• Korean Journal of Fisheries and Aquatic Sciences
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• v.32 no.2
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• pp.223-231
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• 1999

Carotenoid pigments of echiurid, Urechis unicinctus were investigated during March, April and May as a part of comparative biochemical studies of carotenoid pigments for the marine organisms other than pisces. Total carotenoid contents were found to be 1.19 mg/100 g in March, 0.98 mg/100 g in April and 0.84 mg/100 g in May, indicating that total carotenoid content was negatively affected by the temperature of sea water that echiurid resided. The carotenoid isolated in March composed of $16.3\%$ diatoxanthin monoester, $14.8\%$ $\beta$-carotene and $12.6\%$ cynthiaxanthin monoester, $8.4\%$ cynthiaxanthin diester, $8.2\%$ zeaxanthin monoester, $7.3\%$ diatoxanthin diester $4.2\%$ astaxanthin $2.9\%$ diatoxanthin, $2.4\%$ triol, $2.3\%$ cynthiaxanthin, $1.7\%$ isocrytoxanthin, $1.5\%$ zeaxanthin diester, $0.8\%$ zeaxanthin and $0.5\%$ lutein. The carotenoid isolated in April composed of $21.9\%$ diatoxanthin monoester, $17.2\%$ cynthiaxanthin monoester and $16.6\%$ $\beta$-carotene $10.9\%$ zeaxanthin monoester, $5.6\%$ cynthiaxanthin diester, $4.9\%$ diatoxanthin diester, $3.1\%$ astaxanthin, $2.4\%$ triol, $2.3\%$ diatoxanthin, $1.7\%$ isocrytoxanthin, $1.5\%$ lutein, $1.1\%$ zeaxanthin, $1.0\%$ cynthiaxanthin and $1.0\%$ zeaxanthin diester. Similarly, the carotenoid isolated in May composed of $25.3\%$ diatoxanthin monoester, $19.7\%$ cynthiaxanthin monoester, $13.0\%$ $\beta$-carotene, and $12.6\%$ zeaxanthin monoester, $5.8\%$ cynthiaxanthin diester, $5.1\%$ diatoxanthin, $3.0\%$ astaxanthin, $2.4\%$ triol, $2.2\%$ diatoxanthin, $1.3\%$ isocrytoxanthin, $1.2\%$ zeaxanthin, $1.1\%$ zeaxanthin diester, $1.0\%$ lutein and $0.9\%$ cynthiaxanthin. Based on these data, monoester-type carotenoids ($37.1\~57.6\%$) and diester-type carotenoids ($11.5\~17.2\%$) of total carotenoids in echiurid were the major carotenoids. Meanwhile, when the sea water temperature was elevated and the contents of total carotenoid in echiurids were decreased, the contents of zeaxanthin monoester, diatoxanthin monoester and cynthiaxanthin monoester were increased, but the contents of zeaxanthin diester, diatoxanthin diester and cynthiaxanthin diseter were decreased, indicating that changes in ester-type caroteoids were differently affected by the sea water temperature.

• Bulletin of the Korean Chemical Society
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• v.34 no.12
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• pp.3777-3781
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• 2013

A formal total synthesis of aliskiren was accomplished. A key in our synthesis was to use the symmetric ciscisoid-cis-bis-lactone 3' as a precursor, which was prepared from D-tartrate diester. Appending the end groups and functional group transformations completed the synthesis.

• Journal of the Korean Applied Science and Technology
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• v.23 no.3
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• pp.192-198
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• 2006

To provide an aqueous rust inhibitor for metalworking lubricant having low toxicity and excellent rust resistance, we synthesized diester of malonic acid by three consecutive esterifications with over 98% of conversion. This substituted malonic diester could be used as an additive to mineral oil based metalworking lubricant. These metalworking lubricant compositions were showed excellent rust resistance and suitable for various metals and different metalworking processes including hot rolling and cold rolling of aluminum and aluminum alloys.

• Bulletin of the Korean Chemical Society
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• v.22 no.6
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• pp.638-640
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• 2001

• Korean Journal of Fisheries and Aquatic Sciences
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• v.26 no.2
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• pp.91-101
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• 1993

To investigate the effects on pigmentation and carotenoid metabolism of red sea breams Pagrus major and flounders Paralichithys olivaceus by the supplemented carotenoids, fishes wire fed the diet each containing ${\beta}$-carotene, lutein ester, astaxanthin, astaxanthin monoester, astaxanthin diester and ${\beta}$-apo-8'-carotenal for 8 weeks. Carotenoids in the integuments were analyzed. In cultured red sea breams with supplemented carotenoids, carotenoid deposition and pigmentation were higher in order of astaxanthin diester group, ${\beta}$-apo-8'-carotenal group and astaxanthin monoester group. The main carotenoids of red sea breams were astaxanthin diester, tunaxanthin and ${\beta}$-carotene. Difference in the content of astaxanthin diester and ${\beta}$-carotene was observed from natural and cultured red sea breams. In cultured flounders with supplemented carotenoids, carotenoid deposition and pigmentation were higher in order of ${\beta}$-carotene group and lutein ester group. The main carotenoids of flounders were zeaxanthin and lutein. Difference in lutein and ${\beta}$-carotene contents was observed from the natural and cultured flounders. Based on the contents and composition of carotenoids in each group after feeding experimental diet, carotenoid metabolism in red sea breams were presumed the reductive metabolic pathway, astaxanthin to tunaxanthin, and likewise, in flounders, lutein to tunaxanthin.

• Journal of the Society of Cosmetic Scientists of Korea
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• v.23 no.2
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• pp.97-117
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• 1997

L-Ascorbic acid 및 그 유도체는 항산화 작용과 미백작용 및 섬유아세포의 생장 촉진과 콜라젠 생합성의 증가시키는 효과가 있으므로 화장품에서 오래 전부터 사용되어 왔다. 본 연구에서는 생체에 대한 안전성과 안정성이 우수한 L-Ascorbic acid 유도체를 개발하기 위하여 인지질과 유사하게 L-Ascorbic acid 에 3-Aminopropane phosphoric acid를 결합하여 L-Ascorbic acid-3-aminopropane phosphoric acid diester를 합성하였다. ASA-APPA 는 2-Chlorotetrahydro-2H-1, 3, 2-oxazaphosphorine P-oxide 와 5, 6-isopropylidene L-Ascorbic acid 를 반응 시킨 후 산 사수분해 반응을 통하여 얻을 수 있었다. ASA-APPA는 수용액에서 안정성이 우수하였으며, 독성실험에서 무독성 물질이며, 인체 첩포 실험에서도 무자극 물질임을 확인하였다. 그리고, ASA-APPA 는 L-Ascorbic acid 와 3-APPA 의 혼합물과 거의 유사한 섬유아세포의 증식효과를 나타내었으며, melanoma 에 대한 멜라닌 생성 억제 실험에서 L-Ascorbic acid phosphate magnesium salt 와 유사한 효과를 보였다. 따라서 ASA-APPA 는 멜라닌 생성 억제 효과와 섬유아세포의 증식 효과를 갖는 새로운 화장품 원료로서 사용이 가능할 것으로 생각된다.

• YAKHAK HOEJI
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• v.23 no.1
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• pp.1-6
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• 1979

The authors investigated the biodegradability and toxicity of polyoxyethylene-alkyl citric diester-triethanolamine(PAT), which is one of new non-ionic detergents. 1) The PAT is very biodegradable, which 50% is biodegraded for one day and 100% for eight days by the activated sludge treatment and 40% for one day and 93% for eight days by the aerobic domestic sewage treatment. 2) $LD_{50}$ of PAT for chicken, mouse, and rat by oral adminstration are 7.1g/kg, 8.4g/kg and 14.0g/kg reactively. 3) $TL_{m}$ of PAT for goldfish is 64.0mg/l in 24bours. 4) No reaction for humun skin is determined by PAT.

• Proceedings of the Korean Society of Tribologists and Lubrication Engineers Conference
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• 1993.04a
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• pp.112-117
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• 1993

최근의 급속한 산업발전에 의해 각종 기계나 내연기관의 운전조건이 가혹해 짐에 따라 윤활유의 물성도 점차 고성능화 되는 추세로 광유계윤활유에서 볼수 없는 높은 점도지수, 낮은 저온유동성, 우수한 화학적안정성등의 특성을 얻기 위해 유기합성방법에 의해 인위적으로 합성한 원료를 기유로 사용한 윤활유를 합성윤활유라 하며 합성기유는 작용기 종류, 합성방법에 다라 다양하게 분류된다. 합성윤활유의 종류에는 일반적으로 합성방법에 따라 폴리머형(P형)과 비폴리머형(N형)으로 대별되는데 폴리며형 합성에는 polybutene, polyalkyleneglycole, poly $\alpha$-olefin (PAO)와 diester가 주로 사용되고 있다. 본 연구에서는 그간 연구해온 광유계윤활유의 첨가제 합성, 혼련기술 및 PAO와 diester합성기술을 기초로 내연기관용 고성능 합성윤활유 혼련기술 개발과 더 나아가 항공기작동유나 Jet-engine유등 특수 윤활유 개발에 연구목적이 있다.

• Textile Coloration and Finishing
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• v.15 no.1
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• pp.48-55
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• 2003

As the polyester fiber becomes thinner, thermomigration that is the most important factor deteriorating the washfastness, is more dominant. For improving the washfastness of ultrafine polyester dyed with disperse dye, it is necessary either to decrease the amount of thermomigrated dyes on the fiber surface, or to use a disperse dye containing diester group in the coupling component. This paper is concerned to investigate the relation between the chemical structure of three disperse dyes and their dyeing properties and washfastness. The disperse dye whose molecular size is big, can dye ultrafine polyester with good build-up, and its washfastness is reasonably good. Other disperse dye which has diester group, shows the same dyeing properties as the standard disperse dye, and its washfastness is better than that of the standard disperse dye.

• Journal of Applied Biological Chemistry
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• v.49 no.3
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• pp.86-89
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• 2006

The novel tetranuclear nickel (II) complex is a high rate accelerator in promoting hydrolysis of phosphate diesters. Nickel-bound bis-nitrophenyl phosphate (BNPP) can be $10^4$ times more reactive than the unbound BNPP. The large rate of enhancements by the complex slightly under basic condition has shown high catalytic activity in phosphate diester cleavage. The bell-shaped pH-rate profile indicated that the nickel-oxide form of the tetranuclear complex or its kinetic equivalent was the active species for cleaving BNPP. The catalytic hydrolysis between tetranuclear nickel (II) complex and phosphate diester proceeds via the formation of bidentate coordination of the anionic phosphate to the Ni (II) atom. This reveals that the complex has the possibility as artificial nuclease.