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The extensive pharmacological applications of the pyrazole-based compounds stimulated us to synthesize the highly functionalized, pyrazolylmalonyl diisothiocyanate derivative (2)via treating 2-((1,3-diphenyl-1H-pyrazol-4-yl)methylene)malonyl dichloride (1) with ammonium thiocyanate in acetonitrile at room temperature. The diisothiocyanate derivative 2 was subsequently conducted with a double molar ratio of different nitrogen nucleophiles like 4-acetylaniline, 2-aminobenzoic acid, 6-aminothiouracil, 2-aminothiadiazole derivative, hydrazine, phenylhydrazine, thiophene-2-carbohydrazide, 2-hydroxybenzohydrazide, 2-cyanoacetohydrazide, thiourea, thiosemicarbazide, 2-aminoaniline, and thiocarbohydrazide, aiming to construct some valuable heterocyclic systems. The synthesized compounds were screened for their insecticidal activity against healthy late third instar larvae P. interpunctella and Nilaparvata lugens and the results showed that pyrimidinethione, thiadiazolotriazine, and tetrazinethione derivatives exhibited the highest insecticidal potency that are supported by DFT stimulation and their molecular docking. [ABSTRACT FROM AUTHOR]

A new series of various N-(1-(2-chlorobenzo[h]quinolin-3-yl)-1-substituted-vin-2-yl)benzamide derivatives was designed and synthesized based on the 2-chlorobenzo[h]quinoline core as potential antioxidant and insecticidal agents. In vitro antioxidant activities of these compounds were evaluated and compared with commercial antioxidant (ascorbic acid). The results showed good antioxidant activities of these compounds. In addition, in vitro insecticidal activities revealed that most of these compounds exhibited high insecticidal activity against cotton leafworm compared with chlorpyrifos. Some compounds in these series were better than the commercial insecticidal, chlorpyrifos. [ABSTRACT FROM AUTHOR]

It was well known that hydrazine–hydrazone derivatives have an important role in different synthetic and medicinal fields. Therefore, the hydrazide–hydrazone derivative 3 was treated with electrophilic reagents achieving some quinoline-based heterocyclic systems such as chromene and pyridine derivatives and screened for their rodenticidal activity. The potent compounds were subjected to density functional theory studies. Seven compounds were tested for hemorrhoidal activity. Compounds 5, 6, and 7 were more effective against rodents than the other synthesized compounds, which were controlled by the most potent active second-generation products, such as chlorophacinone, brodifacoum, and warfarin. This could be attributed to their existence in more tautomeric structures. As a result, they could be used as rodenticides. [ABSTRACT FROM AUTHOR]

The broad spectrum of biological activity of pyrazole derivatives coupled with our interest in the chemistry of nitrogen heterocycles led us to synthesize a bis-benzoxazinone derivative bearing a pyrazole scaffold and utilize it as a key material for the construction of some bisimidazole, bistriazole, and bisbenzimidazole derivatives obtained by reactions with some mono- and bidentate nitrogen nucleophiles. The density functional theory studies of the synthesized compounds were calculated. The synthesized compounds were screened for their in vitro antitumor activity against two human tumor cell lines; HepG2 and MCF-7. Some compounds displayed satisfactory activities. [ABSTRACT FROM AUTHOR]

New series of compounds were prepared by replacing the lateral methyl and bromo substituents in the previously investigated 4-ring compounds by the strong electronegative and smaller size fluorine atom. The two wings of the rode-shaped molecules, one is a compact polar group (CH3O, CH3, H, and Br), while the other is an alkoxy group with varying chain length that varies between 6–16 carbon atoms. Transition temperatures and temperature ranges of the observed phases were determined by DSC and phases identified by PLM. Except for the terminally methoxy-substituted homologues, which were found to be purely nematogenic, homologues of all the remaining derivatives are dimorphic possessing both N and SmA phases with wide temperature range. The fluoro derivatives were compared with the previously investigated lateral Br and methyl analogues in order to evaluate the effect of the polarity and size of the lateral group on their mesomorphic behaviour and polarisability anisotropy (ΔαM). The comparison revealed that the replacement of lateral substituent by the small-sized strong electronegative fluorine atom is accompanied by an enhancement of thermal stability and temperature ranges of the mesophases compared with lateral Br and methyl substituents. The results were discussed in terms of molecular polarisability and steric effect. [ABSTRACT FROM AUTHOR]

The degradation and embrittlement of paper is due to the depolymerization of cellulose fibers; this is induced by acidity and oxidation. An important part of dealing with these chemically unstable materials is the neutralization of acid and deposition of a buffer reservoir to protect the fibers from introduction of acid in future. Paper deacidification is a fundamental process for achieving this goal. Any deacidification method chosen must be able to treat large numbers of items, safely, quickly and cheaply. The main goal of this paper was to investigate the effect of two deacidification solutions, which have never been used in Egypt, on the chemical and physical properties of different types of paper in order to find an alternative to Calcium hydroxide the most common deacidification method used in Egypt. Magnesium salts have been chosen to produce two deacidification methods, one of them in aqueous media, and the other in nonaqueous media; however, the magnesium has excellent deacidification properties and never have been applied in Egypt before. This paper is concerned with the Evaluation of Magnesium Bicarbonate (MBC) and Methyl Magnesium Carbonate (MMC), as neutralization agents, on the stability of paper substrate before and after accelerated ageing. Deacidification of acid paper samples (old book and newspaper) coming from wood pulp (20 century) and whatman paper samples, has been carried out with elaborate findings. Examinations and scientific analyses have been used in the assessment of treated samples, to figure out the efficacy of the two methods on the paper stability. Both methods have adequate deacidification properties; the pH value of paper has increased after deacidification. Mechanical testing and Fourier-transform infrared spectroscopy (FTIR) have proven considerable stability of mechanical and chemical properties of deacidified paper after accelerated ageing. [ABSTRACT FROM AUTHOR]

Several binary systems made from two laterally substituted azo/ester isomers, namely 2"- (and 3"-) methyl-4-substituted phenyl 4'-(4"-alkoxyphenylazo) benzoates, where the length of the terminal alkoxy group = 8 and 16 carbons, while the other terminal substituent, X, varies between CH3O, CH3, H, Br and CN groups, were investigated using differential scanning calorimetry (DSC) and phases identified by polarised light microscope (PLM). For the sake of comparison, two another binary systems made from 2"- (or 3"-) methyl-4-substituted phenyl 4'-(4"-alkoxyphenylazo) benzoates (n = 8 and X = CH3) each was mixed with its laterally neat analogue and similarly investigated. Results were discussed on the basis of constructed phase diagrams whereby various mesomorphic properties were observed dependent on X, n, and position of the lateral methyl group. In most of the cases, the mixtures exhibited eutectic compositions, while linear or nearly linear nematic and smectic A-composition temperature dependence were observed. [ABSTRACT FROM AUTHOR]