Halloysite Nanoclay with High Content of Sulfonic Acid-Based Ionic Liquid: A Novel Catalyst for the Synthesis of Tetrahydrobenzo[b]pyrans

One of the main drawbacks of supported ionic liquids is their low loading and consequently, low activity of the resultant catalysts. To furnish a solution to this issue, a novel heterocyclic ligand with multi imine sites was introduced on the surface of amino-functionalized halloysite support via successive reactions with 2,4,6-trichloro-1,3,5-triazine and 2-aminopyrimidine. Subsequently, the imine sites were transformed to sulfonic acid-based ionic liquids via reaction with 1,4-butanesultone. Using this strategy, high loading of ionic liquid was loaded on halloysite nanoclay. The supported ionic liquid was then characterized with XRD, SEM, TEM, EDS, FTIR, BET, TGA and elemental mapping analysis and utilized as a metal-free Brønsted acid catalyst for promoting one-pot reaction of aldehydes, dimedone and malononitrile to furnish tetrahydrobenzo[b]pyrans. The catalytic tests confirmed high performance of the catalyst. Moreover, the catalyst was stable upon recycling

A Comparison between the Cytotoxicity Induced by Gossypol in Two Testicular Cell Lines

Background: Gossypol is a yellow toxic pigment from the cottonseed that can cause acute or chronic toxicity in humans and animals by affecting the testicular tissues. Nowadays cottonseed is used as food supplement for ruminants specially the sheep. In this study, two different stem cell lines of testicular tissue including GC1-spg (mouse testis) and SFTF-PI43 (sheep testis) cells were used to evaluation of gossypol cytotoxicity. Methods: The GC-1spg and the SFTF_PI43 cells were cultured in RPMI-1640 supplemented with fetal bovine serum (10%) and antibiotic (penicillin 105/ml, streptomycin100μg/ml), and then 5×104 cells/well were seeded in 24 well plates. Cultured cells were exposed to four different concentrations of gossypol (1.25, 2.5, 5 and 10μM). After 24 h incubation, cells viability test was performed using Trypan Blue dye exclusion and MTT assay. The Thiobarbituric Acid Reacting Substances (TBARS) and Ferric Reducing Activity Potential (FRAP) assays was performed on media. Result: In high concentrations (over than 2.5μM), Gossypol showed cytotoxic effects on cells. The IC50 for gossypol (using MTT assays) on SFTF-PI43 and GC-1spg cell lines was 2.2 μM and 3.2 μM, respectively. While the results for FRAP assay did not show any significant differences between the test and control groups, significantly higher lipid peroxidation was observed in SFTF-PI43 cells that were treated with higher doses of gossypol (10μM). Conclusion: In this research, we found that gossypol has cytotoxic effects on both examined testicular cell lines and increased lipid peroxidation, which is a probable mechanism of its toxicity on cell lines