessed where compounds 13 and 20 represented very promising orally active drug candidates.