Chemistry Journal of Moldova

 

Abstract (PDF)
Graphical Abstract: Amorphous alloy are materials have been around for some time and their applications can be found in many types of industrial products. Currently, the production of the amorphous alloy Co69Nb25B6 was obtained by high-energy ball milling which allows the formation of phases through solid state reaction through consolidation process. In addition, the effects of a 21:1 powder to ball mass ratio were used and the milling time during high energy milling was crucial for the formation of the amorphous and ferromagnetic phases. The characterization of the Co69Nb25B6 alloy was investigated by X-ray diffraction, scanning electron microscopy and by a vibrating sample magnetometer.


 

 

Abstract (PDF)
Supplementary Material (PDF) 

Graphical Abstract: A green and efficient method for the multicomponent synthesis of 3,4-dihydropyrimidin-2(1H)-ones and -thiones using acetic acid supported on activated charcoal as a mild acid catalyst in ethanol under both conventional as well as microwave irradiation conditions has been developed. The catalyst system found more efficient under microwave irradiation conditions than conventional conditions with shorter reaction times and excellent yields.


 

Abstract (PDF) 

Graphical Abstract: This paper presents the the main scientific and innovative results are presented, which were obtained by the talented chemist and renowned ecologist Valeriu Ropot throughout his scientific career. The results of scientific investigations are bestowed and analysed concerning the quality of the waters of the Dniester and the Prut Rivers, Dubasari reservoirs on the Dniester River, as well as the main bodies of water in the Republic of Moldova. The paper also includes the practical recommendations for reducing the negative impact on the environment, of the discharge of hundreds of thousands of tons of brine into the Dniester River as a result of the accident at the mineral fertilizer plant in the city of Stebnik, Ukraine. Moreover, the paper presents the results of studies aimed at developing methods for determining organic and inorganic pollutants in natural waters.


 

https:/doi.org/10.19261/cjm.2022.946   

 

Abstract (PDF)
Graphical Abstract: The composition of the lipophilic and hydrophilic extracts from the Feteasca Neagra ground seeds, grown in three different vineyards, was studied. The physicochemical indicators of the seeds, the oil quality indicators and the total content of polyphenols and flavonoids in the extracts were determined.  Some phenolic and flavanol constituents were identified and quantified using reversed-phase HPLC by gradient-elution. The Trolox equivalent antioxidant capacity assay proved the increased antioxidant activity of the hydrophilic extracts, with the highest DPPH• scavenging effect of almost 91.70 and 93.81%, an equivalent of 281.66 and 288.27 µM/L Trolox. It was concluded that the seeds recovered from Feteasca Neagra by-products are a rich source of functional compounds, with significant antioxidant properties. 


 

https://doi.org/10.19261/cjm.2022.892   

Abstract (PDF)
Supplementary Material (PDF)  

Graphical Abstract: Herein, an efficient one-pot synthesis is described, of substituted benzimidazole derivatives (3a-j) from a condensation of various o-phenylenediamine (1a-j) aromatic aldehyde (2a-j) using ZnFe₂O₄ as a nano-catalyst under ultrasonic irradiation conditions. All forms of aldehydes with an electron releasing or electron –withdrawing substituent have a significant yield. The catalyst can easily be recovered after completion of the reaction and reused without affecting its activity. Prepared benzimidazole derivatives showed moderate to good anti-tuberculosis results.


 

https://doi.org/10.19261/cjm.2022.958   

Abstract (PDF) 

Graphical Abstract: This review relates to chemistry of the well-known biologically active natural labdane diterpenoid (-)-sclareol easily available from Clary sage (Salvia sclarea L.). It is mainly used in industry, especially for synthesis of fragrance compounds and natural analogs. The paper covers achievements on the synthesis, structure determination and biological activity of molecular hybrid compounds bearing hydrazide and thiosemicarbazone fragments or diazine, 1,2,4-triazole, carbazole, 1,3-thiazole, 1,3,4-oxadiazole, 1,3,4-thiadiazole units prepared based on it. 


 

 

 

Abstract (PDF)
Graphical Abstract: This paper presents a study of the hydrochemical composition and physicochemical properties of natural water samples from various sources in the Voronezh and Moscow regions. Two model systems are proposed for assessing the state of the aquatic environment: UV spectroscopy with spectrum decomposition by the Gauss method and spontaneous aggregation of lecithin in a polar medium. Based on the performed investigation, it was determined that the size of lecithin aggregates decreases, and the value of their zeta potential increases with an increase in the content of hydrophobic compounds in natural water.


 

Abstract (PDF)
Graphical Abstract: The aim of the work was to study the isomerization of limonene on zeolite-containing biporous acid catalysts based on kaolin (from Ukraine). Results of this study show that at 160°C, the maximum isomer yield was 60–65% with an 80–90% conversion. The studied samples do not have a significant accumulation of carbonaceous deposits because limonene has high solubility, which helps to remove intermediate products of transformation from the surface of the samples. 


 

 

Abstract (PDF)
Graphical Abstract: Two coordinating compounds of zinc(II) (1) [Zn₂(DAnH₂)₂(1,3-bdc)₂(DMSO)₄] and nickel(II) (2) [Ni(DAnH₂)(1,4-bdc)(DMF)₂]_n were obtained based on dianilineglyoxime (DAnH₂), 1,3-benzenedicarboxylic acid (1,3-bdcH₂) and 1,4-benzenedicarboxylic acid (1,4-bdcH₂), where DMSO is dimethylsulfoxide and DMF is dimethylformamide. The molecular and crystalline structure of reported compounds were established by infrared spectroscopy and single crystal X-ray diffraction, and for 1, additionally, the ¹H and ¹³C NMR spectroscopy was used. According to data, the Zn(II) molecular complex is a binuclear and the Ni(II) is a 1D polymer compound. 


 

 

Abstract (PDF)
Graphical Abstract: The work was aimed at preparing the CA+A300 composite consisting of caffeic acid (CA) and fumed silica (A300) and at comparing the properties of CA in the solution and in the composite. The results showed that the solution and the composite are effective antioxidant/antimicrobial agents and that inclusion of CA in the CA+A300 composite provides its gradual release into solutions and reaction mixtures, thus ensuring a prolonged action of the compound.