• Proceedings of the Korean Vacuum Society Conference
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• 2013.08a
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• pp.137-137
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• 2013

The most stable adsorption structures and their corresponding energies of 4-pyridone, 4-hydroxypyridine, 2-pyridone and 2-hydroxypyridine have been investigated by Density Functional Theory (DFT) calculation method and high-resolution photoemission spectroscopy (HRPES). We confirmed that between the two reaction centers of 4- and 2-pyridone, only O atom of carbonyl functional group can act as a Lewis base and thus, O dative bonding structure is the most stable. On the other hand, we clarified that both the two reaction centers (the cyclic N atom and the O atom of hydroxyl functional group) of 4- and 2-hydroxypyridine (tautomers of 4- and 2-pyridone) can successfully function as a Lewis base. Through the interpretation of the N 1s and O 1s core level spectra obtained using HRPES, we could confirm the electronic structures and bonding configurations of these molecules with a coverage dependence on the Ge(100) surface.

• YAKHAK HOEJI
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• v.37 no.1
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• pp.36-40
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• 1993

The 4-(2'-(N-(l-methyl-3'-carbamylphenyl)-n-propyl))aminoethyl)-l- hydroxy-2-pyridone which has isoelectronic and isosteric structural similarity with dobutamine without having the Catechol-O- Methyltransferase(COMT) vulnerable m-hydroxy group was synthesized via 12 synthetic steps.

• Bulletin of the Korean Chemical Society
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• v.35 no.2
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• pp.581-586
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• 2014

The most stable adsorption structures and their corresponding energies of 4-pyridone, 4-hydroxypyridine, 2-pyridone and 2-hydroxypyridine have been investigated by Density Functional Theory (DFT) calculation and high-resolution photoemission spectroscopy (HRPES). We confirmed that between the two reaction centers of 4- and 2-pyridone, only O atom of carbonyl functional group can act as a Lewis base while both the two reaction centers of 4- and 2-hydroxypyridine (tautomers of 4- and 2-pyridone) can successfully function as a Lewis base. On the other hand, owing to their molecular structures, there is a remarkable difference between the adsorption structures of 4- and 2-hydroxypyridine. Through the analysis of the N 1s and O 1s core level spectra obtained using HRPES, we also could corroborate that two different adducts coexist on the surface at room temperature due to their activation energy investigating the coverage dependent variation of bonding configurations when these molecules are adsorbed on the Ge(100) surface.

• Bulletin of the Korean Chemical Society
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• v.35 no.8
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• pp.2547-2550
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• 2014

• Korean Journal of Pharmacognosy
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• v.48 no.4
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• pp.268-272
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• 2017

Three tricyclic pyridone alkaloids, (-)-4,6'-anhydrooxysporidinone (1), (-)-6-deoxyoxysporidinoCne (2), and (-)-sambutoxin (3) were isolated from cultures of Fusarium lateritium SSF2 derived from the fruits of Cornus officinalis. Chemical structures of the isolated compounds were determined by spectroscopic method and comparisons with reported data values. The compounds 1-3 were isolated for the first time from this fungal strain.

• Korean Journal of Food Science and Technology
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• v.34 no.1
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• pp.8-12
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• 2002

In order to artificially increase the contents of essential oils from 4 different trees by inducing with elicitors, 5 kinds of chemical elicitors and 4 kinds of biotic elicitors were selected. Before treatment, the contents of essential oils from Japanese Cypress (Chamaecyparis obtusa), Sawara cypress (Chamaecyparis pisifera), Japanese Red Pine (Pinus densiflora), and Korean Pine (Pinus koraiensis) were 2.0, 1.6, 0.4, and 0.7 percent, respectively, and the maximum content of essential oils from all species were reached in July. By most of elicitors, the essential oil content was generally increased after 6 months later, but some of elicitors did not affect the content of essential oil. Finally, the appropriate inducers for artificially increasing the essential oil were respectively selected depending on each species; Schizophyllum commune Fries for Japanese Red Pine and Japanese Cypress, hydrogen peroxide for Korean Pine, and ${\beta}-pyridone$ for Sawara cypress. Especially, hydrogen peroxide and ${\beta}-pyridone$ could be wide spread inducer for all 4 species.

• Bulletin of the Korean Chemical Society
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• v.22 no.2
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• pp.234-236
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• 2001

• Journal of Applied Biological Chemistry
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• v.59 no.2
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• pp.165-169
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• 2016

The quantitative analytical method for the bioactive substance, 3-cyano-4-methoxy-N-methyl-2-pyridone (ricinine) and an index compound, ricinoleic acid in castor plant (Ricinus communis) extract or oil was developed. For the determination of a pyridone alkaloid compound, ricinine, successive cartridge cleanup method combined with ultra-performance liquid chromatography was set up with $ENVI-Carb^{TM}$ (0.5 g) and $C_{18}$ SPE cartridges. Accuracy and precision were evaluated through fortification studies of one biopesticide (PE) at 10 and $100mg\;kg^{-1}$. Mean recoveries of ricinine were 98.7 and 96.0 % associated with less than 10 % RSD, respectively. For the determination of ricinoleic acid in castor extract and oil, saponification and methylation were optimized using gas chromatography-time of flight mass spectrometry. Recovery was more than 84.8 % associated with 6.2 % RSD after derivatization procedure. Both methodologies developed were applied to analyze real samples including three castor oil products and six commercially available biopesticides containing R. communis, collected at Korean market. The contents of ricinine and ricinoleic acid in most commercial biopesticides were less than the oil or extract contents indicated by label.

• Korean Chemical Engineering Research
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• v.49 no.4
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• pp.443-448
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• 2011

The propellant has a short shelf-life because of nitrogen oxides that were released from nitrocellulose decomposition. As-received and surface-modified ACFs were applied to remove the nitrogen oxides with intend to extend the shelf-life of propellant. The specific surface area of modified ACFs was slightly decreased but nitrogen function groups such as pyridine, pyridone and pyrrol were created on the surface of ACFs. As a result, the NO removal capacity of the surface-modified ACF by propellant waste increased about twice than that of the as-received ACF. The shelf-life of propellant was extended about 1.25 times by accompanying surface-modified ACF.

• Textile Coloration and Finishing
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• v.17 no.6 s.85
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• pp.1-10
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• 2005

Disperse dyes derived from heterocyclic compounds such as phenylindole, pyridone, diaminopyridine, and carbazole have been known to exhibit high light fastness and bathochromic shift compared to the coursponding aminoazobenzene. The synthetic method to obtain diaminopyridine derivatives, which can be used as coupling components, was chlorination of pyridone with phosphorous oxychloride, followed by substitution with various primary amines. Four azo disperse dyes were synthesized by coupling four diaminopyridines with 2-cyano-4-nitroaniline as a diazo component. Structures of these dyes were confirmed by $^1H$ NMR spectroscopy. The wavelengths of maximum absorption of the synthesized disperse dyes were in the range of $517\~528nm$, and molar extinction coefficients were $45,700\~50,100$. The dyeability of four disperse dyes toward PET fiber was generally good. Wash and rubbing fastnesses were excellent, while light and dry heat fastness were good.