• Bulletin of the Korean Chemical Society
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• v.14 no.1
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• pp.79-81
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• 1993

Synthetic routes are described for the introduction of hydroxyalkyl groups to the upper rim of calix[4]arene. Treatment of p-bromocalix[4]arene methyl ether 3 with n-BuLi followed by para-formaldehyde produced p-hydroxymethylcalix[4]arene methyl ether 4 in 60% yield. p-Acetylcalix[4]arene methyl ether 7, obtained by Friedel-Crafts acetylation of calix[4]arene methyl ether 6, was reduced with NaBH4 to produce p-(1-hydroxy ethyl)calix[4]arene methyl ether 8 in 67% yield.

• Natural Product Sciences
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• v.4 no.4
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• pp.245-252
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• 1998

The unique sulphated phenolics, gallic acid 3-methyl ether 5-potassium sulphate, isoferulic acid 3-potassium sulphate, and ellagic acid 4,4'-dimethyl ether 3-potassium sulphate have been isolated from the flowers of Tamarix amplexicaulis Ehrenb. (Tamaricaceae). The hitherto unknown natural phenolic acid, gallic acid 3-methyl ether, together with the known phenolic, gallic acid, gallic acid 4-methyl ether, isoferulic acid, ferulic acid, ellagic acid, and ellagic acid 4,4'-dimethyl ether have been also separated and characterized. The structures were established by conventional methods, including electrophoretic analysis and confirmed by ESI-MS, $^1H-\;and\;^{13}C-NMR$.

• Journal of the Korean Applied Science and Technology
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• v.26 no.3
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• pp.306-316
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• 2009

In this study, block copolymer of polystyrene and polyethylene glycol methyl ether methacrylate(PEGMA) by ATRP(atom transfer radical polymerization) method was synthesized. 4 arm-molecule which contained halogen atom was synthesized for an initiator. With 4 arm-molecule monodispered polystyrene were synthesized by ATRP method. The molecular change of synthesized monodispersed polystyrene with respect to time was investigated and living polymer characteristic was confirmed. Block copolymer of polystyrene and polyethylene glycol methyl ether methacrylate(PEGMA) was synthesized by ATRP with macroinitiator which was synthesized from the monodispersed polystyrene(Mn=12000). The molecular weight of obtained PS-b-PEGMA was 22,000.

• Membrane Journal
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• v.25 no.6
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• pp.515-523
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• 2015

While commercial polystyrene-based ion exchange membranes have simple manufacturing processes, they also possess poor durability due to their brittleness. Poly(ethylene glycol)methyl ether methacrylate with hydrophilic side chains of poly(ethylene glycol) was used as a co-monomer to make the membranes have improved flexibility. Hydrophilicity/hydrophobicity of the anion exchange membranes were able to be adjusted by varying the chain lengths of the poly(ethylene glycol). For the preparation of the anion exchange membranes, a porous PE substrate was immersed into monomer solutions and thermally polymerized. The prepared membranes were subsequently reacted with trimethylamine to produce anion exchange functional groups, Quaternary ammonium salts. The prepared pore-filled anion exchange membranes were evaluated in terms of ion exchange capacity, electric resistance, elongation at break and water uptake.

• Archives of Pharmacal Research
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• v.28 no.11
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• pp.1233-1235
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• 2005

Two new biflavonoids, 3'-hydroxyamentoflavone-7-O-methyl ether (1) and 3'-hydroxyamentoflavone (2), were isolated from the fruits of Aristolochia contorta Bge. Their structures were elucidated by HR-ESI-MS, 1D-, and 2D-NMR spectroscopy.

• Archives of Pharmacal Research
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• v.21 no.3
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• pp.357-360
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• 1998

Two new 4-hydroxybenzyl alcohol derivatives (1 and 2) were isolated from the methanol extract obtained from fresh tubers of Gastrodia elata together with 4-hydroxybenzyl methyl ether, 4-hydroxybenzyl alcoho, bis(4-hydroxyphenyl)methane, 4-hydroxybenzaldehyde, $\beta$-sitosterol and plamitic acid. 1 and 2 were identified as 3-O-($4^1$-hydroxybenzyl)-$\beta$-sitosterol and 4-[$4^1$-($4^{11}$-hydroxybenzyloxy)benzyloxy]benzyl methyl ether, respectively, according to the spectroscopic data.

• The Korean Journal of Food And Nutrition
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• v.14 no.1
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• pp.20-27
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• 2001

The consumption of radish ( Rhaphanus sativus L.) sprout, which is Cruciferae family, is increasing because of its pungent flavor and taste. Its volatile components were analyzed by SDE (simultaneous steam distillation & extraction) method and P&T(purge & cryogenic trapping) method. As a solvent, diethyl ether and diethyl ether : pentane mixture(2:1, v/v) were used in SDE method, and diethyl ether in P&T method. Analyzing by GC and GC-MS, the major component was sulfur compounds (19 species, peak area 76.6%) with diethyl ether, sulfur compounds(15. 44.0%) and hydrocarbons(23, 23.8%) with diethyl ether-pentane mixture in SDE method. Also, hydrocarbons(25, 84.1% ) was major component in P& T method. The major volatile component of fresh radish sprout were n-heptane, methyl pentane and that of boiled radish sprout were 4-methylthio-3-butenyl isothiocyanate, methyl mercaptane, 2,3-dimethyl disulfide. Low molecular volatile components were detected more by P& T method, but types and relative quantities of volatile components were measured less comparing to SDE method.

• Proceedings of the Korean Fiber Society Conference
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• 2000.04a
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• pp.13-16
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• 2000

• Fibers and Polymers
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• v.2 no.1
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• pp.131-134
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• 2001

Living cationic polymerization behaviors of isobutyl vinyl ehters (IBVE), initiated by iodomethyl methyl ether (IMME)/zinc iodide ($Znl_2$) have been investigated. The polymerization was carried out at 0, -15, and $-30^{\circ}C$ in toluene. It was found that the rate of polymerization increased as the IMME concentration increased and decreased as temperature decreased. 100% conversion was always achieved without exception. Furthermore, the number-average molecular weight ($M_{n}$) of polymers increased in direct proportion to monomer conversion. The molecular weights of polymers were in good agreement with the theoretical values, calculated on the basis that one polymer chain was formed by one IMME molecule and the values of polydispersity index are always less than 1.2, revealing the living nature. The living nature was also confirmed by synthesis of poly(IBVE-b-TBVE) by subsequent monomer addition of t-butyl vinyl ether (TBVE).

• Journal of the Korean Wood Science and Technology
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• v.29 no.4
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• pp.53-59
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• 2001

The needles of torreya(Torreya nucifera S. et Z) were collected, extracted with acetone-$H_2O$(7:3, v/v), fractionated with hexane, chloroform and ethylacetate, and freeze dried to give some dark brown powder. The ethylacetate soluble mixture was chromatographed on a Sephadex LH-20 column using a series of aqueous methanol and ethanol-hexane mixture as eluents. Most of the needle extractives were flavan and its methyl ether compounds such as (+)-catechin, (-)-epicatechin, (+)-gallocatechin, (-)-epigallocatechin, 3'-O-methyl-(+)-catechin and 3'-O-methyl-(-)-epicatechin including protocatechuic acid, one of benzoic acids. $^1H$- and $^{13}C$-NMR, NOE and CI-MS analyses were performed to elucidate the structures of the isolated compounds.