Jian-Feng Tang

Synthesis, biological evaluation, and molecular docking studies of 1,3,4-oxadiazole derivatives possessing 1,4-benzodioxan moiety as potential anticancer agents.

In present study, a series of new 1,3,4-oxadiazole derivatives containing 1,4-benzodioxan moiety (6a-6s) as potential telomerase inhibitors were synthesized. The bioassay tests demonstrated that compounds 6k, 6l, 6m, 6n and 6s exhibited broad-spectrum antitumor activity with IC(50) concentration range from 7.21 μM to 25.87 μM against the four cancer cell lines, HEPG2, HELA, SW1116 and BGC823. Moreover, all the title compounds were assayed for telomerase inhibition using the TRAP-PCR-ELISA assay. The results showed compound 6k possessed the most potent telomerase activity (IC(50)=1.27 ± 0.05 μM). Docking simulation was performed to position compound 6k into the active site of telomerase (3DU6) to determine the probable binding model.

Synthesis, biological evaluation, and molecular docking studies of resveratrol derivatives possessing chalcone moiety as potential antitubulin agents

Twenty-three resveratrol derivatives possessing chalcone moiety were synthesized and characterized, and their biological activities were also evaluated as potential antiproliferation and tubulin polymerization inhibitors. Compound C19 exhibited the most potent activity in vitro, which inhibited the growth of HepG2, B16-F10, and A549 cell lines with IC(50) values of 0.2, 0.1, and 1.4 μg/mL, respectively. Compound C19 also exhibited significant tubulin polymerization inhibitory activity (IC(50)=2.6 μg/mL). Docking simulation was performed to position compound C19 into the tubulin-colchicine binding site to determine the probable binding mode.

Synthesis, biological evaluation and molecular docking studies of 1,3,4-thiadiazole derivatives containing 1,4-benzodioxan as potential antitumor agents

A series of 1,3,4-thiadiazole derivatives containing 1,4-benzodioxan (2a-2s) have been synthesized to screen for FAK inhibitory activity. Compound 2p showed the most potent biological activity against HEPG2 cancer cell line (EC(50)=10.28 μg/mL for HEPG2 and EC(50)=10.79 μM for FAK), which was comparable to the positive control. Docking simulation was performed to position compound 2p into the FAK structure active site to determine the probable binding model. The results of antiproliferative and Western-blot assay demonstrated that compound 2p possessed good antiproliferative activity against HEPG2 cancer cell line. Therefore, compound 2p with potent FAK inhibitory activity may be a potential anticancer agent against HEPG2 cancer cell.

Design, modification and 3D QSAR studies of novel naphthalin-containing pyrazoline derivatives with/without thiourea skeleton as anticancer agents.

Two series of novel naphthalin-containing pyrazoline derivatives C1-C14 and D1-D14 have been synthesized and evaluated for their EGFR/HER-2 inhibitory and anti-proliferation activities. Compound D14 displayed the most potent activity against EGFR and A549 cell line (IC(50)=0.05 μM and GI(50)=0.11 μM), being comparable with the positive control Erlotinib (IC(50)=0.03 μM and GI(50)=0.03 μM) and more potent than our previous compounds C0-A (IC(50)=5.31 μM and GI(50)=33.47 μM) and C0-B (IC(50)=0.09 μM and GI(50)=0.34 μM). Meanwhile, compound C14 displayed the most potent activity against HER-2 and MCF-7 cell line (IC(50)=0.88 μM and GI(50)=0.35 μM), being a little less potent than Erlotinib (IC(50)=0.16 μM and GI(50)=0.08 μM) but far more potent than C0-A (IC(50)=6.58 μM and GI(50)=27.62 μM) and C0-B (IC(50)=2.77 μM and GI(50)=3.79 μM). The docking simulation was performed to analyze the probable binding models and the QSAR models were built for reasonable design of EGFR/HER-2 inhibitors at present and in future. The structural modification of introducing naphthalin moiety reinforced the combination of our compounds and the receptor, resulting in progress of bioactivity. Moreover, the replacement of thiourea skeleton by using benzene ring resulted in the slight diversity of the two series towards specific targets.

Design, synthesis and antibacterial activities of vanillic acylhydrazone derivatives as potential β-ketoacyl-acyl carrier protein synthase III (FabH) inhibitors.

Fatty acid biosynthesis is essential for bacterial survival. FabH, β-ketoacyl-acyl carrier protein (ACP) synthase III, is a particularly attractive target, since it is central to the initiation of fatty acid biosynthesis and is highly conserved among Gram-positive and Gram-negative bacteria. A series of acylhydrazone derivatives were synthesized and developed as potent inhibitors of FabH. This inhibitor class demonstrates strong broad-spectrum antibacterial activity. Compounds with potent antibacterial activities were tested for their Escherichia coli FabH inhibitory activity. Especially, compound E9 showed the most potent antibacterial activity with MIC values of 0.39-1.56 μg/mL against the tested bacterial strains and exhibited the most potent E. coli FabH inhibitory activity with IC(50) of 2.5 μM. Docking simulation was performed to position compound E9 into the E. coli FabH active site to determine the probable binding conformation.

Discovery and modification of sulfur-containing heterocyclic pyrazoline derivatives as potential novel class of β-ketoacyl-acyl carrier protein synthase III (FabH) inhibitors

A series of sulfur-containing heterocyclic pyrazoline derivatives (C1-C18; D1-D9) have been synthesized and purified (all are new except one) to be screened for FabH inhibitory activity. Compound C14 showed the most potent biological activity against Escherichia coli, Pseudomonas aeruginosa, Staphylococcus aureus and Bacillus subtilis (MIC values: 1.56-3.13 μg/mL), being comparable with the positive control, while D6 performed the best in the thiazolidinone series (MIC values: 3.13-6.25 μg/mL). They also demonstrated strong broad-spectrum antimicrobial activity. Compounds C14 and D6 exhibited the most potent E. coli FabH inhibitory activity with IC(50) of 4.6 and 8.4 μM, respectively, comparable with the positive control DDCP (IC(50)=2.8 μM). Docking simulation was performed to position compound C14 and D6 into the E. coli FabH structure active site to determine the probable binding model. The structurally modification of previous compounds and the attempt in innovative target have brought a positive progress.

Design, synthesis and biological evaluation of heterocyclic azoles derivatives containing pyrazine moiety as potential telomerase inhibitors

Three series of novel heterocyclic azoles derivatives containing pyrazine (5a-5k, 8a-8k and 11a-11k) have been designed, synthesized, structurally determined, and their biological activities were evaluated as potential telomerase inhibitors. Among the oxadiazole derivatives, compound 5c showed the most potent biological activity against SW1116 cancer cell line (IC(50)=2.46 μM against SW1116 and IC(50)=3.55 μM for telomerase). Compound 8h performed the best in the thiadiazole derivatives (IC(50)=0.78 μM against HEPG2 and IC(50)=1.24 μM for telomerase), which was comparable to the positive control. While compound 11f showed the most potent biological activity (IC(50)=4.12 μM against SW1116 and IC(50)=15.03 μM for telomerase) among the triazole derivatives. Docking simulation by positioning compounds 5c, 8h and 11f into the telomerase structure active site was performed to explore the possible binding model. The results of apoptosis demonstrated that compound 8h possessed good antitumor activity against HEPG2 cancer cell line. Therefore, compound 8h with potent inhibitory activity in tumor growth inhibition may be a potential antitumor agent against HEPG2 cancer cell. Therefore, the introduction of oxadiazole, thiadiazole and triazole structures reinforced the combination of our compounds and the receptor, resulting in progress of bioactivity.

Design, modification and 3D QSAR studies of novel 2,3-dihydrobenzo[b][1,4]dioxin-containing 4,5-dihydro-1H-pyrazole derivatives as inhibitors of B-Raf kinase.

Two series of novel 2,3-dihydrobenzo[b][1,4]dioxin-containing 4,5-dihydro-1H-pyrazole derivatives C1-C15 and D1-D15 have been synthesized and evaluated for their B-Raf inhibitory and anti-proliferation activities. Compound C14 ((3-(4-bromophenyl)-5-(2-fluorophenyl)-4,5-dihydro-1H-pyrazol-1-yl)(2,3-dihydrobenzo[b][1,4]dioxin-6-yl)methanone) showed the most potent biological activity against B-Raf(V600E) (IC(50) = 0.11 μM) and WM266.4 human melanoma cell line (GI(50) = 0.58 μM), being comparable with the positive control Erlotinib and more potent than our previous best compound, while D10 ((2,3-dihydrobenzo[b][1,4]dioxin-2-yl)(5-(3-fluorophenyl)-3-phenyl-4,5-dihydro-1H-pyrazol-1-yl)methanone) performed the best in the D series (IC(50) = 1.70 μM; GI(50) = 1.45 μM). The docking simulation was performed to analyze the probable binding models and poses and the QSAR model was built for reasonable design of B-Raf inhibitors in future. The introduction of 2,3-dihydrobenzo[b][1,4]dioxin structure reinforced the combination of our compounds and the receptor, resulting in progress of bioactivity.

Advances in the Researches on the Biological Activities and Inhibitors of Phosphatidylinositol 3-kinase

The PI3K/AKT/mTOR pathway is an intracellular signaling pathway, being important in apoptosis hence cancer such as breast cancer and non-small-cell lung cancer. It signaling axis controls cell proliferation and survival and has achieved major importance as a target for cancer therapy. The serine/threonine kinase Akt (also known as protein kinase B or PKB), since its initial discovery as a protooncogene, has become a major focus of attention because of its critical regulatory role in diverse cellular processes, including cancer progression and insulin metabolism. The Akt cascade is activated by receptor tyrosine kinases, integrins, B and T cell receptors, cytokine receptors, G protein coupled receptors and other stimuli that induce the production of phosphatidylinositol 3,4,5 triphosphates (PtdIns(3,4,5)P3) by phosphoinositide 3-kinase (PI3K). Therefore, PI3K plays an important role in in numerous cellular functions such as cell growth, proliferation, differentiation, motility, survival and intracellular trafficking. In this review, we introduced the structure of the PI3K, and then focused on its biological activities. In addition, we reviewed the advances in the researches of PI3K as well as related inhibitors over the last couple of decades. Finally, we also discussed the prospect and developmental trend of phosphatidylinositol 3-kinase as antitumor agents.

Design, synthesis, biological evaluation and molecular modeling of novel 1,3,4-oxadiazole derivatives based on Vanillic acid as potential immunosuppressive agents.

In present study, a series of novel 1,3,4-oxadiazole derivatives have been designed, synthesized and purified. All of these compounds are reported for the first time, the chemical structures of these compounds were confirmed by means of (1)H NMR, ESI-MS and elemental analyses. Besides, we evaluated their immunosuppressive activity. Most of these synthesized compounds were proved to have potent immunosuppressive activity and low toxicity. Among them, the bioassay results demonstrated that compounds 5c, 5n, 5p, 5o, 6f and 6g exhibited immunosuppressive activities with IC(50) concentration range from 1.25μM to 7.60 μM against the T cells, and the IC(50) of positive control (csa) is 2.12 μM. Moreover, all the title compounds were assayed for PI3K/AKT signaling pathway inhibition using the ELISA assay. We examined the compounds with potent inhibitory activities against IL-1, IL-6 and IL-10 released in ConA-simulated mouse lymph node cells. The results showed compounds 5o and 6f displayed the most potential biological activity against T cells (IC(50)=1.25 μM and 4.75 μM for T cells). The preliminary mechanism of compound 5o inhibition effects was also detected by flow cytometry (FCM). The results of apoptosis and ELISA assay demonstrated that the immunosuppressive activity of compounds 5o and 6f against T cells may be mediated by the inhibition of PI3Kγ/AKT signaling pathway. Molecular docking was performed to position compounds 5o and 6f into PI3Kγ binding site in order to indicate the potential target.