• 한국생물공학회:학술대회논문집
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• 한국생물공학회 2000년도 추계학술발표대회 및 bio-venture fair
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• pp.638-639
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• 2000

Quinone reductase was purified to electrophoretic homogeneity from bovine liver by using ammonium sulfate fractionation, ion-exchange chromatography, and gel filtration chromatography. The enzyme utilized either NADH or NADPH as the electron donor. The optimum pH of the enzyme was pH 8.5, and the activity of the enzyme was greatly inhibited by $Cu^{2+}$ and $Hg^{2+}$ ions, dicumarol and cibacron blue 3GA. The enzyme catalyzed the reduction of several quinones and other artificial electron acceptors. Furthermore, the enzyme catalyzed NAD(P)H-dependent reduction of azobenzene or 4-nitroso-N,N-dimethylaniline. The apparent $K_m$ for 1,4-benzoquinone, azobenzene, and 4-nitroso-N,N-dimethylaniline was 1.64mM, 0.524mM and 0.225mM, respectively. The reduction of azobenzene or 4-nitroso-N,N-dimethylaniline by quinone reductase was strongly inhibited by dicumarol or cibacron blue 3GA, potent inhibitors of quinone reductase.

• 전기화학회지
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• 제5권4호
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• pp.216-220
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• 2002

The effects of electrolytes on electrochemical behavior from an oil thin layer interposed between a graphite electrode and an aqueous solution phase were examined. A hydrophobic electroactive species, tetrachloro-1,4-benzoquinone (TCQ), in a benzonitrile (EN) layer was employed to study ion transfer properties across the BN-water interface. Experimental results showed that hydrophobic cations as well as anions could be successfully used as ionic charge carriers. The addition of various salts into either the oil layers or the aqueous solutions offers deeper insight for the electrochemistry of the liquid thin layer system. When aqueous perchloric acid is interfaced with the BN films, the perchlorate ion of tetrahexylammonium perchlorate (THAP) substantially suppresses the dissociated proton concentration in the layer by the common ion effect while there is only a little change in the total acid concentration. Further approach by theoretical calculation makes it possible to quantitatively understand the effect of the electrolytes to the electrochemical responses of TCQ, which were previously reported (Anal. Chem. 73, 337 (2001)).

• Macromolecular Research
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• 제17권8호
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• pp.563-567
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• 2009

In order to improve the thermomechanical performance of polyketone, a third monomer (4-methylstyrene) was added to the copolymerization system. The terpolymer of CO, styrene, and 4-methylstyrene was synthesized in the presence of multi component catalysts containing palladium acetate and rare earth metal phosphonates. The products were characterized by infrared spectroscopy (IR), and nuclear magnetic resonance spectroscopy (NMR). The effects of the different components, including the third monomer, palladium acetate, 2,2'-bipyridyl, rare earth phosphonate, p-toluene-sulphonic acid, and p-benzoquinone, were also studied. The highest catalytic activity of 965.51 g/(gPd h) was obtained with a catalyst containing palladium acetate and rare earth phosphonate.

• 대한화학회지
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• 제37권7호
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• pp.648-654
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• 1993

$[M(cyclam)X_2]Y(M=Co^{3+},\;Fe^{3+},\;Mn^{3+}\;:\;X=Cl-^,\;Br^-,\;NCS^-\;:\;Y=Cl^-,\;Br^-,\;NCS^-),\;[Co(trans-14-diene)X_2]Y(X=Cl^-,\;Br^-\;:\;Y= ClO_4^-)$ 및 $[Co(trans-14-diene)](ClO_4)_2$ 착이온은 sodium borohydride 하에서 산소를 활성화시킬 수 있었다. 활성화된 산소에 의한 2,4-di-tert-butylphenol 과 2,6-di-tert-butylphenol 산화반응의 생성물질을 각각 2,4-tert-butyl-1,6-benzoquinone(BQ) 와 3,5,3',5'-tetra-tert-butyldiphenoquinone(DPQ) 이었다. BQ와 DPQ 생성반응에서 포화 거대고리 리간드 착물인 $[Co(cyclam)X_2]Y$은 불포화 거대고리착물 $[Co(trans-14-diene)X_2]Y$에 비하여 더 효과적인 촉매제이었다. 촉매로 작용한 Co(III)-거대고리착물과 산소간의 몰 결합비$(O_2/M)$는 1/1이었고, $[M(cyclam)Cl_2]Cl(M=Fe(III)$, Mn(III))에서는 이들 비가 1/2이었다. 반응(10)과 (2)에서 산소분자의 활성종은 Co(III) 거대고리착물이온과 $[M(cyclam)Cl_2]Cl(M=Fe(III)$, Mn(III))에서 각각 superoxolike$({O_2}^-)$와 peroxolike$({O_2}^{2-})$로 가정하였다.

• BMB Reports
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• 제33권4호
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• pp.321-325
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• 2000

Quinone reductase was purified to homogeneity from bovine liver by using ammonium sulfate fractionation, ionexchange chromatography, and gel filtration chromatography. The enzyme utilized either NADH or NADPH as the electron donor. The enzyme catalyzed the reduction of several quinones and other artificial electron acceptors. Furthermore, the enzyme catalyzed NAD(P)H-dependent reduction of azobenzene. The apparent Km for 1,4-benzoquinone and azobenzene was 1.64 mM and 0.524 mM, respectively. The reduction of azobenzene by quinone reductase was almost entirely inhibited by dicumarol or Cibacron blue 3GA, potent inhibitors of the mammalian quinone reductase. In the presence of 1.0${\mu}M$ Cibacron blue 3GA, azoreductase activity was lowered by 45%, and almost complete inhibition was seen above 2.0 ${\mu}M$ Cibacron blue 3GA.

• Archives of Pharmacal Research
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• 제28권5호
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• pp.509-517
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• 2005

A series of structurally diverse amide derivatives of [6-(3,5-dimethyl-4- chloro-pyrazole-1-yl)-3(2H)-pyridazinone-2-yl]acetic acid were prepared and tested for their in vivo analgesic and anti-inflammatory activity by using p-benzoquinone-induced writhing test and carrageenan induced hind paw edema model, respectively. The analgesic and anti-inflammatory activity of the compounds, 7c, 7d and 7k were found to be equipotent to aspirin (as an analygesic) and indometacin (as an anti-inflammatory drug), respectively. The other amide derivatives generally resulted in lower activity on comparision with reference compounds.

• 생명과학회지
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• 제12권3호
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• pp.281-287
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• 2002

소 간으로부터 퀴논 환원효소를 정제하였으며 정제된 효소는 벤조퀴논과 나프토퀴논 뿐만 아니라 페난트렌 퀴논의 환원도 촉매하였다. 소 간으로부터 정제된 퀴논 환원 효소는 아릴니트로소 화합물의 생변환을 촉매하였으며 반응 생성물은 TLC, GC, GC-MS, NMR을 사용하여 확인되었다. 이 반응은 포유동물 퀴논 환원효소의 강력한 저해제인 Cibacron blue 3GA나 dicumarol에 의하여 크게 저해되었다.

• Macromolecular Research
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• 제17권3호
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• pp.144-148
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• 2009

Poly(1-oxo-2-phenyltrimethylene) was synthesized by palladium-catalyzed copolymerization of styrene and carbon monoxide in quaternary ammonium ionic liquids. The $[Pd(bipy)_2][PF_6]_2$ compound had relatively more catalytic activity than $[Pd(bipy)_2][BF_4]_2$ in ionic liquids. The catalytic activity of palladium (II) composite catalyst was superior to the catalyst formed in situ from palladium acetate, 2,2-bipyridyl, and $X^-$ ($X^-=PF_6^-$, $BF_4^-$) in ionic liquids. The effects of the volume of ionic liquids, reaction time and benzoquinone content on the copolymerization were also described.

• 멤브레인
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• 제28권4호
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• pp.265-270
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• 2018

이전 연구에서 올레핀/파라핀 분리를 위해 poly(ethylene oxide)(PEO)/Ag nanoparicles (AgNPs)(전구체$AgBF_4$)/p-benzoquinone (p-BQ) 복합막이 제조되었으며, 이 복합체 분리막의 성능은 100시간까지 선택도 10과 투과도 15 GPU로 유지되는 것이 확인되었다. 하지만 전구체인 $AgBF_4$의 가격이 고가이기 때문에, 본 연구에서는 가격 측면에서 경쟁력이 있는 $AgNO_3$를 Ag nanoparticles의 전구체로 사용하여 실험을 진행하였다. 그 결과 이미 존재하고 있는 $NO_3{^-}$가 AgNPs를 감싸고 있기 때문에 분리 성능이 나오지 않는 것으로 관찰되었다. 이번 연구에서는 $AgNO_3$를 Ag nanoparticles의 전구체로 사용하여도 높은 성능을 내기 위해 전자수용체 7,7,8,8-tetracyanoquinodimethane (TCNQ)를 사용하여 PEO, polyvinyl alcohol (PVA), polyether block amide-1657 (PEBAX-1657) 고분자 복합막을 제조한 결과, 고분자와 전자수용체의 영향과는 무관하게 분리성능을 내지 못하는 것으로 분석되었으며, 이는 분리성능에 전구체의 음이온이 결정적 역할을 하는 것으로 분석되었다.

• 약학회지
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• 제49권6호
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• pp.443-448
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• 2005

Diosgenin (25 (R) - spirost-5-en-3$\beta$ -ol) was oxidized with 2,3-dichloro -5,6-dicyano-1,4-benzoquinone to form 25(R)-1,4,6-spirostatrien-3-one (1) as rigid cyclic $\alpha$,$\beta$-unsaturated carbonyl compound. This compound was reacted with $H_{2}O_{2}$, m-chloroperoxybenzoic acid (mCPBA), NaOCl in the presence with (R,R)- or (S,S)-Jacobsen catalyst, tert-butyl-hydroperoxide (TBHP) in Mo$(CO)_{6}$, and in VO $(acac)_{2}$ catalyst, respectively, 25(R) -1,4,6-spirostatrien -3-one (1) was reduced with $NaBH_{4}$ L-Selectride, $LiAIH_{4}$,$BH_{3}$ $\cdot$$(CH_{3})_{2}S$, Superhydride, Red-Al, and lithium tri-tert-butoxyaluminium hydride. And 25(R)-4,6-spirostadien-3$\beta$-ol (4) was treated with $H_{2}O_{2}$, mCPBA, TBHP in D - (-) - and L-(+)-diisopropyltar-trate and $Ti(OiPr)_{4}$ condition (Sharpless asymmetric epoxidation), TBHP in $Mo(CO)_{6}$, and in $VO(acac)_{2}$ catalyst, respectively.