• 한국산학기술학회논문지
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• 제16권11호
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• pp.7555-7563
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• 2015

이온강도 0.10 M, $25^{\circ}C$ 수용액에서 Zn(II)이온과 2-(2-hydroxyethylamino)-2-(hydroxymethyl)-1,3-propa nediol(Monotris), Bis(2-hydroxyethyl)imino-tris(hydroxymethyl)methane(Bistris)과의 착물 형성을 전위차법으로 연구하였다. Zn(II)-Monotris 시스템에서 Monotris(L) 착물 $ZnL^{2+}$는 리간드의 히드록실 산소 원자 중에서 한 개의 산소 원자 뿐만 아니라 아민 질소가 배위되었다. 배위되어 있던 히드록실기의 수소 이온이 염기성 영역에서 해리되었다. Zn(II)-Bistris 시스템에서 Bistris(L) 착물 $ZnL^{2+}$는 리간드의 히드록실 산소 원자 중에서 두 개의 산소 원자 뿐만 아니라 아민 질소가 배위되었다. 배위되어 있던 히드록실기들 중 한 개의 히드록실기에서 수소 이온이 염기성 영역에서 해리되었다. 추가적으로 다른 한 개의 히드록실기에서 수소이온이 강염기 영역에서 해리되었다. $ZnL^{2+}$, $ZnLH_{-1}{^+}$, $ZnLH_{-2}$, $Zn_2L_2H_{-2}{^{2+}}$ 그리고 $Zn_2L_2H_{-3}{^+}$의 평형 상수값을 계산하였다.

• Toxicological Research
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• 제14권2호
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• pp.171-176
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• 1998

The biological effects of the water extracts of Rhus Verniciflua Stokes (RVS) were evaluated by protection against hydroxyl radicals. Antioxidative activities were measured using both 1,1-diphenyl-2-picrylhydrazyl (DPPH) and thiocyanate method. Also we used the Glucose oxidase (GO) 20 mU/$\textrm{m}{\ell}$ hydroxyl radical generating system in mouse forebrain cell culture. Water was used for ex-traction from RVS as a solvent which has high polarity especially. In DPPH method, the antioxidative activities of the crude water extract were stronger than any other extracts of low polar-solvents. In the antioxidative effects of mouse forebrain culture using 20 mU/$\textrm{m}{\ell}$ GO, cell viabilities were evaluated 65.6%, 68.8% at 1 $\mu\textrm{g}$. 5 $\mu\textrm{g}$ addition of crude water extracts (30 mg/$\textrm{m}{\ell}$) respectively. 10 $\mu\textrm{g}$ addition of crude water extracts had more than 86.1% cell viabilities, P<0.0l significantly, compared with the group treated with GO alone. In comparison with the antioxidative activities of several commercial antioxidants (ascorbic acid, $\alpha$-tocopherol, catalase, serum), 273 $\mu\textrm{g}$/$\textrm{m}{\ell}$ addition of crude water extracts (300 $\mu\textrm{g}$/$\textrm{m}{\ell}$) showed equivalent antioxidative effect to 25 uM ascorbic acid.

• 대한화학회지
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• 제56권2호
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• pp.246-250
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• 2012

An efficient access, single step and environmentally benign synthesis of a new series of pyrazole containing isoxazolines derivatives were prepared by the condensation of chalcones bearing pyrazole moiety with hydroxyl amine hydrochloride in basic condition by using polyethylene glycol-400 (PEG) as a greener reaction solvent. The advantages of the present methodology are mild reaction condition and avoidance of volatile organic solvent. Furthermore, these newly synthesized compounds were screened for their antimicrobial activity against various pathogens like Escherichia coli (MTCC 2939), Salmonella typhi (MTCC 98), Staphylococcus aureus (MTCC 96), Bacillus subtilis (MTCC 441), Aspergillus niger (MTCC 281), Aspergillus flavus (MTCC 2501), Penicillium chrsogenum (MTCC 160) and Fusarium moniliformae (MTCC 156). Especially compound containing the hydroxyl group in C2-position and presence of halo (I, Br and Cl) groups as substituents at $C_3$ and $C_5$ position on the benzene nucleus showed the higher activity. Furthermore, compounds bearing methyl groups in combination with I and Br which enhanced the activity.

• 한국식품영양과학회지
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• 제32권3호
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• pp.444-449
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• 2003

To investigate the long term effect of buchu (Chinese chives) diet on ROS formation in the liver and stin tissue of ICR mice, one of control, 2% or 5% buchu-added diet was fed to ICR mice for 12 months. Superoxide anion (O2ㆍ), hydrogen peroxide($H_2O$$_2$) and hydroxyl radical (ㆍOH) contents were measured in cytosol, microsome, mitochondria of liver and skin of mice, respectively. Behu diet showed a significant decrease of superoxide anion, hydrogen peroxide and hydroxyl radical contents in liver and skin tissues compared to control diet, and this effect is especially higer at 5% than at 2% buchu diet level. ICR mice showed an age-dependent increase in ROS contents, while the group fed buchu diet decreased its ROS contents significantly and ROS contents of liver appeared to be 2 fold higher than skin. The results of the present study suggest that antioxidative components and sulfur-compounds in buchu diet appear to be responsible for the inhibition of ROS formation in ICR mice.

• 공업화학
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• 제33권3호
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• pp.322-327
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• 2022

Fucoidans were degraded by hydrogen peroxide under the electron beam (2.5 MeV) with various radiation doses (5 kGy, 10 kGy, 15 kGy, and 20 kGy) at room temperature. The degradation property was analyzed with a gel permeation chromatography (GPC-MALLS) method. An average molecular weight of fucoidan decreased from 99,956 at the irradiation dose of 0 kGy to 6,725 at the irradiation dose of 20 kGy. The solution viscosity of fucoidans showed a similar pattern to the molecular weight change. The number of chain breaks per molecule (N) increased with increasing the irradiation dose and concentration of hydrogen peroxide. The radiation yield of scission value markedly increased with increasing the irradiation dose up to 15 kGy. Also a 10% hydrogen peroxide concentration was more efficient than that of 5%. The structures of degraded fucoidan samples were studied with Fourier transform infrared spectroscopy (FT-IR). The results showed that the degradation process did not significantly change the chemical structure or the content of sulfate group. The sulfur content of each sample was determined with an Elemental Analyzer. With increasing the concentration of hydrogen peroxide, the ratios of sulfur/carbon, hydrogen/carbon, and nitrogen/carbon slightly decreased. The antioxidant activities of fucoidans were investigated based on hydroxyl radical scavenging activities. The ability of fucoidan to inhibit the hydroxyl radical scavenging activity was depended on its molecular weight.

• 분석과학
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• 제17권5호
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• pp.401-409
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• 2004

7-keto-DHEA-acetate는 DHEA의 대사체인 7-keto-DHEA로 변하고 체내에서 대사되는 과정이 서로 유사하였으며 복용 후 검출된 대사체 M3, M4 및 M5에 대해 살펴보았다. 대사체 M3과 M4는 분자량이 304이며 물분자가 제거될 수 있는 히드록시기나 케톤기를 세 개 이상 가진 구조로 예상되었으며, M3의 경우 3번과 7번 탄소위치에 히드록시기가 있고 17번 탄소위치에 케톤기를 가지는 7-OH-DHEA이라는 것을 알 수 있었다. 대사체 M4는 3번과 17번 탄소위치에 히드록시기가 있고, 7번 탄소위치에 케톤기가 있는 구조인 7-oxo-diol 이었다. 대사체 M5는 분자량이 320이며 M3 및 M4와는 달리 물분자가 제거될 수 있는 히드록시기나 케톤기를 네 개 이상 가진 구조일 것이라고 예상되었으며, 3번과 7번 그리고 16번 탄소위치에 히드록시기가, 그리고 17번 탄소위치에 케톤기가 있을 것으로 예상되었다. 7-keto-DHEA-acetate 복용 후 최대 배설량을 보인 대사체는 7-OH-DHEA 이었으며, 복용 5시간 후 최대의 배설량을 보인 이후 급격히 감소하였으며 매우 빠른 속도로 체외로 배설되기도 하지만 복용 58시간 후의 뇨 시료에서도 검출되기 때문에 체내 잔류성이 높은 약물임을 알 수 있었다.

• 한국응용약물학회:학술대회논문집
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• 한국응용약물학회 1994년도 춘계학술대회 and 제3회 신약개발 연구발표회
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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.

• 생명과학회지
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• 제10권6호
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• pp.577-583
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• 2000

This study was designed to investigate the effect of silk fibroin (Mw 500)power (SFP) on oxygen radicals and their scavenger enzymes in liver membranes of rats. Sprague-Dawley (SD) male rats (160$\pm$10 g) were fed basic diet (control group), and experimental diets (SFP-2.5 and SFP-5.0 groups) added 2.5 and 5.0 g/kg BW/day for 6 weeks. Hydroxyl radical (.OH) levels resulted in a considerable decreases (5.8% and 8.4%, 3.7% and 11.1%, respectively) in liver motochondria and micorsomes of SFP-2.5 and SFP-5.0 groups compared with control group, and $O_2$radical level was remarkably decreased about 15% and 20% in liver cytosol of SFP-2.5 and SFP-5.0 groups compared with control group. Lipid peroxide (LPO) levels were significantly decreased (8.3% and 18.0%, 13.4% and 18.4%, respectively) in liver mitochondria and microsomes of SFP-2.5 and SFP-5.0 groups compared with control group. Oxidized protein (OP) levels were remarkably decreased about 11.6% in liver mitochondria of SFP-5.0 group compared with control group. Mn-SOD activities were remarkably in creased (17.6% and 28.8%, respectively) in mitochondria of SFP-2.5 and SFP-5.0 groups, and Cu/Zn-SOD activities were also effectively in creased (about 14.4%) in liver cytosol of SFP-5.0 groups, but significant difference between GSHPx activity in liver cytosol of these two groups could be not obtained. These results suggest that anti-aging effect of silk fibroin may play an effective anti-aging role in a aattenuating a oxidative stress and increasing a scavenger enzyme activity in liver membranes.

• 대한금속재료학회지
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• 제46권1호
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• pp.6-12
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• 2008

Peptides with specific sequences against $LaPO_4$ and $TiO_2$ nanoparticles were discovered through peptide phage display technique as an application to biomolecular recognition of inorganic materials. Sequencing results showed that a motif consisting of serine and proline was commonly expressed in specific sequences. It was postulated that serine directly bound to nanoparticles using its terminal hydroxyl (OH) group. In this sense, oxygen atom seemed to work as a ligand to metal ions and hydrogen atom as a H-bond donor, was thought to bind to the oxygen atoms or the hydroxyl groups on particle surface. Also, it was expected that proline assists serine to make an ideal van der Waals contact between serine and nanoparticles, which optimizes the binding of peptide onto surface.

• 대한화학회지
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• 제19권4호
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• pp.233-239
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• 1975

세개의 二重結合에 衣하여 conjugate된 비대칭화합물 cis-2-bitenedialdioxime의 두 oxime group의 configuration을 溶媒, 溫度 및 濃度의 影響에 대한 NMR 硏究로서 決定하였다. 溶液狀態에서의 이 化合物은 $-35^{circ}$∼$-95^{\circ}C$의 溫度條件下에서는 항상 "syn-syn" configuration으로 存在함을 알았다. 또한 이 化合物의 oxime group과 溶媒사이의 水素結合의 相對的强度와 溫度 및 濃度에 의 피리딘의 考察하고 몇가지 水素結合의 모델을 提示하였다. 特히 피리딘溶媒 속에서는 水素結合은 한 영향을 窒素가 갖고 있는 非共有電子雙에 衣해서 일어나지 않고, oxime 의 hydroxyl proton과 피리딘의 $\pi$軌道函數 사이에 形成되는 $\pi$-착물의 結果임을 알았다.