Synthesis, Cytotoxic Properties and Tubulin Polymerization Inhibitory Activity of Novel 2-Pyrazoline Derivatives

Variations of VEGFR2 Chemical Space: Stimulator and Inhibitory Peptides

The kinase pathway plays a crucial role in blood vessel function. Particular attention is paid to VEGFR type 2 angiogenesis and vascular morphogenesis as the tyrosine kinase pathway is preferentially activated. In silico studies were performed on several peptides that affect VEGFR2 in both stimulating and inhibitory ways. This investigation aims to examine the molecular properties of VEGFR2, a molecule primarily involved in the processes of vasculogenesis and angiogenesis. These relationships were defined by the interactions between Vascular Endothelial Growth Factor receptor 2 (VEGFR2) and the structural features of the systems. The chemical space of the inhibitory peptides and stimulators was described using topological and energetic properties. Furthermore, chimeric models of stimulating and inhibitory proteins (for VEGFR2) were computed using the protein system structures. The interaction between the chimeric proteins and VEGFR was computed. The chemical space was further characterized using complex manifolds and high-dimensional data visualization. The results show that a slightly similar chemical area is shared by VEGFR2 and stimulating and inhibitory proteins. On the other hand, the stimulator peptides and the inhibitors have distinct chemical spaces.

Diverse Pharmacological Potential of different Substituted Pyrazole Derivatives

The chemistry of heterocyclic compounds has been a topic of research interest. Some five-membered heterocyclic compounds have been the subject of extensive research due to their different types of pharmacological effects. The five-membered nitrogen-containing heterocyclic compounds pyrazole, pyrazoline, and pyrazolone derivatives have a lot of interest in the fields of medical and agricultural chemistry due to their diverse spectrum of therapeutic activities. Various substituted pyrazole, pyrazoline, and pyrazolone compounds exhibited diverse pharmacological effects like Anti-microbial, anti-inflammatory, anti-tubercular, anti-fungal, anti-malarial, anti-diabetic, diuretic, anti-depressant, anticonvulsant, antioxidant, anti-leishmanial, antidiabetic, and antiviral, etc. In recent decades, the synthesis of numerous pyrazole, pyrazoline, and pyrazolone derivatives by different synthetic methods as well as research into their chemical and biological behavior have become more important. This review focuses on synthetic methods of the pyrazole, pyrazoline, and pyrazolone derivatives, which have significant biological properties and a variety of applications.

Pyrazoline derivatives as tubulin polymerization inhibitors with one hit for Vascular Endothelial Growth Factor Receptor 2 inhibition

In this work, to check the effect of the transposition of the rings in typical patterns, a series of pyrazoline derivatives 3a-3t bearing the characteristic 3,4,5-trimethoxy phenyl and thiophene moieties were synthesized and evaluated as tubulin polymerization inhibitors. Basically, as the concise output of our design, a majority of the synthesized compounds showed potency in inhibiting the tubulin polymerization. The top hit, 3q, exhibited potent anti-proliferation activity on cancer cell lines. It was comparable on tubulin-polymerization inhibition with the positive control Colchicine but lower toxic. The VEGFR2 inhibitory potency was introduced occasionally. The flow cytometry assay confirmed the apoptotic procedure and the confocal imaging revealed the tubulin-microtubule dynamics pattern. The anti-cancer mechanism of 3q was similar to Colchicine but not exactly the same on forming multi-polar spindles. The docking simulation visualized the possible binding patterns of 3q into tubulin and VEGFR2, respectively. The results inferred that further investigations on the transposition of the rings might lead to the improvement of tubulin polymerization inhibitory activity and the steadily introduction of the VEGFR2 inhibition.

Discovery of Anticancer Agents from 2-Pyrazoline-Based Compounds

As nitrogen-containing five-membered heterocyclic structural units, the substituted pyrazole derivatives have a broad spectrum of pharmacological activities, especially 4,5-dihydro-1H-pyrazoles that also commonly known as 2-pyrazolines. Since 2010, considerable studies have been found that the 2-pyrazoline derivatives possess potent anticancer activities. In the present review, it covers the pyrazoline derivatives reported by literature from 2010 till date (2010-2019). This review aims to establish the relationship between the anticancer activities variation and different substituents introduced into a 2-pyrazoline core, which could provide important pharmacophore clues for the discovery of new anticancer agents containing 2-pyrazoline scaffold.

Identification and characterization of SSE15206, a microtubule depolymerizing agent that overcomes multidrug resistance

Microtubules are highly dynamic structures that form spindle fibres during mitosis and are one of the most validated cancer targets. The success of drugs targeting microtubules, however, is often limited by the development of multidrug resistance. Here we describe the discovery and characterization of SSE15206, a pyrazolinethioamide derivative [3-phenyl-5-(3,4,5-trimethoxyphenyl)-4,5-dihydro-1H-pyrazole-1-carbothioamide] that has potent antiproliferative activities in cancer cell lines of different origins and overcomes resistance to microtubule-targeting agents. Treatment of cells with SSE15206 causes aberrant mitosis resulting in G2/M arrest due to incomplete spindle formation, a phenotype often associated with drugs that interfere with microtubule dynamics. SSE15206 inhibits microtubule polymerization both in biochemical and cellular assays by binding to colchicine site in tubulin as shown by docking and competition studies. Prolonged treatment of cells with the compound results in apoptotic cell death [increased Poly (ADP-ribose) polymerase cleavage and Annexin V/PI staining] accompanied by p53 induction. More importantly, we demonstrate that SSE15206 is able to overcome resistance to chemotherapeutic drugs in different cancer cell lines including multidrug-resistant KB-V1 and A2780-Pac-Res cell lines overexpressing MDR-1, making it a promising hit for the lead optimization studies to target multidrug resistance.

Antitumor potential of 1-thiocarbamoyl-3,5-diaryl-4,5-dihydro-1H-pyrazoles in human bladder cancer cells

Bladder cancer is a genitourinary malignant disease common worldwide. Current chemotherapy is often limited mainly due to toxicity and drug resistance. Thus, there is a continued need to discover new therapies. Recently evidences shows that pyrazoline derivatives are promising antitumor agents in many types of cancers, but there are no studies with bladder cancer. In order to find potent and novel chemotherapy drugs for bladder cancer, a series of pyrazoline derivatives 2a-2d were tested for their antitumor activity in two human bladder cancer cell lines 5647 and T24. The MTT assay showed that the compounds 1-thiocarbamoyl-3,5-diphenyl-4,5-dihydro-1H-pyrazole (2a) and 1-thiocarbamoyl-5-(4-chlorophenyl)-3-phenyl-4,5-dihydro-1H-pyrazole (2c) decrease the cell viability of 5637 cells. Molecular modeling indicated that these compounds had a good oral bioavailability and low toxicities. Clonogenic assay and flow cytometric analysis were used to assess colony formation, apoptosis induction and cell cycle distribution. Overall, our results suggest that pyrazoline 2a and 2c, with the substituents hydrogen and chlorine respectively, may decrease cell viability and colony formation of bladder cancer 5637 cell line by inhibition of cell cycle progression, and for pyrazoline 2a, by induction of apoptosis. As indicated by the physicochemical properties of these compounds, the steric factor influences the activity. Therefore, these pyrazoline derivatives can be considered promising anticancer agents for the treatment of bladder cancer.

Recent advances in iron complexes as potential anticancer agents

The iron complexes discussed in this review highlight their promising future as anticancer agents.

Phthalimide analogs as probable 15-lipoxygenase-1 inhibitors: synthesis, biological evaluation and docking studies

Background

Recent studies have been explained the role of lipoxygenases (LOX) in the origin of cancer. Among the lipoxygenases, the 5-LOX, 12-LOX and 15-LOX are more important in the cause of neoplastic disorders. In the present investigation, a new series of anticancer agents with 1,3,4-thiadiazole and phthalimide substructures were synthesized and their in vitro cytotoxicity was evaluated by MTT assay. Moreover, enzyme inhibitory potency was also assessed by enzymatic protocol towards 15-LOX-1. Molecular docking was performed to explore in silico binding mode of the target compounds.

Results

Tested compounds showed a better cytotoxic activity against HT29 cell line (colorectal cancer) in comparison with other cell lines (PC3: prostate carcinoma; SKNMC: neuroblastoma). Unfortunately, all of the tested derivatives rendered lower inhibitory potency than quercetin towards 15-LOX-1. Four hydrogen bonds were detected in docking studies for compound 4d as the most potent derivative in enzymatic assay.

Conclusions

The biological results of reported compounds in this research were not so satisfactory. But, further structural modifications are necessary to improve the bioactivity of these derivatives.

Synthesis, cytotoxicity, docking study, and tubulin polymerization inhibitory activity of novel 1-(3,4-dimethoxyphenyl)-5-(3,4,5-trimethoxyphenyl)-1H-1,2,4-triazole-3-carboxanilides

A series of novel 1-(3,4-methoxyphenyl)-5-(3,4,5-trimethoxyphenyl)-1H-1,2,4-triazole-3-carboxylic acid derivatives (4a-n) were synthesized and evaluated for their in vitro cytotoxic activity against the growth of four different human cell lines (hepatocarcinoma HepG2, breast adenocarcinoma MCF-7, colon carcinoma DLD-1, and leukemia HL-60). The anilides of m-anisidine 4e, o-anisidine 4f, and 3,5-difluoroaniline 4l demonstrated best results on MCF-7 cells and mean IC50 values of 7.79, 10.79, and 13.20 µM, respectively. The compounds produced a significant reduction in cellular microtubules at a concentration of 25 µg/mL, for microtubule loss. Molecular modeling studies involving compounds 4d, 4e, 4f, and 4l with the colchicine binding site of α,β-tubulin revealed hydrogen bonding and hydrophobic interactions with several amino acids in the colchicine binding site of β-tubulin.

Synthesis, DNA binding, hemolysis assays and anticancer studies of copper(II), nickel(II) and iron(III) complexes of a pyrazoline-based ligand

Background: Over the last few decades, metal-based drugs, particularly cisplatin and its analogs have been used for the treatment of various cancers. Currently, scientists are developing other metal complexes as anticancer agents to eliminate the toxicity associated with platinum drugs. Results: Claisen-Schmidt condensation was used to synthesize the pyrazoline-based ligand; (5-(4-chlorophenyl)-3-(4-fluorophenyl)-4,5-dihydro-1H-pyrazole-1-carbothioamide), followed by the synthesis of its complexes with copper(II), nickel(II) and iron(III) metal ions. DNA binding and in silico studies indicated quite good binding with DNA; requirements for good anticancer drugs. Conclusion: DNA binding constants for ligand, copper, nickel and iron complexes were 1.42 × 104, 3.16 × 104, 5.82 × 105 and 6.72 × 105 M-1, respectively, indicating strong binding with DNA. All the reported compounds were slightly hemolytic towards rabbit red blood corpuscles and exhibited moderate activities against MCF-7 cancer cell lines.