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Synteza pochodnych dibenzo[b,f]f]oksepiny podstawionych w pierścieniu aromatycznym

Tobiasz Piotr, Krawczyk Hanna

Wiadomości Chemiczne

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2021

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[Z] 75, 11-12

1238--1257

EN

Stilbene derivatives are characterized by many beneficial biomedical properties. They show, inter alia, chemopreventive [28], anti-inflammatory and antioxidant properties [29]. One of the most popular stilbene derivatives are combretastatins, which can inhibit the polymerization process of microtubules [30]. Another stilbene derivative is, for instance, resveratrol, which is characterized by wide anti-cancer properties [31]. Dibenzo[b,f]oxepines also show advantageous and interesting biomedical properties. These compounds are stilbene analogs in which the two aromatic rings bond with each other with a vinyl bridge and an oxygen atom. Many dibenzo[b,f]oxepines have strong antipsychotic, anti-inflammatory, anti-depressant, insecticidal, anti-epileptic and anticancer properties [5]. Stilbenes and their precursors – oxepines, can be derived from azo compounds that are potential molecular photoswitches. These photoswitches are used in the socalled photopharmacology. The scope of photopharmacology is designing, synthesis, studying and using drugs, which activity can be controlled by light. The purpose of photopharmacology is also to solve the problem of off-target activity and severe side effects by establishing an external modality for controlling the action of the drug. The use of such drugs in treatment could prevent systemic and environmental side effects through the selective activation of them at the molecular target [1]. These molecular photoswitches based on oxepine ring could be extremely useful in photopharmacological therapy. The combination of azo group changing its configuration with the dibenzo[b,f]oxepine group should lead to the creation of interesting compounds. This is a promising combination of the medical properties of this bioactive compound with the function of the molecular photoswitch. A method of the synthesis of a series of azo dibenzo[b,f]oxepine derivatives was developed and implemented. Synthesized compounds can be used in the future as potential molecular photoswitches. For this purpose, a 4-step synthesis was conducted, starting from the simplest substrates – a benzaldehyde derivative and 2,4-dinitrotoluene (schem. 1).

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Electrical and photoresponse characteristics of 8-(1H-indol-3-ylazo)-naphthalene-2-sulfonic acid/n-Si photodiode

Zedan Islam T., El-Menyawy E. M., Nawar H. H.

Opto-Electronics Review

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2019

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Vol. 27, No. 4

348--354

EN

In this paper, of primary interest is to synthesis 8-(1H-indol-3-ylazo)-naphthalene-2-sulfonic acid (INSA) and to evaluate the main parameters of Au/INSA/n-Si/Al diode in dark and under illumination. Different techniques are used for interpreting the proposed INSA chemical structure. The dark current-voltage measurements were achieved in the temperature range of 293−413K. It is noticed that INSA films modify the interfacial barrier height of classical Au/n-Si junction. At low applied voltages, the I–V relation shows exponential behavior. The values ideality factor, n, and the barrier height, φ, are improved by heating. The abnormal trend of n and φ is discussed, and a homogenous barrier height of 1.45 eV is evaluated. The series resistance is also calculated using Norde's function and it changes inversely with temperature. The space charge limited current ruled with exponential trap distribution dominates at relatively high potentials, trap concentration and carriers mobility are extracted. The reverse current of the diode has illumination intensity dependence with a good photosensitivity indicating that the device is promising for photodiode applications.

3

Fizyczno-chemiczne metody usuwania związków biogennych z roztworów wodnych

Kaleta J.

Zeszyty Naukowe Politechniki Rzeszowskiej. Budownictwo i Inżynieria Środowiska

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2003

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z. 35 [204]

97-105

PL

W pracy przedstawiono kilka metod usuwania związków azotu i fosforu z roztworów wodnych. Wykazano, że skuteczną metodą usuwania jonów amonowych jest wymiana jonowa na klinoptylolicie. Natomiast wymiana jonowa na anionicie azotanoselektywnym okazała się efektywna w usuwaniu jonów azotanowych. Zastosowanie procesu koagulacji jest skuteczną metodą usuwania związków fosforu. Dobrymi reagentami okazały się związki żelaza i wapno hydratyzowane.

EN

The paper presents a few methods of nitric and phosphate compounds from water solution. It turned out that ion exchange on the clinoptilolites has been effective regarding removal of ammonium ions, however ion exchange on the nitrate selective Purolite A 520 E has been effective regarding removal of nitrate ions. Application of coagulation process was very desirable method removal of phosphate compounds. The good reagents showed iron chloride and hydrated lime.

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Characterization of Small Azocrown Ether Stereoisomers

Luboch E., Wagner-Wysiecka E., Kravtsov V., Kessler V.

Polish Journal of Chemistry

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2003

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Vol. 77 / nr 2

189-196

EN

The stable E- and Z-isomers of 10-membered azocrown ether have been isolated and studied by X-ray, 1H NMR and UV-Vis methods. Their structures in a solid state indicate the stretched conformation for trans-isomer and unstressed for cis-isomer. The concerted effect of azo-group _-conjugation with benzene residue and steric strain of molecular conformation results in the observed stability of isomers.

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Liquid Crystalline Properties of 4-Methyl-, 4-Ethyl- and 4-Propyl-4'-alkyloxyazobenzenes

Zienkiewicz J., Galewski Z.

Polish Journal of Chemistry

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2002

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Vol. 76 / nr 2-3

359-366

EN

Liquid crystalline properties of 4-methyl-4_-alkoxyazobenzenes (azo-1-n), 4-ethyl-4_- alkoxyazobenzenes (azo-2-n) and 4-propyl-4_-alkoxyazobenzenes (azo-3-n) are described. For these three homologous series, temperatures and enthalpies of phase transitions and the types of mesophases are presented. The influence of the alkoxy chain length on the sequence of mesophases, temperatures of the phase transitions and the entropy effects are discussed.

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Liquid Crystalline Properties of Azobenzenes : II. 4-Pentyloxy-, 4-Hexyloxy- and 4-Heptyloxy-4'-alkyloxyazobenzenes

Galewski Z.

Polish Journal of Chemistry

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1999

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Vol. 73, nr 9

1503-1511

EN

Three new groups of unsymmetrically alkyloxyazobenzenes are presented for the alyloxy chain length up to octadecyloxy. In each investigated compound the liquid crystalline mesophase, mainly nematic, was found.