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The corrosion behavior of copper in 0.1 M aqueous sulfuric acid medium has been studied using potentiodynamic polarization measurements, quantum chemical calculations, and molecular dynamic simulations in the presence and absence of (2E,5E)-2,5-dibenzylidenecyclopentanone (M1) and (2E,5E)-bis[(4-dimethylamino)benzylidene]cyclopentanone (M2). The compounds were freshly prepared in high yields via the Claisen–Schmidt reaction between the cyclopentanone and the corresponding aryl aldehyde. The results from the potentiodynamic measurements imply that M1 and M2 act as mixed inhibitors due to their adsorption on the copper surface. The more pronounced corrosion inhibition performance of the M2 molecule in comparison to M1 was related to the fact that this molecule contains two basic nitrogen atoms (in 4-dimethylamino group).

Background This study was undertaken to test the hypothesis that the newly synthesized curcuminoids B2BrBC and C66 supplementation will overcome hyperoxia‐induced tracheal hyperreactivity and impairment of relaxation of tracheal smooth muscle (TSM). Materials and methods Rat pups (P5) were exposed to hyperoxia (>95% O2) or normoxia for 7 days. At P12, tracheal cylinders were used to study in vitro contractile responses induced by methacholine (10−8–10−4M) or relaxation induced by electrical field stimulation (5–60 V) in the presence/absence of B2BrBC or C66, or to study the direct relaxant effects elicited by both analogs. Results Hyperoxia significantly increased contraction and decreased relaxation of TSM compared to normoxia controls. Presence of B2BrBC or C66 normalized both contractile and relaxant responses altered by hyperoxia. Both, curcuminoids directly induced dose‐dependent relaxation of preconstricted TSM. Supplementation of hyperoxic animals with B2BrBC or C66, significantly increased catalase activity. Lung TNF‐α was significantly increased in hyperoxia‐exposed animals. Both curcumin analogs attenuated increases in TNF‐α in hyperoxic animals. Conclusion We show that B2BrBC and C66 provide protection against adverse contractility and relaxant effect of hyperoxia on TSM, and whole lung inflammation. Both analogs induced direct relaxation of TSM. Through restoration of catalase activity in hyperoxia, we speculate that analogs are protective against hyperoxia‐induced tracheal hyperreactivity by augmenting H2O2 catabolism. Neonatal hyperoxia induces increased tracheal contractility, attenuates tracheal relaxation, diminishes lung antioxidant capacity, and increases lung inflammation, while monocarbonyl CUR analogs were protective of these adverse effects of hyperoxia. Analogs may be promising new therapies for neonatal hyperoxic airway and lung disease., This study was undertaken to test the hypothesis that the newly synthesized curcuminoids B2BrBC and C66 supplementation will overcome hyperoxia‐induced airway hyperreactivity and impairment of relaxation of tracheal smooth muscle.

To test the antioxidant properties of the newly synthesized (2E,6E)-2,6-bis(2-bromobenzylidene)cyclohexanone (B2BrBC) in parallel with C66 in rats with cardiac hypertrophy.The protective effects of both C66 and B2BrBC against oxidative stress in rats with cardiac hypertrophy, was studied by evaluating the activity of antioxidant enzymes, the relationship between the ratio of the activities of the antioxidant enzymes R = SOD/(GPx + CAT) and levels of thiols and lipid peroxidation in the heart. In order to gain better understanding of the antioxidant properties of the studied compounds, computational methods were utilized. The properties of selected structurally related derivatives were obtained on optimized geometries for ground states, using semi-empirical PM3 quantum mechanical calculations.The ratio R shows disequilibrium in rats with induced hypertrophy (p 0.001). Coextending changes were detected in total and free sulfhydryl group content (p = 0.011 for t-SH and p = 0.008, for free SH, respectively). The results with the B2BrBC, indicated strong thiol prevention reflected in the levels of both t-SH and f-SH. Taking into account the HOMO energies of B2BrBC (-9.398 eV) and C66 (-9.667), it can be concluded that B2BrBC has lower HOMO energy, which makes it a better electron donor and a better antioxidant.The obtained results indicated that the antioxidant ability of B2BrBC is positively associated with the catalytic SOD and GPx activities expressed through preserved t-SH levels. It seems plausible that for a compound to exhibit antioxidant activity, as most of the 2,6-bis(benzylidene)cyclohexanones do, they should be good electron donors.Understanding the relationship between cardiac hypertrophy induced oxidative injuries and supporters of endogenous reparatory machinery will help in establishing the beneficial role of adequate antioxidant supplementation. In this study reliable data on the preventive effects of newly synthesized symmetric monocarbonyl curcumin analogue B2BrBC and its role in the prevention of oxidative injuries on three levels (enzymatic, protein and lipid), in the heart hypertrophic onset, were obtained.

Thebaine is naturally occurring alkaloid which is of great importance in the pharmaceutical industry and up to now there is not a Pharmacopoeial monograph for this compound. There is a definite need for development of simple procedures for routine quality assessment based on physical and spectroscopic properties (melting point, UV-Vis, IR, specific optical rotation) and even more importantly a need for development of chromatographic methods for determination of purity.The main objective of this work was to develop RP-HPLC-UVD method for quantification of thebaine and also to develop complementary GC-MS method for qualitative analysis. The developed HPLC method utilized RP-C18 monolithic column, gradient elution with trifluoroacetic acid and formic acid in water and in acetonitrile and detection at 285nm. The effects of the relevant chromatographic conditions was investigated and the optimized and validated method was usеd for analysis of three batches of thebaine. A procedure that contained different methods for determination and identification of thebaine, was performed with main focus on the HPLC method suitable for quantitative and qualitative determination. In parallel, to complete the purity profile, the three batches of thebaine were analyzed by IR, UV-Vis spectroscopy and specific optical rotation and melting point determination. The analysis of thebaine can be performed in few steps by simple and reproducible methods like IR spectroscopy, specific optical rotation, melting point and the developed HPLC method, later proved by its validation. The developed HPLC-UV method is suitable for transfer to HPLC-MS method. The GC-MS method is quite suited for identification of thebaine and of the impurities, but is limited to free bases. Additionally, pseduomorphine and N-oxide derivatives of the related alkaloids are not suitable for GC-MS analysis.

A variety of benzamidomethyl derivatives were prepared in water under alkaline conditions (pH>9) via reaction of (benzamidomethyl)triethylammonium chloride (1) with different inorganic nucleophiles. Reaction of 1 with hydroxylamine did not give the expected mono(benzamidomethyl)-hydroxylamine (3) but rather gave N,N- di(benzamidomethyl)hydroxylamine (2). Reactions of 1 with sodium azide and potassium cyanide gave benzamidomethyl azide (4a) and benzamidomethyl cyanide (4b) respectively. Potassium thiocyanate and sodium iodide reacted with 1, and the anion- exchanged products (benzamidomethyl)triethylammonium isothiocyanate (5a) and (benzamidomethyl)triethylammonium iodide (5b) were thus obtained. Cyanamide and potassium cyanate reacted readily with 1 and both gave the same mixture of di(benzamidomethyl)amine (7) and tri(benzamidomethyl)amine (8). All the reactions occurred smoothly, under mild conditions, to give the products in moderate to high yields.

Two extraction methods for subsequent gas chromatographic (GC) determination of volatiles from freshly harvested and aged fennel fruit samples ( Foeniculum vulgare Mill.,ssp. vulgare var. dulce) have been compared. Hydrodistillation followed by GC-FID and GC-MS analysis was used as a standard method for essential oil characterization, while static headspace followed by GC (SHS-GC-FID) was used as a comparative method for determination of volatile components. As the fennel fruit ages, there is a gradual loss of the volatile components as indicated by the lower yield of essential oil and lower content of volatiles, as indicated by the alternative SHS-GC-FID analysis. Slight differences observed for the main components ( trans-anethole, estragole, fenchone, and limonene) using the two methods are negligible, indicating that these volatiles did not undergo chemical transformation during the sample preparation procedures. A difference in anisaldehyde content was observed when the composition of the hydrodistilled essential oil was compared with the SHS-GC-FIDanalysis of volatiles and explanation for the variation of anisaldehyde content and the origin of other compounds was suggested. Comparison of the obtained results showed that limonene oxides, carvone and carveolare detectable in SHS-GC-FID analysis of the aged fennel fruits, while in hydrodistilled samples analyzed by GC-FID they were not present. Another observed difference was the appearance of products in significant amounts with higher retention times than trans-anethole, namely threo- and erythro-anethole β-hydroxymethylether and anethole glycol that are not detectable in the essential oil obtained by hydrodistillation. So, the relative abundance of the major components is comparable between these two methods for fennel seed up to 3 years from harvest and they can be used interchangeably depending on the purpose and amount of material. Furthermore, SHS-GC-FID can be used for assessment of maximum storage time and quality of fennel fruit suitable for human consumption.

A new sulfide, 2-methyl-7-(phenylsulfanylmethyl)naphthalene was synthesized and its MS, IR, 1H NMR, 13C NMR and DEPT-135 data are reported.

Cultivated and wild growing samples of fennel ( Foeniculum vulgare Mill., Apiaceae) from R. Macedonia were studied for their volatiles and fatty acid composition. The main essential oil components isolated via hydrodistillation were: trans-anethole (>80%), estragole (

via the corresponding known alcohol 2-hydroxymethyl-7-methylnaphthalene [2]. Treatment of the alcohol with the Olah’s reagent (HF/pyridine) [3], according to the procedure of Olah and co-workers for fluorination of alcohols [4] did not result in the desired fluoride. The alternative strategy was to employ halogen exchange using the bromo derivative

In connection with our investigation of the competitive mesolytic cleavages [1] of radical anions we have prepared several symmetrically substituted 2,7-bis(halomethyl)naphthalene derivatives.[...]