Nitrophenyl-group-containing Heterocycles. Part I. Synthesis, Characterization, Anticancer Activity and Antioxidant Properties of Some New 5,6,7,8-tetrahydro-isoquinolines Bearing 3(4)-nitrophenyl Group

Regioselective cyclocondensation of 2,4-diacetyl-5-hydroxy-5-methyl-3-(3-nitrophenyl/4-nitrophenyl)cyclohexanones 1a,b with cyanothioacetamide afforded the corresponiing 7-acetyl-4-cyano-1,6-dimethyl-6-hydroxy-8-(3-nitrophenyl/4-nitrophenyl)-5,6,7,8-tetrahydro-soquinoline-3(2H)-thiones 2a,b in 93-96% yield. Reaction of compounds 2a,b with some ethyl iodide, 2-chloroacetamide (4a) or its N-aryl derivatives 4b-e by refluxing in ethanol, in the presence of slightly excess molar amounts of sodium acetate trihydrate, for one hour gave 3-ethylthio-5,6,7,8-tetrahydro-isoquinoline 3 and (5,6,7,8-tetrahydroisoquinolin-3-ylthio)acetamides 5a-i, respectively. On heating compounds 5b-d,f,g in ethanol containing a catalytic amount of sodium carbonate, they converted into their isomeric 1-amino- 6,7,8,9-tetrahydrothieno[2,3-c]isoquinoline-2-carboxamides 6b-d,f,g. Structural formulae of all synthesized compounds were characterized on the basis of their elemental analyses and spectroscopic data. Also, the biological evaluation of the synthesized isoquinolines as anticancer and antioxidant agents have been carried out and the obtained results are reported herein.

Solid Lipid Nanoparticles Administering Antioxidant Grape Seed-Derived Polyphenol Compounds: A Potential Application in Aquaculture

The supply of nutrients, such as antioxidant agents, to fish cells still represents a challenge in aquaculture. In this context, we investigated solid lipid nanoparticles (SLN) composed of a combination of Gelucire® 50/13 and Precirol® ATO5 to administer a grape seed extract (GSE) mixture containing several antioxidant compounds. The combination of the two lipids for the SLN formation resulted in colloids exhibiting mean particle sizes in the range 139–283 nm and zeta potential values in the range +25.6–43.4 mV. Raman spectra and X-ray diffraction evidenced structural differences between the free GSE and GSE-loaded SLN, leading to the conclusion that GSE alters the structure of the lipid nanocarriers. From a biological viewpoint, cell lines from gilthead seabream and European sea bass were exposed to different concentrations of GSE-SLN for 24 h. In general, at appropriate concentrations, GSE-SLN increased the viability of the fish cells. Furthermore, regarding the gene expression in those cells, the expression of antioxidant genes was upregulated, whereas the expression of hsp70 and other genes related to the cytoskeleton was downregulated. Hence, an SLN formulation containing Gelucire® 50/13/Precirol® ATO5 and GSE may represent a compelling platform for improving the viability and antioxidant properties of fish cells.

Green Synthesis of Oxoquinoline-1(2H)-carboxamide as Antiproliferative and Antioxidant Agents: An Experimental and In-Silico Approach to High Altitude Related Disorders

At high altitudes, drops in oxygen concentration result in the creation of reactive oxygen and nitrogen species (RONS), which cause a variety of health concerns. We addressed these health concerns and reported the synthesis, characterization, and biological activities of a series of 10 oxoquinolines. N-Aryl-7-hydroxy-4-methyl-2-oxoquinoline-1(2H)carboxamides (5a–j) were accessed in two steps under ultrasonicated irradiation, as per the reported method. The anticancer activity was tested at 10 µM against a total of 5 dozen cancer cell lines obtained from nine distinct panels, as per the National Cancer Institute (NCI US) protocol. The compounds 5a (TK-10 (renal cancer); %GI = 82.90) and 5j (CCRF-CEM (Leukemia); %GI = 58.61) showed the most promising anticancer activity. Compound 5a also demonstrated promising DPPH free radical scavenging activity with an IC50 value of 14.16 ± 0.42 µM. The epidermal growth factor receptor (EGFR) and carbonic anhydrase (CA), two prospective cancer inhibitor targets, were used in the molecular docking studies. Molecular docking studies of ligand 5a (docking score = −8.839) against the active site of EGFR revealed two H-bond interactions with the residues Asp855 and Thr854, whereas ligand 5a (docking = −5.337) interacted with three H-bond with the residues Gln92, Gln67, and Thr200 against the active site CA. The reported compounds exhibited significant anticancer and antioxidant activities, as well as displayed significant inhibition against cancer targets, EGFR and CA, in the molecular docking studies. The current discovery may aid in the development of novel compounds for the treatment of cancer and oxidative stress, and other high altitude-related disorders.

In Vivo and Ex Vivo Evaluation of 1,3-Thiazolidine-2,4-Dione Derivatives as Euglycemic Agents

Thiazolidinediones (TZDs), used to treat type 2 diabetes mellitus, act as full agonists of the peroxisome proliferator-activated receptor gamma. Unfortunately, they produce adverse effects, including weight gain, hepatic toxicity, and heart failure. Our group previously reported the design, synthesis, in silico evaluation, and acute oral toxicity test of two TZD derivatives, compounds 40 (C40) and 81 (C81), characterized as category 5 and 4, respectively, under the Globally Harmonized System. The aim of this study was to determine whether C40, C81, and a new compound, C4, act as euglycemic and antioxidant agents in male Wistar rats with streptozotocin-induced diabetes. The animals were randomly divided into six groups ( n = 7 ): the control, those with diabetes and untreated, and those with diabetes and treated with pioglitazone, C40, C81, or C4 (daily for 21 days). At the end of the experiment, tissue samples were collected to quantify the level of glucose, insulin, triglycerides, total cholesterol, and liver enzymes, as well as enzymatic and nonenzymatic antioxidant activity. C4, without a hypoglycemic effect, displayed the best antioxidant activity. Whereas C81 could only attenuate the elevated level of blood glucose, C40 generated euglycemia by the end of the treatment. All compounds produced a significant decrease in triglycerides.

The Study of Mixing Purple Sweet Potato and Turmeric Extract as Green Corrosion Inhibitor for API-5L in NaCl 3,5% Environment

Green inhibitors have become a major option for corrosion prevention since people are more aware of environmental damage. It is true that chemical inhibitors are more powerful at preventing corrosion, but its side effects are very harmful to the environment. Purple sweet potato (Ipomoea batatas L) in single use has been proven as an active inhibitor for certain applications. To improve this property, purple sweet potato is used as a mixed with other plants that contain antioxidant agents, such as ginger, melinjo, turmeric, jeera, etc. This paper discussed the effect of applying mixed extract of purple sweet potato with turmeric (Curcuma longa) as a green inhibitor to corrosion rate of API 5L steel in a 3.5% NaCl environment. Turmeric extract contains curcumin and kaempferol antioxidants while purple sweet potato extract contains antocyanin antioxidants. Corrosion rates were analyzed based on weight loss and polarization methods. The results showed the highest inhibitor efficiency was 82.54% achieved by 16 ml of turmeric mixed with 2 ml of purple sweet potato, and the optimum inhibitor efficiency was 74.2% achieved by 8 ml of turmeric mixed with 6 ml of purple sweet potato.

Solving the lignin waste crisis: Utilization of lignin to produce value- added antioxidant agents: حل أزمة نفايات اللجنين: استخدام اللجنين لإنتاج مضادات أكسدة ذات قيمة مضافة

Lignin is a major component of biomass that is considered a huge energy and carbon reserve. Aside from being the second most abundant polymer in nature, it is a major by- product of pulping, paper and other forestry- based industries with about 70 million tons per year. Due to it being highly biologically recalcitrant, lignin is underutilized and considered a waste product that is solely incinerated for power generation. Establishment of a market for lignin- based, value- added chemicals was a necessity. Because of its renewable nature, availability, and richness in phenolic component, however, it is considered as an attractive alternative for antioxidant activity. In our research, all types of extracted lignin exhibited a value ranging from 2.21 to 11.47 on the AAI assay suggesting high antioxidant activity. Furthermore, special chemical structures such as hydrogen atoms, double bonds between side chain carbons, as well as the presence of methoxyl groups can increase antioxidant activity by 2- 3 folds via means of radical scavenging. Finally, lignin extracted at higher temperature (~95C and greater) exhibited higher ORAC values compared to lignin extracted at lower temperature; ORAC values of 1072.32 to 3119.68 versus 1741.72 to 1745.11, respectively. This paper is going to shed more light on the lignin antioxidant properties, where it stems from, what affects it, as well as future directions and possible interdisciplinary potential improvement.

Evaluation of the phenolic compounds and the antioxidant potentials of Vitex agnus-castus L. leaves and fruits

Objectives In this study, we aim at deciphering the phenolic content of Vitex agnus-castus L. leaf and fruit extracts prepared with different methods and relate it to their antioxidant activity. Methods In this study, phenolic compounds and the antioxidant potential of the ethanol fruit and leaf extracts of V. agnus-castus L. (Chaste tree) were evaluated spectrometrically. Furthermore, selected polyphenols, i.e., chlorogenic acid and rutin, were determined by the HPLC-DAD method qualitatively and quantitatively. Results The results obtained from leaf and fruit extracts were compared with a commercial product (CP) containing the fruit extract of V. agnus-castus. Leaf extract was found to be richer in flavonoids when compared to the fruit counterparts. Accordingly, they also showed higher antioxidant activity. Conclusions Extracts prepared here can be considered as promising antioxidant agents for future therapeutic formulations.