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European chemical bulletinVol. 7., No. 9. (2018.)


Classical and advanced chemical sciences

  • Taha A. Ameen ,
    A.A. Fadda :

    Several novel arylbisazopyrazolo[1,5-a]pyrimidines were synthesized from diazotization of 4-aminoazobenzene and coupling with malononitrile and then refluxed with hydrazine hydrate to give 3,5-diamino-4-arylbisazo-1H-pyrazole.The later compound was diazotized and coupled with bifunctional reagents to produce novel heteroarylbisazo dyestuffs. Structural characterization of these novel dyes was carried out using IR, 1H NMR, and mass spectroscopy.

    Keywords: p-Aminoazobenzene, malononitrile, acetylacetone, pyrazolo[1,5-a]pyrimidine, hydroxyl amine

  • Vasiliy Georgievich Shtamburg ,
    Victor Vasilievich Shtamburg ,
    Andrey Alexandrovich Anishchenko ,
    Svetlana Vladimirovna Kravchenko ,
    Alexander Vladimirovich Mazepa ,
    Evgeniy Alexandrovich Klots :

    Decarbamoylation of N-alkoxy-N-(4-dimethylaminopyridin-1-ium-1-yl)urea chlorides in dimethylsulfoxide takes place with the formation of 1-alkoxyaminopyridinium chlorides. The nature of N-alkoxy substituents has a great influence on decarbamoylation efficiency. Decarbamoylation of N-n-butyloxy-N-(4-dimethylaminopyridin-1-ium-1-yl)urea chloride at 20 ºC occurs with the selective formation of 1-n-butyloxyamino-4-dimethylaminopyridinium chloride. N-Methoxy-N-(4-dimethylaminopyridin-1-ium-1-yl)urea chloride is stable in dimethylsulfoxide at 20 ºC, but it forms selectively 1-methoxyamino-4-dimethylaminopyridinium chloride at 82 ºC in 1 h. N-Ethoxy-N-(4-dimethylaminopyridin-1-ium-1-yl)urea chloride is also stable in dimethylsulfoxide at 20 ºC, but it converts into 1-ethoxyamino-4-dimethylaminopyridinium chloride at 100 ºC under heating for 3 h.

    Keywords: N-alkoxy-N-(pyridin-1-ium-1-yl)urea chlorides; decarbamoylation; 1-alkoxyamino-4-dimethylaminopyridinium chlorides; structure; O-N-N geminal systems; dimethylsulfoxide

Materials and environmental chemistry

  • Garima Ameta ,
    Pinki B. Punjabi :

    This study underscores the development of Ag-PEG-Ch nanocomposite film using the aqueous leaves extract of Cannabis sativa under the influence of ultrasound, as smart substrates for antimicrobial uses, via innovative in situ reactive and reduction pathways. Ag nanoparticles that are synthesized by using leaves extract and ultrasound as an energy source have emerged as nontoxic and ecofriendly. In this study, silver nitrate was used as a silver precursor and PEG and chitosan were used as the polymeric stabilizer and solid support, while cannabis sativa leaves extract acts as a green reducing agent. This polymer metal film was characterized by FT-IR, SEM, TEM, TGA, DSC and antimicrobial activities. XRD peaks clearly reveals that FCC Ag nanoparticles embedded in polymer matrix, very fine Ag nanoparticles (4-6 nm) can be synthesized through ultrasound has been proven by TEM images and TGA-DSC results show that this nanocomposite film is thermally stable. This nanocomposite film possesses synergistic biocidal activities also.

    Keywords: Biosynthesis, crosslinking, nanocomposite, ultrasound, biocidal activity

  • Franco Cataldo :

    Landfill leachate derived from the landfilling practice of the municipal wastes is a problem affecting all countries and continents. Even after the shutdown of a landfill site, the leachate production continues for decades. In this work a solution for the landfill leachate treatment has been proposed based on three fundamental steps: the pre-ozonolysis of the leachate, the passage of the ozonized leachate through a fixed bed of activated carbon and the final step consisting in a photo-ozonolysis stage involving the simultaneous action of ozone and UV light. A distinction between the chemical structure and chemical behaviour of young and mature leachate was evidenced by thermal analysis of the soluble organic matter (SOM) obtained from these substrates. Furthermore, a distinction between young and mature leachate was also evidenced in terms of their different reactivity toward ozone as illustrated by the COD abatement and by FTIR spectroscopy on pristine and ozonized SOM. A modular pilot plant for the treatment of different landfill leachates was presented and proposed.

    Keywords: landfill leachate; ozone; adsorption; activated carbon; photo-ozonolysis; pilot plant

Chemical and biological aspects of life

  • Iman M. A. El-Kholy ,
    M. H. Abul-Aziz ,
    Atef M. Diab ,
    Mona A. Rezk :

    Multiplex PCR for the detection of AmpC genes has proved useful as a rapid screening tool to distinguish cefoxitin resistant non-AmpC producers from cefoxitin resistant AmpC producers. In addition to AmpC gene detection, the data generated from the multiplex PCR method can distinguish which family of AmpC gene is present in the resistant organism thereby distinguishing possible inducible AmpC producers from non-inducible producers of AmpC. The present study was designed to evaluate these issues among cephalosporin-resistant isolates of Klebsiella spp. and to assess the performance characteristics of phenotypic tests, using different inhibitors, compared to the PCR, for their rapid and accurate detection. Fifty eight out of 100 isolates were AmpC producers by PCR. Fifty six out of 58 isolates that were positive by PCR test were resistant to FOX. Thirty out of 58 AmpC producers were ESBL positive by E- test and MDDST in detection of ESBL in the presence of AmpC. While 23 /58 were positive by DDST for detection of ESBL in presence of Amp. This study reveals high prevalence of pAmpC and ESBL enzymes among bacterial isolates from our hospital. ESBL production may mask the phenotypic detection of pAmpC enzymes. Modified 3 dimensional(M3D) is a simple and reliable method for detection of pAmpCs. MDDST serve as reliable confirmatory tests for detection of ESBLs in AmpC-positive isolates.

    Keywords: Multiplex PCR, cefoxitin resistant Klebsiella-AmpC β-lactamase.

Theoretical and computational chemistry

  • G. А. Korablev :
    Energy criteria in biosystems246-253en [418.92 kB - PDF]EPA-02286-00066-0060

    An analysis of the orientation of structural interactions was carried out on the basis of the first law of thermodynamics. In the systems in which the interaction proceeds along the potential gradient (positive work), the resultant potential energy is found based on the principle of adding reciprocals of corresponding energies of subsystems - there is a corpuscular mechanism. In the systems in which the interactions proceed against the potential gradient (negative performance) the algebraic addition of their masses, as well as the corresponding energies of subsystems is performed - there is a wave mechanism. Act of quantum action expressed via Plank’s constant is narrowed to the energy equilibrium-exchange redistribution between the corpuscular and wave processes, which is demonstrated via the angular vector of such motion. Energy characteristics of functional states of bio-systems are defined basically by P-parameter values of atom first valence electron. The principles of stationary biosystem formation are similar to the conditions of wave processes in the phase. Under the condition of the minimum of such interactions, the pathological (but not stationary) biostructures containing the molecular hydrogen can be formed.

    Keywords: Potential gradient; corpuscular-wave dualism; Spatial-energy parameter; biosystems; stationary and pathological states