• Bulletin of the Korean Chemical Society
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• 제31권4호
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• pp.1043-1046
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• 2010

• 대한화학회지
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• 제37권9호
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• pp.806-812
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• 1993

Cu(I)(${\beta}$-diketonate) 착화합물로서 $Cu(I)(hfac)PR_3$(P는 phosphine, R은 Me, Et, Bu를 나타낸다) 착물들을 비수용매에서 유리질 탄소전극과 탄소 microelectrode를 사용하여 이들 착물들의 전기화학적 성질을 조사하였다. 아세토니트릴 용액에서 순환 전압-전류법에 의한 $Cu(I)(hfac)PR_3$ 착물들의 환원과정은 최종생성물이 Cu(0)로 가는 1전자 반응으로 진행되었다. 탄소 microelectrode를 이용한 대시간-전류법에 의해서 이들 착물들이 1전자 반응으로 진행됨을 확인하였으며, 확산계수는 $4.5{\sim}6.7{\times} 10^{-6}cm^2$/sec값으로 나타났다.

• Reproductive and Developmental Biology
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• 제35권3호
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• pp.209-214
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• 2011

Although the function and utility of RNA transcripts derived from matured spermatozoa remains unclear, they might play important roles in the establishment of a paternal genome and subsequently embryo development. Herein, we investigated the expression of X-chromosome linked RNA transcripts in matured bovine spermatozoa. The total RNA was extracted from the matured spermatozoa, and then converted to cDNA. Autosomal genes (ACT-${\beta}$ and H-2A) and X-chromosome linked genes (ANT3, HPRT, MeCP2, RPS4X, XIAP, XIST and ZFX) were analyzed for the characterization of X-chromosome linked RNA transcripts and compared to female fibroblasts by RT-PCR. The transcripts of autosomal genes (ACT-${\beta}$ and H2A) and X-chromosome linked genes (ANT3, HPRT, MeCP2, RPS4X and ZFX) were not detected in spermatozoa. However, XIAP (X-linked inhibitor of apoptosis protein) and XIST (X-chromosome inactive-specific transcript, a kind of paternal imprinted gene) transcripts were detected in spermatozoa, and relative levels of XIAP and XIST transcripts were similar and 0.5-fold lower when compared to female fibroblasts, respectively. Based on the findings, it is summarized that the presence of RNA transcripts of XIAP and XIST in the isolated spermatozoa may imply their role in inhibition of apoptosis and induction of X-chromosome inactivation in embryo development.

• Journal of Ginseng Research
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• 제11권1호
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• pp.17-23
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• 1987

인삼에서 생리활성이 보고된 알카로이드 분획에 관한 성분연구의 일환으로 백삼 50kg으로부터 알카로이드 분획 2.6g(수율:$5{\times}10^{-3}$%)을 분리하였으며, $CHCl_3$/MeOH(10 : 1)의 전개용매로 TLC한 결과 약 13종 이상의 Dragendorff 시약에 양성인 spot들을 관찰 할 수 있었다. 인삼 종류별 비교에 있어서는 백삼, 홍삼 및 전칠인삼은 서로 별 차이가 없었지만 미국인삼에 있어 No.2(Rf 0.71), No.3(Rf, 0.68)등의 spot가 검출되지 않았다. 또한 백삼에서 1종의 알카로이드 성분을 순수분리하여 화학적, 분광학적인 방법으로 구조를 구명한바 $N_9$-formyl-1-methyl-$\beta$-carboline으로 동정하였다.

• Nuclear Engineering and Technology
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• 제46권2호
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• pp.247-254
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• 2014

A study on the superconducting RF linac is underway in order to increase the beam energy up to 1 GeV by extending the Proton Engineering Frontier Project (PEFP) 100-MeV linac. The operating frequency of the PEFP superconducting linac (SCL) is 700 MHz, which is determined by the fact that the frequency of the existing normal conducting linac is 350 MHz. A preliminary study on the beam dynamics showed that two types of cavities with geometrical betas of 0.50 and 0.74 could cover the entire energy range from 100 MeV to 1 GeV. An inductive output tube (IOT) based RF system is under consideration as a high-power RF source for the SCL due to its low operating voltage and high efficiency. As a prototyping activity for a reduced beta cavity, a five-cell cavity with a geometrical beta of 0.42 was designed and fabricated. A vertical test of the prototype cavity at low temperatures was performed to check the performance of the cavity. The design study and the prototyping activity for the PEFP SCL will be presented in this paper.

• 한국약용작물학회지
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• 제13권5호
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• pp.284-287
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• 2005

The flowers of Chrysanthemum boreale Makino were extracted with 80% aqueous MeOH, and the concentrated extract was partitioned with n-hexane, EtOAc, n-BuOH and $H_2O$. Two compounds from the n-hexane fraction and one glucoside from the n-BuOH fraction were isolated through the repeated silica gel and ODS column chromatographies. From the result of physico-chemical data including NMR, MS and IR, the chemical structures of the compounds were determined as ${\beta}-sitosterol$ (1), phytol (2) and zingerone $4-O-{\beta}-D-glucopyranoside$ (3). Compounds 2 and 3 were isolated for the first time from this plant.

• Natural Product Sciences
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• 제20권2호
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• pp.76-79
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• 2014

In our ongoing search for structurally interesting and biologically active metabolites from Korean wild mushrooms, bioassay-guided fractionation and a chemical investigation of the MeOH extracts of the fruiting bodies of the mushroom Naematoloma fasciculare resulted in the isolation of three ergosterol derivatives, (22E,24R)-ergosta-7,22-diene-$3{\beta}$,$5{\alpha}$,$6{\beta}$,$9{\alpha}$-tetrol (1), (22E,24R)-$5{\alpha}$,$8{\alpha}$-epidioxyergosta-6,22-diene-$3{\beta}$-ol 3-O-${\beta}$-$\small{D}$-glucopyranoside (2), and (22E,24R)-$5{\alpha}$,$8{\alpha}$-epidioxyergosta-6,9,22-triene-$3{\beta}$-ol 3-O-${\beta}$-$\small{D}$-glucopyranoside (3). The structures of 1 - 3 were determined by comparison of their spectroscopic and physical data with reported values. The isolated steroid derivatives 1 and 3 were reported for the first time from this mushroom. Compounds 1 - 3 were tested for their cytotoxic activities against four human cancer cell lines (A549, SK-OV-3, SK-MEL-2, and HCT-15).

• Journal of the Korean Wood Science and Technology
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• 제43권2호
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• pp.214-223
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• 2015

The bark of Acer komarovii was collected, ground, and extracted with 70% aqueous acetone to obtain concentrates. The concentrates were suspended in $H_2O$, and then successively partitioned with n-hexane, dichloromethane and ethylacetate to be freeze dried. A portion of ethylacetate fraction was chromatographed on a Sephadex LH-20 and a RP C-18 column with various aqueous MeOH-$H_2O$ (1:0, 1:1, 1:2, 1:5, 1:7, 1:9, 1:10, 3:1, and 4:1, v/v) eluents. Four compounds were isolated; (-)-epicatechin (9.6 g), procyanidin A2 (epicatechin-($4{\beta}{\rightarrow}8$, $2{\beta}{\rightarrow}O{\rightarrow}7$)-epicatechin) (1.3 g), procyanidin B2 (epicatechin-($4{\beta}{\rightarrow}8$)-epicatechin) (40.0 mg), and cinnamtannin B1 (epicatechin-($4{\beta}{\rightarrow}8$, $2{\beta}{\rightarrow}O{\rightarrow}7$)-epicatechin-($4{\beta}{\rightarrow}8$)-epicatechin) (690 mg). The analysis of the bark procyanidins showed that the basic unit constituting condensed tannins was only (-)-epicatechin. This study, for the first time, report the procyanidins of Acer komarovii bark.

• Journal of Applied Biological Chemistry
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• 제53권2호
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• pp.77-81
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• 2010

동부를 80% MeOH로 추출하고, 얻어진 추출물을 EtOAc, n-BuOH 및 $H_2O$로 용매 분획 하였다. 이 중 EtOAc과 n-BuOH 분획으로부터 silica gel과 octadecyl silica gel(ODS) column chromatography를 반복하여 4종의 sterol 화합물을 분리, 정제하였다. 각 화합물의 화학구조는 NMR, MS 및 IR 등의 spectrum data를 해석하여, stigmasterol(1a), $\beta$-sitosterol(1b), 7-ketositosterol(2) 및 stigmasterol 3-O-$\beta$-D-glucopyranoside(3)로 동정하였다. 화합물 1b, 2와 3은 동부에서 처음 분리되었다.

• Applied Biological Chemistry
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• 제48권1호
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• pp.98-102
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• 2005

꽃마리를 80% MeOH로 추출하고, 얻어진 추출물을 EtOAc, n-BuOH 및 $H_2O$로 용매 분획하였다. EtOAc와 n-BuOH 분획에 대하여 column chromatography를 반복하여 4종의 flavonol 배당체를 분리하였다. 각각에 대하여 2D-NMR을 포함한 스펙트럼 데이터의 해석과 문헌 자료를 조사하여 $kaempferol-3-O-{\beta}-{D}-glucopyranoside(astragalin),\;kaempferol-3-O-{\alpha}-{L}-rhamnopyranosyl(1{\rightarrow}6)-{\beta}-{D}-glucopyranoside(nicotiflorin),\;quercetin-3-O-{\alpha}-{L}-rhamnopyranosyl(1{\rightarrow}6)-{\beta}-{D}-glucopyranoside(rutin),\;quercetin-3-O-{\beta}-{D}-glucopyranoside(isoquercitrin)$로 구조를 결정하였다. 이 화합물들은 꽃마리에서는 이번에 처음 분리, 보고되었다. 또한 $nicotiflorin(100\;{\mu}g/ml)$은 hACAT1에 대하여 $68.3{\pm}1.2%$ 저해활성을 나타내었다.