• YAKHAK HOEJI
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• v.55 no.6
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• pp.441-445
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• 2011

A series of 8-(substituted)aryloxy- and 8-alkyloxy-caffenines were prepared from 8-bromocaffeine and (substituted) phenols as well as alkanols by Ullmann reaction and their inhibitory activities on topoisomerase II were evaluated. A compound, 8-(quinolin-2-yl)oxycaffeine showed the strongest inhibitory activity against topoisomerase II.

• Bulletin of the Korean Chemical Society
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• v.26 no.10
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• pp.1614-1616
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• 2005

• Bulletin of the Korean Chemical Society
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• v.35 no.11
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• pp.3219-3223
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• 2014

Ochnaflavone, a naturally occurring biflavonoid composed of two units of apigenin (5,7,4'-trihydroxyflavone) joined via a C-O-C linkage, was first synthesized and evaluated its inhibitory activity on $PGE_2$ production. Total synthesis was accomplished through modified Ullmann diaryl ether formation as a key step. Coupling reactions of 4'-halogenoflavones and 3'-hydroxy-5,7,4'-trimethoxyflavone were explored in diverse reaction conditions. The reaction of 4'-fluoro-5,7-dimethoxyflavone (2c) and 3'-hydroxy-5,7,4'-trimethoxyflavone (2d) in N,N-dimethylacetamide gave the coupled compound 3 in 58% yield. Synthetic ochnaflavone strongly inhibited PGE2 production ($IC_{50}=1.08{\mu}M$) from LPS-activated RAW 264.7 cells, which was due to reduced expression of COX-2. On the contrary, the inhibition mechanism of wogonin was somewhat different from that of ochnaflavone although wogonin, a natural occurring anti-inflammatory flavonoid, showed strong inhibitory activity of $PGE_2$ production ($IC_{50}=0.52{\mu}M$), and seems to be COX-2 enzyme inhibition. Our concise total synthesis of ochnaflavone enable us to provide sufficient quantities of material for advanced biological studies as well as to efficiently prepare derivatives for structure-activity relationship study.

• Journal of the Korean Graphic Arts Communication Society
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• v.16 no.3
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• pp.133-146
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• 1998

The conversion of 1-Amino-4-(3'-Acetaminoanilino) Anthraquinone-2-Sulfonic Acid prepared by the Ullmann condensation have been investigated as a function of the reaction conditions such as catalysts, initial concentration of reactants, reaction temperature, pH, condensation agents and neutralizing agents. The experimental results showed that the Cu(I)-type catalysts had higher activity than the Cu(II)-type catalysts in this study. The conversion increased with increasing initial concentration of reactants but decreased at above critical concentration owing to agglomeration of reactants. It was also observed that the maximum conversion obtained at 7$0^{\circ}C$ and pH=7~8.

• Korean Journal of Materials Research
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• v.15 no.7
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• pp.448-452
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• 2005

This study was based on organic electroluminescence display. Especially, TPD and $\alpha-NPD$ for the hole transport materials were synthesized by Ullmann reaction. This reaction was conducted between 3­methylphenylamine, 1-naphthylamine and 4,4'-diiodobiphenyl in toluene containing CuCl catalyst and KOH base. The structural property of reaction products were analyzed by FT-IR, $^1H-NMR$ spectroscopy, and thermal stability, reactivity and PL property were analyzed by melting point, yield and emission spectrum, respectively. The photoluminescence spectra of a pure TPD and $\alpha-NPD$ were observed at approximately 416nm and 438nm respectively. In this study, it was known that the melting point, yield, PL properties of TPD and $\alpha-NPD$ were changed by substituent group of amines.

• Applied Chemistry for Engineering
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• v.5 no.3
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• pp.413-418
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• 1994

The synthetic steps of sodium(2-(2, 6-dichlorophenyl)amino)phenylacetate were reduced and increased the yield in each steps. The synthetic process was composed to four steps and 2, 6-dichloroaniline and per catalyst in three lots in 80% yield. The steps of acylation and Friedel-Craft reaction were simplified successfully. The final product, diclofenac was obtained in 97% yield by hydrolyzing 1-(2,6-dichlorophenyl)-2-indolinone which was gained in third step with Claisen-solution.