• 한국응용과학기술학회지
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• 제14권3호
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• pp.39-46
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• 1997

Ultraviolet spectrophotometric investigation has been carried out on the rate constants for 1,3-dipolar cycloaddition of 4-substituted-3-phenyloxadiazole derivatives with dipolarophiles such as phenyl acetylene, propiolic acid methyl ester and dimethylacetylene dicarboxylate. From there, the rate constants for 1,3-dipolar cycloaddition were determined at 80, 100 and $120^{\circ}C$, and the reaction rates were increased with increasing temperature. From these rate constants, the values of the thermodynamic activation parameters were obtained. Some thermodynamic activation parameters such as $E_{\alpha}$, ${\Delta}H^{\ast}$, ${\Delta}S^{\ast}$ and ${\Delta}G^{\ast}$ from Arrhenius equation were also calculated for the electrophilic 1,3-dipolar cycloaddition of 3-phenyloxadiazole derivatives with dipolarophiles. In order to the proposal the mechanism and reactivity of 1,3-dipolar cycloaddition reaction, the effect of substituents having various kinds of electron withdrawing or releasing groups were examinated. Considering the effect of substituents, an electron withdrawing group attached at the 4-carbon position in 3-phenyloxadiazole derivatives decreases the reaction rate because of the lack of electron density in 3-phenyloxadiazole ring.

• Bulletin of the Korean Chemical Society
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• 제23권3호
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• pp.511-514
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• 2002

• 대한화학회지
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• 제52권3호
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• pp.249-256
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• 2008

3-Acetyl/Formyl 4-hydroxy-2H(1)-benzopyran-2-one를 malonitrile와 ethyl cyanoacetate로 처리하여 각각 1,1-dicyano-2-[4/-hydroxy-2/H(1)-benzopyran-2/-one-3/-yl] ethene/propene 2a-h와 ethyl-2-cyano-3-[4/-hydroxy-2/H (1)-benzopyran-2/-one-3/-yl] propenoate/butenoate 3a-h를 얻었다. NaN3와 2a-h의 1.3 dipolar 반응에서 4a-h인 tetrazole유도체를 얻었다. 3a-h는 PPA를 이용한 고리화 반응으로 3-cyano-2H,5H-pyrano [3, 2-c] benzopyran-2,5-diones 5a-h를 얻었다. 5a-h는 NaN3와1.3 dipolar 반응으로 -(1/H-tetrazol-5/-yl)-2H,5H-pyrano[3, 2-c] benzopyran-2,5-diones 6a-h얻었다. 화합물의 구조는 스펙트럼과 자료 분석을 기초로 입증했다.모든 화합물은 항균 활성을 검사하였고 의미있는 항균성을 가짐을 밝혔다. 2h화합물과 4h 화합물은 50 킽/mL에서 활성을 보였다

• Bulletin of the Korean Chemical Society
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• 제27권7호
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• pp.1083-1085
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• 2006

• 약학회지
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• 제44권4호
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• pp.325-333
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• 2000

The 1,3-dipolar cycloaddition reaction of the quinoxaline 4-oxides 2 with 2-chloroacrylonitrile gave the 2,3-dihydro-1H-1,2-diazepino[3,4-b]quinoxalines 3, which were converted into the 2,3,4,6-tetrahydro-1H-1,2-diazepino[3,4-b]quinoxalines 5-7. The reaction of compounds 3 with selenium dioxide in acetic acid/water resulted in ring transformation to give the 1,4-dihydro-4-oxopyridazino[3,4-b]quinoxalines 8.

• 대한화학회지
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• 제59권3호
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• pp.205-208
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• 2015

• 대한약학회:학술대회논문집
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• 대한약학회 2002년도 Proceedings of the Convention of the Pharmaceutical Society of Korea Vol.2
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• pp.362.2-362.2
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• 2002

Antofine belongs to the Phenathroindolizidine group of alkaloids. This natural products exhibit interesting biological properties such as antitumour activity. and anti-inflammentory. Wittig reaction of phenathrenealdehyde with the phosponium salt provided the phenathreneazidealkene in good yield. Intramolecular 1.3-dipolar cycloaddition of the resulting azidealkent in refluxing benzene proceeded the imine. It was reduced with cyanoborohydride of Noyori's Asymmetric Hydrogenation. (omitted)

• Bulletin of the Korean Chemical Society
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• 제8권4호
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• pp.233-235
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• 1987

The kinetics of the 1,3-dipolar cycloaddition of p-substituted 3-phenylsydnones 1a-d with DMAD have been investigated. The reaction rates over a temperature range $100-140^{\circ}C$ were measured by UV spectrometry. The reactions found to be second-order overall, insensitive to the dielectric constants of the solvents, and characterized by a large entropy of activation. These findings are consistent with the rate-determining step involving the formation of cyclic transition state 1 and the reaction proposed to be concerted.

• Bulletin of the Korean Chemical Society
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• 제23권3호
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• pp.437-440
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• 2002

A variety of 1,2,3-triazole derivatives bearing acyclic sugar moieties of DHPG and iso-NDG were synthesised by Diels-Alder reaction. None of the new compounds display any interesting biological activity.

• Bulletin of the Korean Chemical Society
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• 제19권7호
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• pp.725-726
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• 1998