• Archives of Pharmacal Research
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• v.27 no.2
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• pp.136-142
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• 2004

In this study, a highly diastereoselective synthesis of anti-1 ,2-aminoalcohol was explored starting from L-amino acids as chiral sources. The higher yield and diastereoselectivity was shown when the aza-Claisen rearranqement was performed with allylic trichloroacetimidate 6a in the presence of palldium(II) catalyst.

• Bulletin of the Korean Chemical Society
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• v.10 no.5
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• pp.465-466
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• 1989

• Bulletin of the Korean Chemical Society
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• v.28 no.9
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• pp.1545-1548
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• 2007

This paper discusses the racemic and stereoselective synthetic route for novel 4'α -methyl and 6'α -methyl analogues of abacavir. The quaternary carbon at the 4'-position of carbocyclic nucleoside was installed successfully via a Claisen rearrangement. The stereocontrolled construction of a methyl group in the 6'α - position was directed through the Felkin-Anh rule. A Bis-vinyl compound 9 was cyclized successfully using Grubbs' catalyst II to provide a carbocycle nucleus for the target compound. The synthesized compound 15 showed moderate anti-HIV activity (EC50 = 10.67 μM, MT-4 cell lines).

• Archives of Pharmacal Research
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• v.28 no.2
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• pp.129-141
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• 2005

(-)-Fumagillol (1), a hydrolysis product of fumagillin, has been synthesized by several group from commercially available 1,2:5,6-di-O-isopropylidene-${\alpha}$-D-allofuranose in a highly stereoselective manner. Chiral centers on C5 and C6 came from D-allofuranose and the asymmetric center on C4 was accomplished by 1,3-chirality transfer using the Claisen rearrangement on a chiral allyl alcohol. Chirality, which is necessary on an epoxide consisting of the spiro-ring system, was diastereoselectively constructed by the well-known reaction, intramolecular ester enolate alkylation (IEEA), which showed that this reaction can be applied to the alpha-alkoxy ester system. The epoxide on the side chain was regioselectively introduced by the difference between the number of substituents on the vinyl groups. This accomplishment proved that IEEA can be a useful tool for the synthesis of complex molecules.

• Bulletin of the Korean Chemical Society
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• v.30 no.12
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• pp.2959-2961
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• 2009

Total synthesis of (${\pm}$)-licochalcone E (1), an allyl retrochalcone isolated from roots of Glycyrrhiza inflata, has been achieved from 4-tetrahydropyranyloxyacetophenone (7) with (E)-2-methoxy-4-(2-methyl-2-butenyloxy)benzaldehyde (6) or (Z)-2-methoxy-4-(2-methyl-2-butenyloxy)-benzaldehyde (11) through a convergent strategy involving aldol condensation and Claisen rearrangement as key steps.

• Bulletin of the Korean Chemical Society
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• v.29 no.9
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• pp.1723-1728
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• 2008

An efficient synthetic route for carbocyclic versions of stavudine analogues and their evaluation on antiviral activity are described. The construction of an ethynylated quaternary carbon at the 4'-position of carbocyclic nucleosides was accomplished using Claisen rearrangement of 11 and ring-closing metathesis (RCM) of dienyne 14 as key transformations. An antiviral evaluation of the synthesized compounds, 20, 21, 22, and 25 against HIV-1, HSV-1, HSV-2, and HCMV showed that only the guanine analogue 25 is moderately active against HIV-1 in the MT-4 cell line ($EC_{50}$ = 11.91 $\mu$mol).

• Bulletin of the Korean Chemical Society
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• v.35 no.7
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• pp.1996-1998
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• 2014

Licochalcone C was synthesized from commercially available 2,4-dihydroxybenzaldehde by using regioselective $Al_2O_3$-mediated C-prenylation followed by conventional Claisen-Schmidt condensation in basic condition.

• Bulletin of the Korean Chemical Society
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• v.34 no.7
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• pp.1949-1950
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• 2013

• Bulletin of the Korean Chemical Society
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• v.22 no.2
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• pp.139-140
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• 2001

• Proceedings of the PSK Conference
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• 2001.10a
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• pp.230.2-230.2
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• 2001