Background: Nowadays, removal of heavy metals from the environment is an important problem due to their toxicity. Objectives: In this study, a modified method was used to synthesize chitosan-coated magnetite nanoparticles (CCMN) to be used as a low cost and nontoxic adsorbent. CCMN was then employed to remove Hg 2+ from water solutions. Materials and Methods: To remove the highest percentage of mercury ions, the Box-Behnken model of response surface methodology (RSM) was applied to simultaneously optimize all parameters affecting the adsorption process. Studied parameters of the process were pH (5-8), initial metal concentration (2-8 mg/L), and the amount of damped adsorbent (0.25-0.75 g). A second-order mathematical model was developed using regression analysis of experimental data obtained from 15 batch runs. Results: The optimal conditions predicted by the model were pH = 5, initial concentration of mercury ions = 6.2 mg/L, and the amount of damped adsorbent = 0.67 g. Confirmatory testing was performed and the maximum percentage of Hg 2+ removed was found to be 99.91%. Kinetic studies of the adsorption process specified the efficiency of the pseudo second-order kinetic model. The adsorption isotherm was well-fitted to both the Langmuir and Freundlich models. Conclusions: CCMN as an excellent adsorbent could remove the mercury ions from water solutions at low and moderate concentrations, which is the usual amount found in environment.

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Background: The microtubule is composed of αβ-tubulin heterodimers and is an attractive target for the design of anticancer drugs. Over the years, various compounds have been developed and their effect on tubulin polymerization has been studied. Despite a great efforts to make an effective drug, no drug has been introduced which inhibit colchicine binding site. Objective: In the current work a series of pyrimidine derivatives were designed and synthesized. Furthermore their cytotoxic activities were evaluated and molecular docking studies were performed. Methods: Twenty compounds of pyrimidine were synthesized in 2 different groups. In the first group, 4,6-diaryl pyrimidine was connected to the third aryl group via thio-methylene spacer. In the second group, this linker was substituted by S-CH2- triazole moiety. The cytotoxic activity of these compounds was evaluated against 4 different cell lines (HT-29, MCF-7, T47D, NIH3T3). Results: Compounds 6d, 6m, 6p showed potent cytotoxic activity against MCF7 cancerous cell lines. Between these compounds, compound 6p did not show cytotoxic activity against NIH- 3T3 (normal cell) cell line. Docking studies show that these compounds occupy colchicine binding site in tubulin protein and probably their anticancer mechanism is inhibition of tubulin polymerization. Conclusion : Altogether, with respect to obtained results, it is attractive and beneficial to further investigation on pyrimidine scaffold as antimitotic agents. Attention to the selectivity index of 6p on MCF7 cell line could be valuable in design new chemical agents for treatment of breast cancer.