• Archives of Pharmacal Research
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• 제9권1호
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• pp.19-20
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• 1986

Reaction of dine alcohol 5 and maleic anhydride in benzene at either room temperature or reflux proceeds probably through a intermolecular Diels-Alder cycloaddition followed by lactone formation to give adduct 6.

• Bulletin of the Korean Chemical Society
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• 제23권7호
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• pp.1021-1022
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• 2002

• Bulletin of the Korean Chemical Society
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• 제23권6호
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• pp.829-837
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• 2002

Recently it was reported that cycloaddition of 6,6-disubstituted cyclohexa-2,4-dienone, 1 with cyclopentadiene gave solely the adduct of type 1.while its reaction with 1,3-cyclohexadiene gave both Ⅱ and Ⅲ. Semiempirical MO calculations were done to elucidate the origin of the selectivity difference between the two dienes. Cycloaddition of 1 with cyclopentadiene is controlled thermodynamically to give only 1-diene adduct by ΔGvalues of 10.6-20.3 kcal/mol, while its reaction with 1,3-cyclohexadiene does not show 1-diene/1-dienophile selectivity due to similar stabilities of the two adducts. Thermodynamic parameters also show that 두애 adducts are more fabourably fromed in the cycloadditions of 1 with both cyclopentadiene and 1,3-cyclohexadiene, which coincides with experimental observations. Cope rearrangements of endo adducts are another avenue to convert between 1-diene and 1-dienophile.

• Applied Biological Chemistry
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• 제35권5호
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• pp.395-398
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• 1992

Griseofulvin의 구조활성상관연구에서 6'-methyl기와 4'-oxo기가 생물활성에 있어서 중요한 인자라는 것이 예견되어, 6'-methyl기(基)를 phenyl기(基)로 치환한 6'-phenylgriseofulvin을 diels-alder부가환화로 합성하고 Botrytis allii 및 B. cinerea에 대한 항균활성을 paper disc 법으로 연구하였다. 6'-Phenylgriseofulvin은 $25\;{\mu}g/disc$에서 높은 항균활성을 나타냈다.

• Bulletin of the Korean Chemical Society
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• 제4권5호
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• pp.197-200
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• 1983

The Diels-Alder cycloaddition reactions between dienes and allenic ketones were studied theoretically using CNDO/2 method. It was found that the reaction is a neutral electron demand type with matrix element control and the reactivity, the regio- and stereo-selectivities can be correctly predicted based on interaction energies calculated with the 4-center FMO formalism.

• 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.

• 한국자기공명학회논문지
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• 제8권1호
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• pp.62-69
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• 2004

Bicyclolactones obtained from the Diels-Alder cycloaddition of 3,5-dibromo-2-pyrone can undergo various palladium catalyzed cross coupling reactions to afford aryl bicyclolactones. The resulting coupled products can be readily converted into various 3-OH cyclohexenes via lactone ring openings, while those bearing dienyl units underwent highly diastereoselective Diels-Alder cycloadditions with selected dienophiles to funish multiply functionalized polycarbocycles. Bromo-bicyclic diene furnished two different diastereomers endo-form (62%) and exo-form (38%) upon cycloadditions with N-Et maleimide (NEM), and their stereochemistries were identified with NMR.

• Bulletin of the Korean Chemical Society
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• 제17권9호
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• pp.849-853
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• 1996

Hetero Dieis-Alder reactions containing phosphorus atom at various positions of diene and dienophile as well as standard Dieis-Alder reaction between ethylene and cis-l,3-butadiene have been studied using ab initio method. Activation energy showed a good linear relationship with the FMO energy gap between diene and dienophile, which can be normally used to explain Dieis-Alder reactivity. Since π-bond cleavage and σ-bonds formation occur concertedly at the TS, geometrical distortion of diene and dienophile from the reactant to the transition state is the source of barrier. Based on the linear correlations between activation barrier and deformation energy, and between deformation energy and π-bond order change, it was concluded that the activation barrier arises mainly from the breakage of π-bonds in diene and dienophile. Stabilization due to favorable orbital interaction is relatively small. The geometrical distortions raise MO levels of the TS, which is the origin of the activation energy. The lower barrier for the reactions of phosphorus containing dienophile (reactions C, D, and E) can be explained by the electronegativity effect of the phosphorus atom.

• Bulletin of the Korean Chemical Society
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• 제31권3호
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• pp.727-730
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• 2010

• Bulletin of the Korean Chemical Society
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• 제4권1호
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• pp.41-44
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• 1983

The chlorine addition and Diels-Alder cycloaddition of cyclopentadiene to 1, 4-benzoquinone-4-(O-methyloxime) have been studied MO theoretically. It has been shown that the reactions occur predominantly to the quinone ring double bond which is oriented anti to the nitrogen lone pair due to an n-${\sigma}^*$ interaction between the nitrogen lone pair, n, and the app. vicinal bond, causing the ${\pi}$ bond to be weakened and destabilized due to the less conjugation from reduced delocalization.