Synthesis and cytotoxic evaluation of novel quinazolinone derivatives as potential anticancer agents.

Nitrogen-rich heterocyclic compounds represent a unique class of chemicals with especial properties and have been modified to design novel pharmaceutically active compounds. In this study, a series of novel quinazolinone derivatives with substituted quinoxalindione were synthesized in two parts. In the first part, 6-(4-amino-3-methylphenoxy)quinoxaline-2,3(1H,4H)-dione was prepared from para-amino -m-crozol in 5 steps. In the next part, 2-alkyl-4H-benzo[d][1,3]oxazin-4-one derivatives were obtained from antranilic acid. Then reaction of 6-(4-amino-3-methylphenoxy)quinoxaline-2,3(1H,4H)-dione with 2-alkyl-4H-benzo[d][1,3]oxazin-4-one derivatives resulted in the production of final componds. The structures of synthesized compounds were confirmed by IR and 1H-NMR. Cytotoxic activity of the compounds were evaluated at 0.1, 1, 10, 50 and 100 µM concentrations against MCF-7 and HeLa cell lines using the 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) colorimetric assay. Almost all new compounds showed cytotoxic activity in both cell lines. Among tested compounds, 11g displayed the highest cytotoxic activity against both cell lines.

Synthesis and In vitro/In vivo Characterization of Raloxifene Grafted Poly(Styrene Maleic Acid)-Poly(Amide-Ether-Ester-Imide) Micelles for Targeted Delivery of Docetaxel in G Protein-Coupled Estrogen Receptor Breast Cancer.

BACKGROUND: To reduce the nonspecifically distribution of chemotherapeutic agents throughout the whole body, which causes severe toxicity in normal tissues, targeting them towards a receptor overexpressed on tumor tissue, is a promising method for cancer therapy. OBJECTIVE: The aim of the present study was development of novel copolymeric micelles of raloxifene targeted Styrene Maleic Acid-Poly Amide Ether Ester Imide-Poly Ethylene Glycol (SMA-PAEEI-PEG-RA) and loading them with Docetaxel (DTX). METHODS: Successful synthesis of the targeted copolymer was confirmed by FTIR and C-NMR spectroscopy. The micelles physicochemical properties like morphology, particle size, poly dispersity index, zeta potential, drug loading, release, stability, in vitro cytotoxicity and cellular uptake were analyzed. The in vivo antitumor activity of DTX-loaded micelles were assessed and compared with free DTX and non-targeted micelles in breast cancer bearing Balb-c mice. RESULTS: Particle sizes, zeta potentials and the encapsulation efficiency of the drug in targeted micelles were 115.9- 142.8 nm, -4.9 to -12.9 mV, and 54.1-67.8%, respectively. Cell toxicity tests showed that IC50 of DTX-loaded SMAPAEEI- PEG-RA micelles increased five-fold as compared with free DTX. Survival rate of the mice improved more effectively than free DTX so that, the percentage of increase in lifespan (ILS%) and the tumor inhibition ratio (TIR) changed from 41.66% and 51.19% in free drug to 83.33% and 78.57% in the targeted micelles, respectively. CONCLUSION: Therefore, the raloxifene conjugated PEG-derived micelles may provide a novel and effective delivery system for DTX in breast cancer.

Synthesis and cytotoxic evaluation of some novel quinoxalinedione diarylamide sorafenib analogues.

A series of novel sorafenib analogues containing a quinoxalinedione ring and amide linker were synthesized. A total of 9 novel compounds in 6 synthetic steps were synthesized. Briefly, the amino group of p-aminophenol was first protected which then followed by O-arylation with 5-chloro-2-nitroaniline to provide compound d. Reduction of the nitro group of compound d and cyclization of the diamine group of compound e with oxalic acid afforded compound f which on deacetylation yeilded compound g. Then compound g was reacted with different acyl halides to afford the target compounds 1h-1p. Chemical structures of synthesized compounds were confirmed by 1H NMR and FT-IR analysis. All compounds were evaluated at 1, 10, 50 and 100 µM concentrations for their cytotoxicity against HeLa and MCF-7 cancer cell lines. Some of the compounds showed good cytotoxic activity, especially compounds 1i and 1k-1n with the IC50 values of 19, 16, 22, 18, and 16 µM against MCF-7 cell line and 20, 18, 25, 20, and 18 µM against HeLa cell line, respectively.

Synthesis and characterization of some novel diaryl urea derivatives bearing quinoxalindione moiety.

Diaryl urea derivatives have exhibited a broad spectrum of biochemical effects and pharmaceutical applications. Several diaryl urea derivatives such as sorafenib, regorafenib, linifanib, and tivozanib and lenvatinib are in clinical trial or clinical use. Therefore, development of small molecules within the diaryl urea scaffold with the ability of binding to variety of enzymes and receptors in the biological system are an interesting topic for researchers. Sorafenib as a diaryl urea derivative is a well-known anticancer agent. Corresponding to available information about biological activities of quinoxaline moieties, based on sorafenib scaffold, several structures were designed by replacement of pyridyl carboxamide group of sorafenib with quinoxalindione moiety. A total of 14 novel compounds in 7 synthetic steps were synthesized. Briefly, the amino group of p-aminophenol was first protected followed by O-arylation of 4-acetamidophenol with 5-chloro-2-nitroaniline to provide 5-(4-acetamidophenoxy)-2-nitroaniline. Reduction of the nitro group of 5-(4-acetamidophenoxy)-2-nitroaniline and cyclization of diamine N-(4-(3,4-diaminophenoxy) phenyl) acetamides with oxalic acid afforded compound N-(4-((2,3-dioxo-1,2,3,4-tetrahydroquinoxalin-6-yl)oxy)phenyl) acetamides which on deacetylation gave compounds 6-(4-aminophenoxy) quinoxaline-2,3 (1H, 4H)-diones. Then resultant compounds, 6-(4-aminophenoxy) quinoxaline-2,3 (1H, 4H)-diones were reacted by appropriate isocyanates/ carbamates to give the target compounds 1-(4-((2,3-dioxo-1,2,3,4-tetrahydroquinoxalin-6-yl)oxy)phenyl)-3-phenylureas. The structures of compounds confirmed by proton nuclear magnetic resonance (1H NMR), mass spectrum and Fourier transform infrared (FT-IR).

Biological evaluation, docking and molecular dynamic simulation of some novel diaryl urea derivatives bearing quinoxalindione moiety.

In this study a series of diarylurea derivatives containing quinoxalindione group were biologically evaluated for their cytotoxic activities using MTT assay against MCF-7 and HepG2 cell lines. Antibacterial activities of these compounds were also evaluated by Microplate Alamar Blue Assay (MABA) against three Gram-negative (Escherichia coli, Pseudomonas aeruginosa and Salmonella typhi), three Gram-positive (Staphylococcus aureus, Bacillus subtilis and Listeria monocitogenes) and one yeast-like fungus (Candida albicans) strain. Furthermore, molecular docking was carried out to study the binding pattern of the compounds to the active site of B-RAF kinase (PDB code: 1UWH). Molecular dynamics simulation was performed on the best ligand (16e) to investigate the ligand binding dynamics in the physiological environment. Cytotoxic evaluation revealed the most prominent cytotoxicity for 6 compounds with IC50 values of 10-18 µM against two mentioned cell lines. None of the synthesized compounds showed significant antimicrobial activity. The obtained results of the molecular docking study showed that all compounds fitted in the binding site of enzyme with binding energy range of -11.22 to -12.69 kcal/mol vs sorafenib binding energy -11.74 kcal/mol as the lead compound. Molecular dynamic simulation indicated that the binding of ligand (16e) was stable in the active site of B-RAF during the simulation.

Synthesis and evaluation of antimicrobial activity of cyclic imides derived from phthalic and succinic anhydrides.

Cyclic imides are a group of compounds which have valuable biological properties including cytotoxic, anti-inflammatory, antibacterial and antifungal activities. In this study, succinic and phthalic anhydrides were treated with glycinamide in pyridine to yield the corresponding amic acids. These amic acids underwent ring closure with acetic anhydride and anhydrous sodium acetate to form cyclic imides. In another procedure, succinic and phthalic anhydrides upon reaction with 2-amino-benzylamine in pyridine gave the corresponding cyclic imides. The imides were screened for their antimicrobial activities against three types of bacteria and one type of fungi. Phthalimide derived from benzylamine exhibited remarkable antimicrobial activity against E. coli.

A quantitative structure-activity relationship (QSAR) study of some diaryl urea derivatives of B-RAF inhibitors.

In the current study, both ligand-based molecular docking and receptor-based quantitative structure activity relationships (QSAR) modeling were performed on 35 diaryl urea derivative inhibitors of V600EB-RAF. In this QSAR study, a linear (multiple linear regressions) and a nonlinear (partial least squares least squares support vector machine (PLS-LS-SVM)) were used and compared. The predictive quality of the QSAR models was tested for an external set of 31 compounds, randomly chosen out of 35 compounds. The results revealed the more predictive ability of PLS-LS-SVM in analysis of compounds with urea structure. The selected descriptors indicated that size, degree of branching, aromaticity, and polarizability affected the inhibition activity of these inhibitors. Furthermore, molecular docking was carried out to study the binding mode of the compounds. Docking analysis indicated some essential H-bonding and orientations of the molecules in the active site.