• Bulletin of the Korean Chemical Society
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• v.8 no.3
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• pp.162-165
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• 1987

The reduction rate of borohydride exchange resin (BER) was greatly enhanced in the presence of lithium salts. Thus 2-heptanone was reduced completely with BER-LiCl in 1 h at room temperature. However, no reduction was observed with BER alone under the same conditions. With this system, organic compounds containing various fuctional groups were examined in ethanol at room temperature. This study revealed that BER-LiCl system exhibits an excellent chemoselectivity for carbonyl group in the presence of other functional groups. Keto esters and epoxy ketones were reduced with BER-LiCl to give the corresponding hydroxy esters and epoxy alcohols with excellent yields. Selective reductions of carbonyl groups were also possible in the presence of other organic compounds containing functional groups such as 1-idooctane, 1-bromooctane, caproamide, hexanenitrile, nitrobenzene, n-butyl disulfide, dimethyl sulfoxide and 1-dodecene.

• Journal of Integrative Natural Science
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• v.1 no.3
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• pp.192-194
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• 2008

A series of non-free hydride reducing systems containing boron or aluminum atom, which possess no metal-hydride bond but an available hydrogen at a branched ${\beta}$-position, has been applied to the selective reduction (chemo--, regio-, and stereoselective reduction) of organic compounds. The systems, comprised of diisopinocampheylborane and diisobutylalane derivatives, exhibited almost perfect selectivities in the reduction of aldehydes and ketones. The characteristics features of this systems leading to a perfect transformation have been depicted in this report, especially in the 1) Reduction of ${\alpha}$,${\beta}$-Unsaturated Carbonyl Compounds to Allylic Alcohols via 1,2-Reduction, 2) Chemoselective Reduction between Structurally Different Carbonyl Compounds, and 3) Stereoselective Reduction of Cyclic Ketones.

• YAKHAK HOEJI
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• v.17 no.4
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• pp.223-234
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• 1973

Sixteen compounds of N-aroyl-N'-(4'-alkoxyphenyl) thiourea derivative, twenty one compounds of N-aeryl-N'(3'-hydroxy-4'-alkoxycar-bonylphenyl) thiourea derivative, three compounds of N-aeroyl-N'-.alpha.-naphthyiourea derivative and three compounds of N-cyanoacetyl-N'-aroyl thiosemicarbazide derivative were syntrhesized as potential antitubercular agent and were subjected to screening test for antitubercular activity against Mycobacterium turberculosis H/sub 37/Rv by tube dilution method in vitro. Of the fourty three eompounds, N-p-cyanobenzoyl-N'-(4'-iso-butoxyphenyl) thiourea, N-p-cyanobenzoyl-N'-(4-n-amoxyphenyl)thiourea, N-furoyl-N'-(3'-hydroxy-4'-ethoxycarbonylphenyl)thiourea, N-p-cyanobenzoyl-N'-(3'-hydroxy-4'-n-butoxycarbonylphenyl)thiourea, N-p-cyanobenzoyl-N'-(3'-hydroxy-4'-n-amoxycarbonylphenyl)thiourea, and N-5-nitrofuroyl-N'(3'-hydroxy-4"-n-amoxycarbonylphrnyl)thiourea showed the growth inhibition of M. tuberculosis H/sub 37/Rv at the coccentraction og 10.mu.g/ml, respectively.

• Proceedings of the Korea Air Pollution Research Association Conference
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• 2007.10a
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• pp.123-125
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• 2007

• Proceedings of the Korea Air Pollution Research Association Conference
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• 2010.04a
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• pp.438-440
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• 2010

• Bulletin of the Korean Chemical Society
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• v.25 no.1
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• pp.42-44
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• 2004

Valerophenones containing a substituent at alpha position to the carbonyl group show the remarkable substituent effects on their photochemical reactions. ${\alpha}$-Bromovalerophenone gives only the C-Br bond cleavage products, but the ${\alpha}$-chlorovalerophenone follows the classical Norrish/Yang reaction pathway predominantly.

• Bulletin of the Korean Chemical Society
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• v.20 no.12
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• pp.1437-1440
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• 1999

Ozonolysis reactions of indene 5 in the presence of carbonyl compounds 6 provided the corresponding indenemonoozonide 9 and cross-ozonides 10a-c and 11a-c. Further reactions of ozonides 10 and 11 with the independently prepared carbonyl oxide 13 gave diozonides of structure 14a-c and 15a-c.

• Korean Journal of Food Science and Technology
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• v.7 no.1
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• pp.15-21
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• 1975

Soong-Neung is a Korean traditional beverage served after meals and is made from cooked and roasted rice produced on the bottom of the container during the rice cooking process. The volatiles from the extract of cooked and roasted rice were separated into pyrazine and carbonyl fractions and qualitatively investigated. The pyrazine fraction was characterized by gas chromatography and combined gas chromatography-mass spectrometry and five pyrazines were positively identified. Pyrazine compounds identified are 2-methylpyrazine, 2,3-dimethylpyrazine, 2,5-dimethylpyrazine, 2-ethyl-5-methylpyrazine and 2-ethyl-3-methylpyrazine. Carbonyls were converted to their 2,4-dinitrophenylhydrazones and identified by gas chromatography, combined gas chromatography-mass spectrometry and thin layer chromatography. Acetaldehyde, propionaldehyde, iso-butyraldehyde and iso-valeraldehyde were positively identified in the carbonyl compounds. The aroma of the fractions indentified as 2,3-dimethylpyrazine and 2,5-dimethylpyrazine had a nut-like or roasted cereal-like flavor, which is one of the characteristic flavors of Soong-Neung.

• Korean Journal of Food Science and Technology
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• v.5 no.1
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• pp.65-69
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• 1973

Effect of various dosages of gamma ray ranging from 0 to 16 krad on wound periderm formation was investigated with aging potato tuber slices $(1cm{\times}2mm)$ under aseptic condition. Cell division was gradually inhibited with increasing dosage, and completely prevented with 16 krad treatment. Solanine content was not significantly different due to dosages. Gas chromatographic separation of 2,4-dinitrophenylhydrazone precipitate from radiation-induced carbonyl compounds in potato tubers showed that formaldehyde and acetone tended to be increased only with high dosages.

• Proceedings of the Korea Technical Association of the Pulp and Paper Industry Conference
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• 2006.06a
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• pp.173-176
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• 2006

Pyrolysis-gas chromatography (Py-GC) in the presence of organic alkali of tetrabutylammonium hydroxide (TBAH) was applied to characterize the polyphenol fragments with a carbonyl group causing different magnitude of photo-yellowing in chemithermomechanical pulp (CTMP) papers. Two different origin of CTMP papers prepared from different individuals of Eucalyptus globulus trees showing high and low yellowing after photo-irradiation was compared before photo-irradiation. As a result, 7 peaks assigned to a series of phenol compounds with a carbonyl group, derived mainly from lignin, gave significant amount of phenol compounds with a carbonyl group for the paper sample of latent high yellowing, i.e., butoxy-and syringaldehyde, butoxy-and syringylacetone, butoxy-acetoguaiacone, butoxy-acetosyringone, butoxy-acetoethylsyringone, 3-methoxy-4-butoxy butyl ester, and 3,5-dimethoxy-4-butoxy butyl ester, using Py-GC/mass spectrometry (MS). The Py-GC method combined with TBAH successfully characterized polyphenol fragments with a carbonyl group causing differ high photo-yellowing in CTMP papers using a microgram order of samples.