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Polybrominated diphenyl ethers (PBDE) are a group of flame retardants used in a variety of artificial materials. Despite being phased out in most industrial countries, they remain in the environment and human tissues due to their persistence, lipophilicity, and bioaccumulation. Populational and experimental studies demonstrate the male reproductive toxicity of PBDEs including increased incidence of genital malformations (hypospadias and cryptorchidism), altered weight of testes and other reproductive tissues, altered testes histology and transcriptome, decreased sperm production and sperm quality, altered epigenetic regulation of developmental genes in spermatozoa, and altered secretion of reproductive hormones. A broad range of mechanistic hypotheses of PBDE reproductive toxicity has been suggested. Among these hypotheses, oxidative stress, the disruption of estrogenic signaling, and mitochondria disruption are affected by PBDE concentrations much higher than concentrations found in human tissues, making them unlikely links between exposures and adverse reproductive outcomes in the general population. Robust evidence suggests that at environmentally relevant doses, PBDEs and their metabolites may affect male reproductive health via mechanisms including AR antagonism and the disruption of a complex network of metabolic signaling.

Metformin is a first-line drug for DM2 treatment and prevention, but its complex effect on impaired glucose tolerance (IGT), including its influence on myocardial resistance to ischemia-reperfusion injury, is not completely studied. We aimed to evaluate the influence of metformin on the intestinal microbiota (IM), metabolism, and functional and morphological characteristics of myocardium in rats with IGT. IGT was modelled in SPF Wistar rats with a high-fat diet and streptozotocin and nicotinamide injection. Rats were divided into three groups: IGT (without treatment), IGT MET (metformin therapy), and CRL (without IGT induction and treatment). IGT group was characterized by: higher body weight, increased serum glucose and total cholesterol levels, atherogenic coefficient, impairment in the functional parameters of the isolated heart during perfusion, and larger myocardium infarction (MI) size in comparison with the CRL group. IM of IGT rats differed from that of CRL: an increase of Bacteroides, Acinetobacter, Akkermansia, Roseburia, and a decrease of Lactobacillus genera representation. Metformin therapy led to the diminishing of metabolic syndrome (MS) symptoms, which correlated with IM restoration, especially with the growth of Akkermansia spp. and decline of Roseburia populations and their influence on other members of IM. The obtained results allow us to consider from a new point of view the expediency of probiotic A. muciniphila use for MS treatment.

Pain is a common symptom that impairs the quality of life for people around the world. Local anesthetics widely used for pain relief have a number of side effects, which makes the development of both new drugs and new ways to control their activity particularly important. Photopharmacology makes it possible to reduce the side effects of an anesthetic and control its biological activity in the body. The purpose of this work was to create a new light-controlled local anesthetic and study its biological activity in animals. A compound with a simple scheme of synthesis was chosen to shift the UV-Vis absorption band towards the visible range of the spectrum and was synthesized for the first time. Some computer calculations were performed to make sure that the aforementioned changes would not lead to loss of biological activity. The micellar form of the new compound was prepared, and in vivo biological studies were carried out in rabbits. The existence of a local anesthetic effect, which disappeared almost completely on irradiation with light (λ = 395 nm), was shown using the surface anesthesia model. Moreover, the possibility of multiple reversible changes in the biological activity of ethercaine under the action of light was demonstrated. The latter compound manifests no local irritating effect, either. The data obtained indicate the prospects for the development of new compounds based on azobenzene for light-controlled local anesthesia.

Expression analysis of small noncoding RNA (sRNA), including microRNA, piwi-interacting RNA, small rRNA-derived RNA, and tRNA-derived small RNA, is a novel and quickly developing field. Despite a range of proposed approaches, selecting and adapting a particular pipeline for transcriptomic analysis of sRNA remains a challenge. This paper focuses on the identification of the optimal pipeline configurations for each step of human sRNA analysis, including reads trimming, filtering, mapping, transcript abundance quantification and differential expression analysis. Based on our study, we suggest the following parameters for analysis of human sRNA in relation to categorical analyses with two groups of biosamples: (1) trimming with the lower length bound = 15 and the upper length bound = \(Read\ length - 40\% Adapter\ length\); (2) mapping on a reference genome with bowtie aligner with one mismatch allowed (-v 1 parameter); (3) filtering by mean threshold > 5; and (4) analyzing differential expression with DESeq2 with adjusted p-value < 0.05 or limma with p-value < 0.05 if there is very little signal and few transcripts.

Severe outcomes of COVID-19 are associated with pathological response of the immune system to the SARS-CoV-2 infection. Emerging evidence suggests that interaction may exist between COVID-19 pathogenesis and a broad range of xenobiotics, resulting in significant increases in death rates in highly exposed populations. Therefore, a better understanding of the molecular basis of the interaction between SARS-CoV-2 infection and chemical exposures may open opportunities for better preventive and therapeutic interventions. We attempted to gain mechanistic knowledge on the interaction between SARS-CoV-2 infection and chemical exposures using in-silico approach, where we identified genes and molecular pathways affected by both chemical exposures and SARS-CoV-2 in human immune cells (T-cells, B-cells, NK-cells, dendritic, and monocyte cells). Our findings demonstrate for the first time that overlapping molecular mechanisms affected by a broad range of chemical exposures and COVID-19 are linked to IFN type I/II signaling pathways and the process of antigen presentation. Based on our data, we also predict that exposures to various chemical compounds will predominantly impact the population of monocytes during the response against COVID-19.

In this work, we obtained the first selenium-containing chlorin with a chalcogen atom in exlocycle E. It was shown that the spectral properties were preserved in the target compound and the stability increased at two different pH values, in comparison with the starting purpurin-18. The derivatives have sufficiently high fluorescence and singlet oxygen quantum yields. The photoinduced cytotoxicity of sulfur- and selenium-anhydrides of chlorin p6 studied for the first time in vitro on the S37 cell line was found to be two times higher that of purpurin-18 and purpurinimide studied previously. Moreover, the dark cytotoxicity increased four-fold in comparison with the latter compounds. Apparently, the increase in the dark cytotoxicity is due to the interaction of the pigments studied with sulfur- and selenium-containing endogenous intracellular compounds. Intracellular distributions of thioanhydride and selenoanhydride chlorin p6 in S37 cells were shown in cytoplasm by diffusion distribution. The intracellular concentration of the sulfur derivative turned out to be higher and, as a consequence, its photoinduced cytotoxicity was higher as well.

Nanotextured magnesium oxide (MgO) can exhibit both antibacterial and tissue regeneration activity, which makes it very useful for implant protection. To successfully combine these two properties, MgO needs to be processed within an appropriate carrier system that can keep MgO surface available for interactions with cells, slow down the conversion of MgO to the less active hydroxide and control MgO solubility. Here we present new composites with nanotextured MgO microrods embedded in different biodegradable polymer matrixes: poly-lactide-co-glycolide (PLGA), poly-lactide (PLA) and polycaprolactone (PCL). Relative to their hydrophilicity, polarity and degradability, the matrices were able to affect and control the structural and functional properties of the resulting composites in different manners. We found PLGA matrix the most effective in performing this task. The application of the nanotextured 1D morphology and the appropriate balancing of MgO/PLGA interphase interactions with optimal polymer degradation kinetics resulted in superior bactericidal activity of the composites against either planktonic E. coli or sessile S. epidermidis, S. aureus (multidrug resistant-MRSA) and three clinical strains isolated from implant-associated infections (S. aureus, E. coli and P. aeruginosa), while ensuring controllable release of magnesium ions and showing no harmful effects on red blood cells.

Advanced paternal age at fertilization is a risk factor for multiple disorders in offspring and may be linked to age-related epigenetic changes in the father&rsquo, s sperm. An understanding of aging-related epigenetic changes in sperm and environmental factors that modify such changes is needed. Here, we characterize changes in sperm small non-coding RNA (sncRNA) between young pubertal and mature rats. We also analyze the modification of these changes by exposure to environmental xenobiotic 2,2&prime, 4,4&prime, tetrabromodiphenyl ether (BDE-47). sncRNA libraries prepared from epididymal spermatozoa were sequenced and analyzed using DESeq 2. The distribution of small RNA fractions changed with age, with fractions mapping to rRNA and lncRNA decreasing and fractions mapping to tRNA and miRNA increasing. In total, 249 miRNA, 908 piRNA and 227 tRNA-derived RNA were differentially expressed (twofold change, false discovery rate (FDR) p &le, 0.05) between age groups in control animals. Differentially expressed miRNA and piRNA were enriched for protein-coding targets involved in development and metabolism, while piRNA were enriched for long terminal repeat (LTR) targets. BDE-47 accelerated age-dependent changes in sncRNA in younger animals, decelerated these changes in older animals and increased the variance in expression of all sncRNA. Our results indicate that the natural aging process has profound effects on sperm sncRNA profiles and this effect may be modified by environmental exposure.

Photodynamic therapy (PDT) is currently one of the most promising methods of cancer treatment. However, this method has some limitations, including a small depth of penetration into biological tissues, the low selectivity of accumulation, and hypoxia of the tumor tissues. These disadvantages can be overcome by combining PDT with other methods of treatment, such as radiation therapy, neutron capture therapy, chemotherapy, etc. In this work, potential drugs were obtained for the first time, the molecules of which contain both photodynamic and chemotherapeutic pharmacophores. A derivative of natural bacteriochlorophyll a with a tin IV complex, which has chemotherapeutic activity, acts as an agent for PDT. This work presents an original method for obtaining agents of combined action, the structure of which is confirmed by various physicochemical methods of analysis. The method of molecular modeling was used to investigate the binding of the proposed drugs to DNA. In vitro biological tests were carried out on several lines of tumor cells: Hela, A549, S37, MCF7, and PC-3. It was shown that the proposed conjugates of binary action for some cell lines had a dark cytotoxicity that was significantly higher (8–10 times) than the corresponding metal complexes of amino acids, which was explained by the targeted chemotherapeutic action of the tin (IV) complex due to chlorin. The greatest increase in efficiency relative to the initial dipropoxy-BPI was found for the conjugate with lysine as a chelator of the tin cation relative to cell lines, with the following results: S-37 increased 3-fold, MCF-7 3-fold, and Hela 2.4-fold. The intracellular distribution of the obtained agents was also studied by confocal microscopy and showed a diffuse granular distribution with predominant accumulation in the near nuclear region.

The review discusses the latest advances in the directed synthesis and application of macroheterocyclic compounds in science, engineering and technology, viz. as catalysts for various processes in photo- and electrocatalysis, optical chemosensors for metal cations, selective receptors of organic compounds, inductors and selectors, in nonlinear optics, organic electronics, as magnets, photosensitizers for PDT of a number of oncological diseases and for antimicrobial PDT, etc.

Alzheimer&rsquo, s disease (AD) is the commonest type of late-life dementia and damages the cerebral cortex, a vulnerable brain region implicated in memory, emotion, cognition, and decision-making behavior. AD is characterized by progressive neuronal loss, but the mechanisms of cell death at different stages of the disease remain unknown. Here, by means of OXYS rats as an appropriate model of the most common (sporadic) AD form, we studied the main pathways of cell death during development of AD-like pathology, including the preclinical stage. We found that apoptosis is activated at the pre-symptomatic stage (age 20 days) correlating with the retardation of brain development in the OXYS strain early in life. Progression of the AD-like pathology was accompanied by activation of apoptosis and necroptosis resulting from a decline of autophagy-mediated proteostasis. Our results are consistent with the idea that the nature of changes in the pathways of apoptosis, autophagy, and necrosis depends on the stage of AD.

Fluorinated polystyrene has a number of attractive properties, but its synthesis is rather complicated. In this regard, it seems attractive to obtain polyfluorstyrene by direct fluorination of polystyrene under "mild" conditions – in the form of a suspension in a perfluorinated liquid. The fluorinated polymer was characterized by IR and 19F and 13C solid-state NMR spectroscopy. It was shown that non-destructive hydrogen-substituting fluorination prevails under these “mild” conditions; fluorination occurs into the benzene ring and into the main carbon chain.

Inorganic tetramethylene bis-onium compounds were studied as reversible inhibitors of various cholinesterases (ChE), i.e., human erythrocyte acetyl-ChE, horse blood serum butyryl-ChE, grass frog Rana temporaria brain ChE, and Pacific squid Todarodes pacificus and commander squid Berryteuthis magister visual ganglia ChE from various habitats in the northwest Pacific Ocean, in order to study the influence of the nature of the onium atom on their anti-ChE activities. bis-Phosphonium inhibitors turned out to be significantly more potent effectors than bis-ammonium compounds, which may actually have been due to the significant increases of size and hydrophobicity of the onium groups. The bis-ammonium organosilicon compound and its monoammonium analog turned out to be equally active as reversible ChE inhibitors in mammals. The bis-phenyliodonium derivative was studied for the first 7time, was characterized by significantly increased hydrophobicity due to introduction of F atoms into the tetramethylene spacer in the onium chain, and exhibited marked anti-ChE activity with respect to mammalian ChE.

A novel method for rapid, quantitative determination of trace permanent gases and carbon dioxide in ultra-high purity ammonia by dual-channel two-dimensional GC-PDHID is presented. An improved matrix back-flush-to-vent approach combining back-flush column switching technique with auxiliary NaHSO4 ammonia trap is described. The NaHSO4 trap prevents traces of ammonia from entering the analytical column and is shown not to affect the impurity content of the sample. The approach allows shortening the analysis time and increasing the amount of measurements without extensive maintenance of the GC-system. The performance of the configuration has been evaluated utilizing ammonia- and helium-based calibration standards. The method has been applied for the analysis of 99.9999+% ammonia purified by high-pressure distillation at the production site.

Progesterone membrane receptor component 1 (Pgrmc1) is a cytochrome b5-related protein with wide-ranging functions studied most extensively in non-neural tissues. We previously demonstrated that Pgrmc1 is widely distributed in the brain with highest expression in the limbic system. To determine Pgrmc1 functions in cells of these regions, we compared transcriptomes of control siRNA-treated and Pgrmc1 siRNA-treated N42 hypothalamic cells using whole genome microarrays. Our bioinformatics analyses suggested that Pgrmc1 plays a role in immune functions and likely regulates proinflammatory cytokine signaling. In follow-up studies, we showed that one of these cytokines, TNFα, increased expression of rtp4, ifit3 and gbp4, genes found on microarrays to be among the most highly upregulated by Pgrmc1 depletion. Moreover, either Pgrmc1 depletion or treatment with the Pgrmc1 antagonist, AG-205, increased both basal and TNFα-induced expression of these genes in N42 cells. TNFα had no effect on levels of Rtp4, Ifit3 or Gbp4 mRNAs in mHippoE-18 hippocampal control cells, but Pgrmc1 knock-down dramatically increased basal and TNFα-stimulated expression of these genes. P4 had no effect on gbp4, ifit3 or rtp4 expression or on the ability of Pgrmc1 to inhibit TNFα induction of these genes. However, a majority of the top upstream regulators of Pgrmc1 target genes were related to synthesis or activity of steroids, including P4, that exert neuroprotective effects. In addition, one of the identified Pgrmc1 targets was Nr4a1, an orphan receptor important for the synthesis of most steroidogenic molecules. Our findings indicate that Pgrmc1 may exert neuroprotective effects by suppressing TNFα-induced neuroinflammation and by regulating neurosteroid synthesis.

Micrometer-sized structures consisting of TiO2 nanoparticles were prepared using the sol–gel technique in combination with the structure-directing agent triethanolamine (TEA). The interaction of the TEA with the hydrolyzed sol–gel products led to the formation of TEA titanate complexes, which then enabled the assembly of sol–gel-precipitated nanosized powders. A subsequent thermal treatment of these powders resulted in the formation of micrometer-sized structures consisting of TiO2 anatase and rutile nanoparticles. To characterize the prepared powders, FTIR spectroscopy, XRD analysis, the Brunauer-Emmett-Teller method (sBET), UV–Vis spectrometry and electron microscopy (FE-SEM, and TEM) were employed. The photocatalytic degradation of the azo dye known as methylene blue was monitored under UV and Vis irradiation and showed that the micrometer-sized structures consisting of TiO2 nanoparticles exhibited a similar photocatalytic activity to submicrometer-sized structures consisting of TiO2 nanoparticles prepared without TEA.

We have investigated the effect of oleic acid concentration on the physicochemical properties of solvothermally derived cobalt ferrite nanoparticles (CFO NPs). Without the oleic acid, agglomerated nanoplatelets with a crystallite size of about 19 nm were obtained, according to X-ray diffraction (XRD) and transmission electron microscopy (TEM). However, the addition of oleic acid decreases the size of the CFO NPs and at critical concentration, which was determined to be 0.25 M, well-dispersed, nonagglomerated spherical particles of about 6 nm were obtained. A further increase in the oleic acid concentration affected the particle size only slightly, with a relatively constant surface coverage of the oleic acid ligand. The results of our study indicate that particle-size control was achieved by bridging bidentate interactions between the oleic acid molecules and the metal atoms on the surface of the NPs, as determined by Fourier transform infrared spectra. These interactions affected the surface strain of NP...

The study was performed to check whether the horse blood serum butyrylcholinesterase expresses transferase activity in the presence of several low-molecular aliphatic alcohols, using chromogenic substrate 1-methyl-8-acetoxychinolium iodide whose phenolic hydrolysis product absorbs intensively at 445 nm, whereas the initial ester practically does not absorb within this spectrum area. This allowed measuring simultaneously accumulation of both products of enzymatic hydrolysis: of acetic acid by the potentiometric, while of phenol—by the colorimetric method. Rates of formation of both products of enzymatic hydrolysis are practically equal in experiments with all studied alcohols. This indicates that horse blood serum butyrylcholinesterase under these experimental conditions does not catalyze the transfer of acetyl residue to the studied aliphatic alcohols, i.e. does not have transferase activity.

There was studied action of aliphatic alcohols (ethanol, propanol, isopropanol, n-butanol, isobutanol, sec-butanol, tert-butanol), and pH on various kinds of serum cholinesterase. At inhibition of the cholinesterase hydrolytic activity under effect of alcohols the key role was played not by the total number of carbon atoms in the alcohol molecule, but by the “efficient length” of the carbohydrate chain. The fact that the presence of alcohols did not affect parameters of reversible inhibition of cholinesterase by onium ions tetramethylammonium and choline allows suggesting the absence of action of solvents on specific sorption of acetylcholine in the enzyme active center. With aid of two sets of hydrophobic organophosphorus inhibitors (OPI) (12 compounds), we have managed to estimate both the degree and the character itself of serum cholinesterase.

The gas-releasing reaction is the most important process in the preparation of foam glass. In this paper we investigated the gas-releasing reactions by means of thermogravimetry coupled with mass spectrometry. We used carbon (activated charcoal and carbon black) and/or manganese oxides (MnO2, Mn2O3, and Mn3O4) as the foaming additives. We show that manganese oxides have different functions in the foaming process. The thermal decomposition of MnO2 below the sintering temperature has a negative impact on the foaming process as it shifts the foaming to higher temperatures, increases the mass-loss rate, leading to open pores, and burns out the carbon. When foaming in an oxidizing atmosphere, the carbon is burnt out by the oxygen from the atmosphere. Instead, Mn2O3 can be used as the foaming agent in an oxidizing atmosphere. In the oxygen-free atmosphere, Mn3O4 can be used as the oxidizing agent, supporting the oxidation of carbon and the foaming process. The redox equilibrium of manganese (Mn2+/Mn3+), influenced by the oxygen partial pressure in the pores and physically dissolved oxygen in the glass, shows the strongest influence on the foaming process. The CO/CO2 ratio in the evolved gases depends on the carbon source and the temperature.

Chemical modification of potato carboxy starch in the sodium pyrosulfate—dimethyl sulfoxide system was studied with the aim of preparing water-soluble highly substituted sulfo esters. The dependence of the degree of sulfo group substitution on the reaction conditions was studied in detail. The optimal conditions ensuring formation of water-soluble sulfo esters of carboxy starch with the maximal sulfur content were determined. The carboxy starch sulfo ester samples synthesized were characterized by elemental analysis, IR and 13C NMR spectroscopy, and high-performance exclusion chromatography.

By means of high-performance liquid chromatography, spectrophotometry, and chemical analysis, it was found that UV absorption of γ-irradiated aqueous solutions of polyols, such as glycerol, inositol, and xylitol, is due to the presence of malonic dialdehyde (MDA) and other β-dicarbonyl radiolytic products in the form of ketols. The contribution of MDA to these spectra is determined by the structure of the initial polyol, the pH of the solvent, and the absorbed dose of irradiation. Mechanisms for the formation of the radiolysis products in question are proposed.

A series of organosilicontitanium (OST) glycerohydrogels with the general formula 2Si(C3H7O3)4 Ti(C3H7O3)4 xC3H8O3 yH2O (where 9 x 30 and 60 y 120) were synthesized and some of their pharmacological properties were studied. High percutaneous activity of the compounds was revealed by measuring the diffusion of sodium diclofenac through intact skin membranes in vitro. It was established that all of the synthesized substances are nontoxic. The wound-healing and antioxidant properties of the glycerohydrogels were studied. The experimental results show that OST glycerohydrogels can be recommended for further testing as effective percutaneous vehicles of medicines with wound-healing, burn-healing, and antioxidant action.

Reduction of carbonyl compounds with polyethylsiloxane in the presence of titanium alkoxides gives the corresponding alcohols in high yields.

A new way to utilize polychlorobiphenyls was suggested: transformation of Sovol base hydrolysis products into glycidyl ethers and titanates. The resulting products were tested as components of epoxy compounds which are subsequently cured to obtain three-dimensional polymer networks.

The previously unknown 4,11-dimethoxynaphtho[2,3-f]indazole-5,10-dione has been obtained by the thermal cyclization of N-nitroso derivative of 2-acetamido-3-methyl-1,4-dimethoxyanthraquinone.

The corresponding Mannich bases have been synthesized by the aminomethylation of 6-methyl-1H-pyrrolo[2,3-a]- and 4-methyl-3H-pyrrolo[3,2-c]phenanthridinium iodides. The interaction of 6-chloro-phenanthridine with indoline and with 5-amino-N-acetylindoline gave the corresponding derivatives of phenanthridine. 6-(1-Indolyl)phenanthridine has been obtained by the dehydrogenation of 6-(1-indolinyl)phenanthridine with manganese dioxide.

2-(Diphenylmethan-4-yl)- and 2-(dibenzyl-4-yl)indoles have been synthesized by the Fischer reaction. Reactions carried out included azo coupling, formylation, and nitrosation. The corresponding 3-substituted derivatives were obtained.

4,11-Dihydroxynaphtho[2,3-f]indole-5,10-dione (pyrroloquinizarin), its 11-dehydroxy derivative, and Mannich base were synthesized by demethylation of previously obtained methoxynaphtho[2,3-f]indole-5,10-diones.

A method has been developed for N-alkylating 3H-pyrrolo[2,3-c]phenothiazine 11,11-dioxide with alkyl chlorides in absolute dimethylformamide in the presence of sodium hydroxide.

A series of fluorogenic tetra-, penta-, and hexapeptide substrates of the general structure Abz-X-Phe-Phe-Y-Ded (or -pNa in place of -Ded), where X = Ala, Ala-Ala, or Val-Ala and Y = -, Ala, or Ala-Ala, were proposed. Kinetic parameters of hydrolysis of these substrates by pepsin, cathepsin D, human gastricsin, pig pepsin, calf chymosin, and aspergillopepsin A were determined. The compounds synthesized proved to be effective substrates for aspartyl proteases of diverse origins.

N-Acetylation and several N-alkylation reactions have been carried out for the previously synthesized 4,11-dimethoxynaphtho[2,3-f]indole-5,10-dione.

1H, 10H-benzo[e]pyrrolo[3,2-g]indole-2,9-dicarboxylic acid dichloride has been synthesized and condensed with amines and phenols to give the corresponding diamides and activated diesters. The mass spectra of the dichloride and several diamides have been investigated.

The course of the Vilsmeier acetylation of new heterocyclic systems, namely, indolo[4,5-d]-, indolo[6,5-d]-, indolo[5,6-d]-, indolo[5,4-d]benzo[b]furans, 3H-pyrrolo[2,3-c]carbazole, 3H-pyrrolo[2,3-c]pheno-thiazine 11,11-dioxide, and 3H-pyrrolo[2,3-c]acridine depends on the type of fusion of the pyrrole ring. Angular heterocycles are acetylated at the β-position of the pyrrole ring, while linear heterocycles under analogues conditions give dimerization products with a substituent at the nitrogen atom of the hydrogenated part of the dimer molecule. 3H-Pyrrolo[2,3-c]phenothiazine 11,11-dioxide and 3H-pyrrolo[2,3-c]acridine are not acetylated under Vilsmeier reaction conditions.

4,11-Dimethoxynaphtho[2,3-f]indole-5,10-dione and 4-methoxynaphtho[2,3-f[indole-5,10-dione have been synthesized by the Leimgruber-Batcho reaction from 1,4-dimethoxy-2-methyl-3-nitroanthraquinone.

The behavior of 3H-pyrrolo(2,3-c)phenoxathiin 11,1]-dioxide in electrophilic substitution reactions is similar to that of other indole derivatives. The corresponding 1-substituted compounds of pyrrolophenoxathiin dioxides have been obtained.

Cyclization of the 2 phenoxathiin 10,10-dioxide hydrazone of ethyl pyruvate in ethyl polyphosphate results in the concurrent formation of the respective cyclic esters of both angular and linear structures. The parent compounds of a new condensed heterocyclic system of pyrrolophenoxathiin dioxides are synthesized from the latter.

In this work we prepared TiO2 nano-powders and TiO2/Pt nano-composites via three synthesis methods (sol-precipitation, sonochemical method, hydrothermal method) starting with the same precursors and media. To evaluate and compare the physical properties of the prepared materials, X-ray diffraction analysis, BET measurements, FTIR spectroscopy, X-ray photoelectron spectroscopy (XPS) and electron microscopy (TEM, HRTEM, SAED) were applied. The results showed changes to the TiO2 phase composition and crystallinity, the specific surface area as well as the platinum’s particle shape and size, depending on the method of synthesis. To determine the photocatalytic efficiency of the prepared materials, the photocatalytic discoloration of the methylene blue solution was evaluated using UV–Vis spectroscopy. The important properties required for a high photocatalytic activity, related to the surface characteristics and the phase composition, were determined in terms of the synthesis method. It was concluded that the optimum characteristics were obtained when using the hydrothermal approach, where the TiO2 had two phases, i.e., – anatase and rutile, a Pt-phase in the form of nanoparticles and adsorbed Pt-molecular species, as well as the presence of available free surface hydroxyl groups. Such characteristics had a critical influence on the photocatalytic activity of the final material.

The methods of synthesis of isomeric pyrroloindoles are surveyed. The characteristic features of electrophilic substitution reaction of the pyrroloindole ring and certain side chain reactions are discussed. The bibliography includes 60 references.

New indole derivatives — 2-ethoxycarbonyl-5(p-acetylphenyl)indole andpara-substituted 2-diphenylindoles —key compounds for synthesis of new bisindoles, were synthesized from 4-acetyl-4′-nitrodiphenyl.