Halogeno-alkyl Glycosides. II. Dihalogeno-alkyl Derivatives

: A retrospective view of exaltation of refraction observed for many unsaturated and aromatic compounds demonstrates that this physical phenomenon is undeservedly considered only as a qualitative measure of conjugation. This mini-review discusses numerous papers by the author that have been published earlier in inaccessible periodicals and collections of scientific papers. Using a great number of illustrations, the author shows that this parameter can be successfully used for quantitative estimate of resonance effects in organic and polymer chemistry. The methods for derivation of strictly additive atomic and group refraction constants are described; these constants were subsequently used as a tool that allowed quantitative estimation of resonance effects in mono-, di-, tri- and polyalkylbenzenes, alkylnaphthalenes, some alkyl derivatives of unsaturated hydrocarbons. These effects cause strictly fixed increase in refraction of carbon atoms in different structural modifications (graphene, fullerene, diamond) and in polycyclic aromatic hydrocarbons. The relevant results regarding quantitative estimation of degree of steric inhibition of resonance in sterically hindered ortho-dialkylbenzenes, 1,2,3- trialkyl-, 1,2,3,4-tetraalkyl-, and 1,2,3,4,5-polyalkylbenzenes accumulated by the author are summarized.

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Synthesis and Biological Evaluation of Scutellarein Alkyl Derivatives as Preventing Neurodegenerative Agents with Improved Lipid Soluble Properties

Medicinal Chemistry ◽

10.2174/1573406414666181015143551 ◽

2019 ◽

Vol 15 (7) ◽

pp. 771-780

Author(s):

He-Min Li ◽

Ting Gu ◽

Wen-Yu Wu ◽

Shao-Peng Yu ◽

Tian-Yuan Fan ◽

...

Keyword(s):

Antioxidant Activity ◽

Neuronal Damage ◽

Thiobarbituric Acid ◽

Rat Hepatocytes ◽

Biological Evaluation ◽

Thiobarbituric Acid Reactive Substance ◽

Alkyl Derivatives ◽

Promising Therapeutic Approach ◽

Microsomal Membranes

Background: Exogenous antioxidants are considered as a promising therapeutic approach to treat neurodegenerative diseases since they could prevent and/or minimize the neuronal damage by oxidation. Objective: Three series of lipophilic compounds structurally based on scutellarein (2), which is one metabolite of scutellarin (1) in vivo, have been designed and synthesized. Methods: Their antioxidant activity was evaluated by detecting the 2-thiobarbituric acid reactive substance (TBARS) produced in the ferrous salt/ascorbate-induced autoxidation of lipids, which were present in microsomal membranes of rat hepatocytes. The lipophilicity of these compounds indicated as partition coefficient between n-octanol and buffer was investigated by ultraviolet (UV) spectrophotometer. Results: This study indicated that compound 5e which had a benzyl group substituted at the C4'- OH position showed a potent antioxidant activity and good lipophilicity. Conclusion: 5e could be an effective candidate for preventing or reducing the oxidative status associated with the neurodegenerative processes.

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7-O-Alkyl derivatives of daunomycinone

Collection of Czechoslovak Chemical Communications ◽

10.1135/cccc19840313 ◽

1984 ◽

Vol 49 (1) ◽

pp. 313-319 ◽

Cited By ~ 4

Author(s):

Věra Přikrylová ◽

Petr Sedmera ◽

Josef V. Jizba ◽

Jindřich Vokoun ◽

Helena Lipavská ◽

...

Keyword(s):

H Nmr ◽

Toluenesulfonic Acid ◽

Alkyl Derivatives ◽

Derivatives Of

Reaction of daunomycinone (I) with alcohols and p-toluenesulfonic acid produces a mixture (~3 : 1) of its (7S)- and (7R)-O-alkyl derivatives II-IX. According to the 1H NMR evidence, the alicyclic ring exists in the 9H8 conformation in (7R)-O-alkyl derivatives, on the contrary to (7S)-epimers and 7-epi-daunomycinone that adopt the 8H9 conformation.

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Polarized fluorescense of alkyl derivatives of fluorescein, MitoFluo and C8-Fl, in solutions with liposomes

2020 International Conference Laser Optics (ICLO) ◽

10.1109/iclo48556.2020.9285751 ◽

2020 ◽

Author(s):

D.M. Beltukova ◽

V.P. Belik ◽

Y.N. Antonenko ◽

A.A. Bogdanov ◽

G.A. Korshunova ◽

...

Keyword(s):

Alkyl Derivatives ◽

Derivatives Of

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Assessment of Indoor Benzene and Its Alkyl Derivatives Concentrations in Offices Belonging to University of Technology (Poland)

Atmosphere ◽

10.3390/atmos12010051 ◽

2020 ◽

Vol 12 (1) ◽

pp. 51

Author(s):

Barbara Kozielska ◽

Dorota Kaleta

Keyword(s):

Dominant Role ◽

Average Concentration ◽

Air Contamination ◽

Flame Ionization ◽

Indoor Sources ◽

Alkyl Derivatives ◽

University Of Technology ◽

Low Concentrations ◽

Office Rooms ◽

Indoor And Outdoor

Indoor air contamination in office rooms is regarded as one of the most important issues in the protection of workers’ health, because contaminants, even those occurring at low concentrations, can cause health problems for the office staff in view of the long exposure time. This paper presents the results of measurements of benzene and its alkyl derivatives (toluene, ethylbenzene, xylenes, styrene, and 1,3,5-trimethylbenzene)—known indicators of human exposure to volatile organic compounds (VOCs) in the air in newly renovated offices at University of Technology (Upper Silesia, Poland). Monthly samples of indoor and outdoor air were collected during the years 2018–2019 by passive methods and analyzed by thermal desorption-gas chromatography with flame ionization detector (TD-GC/FID). In the first month of measurements average concentrations of the sum of five VOCs under consideration was 127.7 µg/m3, then in subsequent months between 15.1 µg/m3 to 87.3 µg/m3. The average concentration of carcinogenic benzene was below 1.5 μg/m3. Toluene had the highest concentration among studied VOCs, accounting for as high as 60% and 84% of the total indoor and outdoor VOCs, respectively. High indoor-to-outdoor (I/O) ratios for ethylbenzene (7.1), m,p-xylene (9.8), and styrene (12.5) indicate the dominant role of indoor sources.

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