• Carbon letters
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• v.19
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• pp.104-106
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• 2016

• Nuclear Medicine and Molecular Imaging
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• v.43 no.1
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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.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.42 no.6
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• pp.748-751
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• 1997

The study was carried out to identify compositions and recovery yield of aromatic compounds of flower in Chinese yam (Dioscorea batatas Decne). Total 26 volatile aromatic compounds were identified and peak area percentage of aliphatic alcohol in Dan-ma was higher than in Jang-ma. Major volatile aromatic compounds analyzed by GC/MS were 1,2-butyleneglycol, phenylalcohol, caproic acid, cinnamic alcohol, and palmitic acid. Recovery yield of essential oils of Dan-ma was higher than in Jang-ma as 0.983％. As a result, it was concluded that Chinese yam was worthy of cultivating as perfume and medicinal crops.

• Journal of Photoscience
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• v.9 no.3
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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.

• Korean Journal of Plant Resources
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• v.11 no.3
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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.

• Journal of the Korean Chemical Society
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• v.30 no.1
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• pp.105-108
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• 1986

Ultrasound(50KHz) accelerated the reduction reaction of aromatic nitro group to aromatic amino group in high yield with mild condition using iron, hydrazine hydrate and activated carbon under room temperature and atmospheric pressure. The activated carbon has been used as a mixing material to highly active metals. However, aromatic nitro group does not reduce at all only with iron-hydrazine witliout adding activated carbon even under ultrasonic irradiation. We also discovered that the conversion yield from nitro group to amino group is directly proportional to the amount of activated carbon.

• Journal of the Korean Society of Tobacco Science
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• v.3 no.1
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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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• v.26 no.4
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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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• v.16 no.7
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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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• v.11 no.3
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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.