• Bulletin of the Korean Chemical Society
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• 제18권8호
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• pp.890-895
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• 1997

The approximate rates and stoichiometry of the reaction of excess lithium tripiperidinoaluminum hydride (LTPDA), an alicyclic aminoaluminum hydride, with selected organic compounds containing representative functional groups under the standardized conditions (tetrahydrofuran, 25°) were examined in order to define the reducing characteristics of the reagent for selective reductions. The reducing ability of LTPDA was also compared with those of the parent lithium aluminum hydride (LAH) and lithium tris(diethylamino)aluminum hydride (LTDEA), a representative aliphatic aminoaluminum hydride. In general, the reactivity of LTPDA toward organic functionalities is weaker than LTDEA and much weaker than LAH. LTPDA shows a unique reducing characteristics. Thus, benzyl alcohol, phenol and thiols evolve a quantitative amount of hydrogen rapidly. The rate of hydrogen evolution of primary, secondary and tertiary alcohols is distinctive. LTPDA reduces aldehydes, ketones, esters, acid chlorides and epoxides readily to the corresponding alcohols. Quinones, such as p-benzoquinone and anthraquinone, are reduced to the corresponding diols without hydrogen evolution. Tertiary amides and nitriles are also reduced readily to the corresponding amines. The reagent reduces nitro compounds and azobenzene to the amine stages. Disulfides are reduced to thiols, and sulfoxides and sulfones are converted to sulfides. Additionally, the reagent appears to be a good partial reducing agent to convert primary carboxamides into the corresponding aldehydes.

• 한국식품위생안전성학회:학술대회논문집
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• 한국식품위생안전성학회 2002년도 춘계학술발표대회 및 심포지움
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• pp.138-138
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• 2002

Oxidative stress has been associated with a number of diseases in human. Among the sources that can generate oxidative stress, it has been reported that iron can generate reactive oxygen species (ROS)with thiol. In iron overload state, increased thiol levels in plasma appeared to be associated with human mortality. In this study we examined whether iron could interact with thiols in plasma, generating ROS. In human plasma, unlike with Fe(III), Fe(II) increased lucigenin-enhanced chemiluminescence in concentration-dependent manner, and this was inhibited by SOD. Boiling of plasma did not affect chemiluminescence induced by Fe(II). Hovever, thiol depletion in plasma by pretreatment with N-ethylmaleimide (NEM)decreased Fe(II)-induced chemiluminescence significantly, suggesting that Fe(II) generated superoxide anion by the nonenzymatic reaction with plasma thiol. Consistent with this findings, albumin, the major thiol contributor in plasma, also generated ROS with Fe(II) and this generation was inhibited by pretreatment with NEM. Treatment with Fe(II) to plasma resulted un significant reduction of oxygen radical absorbance capacity (ORAC) value, suggest that total antioxidant capacity could diminished in iron overload state. In conclusion, In iron overload state, plasma may be affected by oxidative stress mediated by nonenzymatic reaction of Fe (II)with plasma thiol.

• Bulletin of the Korean Chemical Society
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• 제33권9호
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• pp.3076-3078
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• 2012

• Bulletin of the Korean Chemical Society
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• 제32권2호
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• pp.459-462
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• 2011

In the present work, catalytic activity of basic alumina in water has been demonstrated for the synthesis of poly functionalized pyridines. This strategy has some remarkable advantages, such as use of heterogeneous catalyst in aqueous media, reusability of catalyst and scalable approach.

• 한국생물물리학회:학술대회논문집
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• 한국생물물리학회 2002년도 제9회 학술 발표회 프로그램과 논문초록
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• pp.48-48
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• 2002

Glutathione (GSH) is most prevalent reducing thiols in eukaryotic cells and known that participates in many cellular processes. It was found that total amount of glutathione and the ratio of reduced to oxidized glutathione during development of Dictyostelium discoideum increase at the initial stage of the aggregation of amoeba.(omitted)

• Bulletin of the Korean Chemical Society
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• 제7권1호
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• pp.23-25
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• 1986

Reaction of ${\alpha}-cyano-{\beta}-phenylacrylic$ acid derivatives (Ⅰ) with thioglycolic acid in the molar ratio of 1:2 in saturated sodium bicarbonate solution yielded 3-(4'-oxo-2'-thiazolin-2'-yl)-2-phenyl-4-oxotetrahydrothiophene derivatives (V). Thioglycolic acid was found to be added not only to carbon-carbon double bond but also to carbon-nitrogen triple bond and those adducts were cyclized to V.

• Bulletin of the Korean Chemical Society
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• 제19권4호
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• pp.475-481
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• 1998

Details of various equilibria involved in the reactions of oxaza- and thiazazincolidine catalysts, generated from either β-amino alcohol or β-amino thiol, with aldehyde were studied by colligative measurements. The results indicated that the coordination of diethylzinc prior to the coordination of aldehyde is essential for high enantioselectivity of the thiol catalyzed reaction. The probable origin of asymmetric nonlinearity is also presented.

• Asian-Australasian Journal of Animal Sciences
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• 제31권6호
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• pp.905-913
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• 2018

Objective: To evaluate the effects of L-lysine (Lys)/L-arginine (Arg) on lipid and protein oxidation of emulsion sausage during storage and its possible mechanism. Methods: Four samples were prepared based on the presence or absence of additional sodium isoascorbate, Lys, or Arg: sample A (control), sample B (0.05 g of sodium isoascorbate), sample C (0.4 g of Lys), and sample D (0.4 g of Arg). Peroxide value (POV), thiobarbituric reactive substances (TBARS), protein carbonyls and thiols were measured. 2,2-Diphenyl-1-picrylhydrazyl (DPPH) and hydroxyl radical-scavenging, ferrous ion-chelating ability were also measured. Results: Compared with the control, the sample treated with sodium isoascorbate, Lys or Arg had significantly lower POV during the initial 20 days, TBARS during the initial 15 days. Protein carbonyls were significantly lower compared Sample B, C, and D with A during the later storage (10 to 25 days); basically, protein thiols became lower during storage when the samples were treated with sodium isoascorbate, Lys, or Arg. Both Lys and Arg had weak reducing power but strong ferrous ion-chelating activity and DPPH radical- and hydroxyl radical-scavenging activity. Conclusion: Both Lys and Arg effectively inhibited the oxidation of lipids and proteins in emulsion sausage by scavenging free radicals and chelating ferrous ions. The results obtained may be favorable for the prevention of lipid and protein oxidation during processing and storage of meat products.

• 대한화학회지
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• 제61권4호
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• pp.191-196
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• 2017

앞선 연구에서 TP(Thiolate-Protected)-나노은의 합성 시 초기에 형성되는 티올화 은 층간화합물의 형성을 막기 위하여 에탄올에 녹아있는 $NaBH_4$와 티올에 $AgNO_3$를 첨가하는 개선된 단일상 합성법을 보고하였다. 본 연구에서는 이 합성법을 보다 일반화하기 위하여 TP-나노금과 나노백금의 합성에 적용하였다. 합성된 생성물의 나노크기, 형상 및 금속에 부착된 티올의 배열은 UV-vis. 스펙트럼, 투과 전자 현미경 사진, X-선 회절 패턴 및 적외선 분광 스펙트럼을 이용하여 규명 하였다. TP-나노금과 나노백금은 구형 및 타원형의 형태를 하고 있으며 입자크기는 각각 약 3~7 nm와 약 2 nm 이하로 나타나고 있다. 한편 TP-나노금의 표면을 감싸는 옥탄티올 음이온의 메틸렌 사슬 [$-(CH_2)_7-$]의 메틸렌 배향은 trans임을 보여주고 있다.

• Archives of Pharmacal Research
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• 제27권5호
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• pp.531-538
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• 2004

Ginsan, a polysaccharide isolated from Panax ginseng, has been shown to be a potent immunomodulator, producing a variety of cytokines such as TNF-a, IL-1$\beta$, IL-2, IL-6, IL-12, IFN-${\gamma}$ and GM-CSF, and stimulating lymphoid cells to proliferate. In the present study, we analyzed some immune functions 1$^{st}$-5$^{th}$ days after ginsan i.p. injection, including the level of non-protein thiols (NPSH) as antioxidants, heme oxygenase (HO) activity as a marker of oxidative stress, zoxazolamine-induced paralysis time and level of hepatic cytochrome P-450 (CYP450) as indices of drug metabolism system, and activities of serum aspartate aminotransferase (AST), alanine aminotransferase (ALT), alkaline phosphatase (ALP), total bilirubin, and albumin level as indicators of hepatotoxicity. Ginsan in the dose of 100 mg/kg caused marked elevation (1.7-2 fold) of HO activity, decrease of total CYP450 level (by 20-34%), and prolongation of zoxazolamine-induced paralysis time (by 65-70%), and showed some differences between male and female mice. Ginsan treatment did not seem to cause hepatic injury, since serum AST, ALT, and ALP activities and levels of total bilirubin and albumin were not changed.d.