Synthesis and antimicrobial and pharmacological properties of new thiosemicarbazide and 1,2,4‐triazole derivatives

Reaction of 4‐phenyl‐4H‐1,2,4‐triazole‐3‐thione with ethyl bromoacetate has led to the formation of ethyl [(4‐phenyl‐4H‐1,2,4‐triazol‐3‐yl)sulfanyl]acetate 1 , the structure of which was confirmed by X‐ray analysis. In the next reaction with 80% hydrazide hydrate, appropriate hydrazide 2 was obtained, which in reaction with isothiocyanates was converted to new acyl derivatives of thiosemicarbazides 2 , 3 , 3a , 3b , 3c , 3d , 3e , 3f , 3g , 3h . The cyclization of these compounds in alkaline media has led to formation of new derivatives of 5‐{[(4‐phenyl‐4H‐1,2,4‐triazole‐3‐yl)sulfanyl]methyl}‐4H‐1,2,4‐triazole‐3(2H)‐thiones 4a , 4b , 4c , 4d , 4e , 4f , 4g , 4j . The structure of the compounds was confirmed by elementary analysis and IR, ¹H‐NMR, ¹³C‐NMR, and MS spectra. Compounds 2 , 3 , 3a , 3b , 3c , 3d , 3e , 3f , 3g , 3h and 4a , 4b , 4c , 4d , 4e , 4f , 4g were screened for their antimicrobial activities, and the influence of the compounds 4a , 4b , and 4e , 4f , 4g on the central nervous system of mice in behavioral tests was examined. J. Heterocyclic Chem., (2011).     

The Ethylbenzene/Styrene Preferential Separation with Ionic Liquids in Liquid–Liquid Extraction

The objective of this work was to explore the feasibility of using ionic liquids (ILs), namely N-ethyl-N-methylmorpholinium dicyanamide, [EMMor][DCA], (3-hydroxypropyl)-1-methylmorpholinium dicyanamide, [N-C₃OHMMor][DCA], 1-(3-hydroxypropyl)-3-methylimidazolium dicyanamide, [N-C₃OHMIM][DCA], 1-(3-hydroxypropyl)pyridinium dicyanamide, [N-C₃OHPy][DCA], (3-cyanopropyl)pyridinium dicyanamide, [N-C₃CNPy][DCA], and (3-cyanopropyl)methylpyrrolidinium dicyanamide, [N-C₃CNMPyr][DCA] for the separation of ethylbenzene and styrene. The liquid–liquid equilibrium (LLE) data in ternary systems of {IL (1)?+?styrene (2)?+?ethylbenzene (3)} at T?=?298.15 K and ambient pressure is presented for the six ILs synthesized by us. The final chromatography analysis of the composition of tie-lines has shown that the studied ILs are not found in the raffinate phase and they show interesting results on the selectivity and solute distribution ratio for styrene extraction. A comparison of different ILs is presented for the studied separation problem. It was observed that the best separation selectivities were found for [N-C₃CNPy][DCA] (S_Av?=?2.38) and [N-C₃OHMMor][DCA] (S_Av?=?2.42) in comparison with other studied ILs in this work and those presented in the literature. While the data presented here are useful from a theoretical standpoint, the possibility of applications for these ILs in technological processes is questionable because of low solute distribution ratios, especially those calculated from the masses [N-C₃CNPy][DCA] (β_MAv?=?0.08) and [N-C₃OHMMor][DCA] (β_MAv?=?0.07). The experimental tie-lines were correlated with the non-random two liquid NRTL model.     

Cardiopulmonary resonance at 0.1 Hz demonstrated by averaged Lomb-Scargle periodogram

We demonstrate the resonant-like behaviour of the cardiopulmonary system in healthy people occurring at the natural low frequency oscillations of 0.1 Hz, which are often visible in the continuous pressure waveform. These oscillations represent the spontaneous oscillatory activity of the vasomotor centre and are sometimes called the Mayer waves. These 10-second rhythms probably couple with forced breathing at the same frequency and cause the observed cardiopulmonary resonance phenomenon. We develop a new method to study this phenomenon, namely the averaged Lomb-Scargle periodogram method, which is shown to be very effective in enhancing common frequencies in a group of different time series and suppressing those which vary between datasets. Using this method we show that in cardiopulmonary resonance the cardiopulmonary system behaves in a very similar way to a simple mechanical or electrical oscillator, i.e. becomes highly regular and its averaged spectrum exhibits a clear dominant peak and harmonics. If the forcing frequency is higher than 0.1 Hz, the total power and the share of power in the dominant peak and harmonics are lower and the prominence of the dominant peak and its harmonics greatly diminishes. It is shown that the power contributions from different forcing frequencies follow the resonance curve.     

(2,2′‐Bipyridine)bis(tri‐tert‐butoxysilanethiolato‐κS)lead(II) and (4,7‐diphenyl‐1,10‐phenanthroline‐κ2N,N′)bis(tri‐tert‐butoxysilanethiolato‐κS)lead(II) benzene hemisolvate

In the title mononuclear lead silanethiolates, [Pb(C₁₂H₂₇O₃SSi)₂(C₁₀H₈N₂)], (I), and [Pb(C₁₂H₂₇O₃SSi)₂(C₂₄H₁₆N₂)]·0.5C₆H₆, (II), the Pb atom shows a distorted square‐pyramidal coordination with a PbON₂S₂ core in which one S atom lies in an axial position. Intermolecular π–π and C—H...π interactions stabilize the structures. The benzene solvent molecule in (II) lies on an inversion centre.     

A Mild Deoxygenation of Heteroaromatic N-Oxides by Formamidinesulfinic Acid

Summary.  Various heteroaromatic N-oxides were efficiently deoxygenated to the corresponding bases under mild conditions using formamidinesulfinic acid (thiourea S,S-dioxide). Received March 24, 2000. Accepted April 18, 2000     

Bioaccessibility of Antioxidants in Blackcurrant Juice after Treatment Using Supercritical Carbon Dioxide

Blackcurrant juice (Ribes nigrum L.) was subjected to supercritical carbon dioxide (SCCD) at 10, 30, and 60 MPa for 10 min at 45 °C, as well as thermally treated at 45 and 85 °C for 10 min to determine the stability, antioxidant capacity (AC), and bioaccessibility (BAc) of vitamin C, total anthocyanins, and their individual monomers. An in vitro gastrointestinal digestion model completed with dialysis was used to assess BAc. The use of SCCD at each of the pressures applied improved the stability of vitamin C, total anthocyanins, and AC before in vitro digestion. As a result of digestion, the total content of vitamin C, anthocyanins, and AC decreased. The highest BAc of vitamin C was noted in fresh juice (FJ) (40%) and after mild heat treatment at 45 °C (T45) (46%). The highest BAc of total anthocyanins was also noted in the FJ (4.4%). The positive effect of the application of SCCD on the BAc of the delphinidin-3-O-glycosides was observed compared to T45 and thermal pasteurization at 85 °C (T85). Although SCCD did not significantly improve the BAc of vitamin C and total anthocyanins, the higher AC of SCCD samples after intestinal digestion (ABTS+• and DPPH•) and in dialysate (ABTS+•) compared to thermally treated was observed. The protocatechuic acid was detected by UPLC-PDA-MS/MS as the major metabolite formed during the digestion of delphinidin-3-O-rutinoside. This may indicate the influence of SCCD on improvement of the accessibility of antioxidants for digestion, thanks to which more metabolites with high antioxidant activity were released.     

Isotropic models for a heat transfer in periodic composites

A macroscopic model for the non – stationary heat transfer processes in a periodic honeycomb – type anisotropic rigid conductor is formulated. The main aim of this contribution is to show that the macroscopic properties of this conductor are isotropic. (© 2004 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)     

Pasta Enriched with Dried and Powdered Leek: Physicochemical Properties and Changes during Cooking

Food enrichment is commonly applied to increase the pro-health and dietary value of final products. This study aimed to evaluate how green leek powder (GL) added to semolina influenced the physicochemical, sensory, and cooking characteristics of the pasta. The pasta was prepared by partially substituting semolina with 0, 1, 2, 3, 4, and 5 g/100 g of GL. Then, the pasta samples were assessed for color, cooking properties, sensory features, mechanical properties, total phenolic content (TPC), and antioxidant activity (AA). The results indicated that GL significantly decreased the lightness and increased the yellowness of cooked pasta. The total color difference between the control pasta and enriched pasta samples ranged from 2.54 to 6.89 and 5.60 to 11.06 (for uncooked and cooked pasta, respectively). The addition of GL also caused an increase in the optimal cooking time and cooking loss. Moreover, a significant increase in stretching force was observed in cooked pasta. Sensory evaluation revealed that substitution of semolina with up to 2 g/100 g GL did not affect the smell, taste, and color of pasta. Most importantly, GL-enriched pasta was characterized by higher TPC and higher AA compared to the control samples. In summary, our results recommend partial replacement of semolina by GL (up to 3 g/100 g) in pasta production.     

Study on the Incorporation of Oat and Yeast β-Glucan into Shortbread Biscuits as a Basis for Designing Healthier and High Quality Food Products

According to international health and food organizations and authorities, people should limit fat intake since fat is the most caloric component of food and it is often a source of unsafe saturated fatty acids (FA) and trans isomers. The greatest health benefits come from replacing shorts with dietary fiber molecules. The aim of the study was to determine the possibility of reducing shortening content, which has an undesirable profile of FA, by addition of β-glucan molecules in shortbread biscuits. The effect of oat and yeast β-glucan supplementation on physical and sensory quality of products with reduced fat content (max 15%) were studied. It was shown that the substitution of shortening by β-glucan in shortbread biscuits is possible to a limited extent. Reduction in product energy value (up to 36 kcal/100 g) and content of undesirable FA (maximum 2.1 g/100 g) and increased of β-glucan content, regardless of the type, caused deterioration of biscuits quality and affected changes during storage. The substitution of shortening by β-glucan in food is a good way to improve nutritional value by increasing the amount of dietary fiber molecules, reducing calories, and amount of SFA in diets.