• 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.

• Journal of Pharmaceutical Investigation
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• v.22 no.3
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• pp.49-63
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• 1992

Two different types of chemical manipulations of dobutamine were investigated in order to develop novel, improved cardiotonic drugs. Three new analogues of carbostyril, in which the m-hydroxy group of dobutamine was isosterically modified with an amide type carbostyril system, were synthesized from, ${\rho}-methoxyphenethylamine$ via multi-steps. Two analogues of (2'-aminoethyl)-1-hydroxy-2-pyridone system which has isosteric structural similarity with dopamine without having the COMT vulnerable m-hydroxy group were synthesized via 12 synthetic steps. Their biological stabilities in various media and inotropic activities were evaluated.

• Bulletin of the Korean Chemical Society
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• v.29 no.11
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• pp.2277-2280
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• 2008

• Bulletin of the Korean Chemical Society
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• v.20 no.7
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• pp.857-859
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• 1999

• Bulletin of the Korean Chemical Society
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• v.35 no.10
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• pp.3021-3024
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• 2014

The potential energy surface (PES) for the dissociation of the 2-hydroxypyridine (2-HP) radical cation was determined from G3//B3LYP calculations, including the loss of CO, HCN, and HNC. The formation of the 1H-pyrrole radical cation by decarbonylation through a more stable tautomer, the 2-pyridone (2-PY) radical cation, was the most favorable dissociation pathway. Kinetic analysis by the Rice-Ramsperger-Kassel-Marcus model calculations was carried out based on the obtained PES. It is proposed that the dissociation occurs after a rapid tautomerization to 2-$PY^{{\cdot}+}$, and that most of the ions generated by ionization of 2-HP have the structure of 2-$PY^{{\cdot}+}$ at equilibrium above the tautomerization barrier.