• Rubber Technology
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• v.9 no.1
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• pp.1-12
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• 2008

Effects of silane modifier, bis(triethoxysilylpropyl) tetrasulfide (TESPT(S4)) and bis(triethoxysilylpropyl) disulfide (TESPD(S2)), on silica filled compound were investigated upon processability, dynamic, mechanical, heat build-up, blowout properties, and silica dispersion in natural rubber (NR). The temperature of the S2 treated silica compound generated higher than that of the S4 treated compound during internal mixer compounding. The shear viscosity of the S2 compound exhibited lower than that of the S4 compound and the viscosity measured in dynamic mode was close to each other. The elongation modulus of the S2 compound exhibited lower than that of the S4; however, the tear resistance strength of the S2 compound exhibited higher than that of the S4 compound. The loss tan$\delta$ values of the S2 compound exhibited higher than those of the S4 at room temperature. The augmentation of the test temperature lowered the tan$\delta$ values of each compound, which results in close tan$\delta$ values to each other at $100^{\circ}C$. The S2 compound deformed less than the S4 compound, and the blowout time of each compound was close to each other. The S2 compound generated more heat build-up than the S4 compound. The abrasion loss of the S2 compound was less than that of the S4 compound. The size of the silica agglomerate reduced on both S4 and S2 compounds upon vulcanization. The addition of the bifunctional silanes (S2 and S4) on silica filled NR compound improved the processability of each compound and their effects were more significant on the S2 compound than the S4 compound. After vulcanization the silica agglomerate size of each compound reduced compared with before vulcanization.

• The Korea Journal of Herbology
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• v.21 no.2
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• pp.143-150
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• 2006

Oriental pear was used as treatment of asthma, control of blood pressure tonic medicine diabetes in oriental medicine, Pear Pectin was effective on control of blood pressure in previous report. In this study, it was investigated that Woohwang with pear extractions effects on cardiovascular system as blood pressure and renin and Atrial natriuretic peptide(ANP) in plasma. The 2K1C hypertension model was prepared by constricting the left renal artery with a sliver dip. Animals were then divided into three groups, control, Woowhang:Pear Phenolic compound(1:1), Woowhang:Pear Phenolic compound(2:1),Woowhang:Pear Phenolic compound(1:2) were supplied with them. Direct-blood pressure was measured at femoral vein, Indirect-blood pressure was measured at rodent tail. The results are as follows. The blood pressure was more significantly decreased at 1:2(woohwang:pear phenolic compound)group than other groups. On 6,9,12,15days, the blood pressure was significantly decreased in 1:2(woohwang:pear phenolic compound)group. The plasma ANP was significantly increased in 1:2(woohwang:pear phenolic compound)group. It tenders to decrease in 1:2(woohwang:pear phenolic compound)group on plasma renin. Based on the above results it is assumed that oral administration of Woohwang with Pear Phenolic compound(1:2) can help the treatment of hypertension.

• Proceedings of the Korean Society of Applied Pharmacology
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• 1993.04a
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• pp.118-118
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• 1993

퀴놀론 모핵의 합성은 기존에 알려진 합성 방법인 Could-Jacobs방법과 Bayer방법에 의해서 Intermediate로 사용된 7-chloro-1-ethyl-6-fluoro-1, 4-dihydro-4-oxoquinoline-3-carboxylic acid와 1-cyclopropyl-7-chloro-6-Fluoro-1,4-dihydro-4-oxoquinolne-3-carboxylic acid를 합성하였다. Heteroaromatic tin compound는 furan, thiophene, 3-bromopyridine, 2-fluoropyridine에 n-BuLi을 사용하여 metallation 한후 electrophile로 tributyltin chloride를 사용하여 2-tributylstannofuran, 2-tributylst-annothiophene, 3-tributylstannopyridine, 2- fluoro-2-tributylstannop-yridine을 합성할 수 있었다. 이상의 Intermediate와 tin compounds를 p-alladium 촉매하에서 반응시켜 1-ethyl-7-(2-furanyl)-6-fluoro-1,4-dihy-dro-4-oxo-3-quinoline-carboxylic acid (compound 3), 1-ethyl-7-(2-th-iophenyl)-6-fluoro-1,4-dihydro-4-oxo-3-quinol in carboxylic acid(compound 5), 1-ethyl-7-(3-pyridinyl)-6-fluoro-1,4-dihydro-4-oxo-3-quinoline carboxylic acid (compound 7), 1-ethyl-7-(2-fluoro-3-pyrid-nyl)-6-fluoro-1,4-dihydro-4-oxo-3-quinoline carboxylic acid (compound 9), 1-cyclopropyl-7-(2-furanyl) -6-fluoro-1,4-dihydro-4-oxo-3-quinoline carboxylic acid (compound 4), 1-cyclopropyl-7-(2-thiophenyl)-6-fluoro-1,4-dihydro-4-oxo-3-quinoline carboxylic acid (compound 6) ,1-cyclopropyl-7-(3-pyridinyl)-6-fluoro-1,4-dihydro-4-oxo-3-quinoline carboxylic acid (compound 8), 1-cyclopropyl-7-(2-fluoro-3-pyridinyl)-6-fluoro-1,4-dihydro-4-oxo-3-quinoline carboxylic acid (compound 10)를 합성하였다.

• Applied Biological Chemistry
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• v.41 no.1
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• pp.110-117
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• 1998

Seven kinds of polyphenol compounds having ACE activities were isolated and purified by Sephadex LH-20, MCI-gel CHP-20, ${\um}-Bondapak\;C_{18}$ and Fuji-gel ODS $G_3$ sucessively from cacao bean(Ghana). The chemical structures of each compound were determined and identified using analyzers such as $^1H-NMR$, $^{13}C-NMR$, IR, MS, polarimeter and Elemental Analysis. Inhibition effects of isolated polyphenols on angiotensin converting enzyme (concerned with hypertension) were also observed. The results obtained were as follows,; The compounds isolated and identified were confirmed and determined as compound 1 [(+)-catechin], compound 2 [(-)-epicatechin], compound 3 [procyanidin B-1 : (-)-epicatechin-$(4{\beta}{\rightarrow}8)$-(+)catechin], compound 4 [procyanidin B-2 : (-)-epicatechin-$(4{\beta}{\rightarrow}8)$-(-)-epicatechin], compound 5 [procyanidin B-7 : (-)-epicatechin-$(4{\beta}{\rightarrow}6)$-(+)-catechin], campound 6 (procyanidin B-2,3,3'-O -digallate), compound 7 [cinnamtannin A-2 : (-)-epicatechin-$(4{\beta}{\rightarrow}8)$-(-)-epicatechin-$(4{\beta}{\rightarrow}8)$-(-)-epicatechin-$(4{\beta}{\rightarrow}8)$-(-)-epicatechin]. In the inhibition effect on ACE, procyanidin B-2,3,3'-O-digallate (compound 6) showed a higher value of 94.6% for ACE in $100\;{\um}M$ than other compounds such as (+)-catechin (compound 1), (-)-epicatechin (compound 2), procyanidin B-1 (compound 3), procyanidin B-2 (compound 4), procyanidin B-7 (compound 5) and cinnamtannin A-2 (compound 7) showing 67.9%, 61.9%, 88.6%, 82.5%, 72.2% and 82.3% for ACE, respectively. Inhibition of $4{\beta}{\rightarrow}8$ in coupling bond on the ACE enzyme was more effective than that of $4{\beta}{\rightarrow}6$. Procyanidin containing gallate inhibited more effectively than those containing not any. It was also observed that a lot of hydroxy group in the compounds increased the inhibitory effect.

• YAKHAK HOEJI
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• v.46 no.6
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• pp.369-374
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• 2002

Dilithiation of 4-(pivaloylamino)pyridine (5) followed by reaction with tetraisopropylthiuram disulfide(TITD) gave rise to 3-(diisopropyldithiocarbamato)-4-(pivaloylamino)pyridine (6). 3-Mercapto-4H-pyrrolopyridine(2) was synthesized from compound 6 by two methods. The first method was that compound 6 was treated with 5M-HCl to form 2-t-butylthiazolo[5,4-c]pyridine (7) and hydrolysed in refluxing 10％ NaOH and solid NaOH to prepare bis(4-amino-3-pyridyl)disulfide (8). And compound 8 was reacted with 2,5-dimethoxytetrahydrofuran and NaBH$_4$ to afford compound 2. The second method was that compound 6 was hydrolysed with 10％ NaOH and followed to react with 2,5-dimethoxytetrahydrofuran to form compound 11. And then compound 11 was treated with 20％ ethanolic KOH solution to synthesize compound 2.

• Mycobiology
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• v.37 no.1
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• pp.31-36
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• 2009

A phytochemical study on the flower of Calotropis gigantea (Linn.) using silica gel column chromatography and preparative thin layer chromatography, led to the first time isolation of Di-(2-ethylhexyl) phthalate (compound 1) and anhydrosophoradiol-3-acetate (compound 2). The structures of these compounds were confirmed by spectroscopic analyses (IR, HRTOFMS and NMR). The antibacterial and antifungal activities of ethyl acetate extract, compound 1 and compound 2 were measured using the disc diffusion method. Ethyl acetate extract and compound 1 presented better results than compound 2. The minimum inhibitory concentrations (MICs) of the extract and compounds were found to be in the range of $16{\sim}128{\mu}g/ml$. The cytotoxicity ($LC_{50}$) against brine shrimp nauplii (Artemia salina) were also evaluated and found to be 14.61 ${\mu}g/ml$ for ethyl acetate, 9.19 ${\mu}g/ml$ for compound 1 and 15.55 ${\mu}g/ml$ for compound 2.

• Natural Product Sciences
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• v.10 no.6
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• pp.347-352
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• 2004

When saponin extracts of dried ginseng and red ginseng were anaerobically incubated with human intestinal microflora, these extracts were metabolized to compound K and ginsenoside $Rh_2$, respectively. However, when these extracts were incubated with commercial lactic acid bacteria, these did not metabolize these ginsenosides to compound K or ginsenoside $Rh_2$. Among some intestinal bacteria isolated from human feces, Bacteroides C-35 and C-36 transformed these saponin extracts to compound K and ginsenoside $Rh_2$, respectively. These bacteria also transformed water extracts of dried ginseng and red ginseng to compound K and ginsenoside $Rh_2$, respectively, similarly with that of the saponin extracts. Among transformed ginsenosides, compound K and 20(S)-ginsenoside $Rh_2$ exhibited the most potent cyotoxicity against tumor cells.

• Proceedings of the SCSK Conference
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• 2003.09a
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• pp.741-762
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• 2003

Ginsenosides, the major active ingredients of ginseng, show a variety of biomedical efficacies such as anti-aging, anti oxidation and anti-inflammatory activities. To understand the effects of compound K (20-O-D-glucopyranosyl-20 (S)-protopanaxadiol), one of the major metabolite of ginsenosides on the skin, we assessed the expression level of ∼ 100 transcripts in compound K-treated HaCaT cells using cDNA microarray analysis. Compound K treatment induced differential expression of 21 genes, which have been reported to be involved in the organization of ECM structure as well as defense responses in human skin cells. One of the most interesting findings is 2-fold increase in hyaluronan synthase2 (HAS2) gene expression by compound K. We found that change in expression of HAS2 gene represents a specific response of HaCaT cells to compound K because hyaluronan synthase 1, 3 was not changed by treatment with compound K. We also demonstrated that the compound K effectively induced hyaluronan synthesis in human skin cells and hairless mouse skin. The human clinical study indicates that topical application of compound K-containing oil-in-water emulsion showed improvement of xerosis, wrinkle and fine lines in the aged skin. We concluded that compound K has anti-aging effects by the induction of HAS2 gene expression and following hyaluronan synthase.

• Korean Journal of Microbiology
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• v.54 no.2
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• pp.136-139
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• 2018

The inhibitory compound (Compound S) against Ralstonia solanacearum and its conversion product (Compound S') were isolated from the culture filtrate of Bacillus subtilis JW-1 using a series of chromatography procedures. The structures were elucidated as alanyl-L-${\beta}$-(2,3-epoxycyclohexyl-4-one)alanine and alanyl-L-${\beta}$-(2,3-dihydroxycyclohexyl-4-one)alanine, respectively on the basis of nuclear magnetic resonance spectral data, including $^1H$, $^{13}C$, $^1H-^1H$ correlation spectroscopy and heteronuclear multiple bond correlation spectroscopy. The compound S exhibited a broad antimicrobial activity against $G^+$, $G^-$ bacteria, Saccharomyces cerevisiae and Candida albicans. The activity loss of the conversion product revealed that the epoxy function was essential for activity of Compound S.

• Journal of the Korean Society for Heat Treatment
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• v.7 no.3
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• pp.206-218
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• 1994

In 50%$NH_3+Air+N_2$ atmospheres, the effect of air additions on the growth characteristics of the compound layer during oxynitriding at $570^{\circ}C$ for 2hr in carbon and alloy steels has been investigated. The ammount of apparent residual ammonia during oxynitriding has shown to be increased with air additions(9~36 Vol. %) and X-ray diffraction analysis of case oxynitreded has shown that the compound layer consist of ${\varepsilon}-Fe_{2-3}$(N, C) phase and ${\gamma}^{\prime}-Fe_4$(N,C) phase. In the case of carbon steels, the thickness of oxide layer, compound layer and porous layer and the amount of ${\varepsilon}-Fe_{2-3}$(N,C) phase in the compound layer were increased with additions of air in 50%$NH_3+N_2$ atmospheres. At the same gas composition, the thickenss of oxide layer, compound layer and porous layer in alloy steels showed slightly thin layer thickness compared to those of carbon steels and the ${\gamma}^{\prime}-Fe_4$(N,C) phase in the compound layer of alloy steels was found barely. Therefore, the most obvious effect of air addition in the gas nitriding atmosphere has been found to in crease further kinetics of nitriding reaction.