• Bulletin of the Korean Chemical Society
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• 제23권1호
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• pp.21-22
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• 2002

• KSBB Journal
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• 제21권1호
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• pp.54-58
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• 2006

본 연구의 목표는 새롭게 분리한 두 종의 균주 Microbacterium barkeri KCCM 10507과 Paenibacillus amylolyticus KCCM 10508 에서 분비되는 PVA 분해 효소의 특성을 알아보고자 하였다. 상기 두 종의 균주로부터 얻은 crude enzyme을 사용하여 PVA 분해 시험을 진행한 결과, SAO의 활성은 시험 시작 후2일 혹은 3일 후 최대를 보인 반면, BDH의 활성은 시험 내내 점차 증가하는 경향을 보였다 또한, 배지내에 PVA가 존재하면 이들 효소의 활성 이 유지되었으나, PVA가 배지에서 완전히 사라지게되면, PVA 분해 효소의 활성도 사라졌다. 배지에 다시 PVA를 주입하면 이들 효소의 활성이 다시 나타났다. 이 결과를 통해 상기 두 종의 효소는 PVA 분해와 밀접한 관계가 있음을 알 수 있었고, PVA는 SAO와 BDH의 활성에 의해 분해된다는 것을 알 수 있었다.

• Journal of Photoscience
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• 제7권3호
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• pp.111-114
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• 2000

Irradiation of 1,3-cyclohexanedione and p-benzoquinone in methanol gave 3-methoxycyclohex-2-en-1-one. Allyl derivative of the 1,3-diketone was prepared as enol from and irradiated in methanol in the presence of p-benzoquinone to give the same type of photoproduct, i.e., 2-allyl-3-methoxycyclohex-2-en-1-one. Allyldibenzoylmethane was synthesized and irradiated with p-benzoauinone in methanol but no remarkable amount of photoproduct was obtained.

• Journal of Photoscience
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• 제11권3호
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• pp.129-132
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• 2004

Photochemically stable dibenzoylmethane and curcumin were cleaved dramatically when they were irradiated in the presence of N,N-dimethylaniline in methanol with 300 nm UV light. Several products such as benzil, secondary product derived from 1,4-diphenyl-1,4-butanedione, and unidentified compound were observed from the photoreactions of dibenzoylmethane with N,N-dimethylaniline. It was also found that one of the primary fragments produced by irradiation of curcumin in methanol were coupled with N,N-dimethylaniline to give a new enone compound, i.e., 1-(4-dimethylaminophenyl)-4-(4-hydroxy-3-methoxyphenyl)-but-3-en-2-one, as the major product.

• 분석과학
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• 제17권4호
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• pp.337-346
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• 2004

근육강화제의 일종인 7-keto-dehydroepiandrosterone-acetate (7-keto-DHEA-acetate)를 투여시킨 후 사람의 뇨를 통해서 배설되는 대사체들을 확인하고 그 결과를 향후 도핑 검사에 있어서 금지 약물로 선정될 경우를 대비한 기초 연구를 진행하고자 하였다. 먼저 뇨 시료의 매트릭스로부터 7-keto-DHEA-acetate가 방해 없이 효과적으로 검출되는 것을 알아보았으며, 약물을 복용한 dosed urine에 배설되는 대사체를 검출하기 위하여 LC/ESI/MS와 GC/MSD를 사용하였다. 그 결과 바탕 뇨 시료에서 나타나지 않은 여러 개의 새로운 화합물들이 복용 뇨 시료에서 검출되었으며 이들을 M1, M2, M3, M4 및 M5로 구별 하였으며 이 결과들로부터 대사체 M1과 M2는 물분자가 제거될 수 있는 히드록시기나 케톤기를 세 개 이상 가진 구조일 것으로 예상되었다. M1의 경우, m/z 518 이 분자이온이라면 분자량이 302인 이 대사체는 3번과 17번 탄소 위치에 케톤기, 7번 탄소위치에서 히드록시기를 가지는 구조인 7-OH-androstendione이라고 예상 할 수 있었으며, M2의 경우에는 M1 대사체와 마찬가지로 m/z 518이 분자이온이라면 분자량이 302인 이 대사체는 3번 탄소 위치에 히드록시기가 있고 17번 탄소 위치에 케톤기를 가지며 7번 탄소위치에 케톤기가 있는 구조인 7-keto-DHEA로 판단되었다.

• Bulletin of the Korean Chemical Society
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• 제17권11호
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• pp.1023-1031
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• 1996

A new synthetic route for the lanthanum β-diketonate compounds via in-situ formed lanthanum alkyl complexes was developed in the process for the development of suitable MOCVD (metal-organic chemical vapor deposition) precursors of PLT, one of the promising material for the ferroelectric film. A series of lanthanum β-diketonate compounds were successfully synthesized by this method. This new method is found to have some merits; versatile method for almost every β-diketone, β-hydroxyketone, and β-hydroxyaldehyde, short reaction time, easy purification for high purity, moderate to high yield, and easy access to anhydrous compounds. In some cases, anhydrous oligomeric products fail to show the higher volatility. On the other hand, some lanthanum β-diketonates with aromatic groups such as La(1,3-biphenyl-l,3-propandione)3 are found to have favorable properties for a precursor of lanthanum oxide, one of major components of PLT, such as low melting point, and much higher decomposition temperature. A plausible pyrolysis mechanism is proposed by the TGA, where consecutive dissociation of R, CO, CH, C, and O fragments occurs.

• 대한화학회지
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• 제18권6호
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• pp.437-442
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• 1974

Cyclopentanone을 출발 물질로 하여 60%의 좋은 총 수득률로 pentacyclo ($5,3,0,0^{2,5},06{3,9},0^{4,8})-decane-6,10-dion을 합성하였다. Cyclopentanone 으로부터 그의 ethylene ketal(I)을 합성하여 pyridinium bromide perbromide로서 브롬화시키고 브롬화 ketal(II)을 다시 dehydrobromination 시켜 cyclopentadienone-ethylene ketal의 dimer를 합성하였다. Ethylene ketal의 dimer(III)를 다시 가수분해시켜 dicyclopentadiene-1,8-dione(IV)을 합성하고 이 diketone(IV)을 photochemical cyclization에 의하여 pentacyclo ($5,3,0,0^{2,5},06{3,9},0^{4,8})-decane-6,10-dione(V)을 합성하였다.

• Bulletin of the Korean Chemical Society
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• 제31권12호
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• pp.3632-3638
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• 2010

2-Iminopyrimidines (1a-e) and 2-thioxopyrimidine (2) were synthesized using the Biginelli three component cyclocondensation reaction of an appropriate $\beta$-diketone, arylaldehyde, and guanidine (for 1a-e) or thiourea (for 2). The electrochemical properties of the novel systems were investigated by CV and DPV. Moreover, B3LYP/6-31G(d,p) method was applied to the present structures in order to gather some structural and physicochemical data.

• Bulletin of the Korean Chemical Society
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• 제32권4호
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• pp.1221-1227
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• 2011

Ethyl pyruvate (EP) is known as a scavenger of reactive oxygen species (ROS) in the body through its role in the donation of diketone groups to metals to form an EP-metal complex. In order to develop a method for the quantification of EP in biological media, a sensitive and specific, high-performance liquid chromatographyelectrospray ionization-mass spectrometry (HPLC-ESI/MS) method is used to determine the EP-alkali metal ion binding species. The analyte was separated on a ZORBOX SB-C8 ($3.5{\mu}m$, $30mm{\times}2.1mm$ I.D.) column and analyzed in selected ion monitoring (SIM) mode with a positive ESI interface using the m/z 255 $[2M + Na]^+$ ion. The method was validated over the concentration range of $0.5-60.0\;{\mu}g$/mL under 1/9 (v/v) of acetonitrile/methanol solvent system with flow rate 0.05 mL/min. The limit of quantification (LOQ) was $0.5{\mu}g$/mL.

• Bulletin of the Korean Chemical Society
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• 제17권7호
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• pp.637-642
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• 1996

Preparation and properties of potential CVD (Chemical Vapor Deposition) precursors for the TiO2, a major component of the perovskite materials such as PT, PLT, PZT, and PLZT were investigated. Reactions between β-diketones and TiMe3, formed in situ failed to produce stable Ti(β-diketonate)3 complexes but a stable purple solid, characterized as (OTi(BPP)2)2 (BPP=1,3-biphenyl-1,3-propanedione) was obtained when BPP was used. Several new Ti(Oi-Pr)2(β-diketonate)2 complexes with aromatic or ring substituents were synthesized by the substitution reaction of Ti(OiPr)4by β-diketones and characterized with 1H NMR, IR, ICP, and TGA. Solid complexes such as Ti(Oi-Pr)2(BAC)2 (BAC=1.-phenyl-2,4-pentanedione), Ti(Oi-Pr)2(BPP)2, Ti(Oi-Pr)2(1-HAN)2 (1-HAN=2-hydroxy-1-acetonaphthone), Ti(Oi-Pr)2(2-HAN)2 (2-HAN=1-hydroxy-2-acetonaphthone), Ti(Oi-Pr)2(ACCP)2 (ACCP=2-acetylcyclopentanone), and Ti(Oi-Pr)2(HBP)2 (HBP=2-hydroxybenzophenone) were found to be stable toward moisture and air. Ti(Oi-Pr)2(ACCP)2 and Ti(Oi-Pr)2(HBP)2 were proved to have lower melting points and higher decomposition temperatures. However, these complexes are thermally stable and pyrolysis under an inert atmosphere resulted in incomplete decomposition. Ti(Oi-Pr)2(DPM)2 (DPM=dipivaloylmethane) and Ti(Oi-Pr)2(HFAA)2 (HFAA=hexafluoroacetylacetone) were sublimed substantially during the thermal decomposition. Pyrolysis mechanism of these complexes are dependent on type of β-diketone but removal of Oi-Pr ligands occurs before the decomposition of β-diketonate ligands.