• 분석과학
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• 제20권2호
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• pp.115-123
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• 2007

헤테로싸이클릭 아민류(heterocyclic amines, HAs)는 소고기, 돼지고기, 닭고기 그리고 생선과 같은 근육질의 육류를 조리 할 때 생겨나는 돌연변이원성/발암성 화학물질로 잘 알려져 있다. 식품으로부터 HAs의 분석에 있어 가장 큰 어려움은 HAs가 식품 중에 극히 미량(수 ng/g)으로 존재한다는 것과 많은 방해물질이 존재한다는 것이다. 식품으로부터 HAs를 추출하고 정제하기 위해 고체-상 추출(solid-phase extraction, SPE)이 많이 사용되고 있다. HAs 분석을 위해 여러 단계의 SPE 과정을 수행하였다. HAs의 회수율은 표준물질이 녹여져 있는 메탄올 수용액과 조리되지 않은 돼지고기에 표준용액을 스파이크하여 서로를 비교하여 얻었다. 회수율은 25.0 ng/g에서 25.3~93.0%의 값을 얻을 수 있었다. 확립된 감도 좋고 재현성있는 시료전처리방법을 통해서 ${\mu}$-LC/ESI-MS에 주입함으로써 조리된 육류로부터 HAs를 분석하는데 응용될 수 있을 것이다. 다른 방법으로는 freezing filtration 방법으로써 보다 좋은 추출 효율과 재현성을 나타내었다.

• 약학회지
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• 제45권4호
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• pp.321-327
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• 2001

The synthesis of novel taxol analogues with an amine moiety at the 7- and 10-positions to examine the BBB penetration was described. The analogues were synthesized from 2'-O-(tert-butyldim-ethylsilyl)taxol and 2'-0-(tert-butyldimethylsilyl) -7-O-(triethylsilyl)-10-deacetyltaxol, the key intermediates, in 2 steps via the esterification with heterocyclic amino acids and the subsequent desilylation reaction.

• Bulletin of the Korean Chemical Society
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• 제34권5호
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• pp.1325-1326
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• 2013

• 분석과학
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• 제11권4호
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• pp.292-296
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• 1998

헤테로 고리 화합물인 isoquinoline과 외부치환체로서 $COOCH_3$, CN 및 $CH_3$ 작용기들이 치환된 화합물들의 혼합물을 정상 및 역상법으로 분리 한 결과, 이동상의 종류에 따라 용리순서에 용매화 효과가 나타났다. 또한, 헤테로 고리 화합물 내부의 방향족성이 없는 2-methylindoline과 방향족성이 있는 2-methylindole, 그리고 헤테로 원자가 질소와 산소인 benzoxazole과 질소와 황인 benzothiazole의 머무름거동은 정상 액체 크로마토그래피의 경우 시료 분자와 충진제의 흡착 표면과의 흡착력으로 설명할 수 있었고, 역상 액체 크로마토그래피의 경우는 시료와 정지상과의 소수성 상호작용 등으로 설명할 수 있었다.

• 한국연초학회지
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• 제30권1호
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• pp.33-38
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• 2008

This study was carried out to determine the analytical methods for heterocyclic amines(HAs) of the tobacco smoke by LC/MS/MS. HAs have been found in pyrolysate of protein and cooked food including protein, were known the Sugimura compound. HAs content of the smoke were known to exist very low ppb level. Especially, some of HAs are mutagenic and carcinogenic compounds. In according to IARC, the toxicity of N-heterocyclic amines classified IARC class 2A or 2B group. Precursors of these compounds are glutamic acid, protein and free amino acids including tryptophan, therefore, the precursors have been proved in cooked food continuously. This study was investigate multiple analysis methods for HAs and HAs contents of some commercial products. In this study, we used the linear type smoking machine for HAs analysis. At the ISO conditions, mainstream smoke was collected on cambridge filter pad, and then cambridge filter pad was extracted by 0.1% acetic acid. The extracted solution were passed cation exchange SPE cartridge to remove matrix, samples were analyzed using LC/MS/MS on MRM mode. From the result that optimized this methods, the correlation coefficient(R) of the individual compounds were good linearity over 0.999, recovery rate over 96% and the limit of detection were good values between 0.06 to 0.37 ng/mL, In addition, HAs content of some commercial products were in range of 0.02 to 43.8 ng/cig.

• Bulletin of the Korean Chemical Society
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• 제26권4호
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• pp.585-588
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• 2005

Bipyridine and its derivatives have been widely used as the ligands in transition metal complexes. The proton affinities of pyridine derivatives were calculated using an ab initio quantum mechanical method (B3LYP with various double zeta and triple zeta basis sets) in combination with the Poisson-Boltzmann continuum solvation model. Van der Waals radii of the atoms in the heterocyclic rings for the solvation energy calculation were set to values determined to reproduce the $pK_a$ values of guanine and oxoguanine derivatives and that of chlorine was optimized to reproduce the experimental values of relating compounds. The $pK_a$ values for the heterocyclic ring compounds were in agreement with the experimental values with a mean unsigned error of 0.45 $pK_a$ units.

• Food Science and Biotechnology
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• 제14권5호
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• pp.572-575
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• 2005

The effects of cooking method, cooking time and various food ingredients on the formation/ inhibition of heterocyclic aromatic amines (HAAs) in pork products were investigated. Three HAAs, 2-amino-3,8-dimethylimidazo [4,5-f] quinoxaline ($MeIQ_x$), 2-amino-3,4,8-trimethylimidazo [4,5-f] quinoxaline ($DiMeIQ_x$) and 2-amino-1-methyl-6-phenylimidazo [4,5-b] pyridine (PhIP) were measured in pork products using solid-phase extraction and HPLC. Pork patties were boiled, oven-broiled and pan-fried to internal temperatures of 71, 77 and $88^{\circ}C$. Generally, HAA concentrations increased with increasing internal temperature, and HAA formation was greatest with pan-fried. Selected food ingredients (vitamin E, sodium nitrite, sodium tripolyphosphate, sodium ascorbate, Nanking cherry tissue and cherry tissue extract) inhibited HAA formation in pork patties fried at $225^{\circ}C$ for 10 min/side, with the greater inhibition provided by cherry tissue and its methanolic extract.

• Bulletin of the Korean Chemical Society
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• 제35권2호
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• pp.610-616
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• 2014

The influence of solvent polarity on the absorption spectra of some synthesized azo dye with heterocyclic moieties and ${\beta}$-naphthol (1-3) have been investigated using a UV-Visible spectrophotometer. The spectral characteristics of the azo dyes (1-3) in different solvents at room temperature were analyzed. The solvatochromic empirical variables like ${\pi}^*$, ${\alpha}$, and ${\beta}$ have been used to discuss the solvatochromic behaviour of the dyes and to evaluate their contributions to the solute-solvent interactions. A multi-parameter regression model for quantitative assessment of the solute/solvent interaction and the absorption has been used to explain the solvent effect on azo dyes (1-3).

• Mycobiology
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• 제36권1호
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• pp.66-69
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• 2008

A simple, efficient and cost effective method is described for the synthesis of Biginelli type heterocyclic compounds of dihydropyrimidinones analogous. They were prepared from a reaction mixture consisting of substituted benzaldehydes, thiourea and ethylacetoacetate using ammonium dihydrogenphosphate as catalyst. The procedure for the preparation of the compounds is environmentally benign and safe which is advantageous in terms of experimentation, catalyst reusability, yields of the products, shorter reaction times and preclusion of toxic solvents. The four new synthesised compounds were tested for their antifungal activity. They have good antifungal activity comparing to the standard (Fluconazole).

• Bulletin of the Korean Chemical Society
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• 제31권4호
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• pp.859-862
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• 2010

The reactions of ketene dithioacetals with ethane-1,2-diamine, propane-1,3-diamine, 2-aminoethanol, 3-aminopropanol, and 2-aminoethanethiol in ordinary water in the absence of any acid/base catalyst afforded the heterocyclic ketene N,N-, N,O- and N,S-acetals in good yields.