• Proceedings of the Korean Society of Soil and Groundwater Environment Conference
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• 2001.04a
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• pp.57-61
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• 2001

일반적으로 Asphaltene은 원유뿐만 아니라 화석연로원(Fessil Fuel Sources)에도 포함되어 있는 것으로 알려져 있으며 난분해성으로 탄화수소(Hydrocarbon)와 Heterocyclic 또는 N-, S-, 산소를 포함하는 화합물이다. 그리고 금속성 물질이 Asphaltene Fraction에 농축되어 있는 것으로 알려져 있다. 한편 이러한 metallo-complex는 Asphaltene의 구조화합물중 방향족계 sheet 사이에 Self-association 상태로 존재한다. Asphaltene의 분해는 일반 TPH나 BTEX계 유류의 분해 기작과는 매우 상이하며 현재까지 Asphaltene으로 오염된 토양의 복원 기술을 매우 미미한 것으로 알려져 있다. 따라서 본 연구는 Asphalteme으로 오염된 토양의 복원 기숙을 개발하기 위한 전단계로 Asphaletene의 구성물질과 저분자화 작용기작을 구명하여 효과적 복원기술 개발을 위하여 Arabian Light Oil에서 Oil 자체와 Oil에서 분리해낸 Asphaltene을 사용하여 용매조건과 처리제별로 저분자화 과정을 조사하였다.

• Proceedings of the Polymer Society of Korea Conference
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• 2006.10a
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• pp.230-230
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• 2006

Density functional theory (DFT) calculations using the B3LYP hybrid functional and the 6-311++G(d,p) basis set have been performed to predict the wavelength dispersion of optical absorbance and refractive indices for organic compounds and polymers in the range between the vacuum UV (${\sim}157\;nm$) and near-IR (${\sim}850\;nm$). The DFT calculations can reproduce the experimental dispersions of absorbance and refractive indices with high accuracy and low costs. The calculated dispersions demonstrate that the judicious introductions of $-F\;and\;-CF_{3}$ into alicyclic and heterocyclic compounds are effective in reducing the absorption at shorter wavelengths. In addition, the calculated Abbe numbers that represent the refractive index dispersion in the visble region are linearly proportional to the calculated refractive indices at 589 nm.

• Journal of the Korean Chemical Society
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• v.16 no.1
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• pp.33-39
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• 1972

The stabilization energies by interconjugations at the transition states in various Diels-Alder reactions were calculated. It has been found that the stabilization energies are inversely proportional to resonance energies of isolated molecules of polyene and heterocyclic system before reactions. It has been noted that the resonance energies of dienes are smaller than those of dienophiles in two different molecules. Therefore, the possibility of charge-transfer from dienes to dienophiles is hinted.

• Bulletin of the Korean Chemical Society
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• v.32 no.9
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• pp.3382-3388
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• 2011

Reaction of barbituric acid (BA), 1,3-dimethyl barbituric acid (DMBA) and 2-thiobarbituric acid (TBA) with cyanogen bromide and aldehydes in the presence of L-(+)-tartaric acid afforded a new route for the synthesis of stable heterocyclic 5-aryl-1H,1'H-spiro[furo[2,3-d]pyrimidine-6,5'-pyrimidine]2,2',4,4',6'(3H,3'H,5H)-pentaones which is a dimeric form of barbiturate (uracil and thiouracil derivative). In the reaction of 1,3-diethyl thiobarbituric acid (DETBA) the Knoevenagel condensation and then Michael adducts were obtained under the same condition. Structure elucidation is carried out by $^1H$ NMR, $^{13}C$ NMR, FT-IR and Mass analyses. Mechanism of the formation is discussed.

• Journal of the Korean Chemical Society
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• v.28 no.4
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• pp.244-250
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• 1984

Separation and identification of the polycyclic aromatic compounds (PAC) from pyrolysis products of cellulose and lignin were performed using a combination of acid-base solvent partitioning and silicic acid column chromatography with fused-silica capillary column gas chromatography/ mass spectrometry. Sixteen PAC were positively identifited by retention indices and mass spectra data. Both materials produced the same kinds of PAC. But lignin produced much more PAC than cellulose. Almost no highly carcinogenic heterocyclic PAC containing nitrogen and sulfur were produced.

• Bulletin of the Korean Chemical Society
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• v.31 no.9
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• pp.2633-2636
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• 2010

3-Acetyl-5-benzoyl-6-methyl-2-phenyl-4H-pyran-4-one has been subjected to condensation with a series of primary amines (ethylamine - octylamine) to clarify the proposed mechanism in our previous study. The reactions of the shorter amines of the series (ethylamine - butylamine) yielded unsymmetric pyridinone products, whereas the other amines (pentylamine - octylamine) yielded symmetrical pyridinones. The starting material and the products as well as the intermediates have been subjected to theoretical analysis by quantum chemical calculations at B3LYP/6-31G(d,p) level, which provided supporting data for the experimental findings.

• Archives of Pharmacal Research
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• v.12 no.3
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• pp.201-206
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• 1989

The reaction of acetoacetanilide (1) with the $\alpha$-cyanocinnamonitrile derivatives 2 yielded the Michael adducts 4 which could be converted into the pyrano [2, 3, -c] pyrazole derivatives 5 via their reaction with hydrazine hydrate. Cyclisation of 4 afforded the derivatives 10. The pyranopyrazoles 9 reacted with different activated nitrile derivatives (3a-c) to give the pyrano [2, 3-c] pyridine derivatives 13. 16 and 19 respectively. The biological activity of the synthesised heterocyclic derivatives was investigated and discussed.

• YAKHAK HOEJI
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• v.48 no.2
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• pp.141-146
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• 2004

Selective COX-2 inhibitors were expected to retain anti-inflammatory activity by inhibition of prostaglandin production with reduction of gastric and renal side effect associated with non-steroidal anti-inflammatory drugs. This study reported the syntheses of novel 2-thiohydantoin and hydantoin derivatives which have the structure of 5-membered heterocyclic ring substituted with two aryl groups, phenyl group at 5-position and p-sulfamylphenyl or p-methoxyphenyl group at 1-position. These synthetic compounds showed significant COX-2 activities in vitro screening. Among them, 5-phenyl-2-thiohydantoin and hydantoin substituted with benzyl group at 3-position, compounds 5 and 8, could be considered as lead compounds with $IC_{50}$/=13.13∼18.78 $\mu\textrm{g}$/$m\ell$ for the development of COX-2 inhibitors.

• Proceedings of the Korean Society of Dyers and Finishers Conference
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• 2009.03a
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• pp.138-139
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• 2009

• Natural Product Sciences
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• v.13 no.1
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• pp.27-32
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• 2007

Berberis tinctoria (Berberidaceae), commonly known as Nilgiri Barberry is a common allied species to B. aristata, used in India Traditional Systems of Medicine by the name of 'Daruharidra' for skin disease, jaundice, affection of eyes, and rheumatism. Keeping this in view, in the present study attempts have been made to identify marker characters of B. tinctoria. Some of the diagnostic features of the root are patches of pericyclic fibre, pitted sclerieds, crystals, berberine containing cells and heterocyclic medullary rays. Besides, the physicochemical characters such as total ash; acid insoluble ash; alcohol and water soluble extractive; tannins; sugar and starch percentages has also shown some variations. The percentage of berberine as berberine hydrochloride was also calculated through HPTLC densitometric method and it was found almost similar to B. aristata, B. asiatica and B. chitria i.e. 3.36%. Thus it can be explored as a possible source of substitute to B.aristata.