• Journal of the Korean Applied Science and Technology
• /
• v.17 no.2
• /
• pp.113-119
• /
• 2000

Alkylation of phenol with tert-butanol in the liquid phase on mordenite was studied. The influence of many reaction parameters such as calcination temperature, reaction temperature, t-butanol/phenol molar ratio on catalytic properties was discussed. The main products were 2,4-di-t-butylphenol, o-t-butylphenol, p-t-butylphenol, the last of these was wanted product. In order to enhance the selectivity of p-t-butylphenol, optimum conditions were recommended at $500^{\circ}C$ calcination temperature, $140^{\circ}C$ reaction temperature, 1.0 molar ratio of reactants over mordenite. P-t-butylphenol was formed with 90% isomer selectivity at optimum conditions after 4hr reaction. On the basis of the behavior obtained in the cases mentioned, optimum conditions and catalytic properties for t-butylation of phenol were provided.

• Bulletin of the Korean Chemical Society
• /
• v.35 no.6
• /
• pp.1743-1748
• /
• 2014

A facile and effective method has been developed for the synthesis of a novel series of benzofuran derivatives via N-acylation, O-alkylation and intramolecular condensation reactions, starting from readily available substituted o-hydroxy aryl ketone, and chloroacetyl arylamides. This metal-free transition process is characterized by mild reaction conditions, atom economy, short reaction time and a high yield with a decreased amount of by-products.

• Journal of the Korean Chemical Society
• /
• v.25 no.3
• /
• pp.199-205
• /
• 1981

7-Alkyl-1-carboxyphenazine derivatives, bearing butyl or octyl group, were synthesize by the reaction of anthranilic acid with 3-nitroalkylbenzene, prepared from aniline and alcohols as starting materials through alkylation of 3-nitro-4-aminoalkylbenzene. And the products were also identified by elementary analysis, IR and NMR spectra. Surface tension of these derivatives in aqueous solution was determined. And also Antibiotic activity of these derivatives was tested, using Gram positive and negative bacillus and fungi. It showed that the antibiotic activity of these alkyl-substituted 1-carboxyphenazine derivatives was stronger than that of the 1-carboxyphenazine.

• Bulletin of the Korean Chemical Society
• /
• v.24 no.2
• /
• pp.225-228
• /
• 2003

• YAKHAK HOEJI
• /
• v.34 no.4
• /
• pp.262-266
• /
• 1990

Acetylshikonine, isolated from the root of Lithospermum erythrorhizon showed a strong cytotoxic activity ($ED_{50}=0.10\;ug/ml$) against L1210 cell and T/C = 182% in ICR mice bearing S-180 at a dose of 5 mg/kg. Administrations of 10 mg/kg and 15 mg/kg reduced the T/C values to 60 and 77% respectively. Higher doses reveal toxicity. Seven naphthazarin derivatives synthesized showed good cytotoxic activities against L1210 cell. Especially, naphthazarin and hydronaphthazarin have strong activities ($ED_{50}=0.05\;ug/ml$ for both). Naphthazarin showed a severe toxic effect on ICR mice bearing S-180; no significant toxic effect was observed at a dose of 1 mg/kg or 2 mg/kg, but a severe toxicity (T/C = 23%) by administration of 5 mg/kg. Alkylation of C-2 of naphthazarin is necessary for reducing the toxic effect on ICR mice bearing S-180.

• Proceedings of the Korean Society of Applied Pharmacology
• /
• 1992.05a
• /
• pp.16-16
• /
• 1992

1940년대에 처음으로 암의 화학요법이 시도된 이래 많은 항암제들이 도입되어 사용되고 있다. 현재 항암제를 사용하여 비교적 치료율이 높은 암은 leukemia나 lymphoma와 같은 혈액암에 국한되어 있다. 고형암에 대하여는 고환암과 같은 극히 일부가 항암제에 의해 비교적 잘 치료되나 대부분은 여전히 치료가 되지 않고 있는 상태에 있다. 고형암의 발생빈도는 전체 암의 90％를 차지하고 있는 상태로 사망율이 매우 높아, 현대의 40대 이상 사망원인의 1위를 나타내고 있어 그 치료제의 개발이 매우 시급히 요구되고 있다. 이에 따라 고형암의 치료를 목적으로 많은 화합물들이 검토되어 왔다. 이중 최근 매우 큰 가능성을 보여주고 있는 diarysulfonylurea 유도체가 발견되어 임상시험에 도입됨으로서 이 화합물들에 대한 관심이 고조되고 있다. 이와 관련하여 고형암의 치료제를 개발할 목적으로 diarysulfonylurea의 특성과 강력한 항암효과를 발현하는 alkylating agent의 특성을 갖을 것으로 예상되는 새로운 2-alkoxy-1-arylsufonylimidazoline 유도체를 설계하고, 이들 유도체의 합성법을 개발하였다. 이들 유도체들은 일차적으로 생체내에서 DNA 또는 효소등에 alkylation을 일으킨후 diarysulfonylurea로 변하여 작용함으로서 보다 큰 항암효과를 발현할 것으로 기대된다.

• Journal of Photoscience
• /
• v.1 no.2
• /
• pp.107-111
• /
• 1994

Photocatalytic ($\lambda$$_{ex}$ > 300 nm) reaction at room temperature by platinized titanium (IV) oxide particles produced 1-methyl-1, 2, 3, 4-tetrahydroisoquinolines (MIQ's) from phenethylamines in aqueous ethanol suspension under deaerated atmosphere. Among the phenethylamines, dopamine (2-(3, 4-dihydroxyphenyl) ethylamine) showed the highest reactivity to give MIQ almost selectively under the neutralized conditions. The other phenethylamines gave predominantly N-alkylated and N, N-dialkylated products in the methanol or ethanol solutions. The reaction mechanism includes a Schiff base intermediate to undergo either nucleophilic attack leading to MIQ or reduction to N-alkylated products.

• Proceedings of the KAIS Fall Conference
• /
• 2011.05a
• /
• pp.144-146
• /
• 2011

Al-MCM-48 molecular sieves (Si/Al = 25, 50, 75 and 100) were synthesized hydrothermally using cetyltrimethyl ammonium bromide as the structure directing template. The orderly arrangement of mesopores was evident from the low angle X-ray diffraction patterns and TEM images. The catalytic performance was evaluated in the vapour phase isopropylation of phenol with isopropyl acetate. Phenol conversion decreased with increase in the Si/Al ratio of the catalysts. The major reaction product was 4-isopropyl phenol (selectivity: 78%). Delocalization of phenolic oxygen electron pair over the aromatic ring promoted para-selective alkylation. Such delocalization could be aided by the hydrophilic surface of the molecular sieves. Though ester was used as the alkylating agent, phenyl isopropyl ether was not formed

• Journal of the Korean Chemical Society
• /
• v.33 no.3
• /
• pp.321-325
• /
• 1989

There has been a continuing interest in the sterols and sterodis of marine organisms. The most exciting results of recent studies have been the characterization of a host of novel sterols, many with unique alkylation patterns in the side chain, but some with modified ring structures. The isolation and characterization of three sterols from the Korean alga codium fragile are presented. The major sterol was (24S)-24-ethylcholesta-5,25-dien-3${\beta}$-ol (clerosterol) and two minors are codisterodl and cholesterol.

• Macromolecular Research
• /
• v.14 no.1
• /
• pp.107-113
• /
• 2006

Processible norbornene copolymers were realized by judiciously designing norbomene comonomers, which were themselves prepared by the Diels-Alder reaction of cyclopentadiene and benzoquinone followed by the isomerization and alkylation of alcohols. The norbornene copolymers containing these derivatized comonomers, prepared by [Pd($x_{2}CH-{3} $)$_{4}$][$SbF_{6}$]$_{2}$ catalyst, exhibited excellent solubility in many organic solvents as well as good thermal stability, as evidenced by their high glass transition ($T_{g}$) and decomposition ($\∼$350$^{circ}C$) temperatures. In addition, fairly strong adhesion to substrates such as glasses and silicon wafers was also achieved with these copolymers to overcome the limitations experienced by polynorbornene homopolymers and to make them attractive for many important industrial applications.