• Carbon letters
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• 제19권
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• pp.104-106
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• 2016

• Nuclear Medicine and Molecular Imaging
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• 제43권1호
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• pp.1-9
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• 2009

As many new drug substances contained various aromatic rings and fluorine attached to an electron rich aromatic ring or on the meta-position, a strategy towards improvement in aromatic fluorination of these compounds is highly desirable. The introduction of fluorine-18 onto aromatic rings showed in the limited condition containing electron withdrawing group (EWG) on the para- or ortho-position to get reasonable radiochemical yield so far. No-carrier added (NCA) [$^{18}F$]fluoroarene syntheses by iodonium salts recently reported that has the potential to greatly increase the yield in systems or positions that normally not reactive enough to give sufficient yields in simple model reaction. This review describes the methodological approach towards effective aromatic fluorination by diaryliodonium salts and future prospects in an application of novel PET radiotracer.

• 한국작물학회지
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• 제42권6호
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• pp.748-751
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• 1997

본 연구는 한국산 마의 괴근 형태로 분류되는 장마와 단마를 개화기에 꽃의 방향 성분과 정유수율을 비교조사하여 향료로서의 기능성을 검토하기 위하여 실험을 수행하였던 바 얻어진 결과를 요약하면 아래와 같다. 1. 마꽃의 방향 성분은 총 26종이 확인되었으며 지방족 알콜류가 다량분포하여 향료 첨가물이나 향수의 기본재료로의 가능성이 있는 것으로 나타났다. 2. 단마는 장마보다 1,2-butyleneglycol은 11배, phenylalcohol은 12배, caproic acid는 28배, cis-3-methylsalicylate는 8배, cinnamic alcohol은 25배, $\alpha$-hexyl cinnamic acid는 13배, laulic acid는 6배 높은 경향을 보였다. 3. 마꽃 방향 성분의 수율은 0.7%로서 그 이용 가능성이 크며 단마가 0.983%, 장마가 0.417%로 단마가 약 2.4배 수율이 높았다. 4. 마꽃의 방향 성분 조성과 정유성분 수율을 감안할 때 마의 부산물인 마꽃을 향료로서의 이용 가능성이 있다고 판단되었다.

• Journal of Photoscience
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• 제9권3호
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• pp.71-74
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• 2002

The fluorescent conjugated aromatic imine derivatives are systematically designed and synthesized as the high yield through the simple one-pot condensation reaction. The emission of the synthesized conjugated aromatic imine derivatives can be tuned efficiently in the range of about 100 nm by the change of electron donating groups constituting parent molecule, which shows the considerable quantum yields from 0.38 to 0.56.

• 한국자원식물학회지
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• 제11권3호
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• pp.279-282
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• 1998

This expriment was carried out to get basic information on composition and yield of aromatic constituents in leaves of four medicinal plants, Angelica tenuissima, Chrysanthemum zawadskii. ssp. latilobum, Artemisia iwayomogi and Artemisia capillaris. Volatile aromatic constituents, 28 compounds in Angelica tenuissima were identified and 19 compounds were indentified in Chrysanthemum zawadskii ssp. latilobum. Volatile aromatic constituents, 23 compounds in Artemisia iwayomogi and Artemisia capillaris were identified. Major volatile aromatic consitiuents analyzed by GC/MS in four plants were $\alpha$-pinene, camphene, sabinene, cis-2-hexanol, and camphor etc. Content of essential oils in Angelica tenuissima, Chrysanthemum zawadskii ssp. latilobum, Artemisia iwayomogi and Artemisia capillaris were 0.014, 0.275, 0.785, and 0.452%, respectively. As a result, it was suggested that a medicinal plant, Artemisia iwayomogi, was worthy of using as a useful material of perfume.

• 대한화학회지
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• 제30권1호
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• pp.105-108
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• 1986

초음파(50KHz)가 상온 상압하에서 히드라진 철 활성탄을 이용한 방향족 니트로기를 방향족 아미노기로의 환원반응을 크게 가속시켜 3시간만에 100% 전환율을 얻을 수 있었다. 활성탄은 탈색이나 반응성이 큰 물질의 분말을 섞는데 사용되어 왔으나 히드라진 철을 이용한 방향족 니트로기의 환원반응에서는 활성탄 없이는 반응이 전혀 일어나지 않으며 활성탄의 증가에 따라 환원율이 높아지는 결과를 얻었다.

• 한국연초학회지
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• 제3권1호
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• pp.49-57
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• 1981

To obtain genetic information for breeding aromatic tobacco, broad sense heritabilities, phenotypic, and genotypic correlations were obtained for the following characters : days to frowert, plant height, number of leaves, leaf shape and nicotine. Six pure line varieties and the first and second generations of 5 crosses among them were employed in this study. The heritabilities for number of leaves and nicotine were very high in pure line varieties. However, the heritabilities for days to flower and yield were low in six varieties as well as in F2. Genotypic correlations had higher values than phenotypic did. Heritabilities calculated from segregating generations were lower than those from pure varieties, regardless of crosses involved. Positive phenotypic correlations between yield and plant height were observed in all crosses. Same phenomenon was observed with correlations between days to flower and number of leaves. The genotypic and phenotypic variances and covariances entering into the computation of correlations were used to construct the seletion indices for yield. The use and limitation of selection index was also discussed.

• Bulletin of the Korean Chemical Society
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• 제26권4호
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• pp.599-602
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• 2005

The aromatic fluorination method involving the acid-catalyzed decomposition of a triazene in an ionic liquid is a very convenient and efficient way to prepare a variety of aromatic fluorides in a lab-scale. It should be particularly useful for the preparation aryl fluorides substituted with electron withdrawing substituents. Fluorination of triazene 1 (1.0 mmol) and p-toluenesulfonic acid (1.2 mmol) in an ionic liquid, 1-butyl-3-methylimidazolium tetrafluoroborate ([bmim][$BF_4$], 2.5 mL) proceeds very smoothly at 80 ${^{\circ}C}$ with or without an external source of fluoride, providing 73% yield in 30 min. Unlike diazonium salts, triazene precursors are stable enough to be stored for a long period of time without a noticeable decomposition.

• Bulletin of the Korean Chemical Society
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• 제16권7호
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• pp.609-613
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• 1995

The reaction of chloro(methylthio and arylthio)methanephosphonate (1) and Pummerer-type reaction of sulfinylmethanephosphonate (2) with nucleophiles such as aromatic compounds and thiols were examined. The direct chlorination of (methylthio and arylthio)methanephosphonate with N-chlorosuccinimide (NCS) led to the formation of monochlorinated phosphonates (1) in good yield. The reaction of 1 with aromatic compounds and thiols in the presence of stannic chloride afforded a variety of aryl(methylthio)methanephosphonates (3) and thioacetals of formylphosphonates (4), respectively. Phosphonates 3 and 4 were also obtained from the reaction of Pummerer intermediate, generated from sulfinylmethanephosphonate (2), with aromatic compounds and thiols, respectively. A versatile reaction conditions to generate Pummerer intermediate were examined. The best condition was the combination of trifluoroacetic anhydride with stannic chloride. All reactions may involve an initial formation of α-phosphoryl thiocarbocation and a subsequent nucleophilic attack of aromatic compounds and thiols.

• Bulletin of the Korean Chemical Society
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• 제11권3호
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• pp.224-227
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• 1990

The excitation mechanism of polycyclic aromatic amines (amino-PAHs) and polycyclic aromatic hydrocarbons(PAHs) for the chemiluminescence arising from the reaction between oxalate ester, bis(2,4,6-trichlorophenyl)oxalate (TCPO) or bis(2,4-dinitrophenyl)oxalate (DNPO) and hydrogen peroxide has been studied in terms of the excitation efficiencies to singlet excitation energies and the oxidative half-wave potentials. As a results of the study, the excitations of both amino-PAHs and PAHs appear to involve the charge transfer type of energy transfer. However the chemiluminescence efficiency corrected for fluorescence quantum yield of the amino-PAHs are varied more sensitively to the oxidative half-wave potential than that of PAHs possibly due to the large difference in solvation energy between the compounds and their ions.