Polarographic Behaviour and Physico-Chemical Characteristics of Some 5-Arylazopyrimidines of Biological Significance

1992 ◽  
Vol 57 (10) ◽  
pp. 2042-2052
Author(s):  
Mohamed I. Ismail

The polarographic behaviour of a series of the title compounds has been investigated in aqueous alcoholic buffered media and in DMF-0.1M-LiClO4. A mechanism interpreting the electrode process was suggested and confirmed via the identification of CPE products, the use of models and the Hamett's σ-E1/2 relationship. The different physico-chemical characteristics of these compounds were also determined. A linear correlation was shown to exist between their redox potentials and spectroscopic data.

1993 ◽  
Vol 58 (9) ◽  
pp. 1978-1988
Author(s):  
Mohamed I. Ismail ◽  
Madlene L. Iskander

The polarographic behaviour of a series of arylazotheophyllines was studied in aqueous alcoholic buffer media and in DMF-0.1 M LiClO4 solution. The redox study gave evidence that the azo group is electroactive in aqueous as well as non-aqueous media. A mechanism interpreting the electrode process is proposed and confirmed through the identification of the controlled potential electrolysis products, the use of a model compound and the application of Hamett's σ-E relationship. The physico-chemical characteristics of these compounds, viz. the diffusion coefficient, dissociation constant, ionization potential and electron affinity, are also included.


2019 ◽  
Vol 70 (7) ◽  
pp. 2534-2537
Author(s):  
Gladiola Tantaru ◽  
Mihai Apostu ◽  
Antonia Poiata ◽  
Mihai Nichifor ◽  
Nela Bibire ◽  
...  

The paper presents the synthesis of a new complex combination of a Bis-Schiff base with Mn(II) ions with great potential for antimicrobial and anti-inflammatory activity. A new complex of the Salen-type ligand, 1-ethyl-salicylidene-bis-ethylene diamine was synthetized using Mn(II) ions. The chemical structure was confirmed through 1H-NMR and IR spectroscopy. The antimicrobial activities of the Bis-Schiff base and its complex were tested in comparison with Ampicillin, Chloramphenicol, Tetracycline, Ofloxacin and Nystatin. Those compounds were found to be active against Gram-positive or Gram-negative bacteria, and had an anti-inflammatory effect comparable to that of Indomethacin.


2020 ◽  
Vol 16 (5) ◽  
pp. 685-707 ◽  
Author(s):  
Amna Batool ◽  
Farid Menaa ◽  
Bushra Uzair ◽  
Barkat Ali Khan ◽  
Bouzid Menaa

: The pace at which nanotheranostic technology for human disease is evolving has accelerated exponentially over the past five years. Nanotechnology is committed to utilizing the intrinsic properties of materials and structures at submicroscopic-scale measures. Indeed, there is generally a profound influence of reducing physical dimensions of particulates and devices on their physico-chemical characteristics, biological properties, and performance. The exploration of nature’s components to work effectively as nanoscaffolds or nanodevices represents a tremendous and growing interest in medicine for various applications (e.g., biosensing, tunable control and targeted drug release, tissue engineering). Several nanotheranostic approaches (i.e., diagnostic plus therapeutic using nanoscale) conferring unique features are constantly progressing and overcoming all the limitations of conventional medicines including specificity, efficacy, solubility, sensitivity, biodegradability, biocompatibility, stability, interactions at subcellular levels. : This review introduces two major aspects of nanotechnology as an innovative and challenging theranostic strategy or solution: (i) the most intriguing (bare and functionalized) nanomaterials with their respective advantages and drawbacks; (ii) the current and promising multifunctional “smart” nanodevices.


1989 ◽  
Vol 54 (1) ◽  
pp. 117-135
Author(s):  
Oldřich Pytela ◽  
Vítězslav Zima

The method of conjugate deviations based on the regression analysis has been suggested for construction of a new nucleophilicity scale. This method has been applied to a set of 28 nucleophiles participating in 47 physical and chemical processes described in literature. The two-parameter nucleophilicity scale obtained represents-in the parameter denoted as ND-the general tendency to form a bond to an electrophile predominantly on the basis of the orbital interaction and-in the parameter denoted as PD-the ability to interact with a centre similar to the proton (basicity). The linear correlation equation involving the ND, PD parameters and the charge appears to be distinctly better than the most significant relations used. The correlation dependences have the physico-chemical meaning. From the position of individual nucleophiles in the space of the ND and PD parameters, some general conclusions have been derived about the factors governing the reactivity of nucleophiles.


Foods ◽  
2021 ◽  
Vol 10 (2) ◽  
pp. 225
Author(s):  
Asma Ghorab ◽  
María Shantal Rodríguez-Flores ◽  
Rifka Nakib ◽  
Olga Escuredo ◽  
Latifa Haderbache ◽  
...  

This study aimed to characterize the honeys of Babors Kabylia through sensory, melissopalynological and physico-chemical parameters. Thirty samples of honey produced in this region were collected over a period of two years and analyzed. All the samples presented physico-chemical parameters in conformity with legislation on honey quality, with few exceptions, linked mainly to beekeeping management. The pollen spectrum revealed a great diversity with 96 pollen types. The main pollen types were spontaneous species as Fabaceae (Hedysarum, Trifolium, Genisteae plants), Asteraceae plants, Ericaceae (Erica arborea L.) or Myrtus and Pistacia. The sensory properties of samples showed a high tendency to crystallization, the colors were from white to brown, but most of them had gold color. Smell and odor corresponded mainly to vegetal and fruity families and in taste perceptions besides sweetness highlighted sourness and saltiness notes. Seventeen samples were polyfloral, one was from honeydew and twelve were monofloral from heather, genista plants, sulla, blackberry or Asteraceae. Heather and the honeydew samples showed the darkest color, the highest electrical conductivity and phenol and flavonoid content. A statistical analysis based on the most representative pollen types, sensory properties and some physico-chemical components allowed the differentiation of honey samples in terms of botanical origin.


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