• Bulletin of the Korean Chemical Society
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• v.33 no.7
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• pp.2447-2449
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• 2012

• Bulletin of the Korean Chemical Society
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• v.34 no.1
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• pp.246-248
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• 2013

• Bulletin of the Korean Chemical Society
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• v.35 no.10
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• pp.3059-3062
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• 2014

Two new butyrolactones, asperphenol A (1) and B (2), together with four known butyrolactones (3-6) were isolated from the fermentation products of an endophytic fungus Aspergillus versicolor. Their structures were elucidated by spectroscopic methods including extensive 1D- and 2D-NMR techniques. Compounds 1-6 were also tested for their anti-tobacco mosaic virus (anti-TMV) activities. The results showed that compound 2 exhibited high anti-TMV activity with inhibition rate of 46.7%. The other compounds also exhibited potential anti-TMV activities with inhibition rates in the range of 21.8-28.4%.

• Bulletin of the Korean Chemical Society
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• v.34 no.11
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• pp.3257-3260
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• 2013

Two new diphenylethylenes, gramniphenols H and I (1 and 2), together with six known diphenylethylenes (3-8), were isolated from Arundina graminifolia. The structures of 1-8 were elucidated by spectroscopic methods including extensive 1D- and 2D-NMR techniques. Compounds 1 and 2 were evaluated for their cytotoxicity against five human tumor cell lines. Compound 1 showed cytotoxicity against PC3 cells with $IC_{50}$ value of 3.5 ${\mu}M$. Compound 2 showed cytotoxicity against NB4 and PC3 cells with $IC_{50}$ values of 3.6 and 3.8 ${\mu}M$, respectively.

• Bulletin of the Korean Chemical Society
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• v.34 no.4
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• pp.1263-1265
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• 2013

• Bulletin of the Korean Chemical Society
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• v.34 no.10
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• pp.3013-3016
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• 2013

Two new isoflavanones, (3R) 7,2',4'-trihydroxy-3'-methoxy-5-methoxycarbonyl-isoflavanone (1) and (3R) 7,2'-dihydroxy-3',4'-dimethoxy-5-methoxycarbonyl-isoflavanone (2), together with six known isoflavanones (3-8), were isolated from the stems of Cassia siamea. The structure of 1-8 was elucidated by spectroscopic methods including extensive 1D- and 2D-NMR techniques. Compounds 1, 2, 5-8 were evaluated for their anti-tobacco mosaic virus (Anti-TMV) activity. The results showed that compounds 1 and 6 showed potential anti-TMV activity with inhibition rates of 24.6% and 26.9%, respectively. Compounds 2, 5, 7, 8 also showed anti-TMV activity with inhibition rates in the range of 11.8-18.6%.

• Bulletin of the Korean Chemical Society
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• v.34 no.5
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• pp.1421-1424
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• 2013

Two new isoflavanones, (3R) 5,7,3',4'-tetrahydroxy-2'-methoxyisoflavanone (1) and (3R) 5',8-di-(${\gamma}$,${\gamma}$-dimethylallyl)-2',5-dihydroxyl-4',7-dimethoxyl-isoflavanone (2), were isolated from Uraria clarkei, together with two known compounds dalbergioidin (3), 5,7-dihydroxy-2',4'-dimethoxyisoflavanone (4). The structures involving the absolute configuration of the new compounds were well elucidated by MS, IR, UV, CD, 1D and 2D NMR analyses. Cytotoxicity of the four compounds were assessed, results suggested that compound 2 possessed well cytotoxic activity, against the Hela, K562, and HL60 cell lines with $IC_{50}$ values of 28.0, 40.6 and $35.1{\mu}M$, respectively.

• Bulletin of the Korean Chemical Society
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• v.34 no.3
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• pp.827-830
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• 2013

Investigation of an organic extract of the fruits Schisandra wilsoniana led to the isolation of two new highly oxygenated nortriterpenoids, named schilancidilactones V-W (1-2). Their structures were elucidated by spectroscopic evidence. Compounds 1-2 feature a double bond between C-7 and C-8 compared with related known nortriterpenoids isolated from the genus Schisandra. Compounds 1 and 2 were tested for their anti-HIV-1 activities and cytotoxicity. The results revealed that compounds 1 and 2 showed moderate anti-HIV-1 activities with $EC_{50}$ 3.05 and 2.87 ${\mu}g/mL$, respectively, and compound 1 showed high cytotoxicity against KB and MDA-MB-231 cell with $IC_{50}$ values of 3.18 and 5.22 ${\mu}M$, respectively.

• Journal of the Korean Geographical Society
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• v.42 no.4
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• pp.601-615
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• 2007

Many Korean migrants in Japan have established small businesses using their ethnic networks as they were discriminated and excluded from Japanese society and labour market. The aim of this study is to explore the changes in characteristics of Korean migrants' businesses by generation, focusing on the role of co-ethnic relationships including ethnic networks and resources on their businesses. This study analyzed Korean migrants' dependence of the ethnic resources to understand the relationship between the ethnic. When Koreans first moved to Japan, laborers amounted the most, but the number of the professionals and the small business owners has increased gradually. This change was influenced by the change of generation and the improvement of education, as well as recognition of Japanese society and the change of policies toward Korean migrants in Japan. In early times when the number of small business owners started to increase, many cases such as a business, an employment, the use of Korean banks used to depend on ethnic resources. Also there were many businesses of which main customers were Koreans. However, the dependence of the ethnic resources has become diverse as the structure of the occupation has changed. The maintenance or exclusion of co-ethnic relationship depends on the structure of society and economy, and its result affect the relationship between Korean migrants in Japan and Japanese.

• Journal of the Korean association of regional geographers
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• v.14 no.5
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• pp.507-520
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• 2008

The two districts, 'Xita' and 'Manrong' in Shenyang City, the cases of this study, form ethnic enclave economies revolving around small business enterprises run by Korean Chinese. This ethnic enclave economy appeared as Korean Chinese came to have 'double ethnic resources'-Korean Chinese and Koreans living in China, and to play the role of middlemen. This was helped by the Chinese government's encouragement(to attract the capitals of South Korea), and the experiences of Korean Chinese who had played in South Korea. This 'double ethnic enclave economy' has put Korean Chinese in a position where they cooperate with Koreans in China on the one hand, but are forced to compete with them on the other. For the development of a Chinese Korean economy, therefore, it is needed to enhance the cooperation with Koreans living in China within the ethnic enclave economies and at the same time to increase economic activities outside of the enclave economy.