• Environmental Analysis Health and Toxicology
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• v.12 no.3_4
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• pp.75-84
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• 1997

Chromatographic retention behavior and separation of various phenol derivatives on a Partisil 10 ODS 3 column-with mobile phase containing $\alpha$-cyclodextrin-were systematically studied. The decrease in k' values caused by the addition of cyclodextrins in the mobile phase was based on the formation of an inclusion complex, resulting in weakening of the hydrophobic interaction between solutes and the stationary phase. The content of the organic solvent in the mobile phase also influenced k' values of the solutes, and k' values increased with a decrease of the content of organic solvent in the mobile phase. A simple equation has been derived that reveals the hyperbolic dependence of the capacity factor on the total concentration of cyclodextrin. A plot of the reciprocal of the capacity factor against (CD)$_T$ gives a straight line and the dissociation constant, K$_D$, of the inclusion complex can be calculated from the slope. The capacity factor decreased with increasing temperature. The enthalpy was calculated from the slope of van't Hoff plots. Under optimum conditions, some mixtures of phenol derivatives were able to separated successfully.

• Bulletin of the Korean Chemical Society
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• v.25 no.12
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• pp.1907-1910
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• 2004

Generation of hydroxyl radical, one of their major active species in ozonation of water was directly observed with spin-trapping/electron spin resonance (ESR) technique using 5,5-dimethyl-pyrrolidine-1-oxyl (DMPO) as a spin-trapping reagent. Hydroxyl radical was trapped with DMPO as a stable radical, DMPO-OH. 80 mM of ozone produced $1.08{\times}10^{-6}$M of DMPO-OH, indicating that 1.4% of ${\cdot}$OH is trapped with DMPO if ${\cdot}$OH is produced stoichiometrically from ozone. Humic acid suppressed DMPO-OH generation in a dose-dependent manner. Generation rate of DMPO-OH was determined with ESR/stopped-flow measurement. Phenol derivatives increased the amount and generation rate of DMPO-OH, indicating that phenol derivatives enhance·OH generation during ozonation of water.

• Journal of Radiopharmaceuticals and Molecular Probes
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• v.4 no.1
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• pp.16-21
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• 2018

Organoboron compounds and their derivatives are synthetically versatile building blocks because they are readily available, stable, and highly useful for potential organic transformations. Arylboronic esters are of particular interest due to their well-established synthetic methods: transition metal catalyzed borylations of aryl halides. However, the use of aryl halides as an electrophile has one serious disadvantage: formation of toxic halogenated byproducts. A promising alternative substrate to aryl halides would be phenol derivatives such as aryl ethers, esters, carbamates and sulfonates. The phenol derivatives involve several advantages: their abundance, relatively low toxicity and versatile synthetic application. However, utilization of the aryl methyl ether, which is one of the simplest phenol derivatives, remains as a challenge, as C-OMe bond activation requires high activation energy and methoxides are not good leaving groups. Nevertheless, there have been a significant recent progress on ipso-borylation of aryl methyl ether including Martin's nickel catalysis. Here, we review the current advance on the borylation of carbon-oxygen bonds of unactivated C-OMe bond in aromatic compounds.

• Korean Journal of Weed Science
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• v.13 no.2
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• pp.89-95
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• 1993

The Inhibiting activity of newly synthesized phenol (E-series) and triazine (T-series) derivatives was evaluated by using thylakoid membranes extracted from cyanobacteria (Anacystis nidulans $R_2$). There were no significant differences between phenol derivatives and dinoseb to the thylakoid membrane extracted from wild type in the Hill reaction. However, a phenol derivative, E-24 which has no -Cl at phenyl ring, did not show any activity. The longer the length of R substituents was in phenol derivatives, the lower inhibiting activity was in the Hill reaction. Triazine derivatives, T-27, T-28, T-40, T-41, T-47 and T-48 were also compared with diuron and atrazine. Among triazine compounds, T-27 and T-28 showed 10 and 30 times activity as high as atrazine to wild type, respectively. Other triazine derivatives, T-40, T-41, T-47 and T-48 showed low inhibiting activity to wild and mutant type. A structural difference of T-27 and T-28 from T-40, T-41, T-47 and T-48 was the presented of -C-NH-. Both T-27 and T-28 were very closely associated with serine, an amino acid located at the 264th position of D1 protein because of the resistant ratio(R/S) to mutant G-264 were higher than that of atrazine.

• YAKHAK HOEJI
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• v.15 no.3_4
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• pp.87-92
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• 1971

Fourteen novel N,N'-disubstitued thiourea derivatives were synthesized by Hugershof reaction. Antitubercular activities of ten compounds against Mycobacterium tuberculosis H$_{37}$ Rv were tested and was found tat 1-cyclohexyl-3-(4-benzenesulfonepiperidide)-2-thiourea was considerably active at 1mg/ml and 1-$\alpha$-naphthyl-3-(4-benzenesulfonepiperidide)-2-thiourea was slightly active at 1mg/ml. Antibacterial activity of the newly synthesized compounds against E. coli, Sta. aureus and Streptococcus hemolyticus were also tested. 1-cyclohexyl-3-(4-benzenesulfonepiperidide)-2-thiourea was makedly active against E. coli, Sta, aureus and Streptococcus hemolyticus; Phenol coefficients against E. coli, Sta, aureus and Streptococcus hemolyticus were 30,17.5 and 21.3, respectively. 1,1'-p-phenylene-3,3'bis[N-(2-thiazolyl)-sulfamylphenyl]-2,2'-dithiourea and 1-$\alpha$-naphthyl-3-(4-benzenesulfonepiperidide)-2-thiourea were considerably active against E. coli: phenol coefficients, 18.8 and 37.5 respectively. 1-(4-ethoxyphenyl)3-(4-sulfamylphenyl)-2-thiourea was active against Streptococcus hemolyticus: phenol coefficients, 22.5. 1-$\alpha$-naphthyl-3-(4-sulfamylphenyl)-2-thiourea, 1-$\betha$-naphthyl-3-[4-N-(2-thiazolyl)-sulfamylphenyl]-2-thiourea and 1-$\alpha$-naphthyl-3-(4-benzenesulfonepiperidide)-2-thiourea were active against Sta. aureus: phenol coefficients, 17.5, 20.0 and 18.8 respectively.

• Applied Chemistry for Engineering
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• v.10 no.3
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• pp.349-353
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• 1999

A study was carried out to see the effects of phenol on the biological degradation of a wastewater containing 2,4-dichlorophenol and 2,4-dinitrophenol and the biodegradation kinetic coefficients of Eckenfelder's modified model for the activated sludge process. The system containing base mix (BM) which was formulated with essential energy sources and nutrients was run down and washed out when 2,4-dichlorophenol and 2,4-dinitrophenol was introduced into the base mix unit without acclimation to phenol. Whereas for the system acclimated to phenol, the treatment efficiency was 91.9% in terms of $BOD_5$ and treatability for each chemical of phenol, 2,4-dichlorophenol, and 2,4-dinitrophenol was 99.8%, 43.3% and 62.5% based on concentration, respectively. Additional BM was added into the combined unit containing phenol, 2,4-dichlorophenol, 2,4-dinitrophenol so that the better treatment efficiency was achieved for each compound. The biokinetic coefficient of Eckenfelder's modified model without phenol acclimation was not estimated because the system did not reach the steady state. Thc coefficient for the phenol acclimation was 12.44 /day, however it was changed as 46.91 /day in addition of both of phenol acclimation and 47 mg/l of BM. The results presented above could be useful for the process design and further study in the field of biodegradation of benzene derivatives.

• Bulletin of the Korean Chemical Society
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• v.17 no.7
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• pp.573-574
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• 1996

• Korean Journal of Fisheries and Aquatic Sciences
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• v.12 no.2
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• pp.95-102
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• 1979

Brevibacterium flavum treated with phenol derivatives, guaiacol and o-vanillin has been revealed the marked increased ability in glutamic acid fermentation as 14.2 g/l in o-vanillin treated, 12.5 g/l in guaiacol treated while the 7.0 g/1 in nontreated cell. The increased ability of phenol derivatives treated cells in glutamic acid fermentation was ascribed to the formation of charge-transfer complex between phenols and oxygen. The charge-transfer complex effectively supply the oxygen to the fermention system in spite of high potential gradient in oxygen transfer formed by high cell concentration as insulator on film of air-liquid interface.

• Korean Journal of Pharmacognosy
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• v.8 no.1
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• pp.23-29
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• 1977

The $^{13}C-chemical\;shifts$ of the phenolic coumarine derivatives, aesculetin, daphnetin and herniarin were studied on the basis of my previous report. All spectral data found in this report could be utilized to the structure elucidation of the unknown phenolic coumarine derivatives and other phenolic compounds. In addition, it is suggested that a long range coupling may occur in the following structure as represented by arrow.

• Korean Chemical Engineering Research
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• v.43 no.6
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• pp.662-667
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• 2005

2,3-Dihydrobenzofuran derivatives, important intermediates of medicines and agricultural chemicals, were prepared from aryl methallyl ethers over MCM-41 mesoporous material catalysts. Two mesoporous materials with Si/Al mole ratios of 40 and 50 were prepared to investigate the effect of acid site concentration on their catalytic activities. Aryl methallyl ethers with various substituents on their benzene rings were used to investigate the effect of electron density on benzene ring on the conversion of the ethers and the yield of 2,3-dihydorbenzofuran derivatives. The catalyst with a high acid site concentration showed high conversions, but it is difficult to correlate the yield of the derivatives with the acid site concentration. The increase in the electron density of the benzene ring by introducing electron-donating groups accelerated Claisen rearrangement reaction, resulting in the enhanced yield of the derivatives. On the other hand, the decrease in the electron density by introducing electron-attracting groups accelerated the cracking reaction of aryl methallyl ether by acid catalysts, producing phenol derivatives rather than 2,3-dihydrobenzofuran derivatives.