Classical and Advanced Chemical Sciences
Series of thiophene, thiazole, and pyrimidine derivatives based on the ethyl 2-amino-4,5,6,7-tetrahydrobenzo[b]thiophene-3-carboxylate starting material were synthesized, and cytotoxic activity of synthesized compounds was evaluated. Results showed that three compounds, viz. (2)-2-(4-methyl-3-phenylthiazole-2(3H)-ylidenea-mino)-4,5,6,7-tetrahydrobenzo[b]thiophene-3-carbonitrile, ethyl 2-(6-amino-4-imino-3-phenyl-2-thioxo-3,4-dihydropyrimidin-1(2H)-yl)-4,5,6,7-tetrahydrobenzo[b]thiophene-3-carboxylate, and 4-imino-3-phenyl-3,4,5,6,7,8-hexahydrobenzo[4,5]-thieno[2,3-d]pyrimidine-2-thiol, were the most active towards MCF-7 (breast adenocarcinoma), NCI-H460 (non-small cell lung cancer), and SF-268 (CNS cancer), but they were not active towards normal fibroblasts human cell line (WI-38). The toxicity of selected compounds against shrimp larvae was also studied.
Keywords: Tetrahydrobenzo[b]thiophene, thiazole, pyrimidine, thieno[d]pyrimidine, cytotoxic activity.
The ketonic compound (1) is synthesized from equal moles of morpholine, 4-nitrobenzaldehyde, and 3-nitro acetophenone. Schiff base compounds (2)-(4), prepared by reacting (1) with different aromatic amines (4-aminoantipyrine, p-phenylenediamine, 2-aminopyridine), contain a set of one or more of azomethine (-C=N-) groups that have been used in the preparation of many heterocyclic compounds, which when reacted with maleic anhydride give 1,3-oxazepine compounds (a ring with seven atoms) (5)-(7), and seven membered ring benzo[1,3]oxazepine compounds (8)-(10) are obtained by reaction with phthalic anhydride. The synthesized compounds are identified using physical (melting points, colour change, thin layer chromatography) and spectral methods such as IR, UV, and NMR spectra). The biological effectiveness of some of the prepared compounds is measured.
Keywords: Mannich bases, Schiff bases, oxazepines; benzo[1,3]oxazepines
A new series of Co(II), Ni(II), Cu(II) and Zn(II) complexes with a Schiff base derived from 4-amino-3-mercapto-5-oxo-1,2,4-triazine and 2,4-dichlorobenzaldehyde have been synthesized and characterized by spectroscopic studies. The coordination possibility of the Schiff base towards the metal ions have been determined by analytical, spectral (IR, 1H NMR, electronic spectroscopy, fluorescence, ESR) and thermal techniques. IR and thermal data support the presence of coordinated water in the metal complexes. The low molar conductance values in DMF indicate the non-electrolytic nature of the metal complexes. All the synthesized metal complexes show enhancement in fluorescence intensity in comparison to the ligand. The cyclic voltammetric studies of the Co(II), Ni(II) and Cu(II) complexes suggested the single electron transfer quasi-reversible nature of the complexes. Antimicrobial studies of the ligand and its metal complexes have been carried out in vitro against gram positive (S. aureus, B. subtilis), gram negative bacteria (E. coli, P. aeruginosa) and yeasts (S. cerevisiae, C. albicans).
Keywords: 1,2,4-triazine, Schiff base, metal complexes, fluorescence, antimicrobial activity
Materials and Environmental Chemistry
The radical copolymerization of 2-(4-vinylphenyl)cyclopropylmethyl cinnamate with glycidyl methacrylate has been studied and new cyclopropane- and epoxy-group containing photosensitive copolymers have been prepared. The relative activity of monomers and the parameters of Q and e by Alfrey and Price method have been determined. The copolymerization constants of 2-(4-vinylphenyl)cyclopropylmethyl cinnamate (r1) and glycidyl methacrylate (r2) were determined by the Fineman-Ross method and proved to be r1 = 1.05 and r2 = 0.4, respectively; the parameters Q1 and e1 were found to be 1.82, -0.79, respectively. The composition and structure of this copolymer have been established. The photochemical investigations of the synthesized copolymer have been carried out. It has been established that during the photochemical transformation a re-structuring takes place due to cyclopropane and epoxide ring opening and reaction of double bond in cinnamate fragment as well.
Keywords: microstructure; monomers; copolymerisation; 2-(4-vinylphenyl)cyclopropylmethyl cinnamate; photosensitivity
The efficiency of polyaniline/Fe3O4 (PANI/Fe3O4) nanocomposite (NC) as an adsorbent was investigated in the removal of Titan yellow (TY) dye from aqueous solution. The PANI/Fe3O4 was synthesized by polymerization of aniline in H2SO4 medium in the presence of Fe3O4 nanoparticles with ammonium persulfate as an oxidant. The NC formed was characterized by SEM and FT-IR methods. The dye removal process was studied under various conditions and was found that the adsorption activity of the PANI/Fe3O4 NC was greater than that of the bare PANI and Fe3O4 nanoparticles. Adsorption kinetics fitted with pseudo-first-order kinetic model.
Keywords: Adsorption, Magnetite, Polyaniline nancomposites, Titan yellow, wastewater treatment, dye removal
Chemical and Biological Aspects of Life
The biochemical composition of highbush blueberry fruit of 6 cultivars with different ripening periods, introduced in Belarus, is investigated on 14 indicators thrice a month at equal intervals. The nutrient and vitamin value of the fruit gradually decreased with the increasing amount of the dry matter, during storage, due to the depletion of free organic, ascorbic and phenol carboxylic acids, soluble sugars, pectic substances, tanning agents, anthocyanin pigments, catechins and flavonols. The transformation of the biochemical composition of the fruit, during storage, is strongly dependent on weather conditions of the season, rather than on their ripening period.
Keywords: Vaccinium corymbosum, highbush blueberry, berries, storage, biochemical composition
Nowadays, diseases associated with lipid accumulation in the human body such as obesity are becoming very important health issues. The aim of this study is to evaluate the impact of cafeteria diet feeding by Wistar rats, used as an experimental model of nutritional obesity, during 8 weeks, on lipid metabolism. Thus, we determined the levels of total cholesterol (TC) and triglycerides (TG) in plasma, lipoproteins and organs (liver, adipose tissue, muscle), and the activities of lipoprotein lipase (LPL) in organs, and hormone-sensitive lipase (HSL). The results show that cafeteria diet causes increased accumulation of lipids in adipose tissue leads to obesity with ectopic accumulation of lipids in other organs as liver, and induce lipoproteins metabolic disorders. Our results also show a disruption in the pathway of lipid storage enzyme (LPL) and lipid mobilization enzyme (HSL). Cafeteria diet is not only a primary risk for obesity, but also acts indirectly by adversely affecting other primary risk factors to serious chronic disease.
Keywords: cafeteria diet, obesity, lipids, lipoproteins, lipase activities
The system of microcirculation is the first link that is involved in pathological process at different extremely situations. Stress is followed with disturbance of microcirculation, development of organs' hypoxia and oxidative stress. The aim of this study is to show the type of angiogenesis in liver and brain under the influence of chronic variable physical stressors. In this study the influence of different stressors such as forced swimming inhalation, restraint stress, cold stress, orthostatic shock and food deprivation on the microcirculatory stream of liver and brain was observed. Investigation of sections of liver and brain yielded proof of changes of microvessels on chronic stress (CS). Thus CS influences a reorganization of blood vessels of liver and brain and it causes angiogenesis of lever sinusoids and brain capillaries.
Keywords: Chronic stress, liver, brain, blood vessel, sprouting and intussusception angiogenesis