• Journal of the Korean Ceramic Society
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• v.28 no.5
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• pp.383-389
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• 1991

The analysis of degradation phenomena of poled PZT ceramics was investigated relate to piezoelectric equivalent circuit elements. As a result, in the case of impressed mechanical shock on poled specimen of degradation phenomena was explained by domain rearrangement, and in the case of left in air, degradation phenomena was explained by space charge diffusion.

• Bulletin of the Korean Chemical Society
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• v.30 no.12
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• pp.3053-3056
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• 2009

The title compound, ${\alpha},{\alpha}$-dichloro-o-methylacetophenone, was prepared and its photochemical behavior was investigated. Addition of an extra chlorine at alpha position to the carbonyl showed many different features from photochemical reactivities of mono chloro analogue, 2,5-dimethylphenacyl chloride. In benzene, a rearrangement product with a formal 1,5-Cl shift and a reduction product were formed beside indanone. In methanol, solvolysis and cyclization of a common dienol intermediate occurred at comparable reaction rates.

• Journal of the Korean Chemical Society
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• v.53 no.3
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• pp.382-386
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• 2009

• Bulletin of the Korean Chemical Society
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• v.27 no.1
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• pp.35-36
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• 2006

• Archives of Pharmacal Research
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• v.29 no.6
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• pp.464-468
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• 2006

Novel phenyl branched apiosyl nucleosides were synthesized in this study. The introduction of phenyl group in the 4'-position was accomplished by a [3,3]-sigmatropic rearrangement. Apiosyl sugar moiety was constructed by sequential ozonolysis and reductions. The natural bases (cytosine and adenine) were efficiently coupled with an apiosyl sugar by classical glycosyl condensation procedure (persilyated base and TMSOTf). The antiviral activities of the synthesized compounds were evaluated against the HIV-1, HSV-1, HSV-2 and HCMV.

• Textile Coloration and Finishing
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• v.2 no.2
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• pp.14-19
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• 1990

The setting behavior of disulfide-enriched wool and disulfide-crosslinked silk obtained by treatment with a disulfide-containing crosslinking agent, bis $(\beta-isocyanatoethyl)$ dissulfide was compared with that of untreated wool and silk under the absence and the presence of a reducing agent. Rearrangment of secondary bonds facilitated by cleavage of crosslinks as well as rearrangement of crosslinks itself seems to play an important role in the set stability.

• Bulletin of the Korean Chemical Society
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• v.11 no.1
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• pp.58-59
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• 1990

A method is described for the selective functionalization of calix[4]arene at the para positions of the phenyl rings. The diametrically substituted calix[4]arene dimethyl ether 3, obtained from the treatment of calix[4]arene 2 with methyl iodide in the presence of $K_2CO_3$, is converted to the diacetyloxy calix[4]arene dimethyl ether 4. This compound undergoes Fries rearrangement to yield the diametrically p-diacetylcalix[4]arene dimethyl ether 5 in 68% yield.

• Bulletin of the Korean Chemical Society
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• v.21 no.9
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• pp.901-904
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• 2000

The mechanism for the photo-Fries rearrangement of phenyl acetate andbiphenylyl acetates were reinvestigat-ed in phenol (or phenol derivatives) containing media. The results showed that the phenol (or phenol deriva-tives) which is the most common by-product of Fries reaction reacts with acyl radical togive Fries-product. These phenol (or phenol derivatives) contributions to the Fries-products were suggested as the Trivial mecha-nism for the photo-Fries reaction.

• Bulletin of the Korean Chemical Society
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• v.16 no.11
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• pp.1122-1125
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• 1995

Three inherently chiral calix[4]arenes 3-5 were synthesized as racemate starting from the ethylation at 1.3-distal hydroxy groups of calix[4]arene 2 which has two phenyl groups at upper rim in AABB fashion, and then two remaining hydroxy groups were acetylated by treatment with acetyl chloride in the presence of NaH to produce calix[4]arene 4. Treatment of 4 with AlCl3 under Fries rearrangement conditions, only one acetyl group was rearranged to the para-position to afford calix[4]arene 5 with AABC substitution pattern at the upper rim of calix. The structure of chiral calix[4]arenes were confirmed based on NMR and massspectra.

• Proceedings of the PSK Conference
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• 2003.04a
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• pp.243.1-243.1
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• 2003

Extensive efforts in the search of therapeutically useful carbocyclic nucleosides have resulted in a wealth of their synthetic methodologies in racemic and optically active forms. The classical one-directional methods such as linear synthesis and convergent synthesis are the approaches most frequently seen in the literature for the preparation of carbocyclic nucleosides, and their advantages and limitations are well known. (omitted)