• 한국자기공명학회논문지
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• 제26권4호
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• pp.40-45
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• 2022

A small cage-like molecule (2) composed of three aminomethyl pyrroles and two hexa-substituted benzenes has been prepared by reduction of its iminopyrrole analogue (1) using NaBH₄. It was revealed by ¹H NMR spectroscopic analyses that cage molecule 2 strongly binds the fluoride anion in polar DMSO-d₆ relative to CDCl₃. Compared to that of compound 1, the lowered affinity of 2 for the fluoride anion is attributable to its increased electron density resulting from the production of thesecondary amine groups.

• Bulletin of the Korean Chemical Society
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• 제34권1호
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• pp.283-286
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• 2013

• Bulletin of the Korean Chemical Society
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• 제11권1호
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• pp.83-84
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• 1990

• Preventive Nutrition and Food Science
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• 제4권2호
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• pp.88-91
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• 1999

Aroma components of tea processed from Korean chicory roots were isolated and identified. The model system of amino-carbonyl reaction was carried out to study the formation mechanism of aroma compounds of chicory tea during manufacturing process. The concentration extracts from chicory tea and model system were analyzed and identified by gas chromatography(GC) and GC-mass spectrometry. Twenty-nine compounds, including pyrazines, furans, acids, alcohols, pyrroles and lactones were isolated and identified in chicory tea. The main compounds were pyrazines including methyl pyrazine, 2,5-dimethyl pyrazine, 2, 6-dimethyl pyrazine, 2-ethyl-6-methyl pyrazine, 2-ethyl-3-methyl pyrazine, thrimethyl pyrazine, 3-ethyl-2-5-dimenthyl pyrazine, 5-ethyl-2-3-dimenthyl pyrazine, and 2-acetyl-3-methy pyrazine and pyrroles including acethl pyrrole and formlyl pyrrole ; and furans including furfural , acetyl furan, 5-methyl furan, 5-methyl furfuralm, and furfuryl alcohol. These pyrazine compounds of a roasted and nutty aroma may be important contributors to the flavor of chicory tea. The aroma concentrate of model system also had a roasted and nutty aroma and the main compounds were methyl pyrazine, 2, 5-dimetyl pyrazine, 2, 6-dimethyl pyrazine and trimethyl pyrazine.

• Bulletin of the Korean Chemical Society
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• 제25권10호
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• pp.1545-1550
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• 2004

meso-Functionalized dipyrromethanes 6-10 were synthesized by acid-catalyzed addition of pyrrole to ${\alpha}$-position of 2-alkenyl pyrroles. The regiochemistry of the reaction can be explained by either the formation of more stable carbocation intermediate or ${\beta}$-addition of ${\alpha},{\beta}$-unsaturated carbonyl compounds. The starting 2-alkenyl pyrroles were synthesized by Aldol condensation of 2-formylpyrrole with active methylene compounds such as nitromethane, diethylmalonate and malononitrile. Attempted ‘2+2' condensation of meso-diethylmalonyldipyrromethane, meso-(p-tolyl)dipyrromethane and p-tolualdehyde afforded three different porphyrins 12, 13 and 14 in reasonable yields. On the other hand, meso-(nitromethyl)dipyrromethane with p-(tbutyl) benzaldehyde resulted in the formation of three different porphyrins such as 5,15-dicyano-10,20-diarylporphyrin (16), 5-cyano-15-formyl-10,20-diarylporphyrin (17) and 5,15-diformyl-10,20-diarylporphyrin (18) in low yields. Conversion of nitromethyl groups to nitrile and (or) formyl group was observed under the porphyrin forming conditions.

• 한국식품과학회지
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• 제20권2호
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• pp.157-163
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• 1988

Propylene glycol 용매계에서 0.5M DL-alanine(${\alpha}-amino-propionic acid$) 와 0.5M D-glucose 를 $100^{\circ}C,\;120^{\circ}C$ 및 $140^{\circ}C$에서 각각 20분, 2시간 반응시켜 생성되는 휘발성 화합물을 분석하고 반응온도와 시간이 갈색화반응 및 휘발성 화합물생성에 미치는 영향을 조사하였다. 갈색화반응 및 휘발성 화합물생성에 미치는 영향을 조사하였다. 갈색화반응은 반응온도와 시간이 증가함에 따라 급격히 증가 하였다. 휘발성 화합물은 7종의 alkylpyrazine, 4종의 pyrrole, 3종의 furan, 1종의 furanone 그리고 기타성분으로 2-hydroxy-3-methyl-2-cyclopenten-1-one을 포함하여 11종이 확인되었으며 pyrazine, pyrrole 및 furan화합물의 생성량은 반응온도가 높아지고 반응시간이 길어짐에 따라 급격히 증가하였다. 또한 alanine과 glucose의 마이야르 반응에 의해 생성되는 구수한 카라멜냄새 및 설탕 탄냄새(burnt sugar-like)는 주로 2-hydroxy-3-methyl-2-cyclopenten-1-one, 2, 5-dimethyl-4-hydroxy-3(2H)-furanone과 같은 함 산소화합물과 pyrazine, pyrrole과 같은 함 질소화합물에 의해 생성되는 것으로 추정되었다.

• 약학회지
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• 제43권6호
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• pp.776-781
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• 1999

Dockings of 4,5-diarylpyrroles into cyclooxygenase-1 and cyclooxygenase-2 were carried out by GOLD program. The sulfonyl groups bonded to 5-phenyl ring of 4,5-diarylpyrroles are directed to Arg513 of COX-2 and Tyr385 of COX-2 docking modes of pyrroles are different from COX-1. Tyr385 and Arg120 of COX-1 and COX-2 have been recognized as important residues. Val523 of COX-2 may be also important. A new COX-2 selective inhibitors could be designed from the docking study.

• Bulletin of the Korean Chemical Society
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• 제31권3호
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• pp.630-634
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• 2010

The synthesis and ion binding properties of calix[4]pyrrole bearing pyrene moieties appended to one side of the calix[4]pyrrole are reported. The key feature is the presence of flexible fluorescence arms attached to the calix[4]pyrrole ring in a cis-fashion. The preliminary solution phase anion and cation binding studies revealed that the systems can be in fact as viable sensors for anionic guest.

• Bulletin of the Korean Chemical Society
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• 제26권8호
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• pp.1190-1196
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• 2005

Halopyrroles, N-substituted 2-halopyrroles were prepared by halogenation of N-substituted pyrroles with NBS, NCS, or surfuryl chloride. N-Substituted 3-halopyrroles were synthesized by acid-catalyzed thermal and photochemical isomerization reactions of N-substituted 2-halopyrroles. Both the thermal and photochemical reactions were acid-catalyzed. For the acid-catalyzed isomerization, a mechanism of [1,3] bromine shift followed by deprotonation is operated. For the acid-catalyzed photoisomerization, an excited triplet state of 2-protonated N-benzyl-2-halopyrrole produces an intermediate N-substituted pyrrole complex with halonium ion which is equilibrated with N-substituted pyrrole plus halonium ion, and then the halonium ion newly adds to 3-position of N-substituted pyrrole followed by deprotonation to afford N-benzyl-3-halopyrrole.

• Bulletin of the Korean Chemical Society
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• 제31권4호
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• pp.815-818
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• 2010

Free base meso-tetraarylporphyrins ($H_2T(X)PP$) react with tellurium(IV) chloride ($TeCl_4$) in mild conditions for formation sandwich intermediate sitting-atop (i-SAT) complexes, [$TeCl_4(H_2T(X)PP)_2$]. $^1H$ NMR, $^{13}C$ NMR, UV-vis, FT-IR and elemental analysis were used for characterization of the products. In the proposed structure of the i-SAT complexes, four pyrroles of each porphyrin ring are tilted alternatively up and down and this appropriates suitable orientation of lone pairs of two pyrrolenine nitrogens for electron donation to a tellurium center. $^1H$ NMR and FT-IR results showed that in the produced complex, hydrogen atoms of porphyrin macrocycles remained on the pyrrole nitrogens.