• Applied Chemistry for Engineering
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• v.10 no.1
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• pp.93-97
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• 1999

In order to lower the surface energy of unsaturated polyester(UPE) resin, small amount of siloxane-ester copolymers were incorporated. The copolymers were synthesized by a condensation polymerization using ethylene glycol and hydroxy termintated polydimethylsiloxane as diols and maleic anhydride and phthalic anhydride as dibasic acids. The modified UPE resin surface was characterized by dynamic contact angle (DCA), peel strength measurements of pressure sensitive adhesives and X-ray photoelectron spectroscopy(ESCA). As the copolymer content in the blend and PDMS content in the copolymer are increased, both advancing and receding contact angles against water are increased. The strength required to peel-off the pressure sensitive adhesive tape from the modified UPE resin decreased dramatically with the addition of the copolymer. ESCA results indicated that polydimethylsiloxane segments are predominated at the outer surface of the modified UPE resin.

• Proceedings of the Korean Society of Applied Pharmacology
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• 1994.04a
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• pp.222-222
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• 1994

목적하는 화합물인 2',5'-dihydroxy-3'-무치환 유도체(1)는 uridine을 sodium metaperiodate로 산화하여 dialdehyde를 얻은다음 1,2-dianilinoethane으로 3'-aldehyde만을 선택적으로 보호, 2'-aldehyde를 NaBH$_4$로 환원, alcohol로 하여 deprotection 하므로서 hemiacetal율 얻는다. 이 hemiacetal을 TsSNHHNH$_2$로 처리하여 목적하는(1) 화합물을 얻었으며 2-azido-5-Hydroxy-3'-무치환 유도체(2)는 (1)화합물 합성시 얻은 hemiactal을 출발 물질로 하여 먼저 TBDPSCl로 silyaltion하여 5'-hydroxyl group을 보호하고 TsNHNH$_2$로 3'-위치를 hydrazone으로 한다음 NaB(CNH$_3$로 처리하여 얻은 hydrazide를 NaOAc를 반응시켜 2'-hydroxy-3'-무치환-5'-silyl 유도체를 얻고 또한 2',3'-dihydroxy group을 tosyl화, azido화, 5'-silyl group을 deprotection 하므로서 (2)를 얻었다. 또한 2',3'-dihydroxy-5'-무치환 유도체(4)는 uridine의 2',3'-위치를 먼저 protection, 5'-위치를 benzoyl화 2',3'-deprotection, periodate oxidation하여 얻은 diol을 silyl화 한 다음 5'-위치를 benzoyl화, 2',3'-deprotection, 산화하여 얻은 hemiacetal의 silyl group을 제거한후 primary hydroxyl group만을 선택적으로 silyl화, TsNHNH$_2$, NaB(CN)H$_3$ 및 NaOAc로 처리하므로서 얻은 2'-hydroxy-3'-0-silyl group-5'-무치환 화합물을 tosyl, azido화 한다음 desilylation하여 얻었다. 목적하는(1) 화합물의 diasteromer 인 2',3'-dihydroxy-5'-무치환 유도체(3)는 (4)화합물 합성시 얻은 hemiactal을 key intermediate로 하여 TsNHNH$_2$, NaB(CN)H$_3$ 및 NaOAc로 처리하므로서 얻을수 있었다. 이들 화합물들의 각종 DNA 및 RNA virus에 대한 항 바이러스작용을 검토한 결과 현저한 항 바이러스 작용을 나타내지 않았다.

• Applied Biological Chemistry
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• v.25 no.4
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• pp.211-217
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• 1982

Ginsenosides in epidermis·cortex(EC) and xylem-pith(XP) of main body of Panax ginseng(var. atropurpureacaulo) root were investigated in relation to dark purple area on stem. Pattern of ginsenosides, ratio of protopanaxatriol(PT) to diol(PD) and total ginsenoside content were significantly different between EC ana XP, and not related with stem color. The increasing trend of total ginsenosides with decreasing in purple area on stem needs to be tested with greater sample size. The order of ginsenoside content was $Rb_1>Rg_1>Re>Rc>Rg_2>Rb_2>Rf>Rd$ for EC, $Rg_1>Rb_1>Rg_2>Re>Rb_2>Rc>Rf>Rd$ for XP. PT/PD was 1.08 for EC,1.95 for XP. Since total ginsenoside content was 3 times higher in EC than in XP and weight of two parts was almost same, the content of ginsenosides of main body mostly depends on those of EC.

• Applied Biological Chemistry
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• v.39 no.1
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• pp.84-88
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• 1996

To determine brassinolide in rice(Oriza sativa L.) using HPLC equipped with fluoresence detector, a highly sensitive fluorescence reagent. 1-cyanoisoindole-2-m-phenylboronic acid, was synthesized from the reaction of o-phthaldehyde, m-phenylboronic acid and KCN, then was reacted with brassinolide. The formation ratio of brassinolide boronate exhibited 90% up at the ratio of $20\;:\;1({\mu}g/{\mu}g)$ of 1-cyanoisoindole-2-m-phenylboronic acid and brassinolide respectively. The detection limit of brassinolide boronate with fluoresence detector was 0.16 ng. Brassinolide was detected in heading stage(biomass : 10 g) and panicle formation stage(biomass : 100 g) of the rice(Oryza sativa L.) with quantity of $0.8\;{\mu}g\;and\;0.2\;{\mu}g$respectively. However, brassinolide was not detected in blooming and elongation stage.

• Applied Biological Chemistry
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• v.36 no.4
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• pp.260-264
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• 1993

In order to determine the stability of ginseng components in this salt concentration when used to ginseng as additive ingredient of sauces or seasonings, we study on the content and charactristic of ginsenosides and changes in pH and color, ginseng tail and ginseng extract were treated with various concentration of NaCl solution. In this experiment, extract of ginseng tail were increased in pH as NaCl concentration were increased, but ginseng extract have not changed evidently. The both solution were decreased in color as the salt concentration were increased. Yield of n-butanol extract was decreased in 5% NaCl concentration, while it was increased in the above concentration, and ginseng extract was changed higher than ginseng tail. Ginsenosides content were increased in 5% NaCl concentration, both $ginsenosied-Rb_1$, $-Rb_2$, -Rc, -Rd of diol line and ginsenoside-Re of triol line and increased in above NaCl concentration. Especially ginsenoside-Re showed to sensitive response to the changes of the salt concentration.

• Journal of Ginseng Research
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• v.18 no.2
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• pp.95-101
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• 1994

Saponin of Panax ginseng (C.A. Meyer) is composed of Protopanaxatriol (PT) and Protopanaxa- diol (PD). We investigated the effects of PT and PD on the contractility and $^{45}Ca$ uptake in the pig coronary artery. Isometric tension in the helical strips and $^{45}Ca$ uptake in the ring strips were measured in the presence or absence of PT and PD. PT and PD did not affect the high K+ (40 mM)-induced contraction but relaxed the ACh-induced contraction in a dose4ependent manner (1~10 mg/dl). The vasorelaxing effect of PT on the ACh-induced contraction was more potent than that of PD. Those relaxations were partially suppressed by the rubbing of endothelium removal. ACh-induced contraction in the $Ca^{2+}$-free Tyrode's solution was suppressed by the pretreatment of PT or PD. Following the depletion of ACh-sensitive intracellular $Ca^{2+}$ pool, ACh-induced contraction was suppressed by the pratreatment of PT or PD. With the pretreatment of PT or PD, $^{45}Ca$ uptake by high K+ (43 mM) was not changed but that by ACh was suppressed in the pig coronary artery. From the above results, we suggested that the vasorelaxing effect of PT and PD of Panax ginseng was due to inhibition of intracellular $Ca^{2+}$ release, inhibition of $Ca^{2+}$ uptake via receptor-operated $Ca^{2+}$ channels and in part a release of vasorelaxing factor from endothelium in pig coronary artery.

• Archives of Pharmacal Research
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• v.28 no.1
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• pp.28-33
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• 2005

Seven diterpenes, four polyacetylenes, a lipid glycerol, and two sterols were isolated from the methylene chloride fraction of the root of Aralia cordata. Their chemical structures were determined as (-)-pimara-8(14), 15-dien-19-oic acid (2), pimaric acid (3), (-)-kaur-16-en-19-oic acid (4), 17-hydroxy-ent-kaur-15-en-19-oic acid (9), $7{\alpha}$-hydroxy-(-)-pimara-8(14), 15-dien-19-oic acid (10), $16\alpha$, 17 -dihydroxy-(-)-kauran-19-oic acid (11), 16-hydroxy-17-isovaleroyloxy-ent-kauran-19­oic acid (12), falcarindiol (5), dehydrofalcarindiol (6), dehydrofalcarindiol-8-acetate (7), falcarin­diol-8-acetate (8), alpha-mono palmitin (13), stigmasterol (1), and daucosterol (14) by the spectral evidences. These compounds were tested with COX-1 and COX-2 inhibition assays. This study found that compounds 2, 4, 5, 6, 7, 8, and 10 inhibited COX-1 dependent conversion of the exogenous arachidonic acid to $PGE_2$ in a dose-dependent manner with $IC_{50}$ values of $134.2{\mu}M$, $121.6{\mu}M$, $170{\mu}M$, $50.4{\mu}M$, $11.7{\mu}M$, $99.6{\mu}M$, and $69.6{\mu}M$, respectively. But, most of these compounds weakly inhibited COX-2 dependent $PGE_2$ generation. Among them, only compound 4 showed relatively significant inhibitory activity $(IC_{50}\;:\;127.6{\mu}M)$.

• Korean Chemical Engineering Research
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• v.52 no.3
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• pp.378-381
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• 2014

We studied the pasteurization effect of the microorganism involved in the water, using ion-exchanging filter made of the Radiation Induced Grafted Polymerization. This ion-exchanging filter is made by the graft polymerization of GMA, after irradiation of electron beam to the non-woven filter. Then, we made the ion-exchanging filter (EtA, DEA, SS) applying ion-exchanging base to the GMA filter. As a result, the density of the ion-exchanging base is shown as 2.38 mol/kg in case of EtA, 1.79 mol/kg in case of DEA and 0.75 mol/kg in case of SS. Through this filter made by this method, we measured the pasteurization power of E. coli. We found very high elimination rate such as log 4.65 in case of SS-dial filter, which is higher as 3.00 times in comparison with EtA, and 1.10 times in comparison with DEA. This data show the result is very excellent comparing with 3,000 CFU/ml. of city water treatment basis.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2002.07a
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• pp.177-180
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• 2002

Thickness dependence of crystallographic orientation of diol based sol-gel derived PZT(52/48) films on dielectric and piezoelectric properties was investigated The thickness of each layer by one time spinning was about 0.2 $\mu\textrm{m}$, and crack-free films was successfully deposited on 4 inches Pt/Ti/SiO$_2$/Si substrates by 0.5 mol solutions in the range from 0.2 $\mu\textrm{m}$ to 3.8 $\mu\textrm{m}$. Excellent P-E hysteresis curves were achieved without pores or any defects between interlayers. As the thickness increased , the (111) preferred orientation disappeared from 1$\mu\textrm{m}$ to 3 $\mu\textrm{m}$ region, and the orientation of films became random above 3 $\mu\textrm{m}$. Dielectric constants and longitudinal piezoelectric coefficient d$\_$33/, measured by pneumatic method were saturated around the value of about 1400 and 300 pC/N respectively above the thickness of 0.8 7m. A micromachined piezoelectric cantilever have been fabricated using 0.8 $\mu\textrm{m}$ thickness PZT (52/48) films. PZT films were prepared on Si/SiN$\_$x/SiO$_2$/Ta/Pt substrate and fabricated unimorph cantilever consist of a 0.8 fm thick PZT layer on a SiNx elastic supporting layer, which becomes vibration when ac voltage is applied to the piezoelectric layer. The dielectric constant (at 100 kHz) and remanent polarization of PZT films were 1050 and 25 ${\mu}$C/$\textrm{cm}^2$, respectively. Electromechanical characteristics of the micromachined PZT cantilever in air with 200-600 $\mu\textrm{m}$ lengths are discussed in this presentation.

• Natural Product Sciences
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• v.24 no.2
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• pp.132-138
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• 2018

Phytochemical investigation of 80% MeOH extract of the aerial parts of Capsella bursa-pastoris yielded fourteen compounds (1 - 14). The structures of the compounds were elucidated by spectroscopic methods to be methyl-1-thio-${\beta}$-D-glucopyranosyl disulfide (1), 10-methylsulphinyl-decanenitrile (2), 11-methyl-sulphinyl-undecanenitrile (3), 1-O-(lauroyl)glycerol (4), phytene-1, 2-diol (5), (3S,5R,6S,7E)-5,6-epoxy-3-hydroxy-7-megastigmen-9-one (6), loliolide (7), ${\beta}$-sitosterol (8), 3-hydroxy-1-(4-hydroxy-3-methoxyphenyl)-1-propanone (9), 1-feruloyl-${\beta}$-D-glucopyranoside (10), pinoresinol-4'-O-${\beta}$-D-glucopyranoside (11), luteolin (12), quercetin-3-O-${\beta}$-D-glucopyranoside (13), and luteolin 6-C-${\beta}$-glucopyranoside (14). Although compound 1 was reported as synthetic compound, 1 was first isolated from natural source. NMR spectral data assignments of 1, 2 and 3 were reported for the first time, and compounds 1 - 14 were for the first time reported from this plant source. The anti-inflammatory effects of 1 - 14 were evaluated in lipopolysaccharide (LPS)-stimulated murine microglia BV-2 cells. Compounds 12 exhibited strong inhibitory effects on nitric oxide production in LPS-activated BV-2 cells with $IC_{50}$ values of $9.70{\mu}M$.