• Bulletin of the Korean Chemical Society
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• 제29권9호
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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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• 제22권8호
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• pp.791-792
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• 2001

• Bulletin of the Korean Chemical Society
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• 제29권4호
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• pp.755-757
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• 2008

A short and highly efficient synthetic method to prepare synthetically useful tetrahydroindolizinone derivatives from the ring-closing metathesis of N-allyl-5-allyl-5-hydroxylactams is described.

• Bulletin of the Korean Chemical Society
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• 제25권8호
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• pp.1280-1282
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• 2004

• Bulletin of the Korean Chemical Society
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• 제30권5호
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• pp.1147-1151
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• 2009

The synthetic route of novel 3′-C-methyl carbodine analogue is described. The construction of tertiary alcohol at 3′- position of carbodine analogues was successfully made via sequential [3,3]-sigmatropic rearrangement, ring-closing metathesis (RCM) and stereoselective dihydroxylation reactions starting from ethyl glycolate.

• Bulletin of the Korean Chemical Society
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• 제29권10호
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• pp.2057-2060
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• 2008

• Bulletin of the Korean Chemical Society
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• 제32권4호
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• pp.1146-1152
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• 2011

The discovery of 2'-spirocyclopropyl-ribocytidine (J. Med. Chem. 2010, 53, 8150-8160) as a potent inhibitor of RNA synthesis by NS5B ($IC_{50}=7.3{\mu}M$), the RNA polymerase encoded by hepatitis C Virus (HCV), has led to the synthesis and biological evaluation of several carbocyclic versions of 2'-spiropropyl-nucleosides. The cyclopentenol intermediate 7 was successfully constructed via ring-closing metathesis (RCM) from divinyl 6. Spirocyclopropanation of enone 8 was effected by using (2-chloroethyl)-dimethylsulfonium iodide and potassium tert-butoxide to form the desired intermediate 9. The synthesized nucleoside analogues 21-24 were assayed for their ability to inhibit HCV RNA replication in a subgenomic replicon Huh7 cell line. Among them, the cytosine nucleoside analogue 22 exhibited significant anti-HCV activity ($EC_{50}= 8.2{\mu}M$).

• Bulletin of the Korean Chemical Society
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• 제33권11호
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• pp.3895-3898
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• 2012

• Bulletin of the Korean Chemical Society
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• 제22권11호
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• pp.1179-1180
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• 2001

• Bulletin of the Korean Chemical Society
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• 제35권12호
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• pp.3627-3631
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• 2014

In this study we examined two ester-containing cross-links, hex-2-enyl acetate and hex-2-enyl propionate, as new cross-linking systems for helix stabilization of short peptides. We demonstrated that these hexenyl ester cross-links can be readily installed via a ruthenium-mediated ring-closing metathesis reaction of L-aspartic acid 4-allyl ester or L-glutamic acid 5-allyl ester at position i and (S)-2-(4'-pentenyl)alanine at position i+4 using second generation Hoveyda-Grubbs catalyst at $60^{\circ}C$. Between these two cross-links, we found that the hex-2-enyl propionate significantly stabilizes the ${\alpha}$-helical conformations of short model peptides. The helix-stabilizing effects of the hex-2-enyl propionate tether appear to be as powerful as Verdine's i,i+4 all-hydrocarbon stapling system, which is one of the most widely used and the most potent helix-stabilizing cross-linking systems. Furthermore, the hex-2-enyl propionate bridge is reasonably robust against non-enzymatic hydrolytic cleavage at a physiological pH. While extended studies for probing its chemical scopes and biological applications are needed, we believe that this new helix-stabilizing system could serve as a useful chemical tool for understanding protein folding and designing conformationally-constrained peptide drugs.