• Journal of the Korean Chemical Society
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• v.53 no.1
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• pp.84-89
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• 2009

• Bulletin of the Korean Chemical Society
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• v.32 no.9
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• pp.3211-3212
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• 2011

• Journal of the Korean Chemical Society
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• v.43 no.3
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• pp.361-365
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• 1999

• Polymer(Korea)
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• v.36 no.3
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• pp.295-301
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• 2012

Efficient stitching methods for the synthesis of Fr$\acute{e}$chet-type dendrimers with linear PEG units at a core were elaborated. The synthetic strategy involved an inexpensive 1,3-dipolar cycloaddition reaction between an alkyne and an azide in the presence of Cu(I) species which is known as the best example of click chemistry. The linear core building blocks, two diazido-PEG units, were chosen to serve as the azide functionalities for dendrimer growth via click reactions with the alkyne-dendrons. These two building blocks were employed together with the alkyne-functionalized Fr$\acute{e}$chet-type dendrons in a convergent strategy to synthesize two kinds of Fr$\acute{e}$chet-type dendrimers with different linear core units.

• Macromolecular Research
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• v.17 no.6
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• pp.424-429
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• 2009

In this study, we demonstrate that the biological unnatural amino acid incorporation method can be utilized in vivo to synthesize an alkyne-terminated telechelic protein, Synthesis of terminally-functionalized polymers such as telechelic polymers is recognized to be important, since they can be employed usefully in many areas of biology and material science, such as drug delivery, colloidal dispersion, surface modification, and formation of polymer network. The introduction of alkyne groups into polymeric material is particularly interesting since the alkyne group can be a linker to combine other materials using click chemistry. To synthesize the telechelic recombinant protein, we attempted to incorporate the L-homopropargylglycine into the recombinant GroES fragment by expressing the recombinant gene encoding Met at the codons for both N- and C-terminals of the protein in the Met auxotrophic E. coli via Hpg supplementation. The Hpg incorporation rate was investigated and the incorporation was confirmed by MALDI-TOF analysis of the telcchelic recombinant protein.

• Bulletin of the Korean Chemical Society
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• v.31 no.12
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• pp.3583-3587
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• 2010

Furoxanthiols PFT and BPFT possessing thiomethyl or thiobenzyl groups in the furoxan ring were designed and synthesized as potential light-sensitive alkyne precursors on a gold surface. The synthesis of thiofuroxans PFT and BPFT was performed from the corresponding halofuroxans 1b and 2c, respectively, by the substitution with potassium thioacetate in ethyl acetate/ethanol or DMF, followed by basic hydrolysis as the key reactions. Electron-beammediated fragmentation of furoxans 1c and 2d in a mass spectrometer afforded the corresponding aryl alkyne fragments, with the evolution of NO in high preference. In the cases of thiofuroxans PFT and BPFT, carbon-sulfur bond cleavage was observed as a representative fragmentation, producing M-SH and M-SAc peaks, which competed with the release of NO. In the fragmentation of mono-aryl furoxan 1c, the release of molecule of NO was predominately observed to produce an M-NO fragment as a base peak by the formation of trimembered thiiranium or azirine intermediate.

• Polymer(Korea)
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• v.33 no.1
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• pp.67-71
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• 2009

The stitching method for the synthesis of $Fr\acute{e}chet$-type dendrimers was elaborated using click chemistry between an alkyne and an azide. The core building block, 4,4'-(3,5-bis(azidopropyloxy)benzyloxy)bisphenyl, was designed to serve as the azide functionalities for dendrimer growth via click reactions with the alkyne-dendrons. The synthetic strategy involved an 1,3-dipolar cycloaddition reaction between an azide and an alkyne-functionalized $Fr\acute{e}chet$-type dendrons in the presence of Cu(I) species which is known as the best example of click chemistry.

• Macromolecular Research
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• v.17 no.7
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• pp.499-505
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• 2009

General, fast, and efficient stitching methods are presented for the synthesis of Fr$\acute{e}$chet-type dendrimers with linear units at a core, as a preliminary investigation for the synthesis of dendritic-linear-dendritic materials. The synthetic strategy involved an inexpensive, 1,3-dipolar, cycloaddition reaction between an alkyne and an azide in the presence of the Cu(I) species, which is known as the best example of click chemistry. The linear core building blocks, 1,7-octadiyne and 1,6-diazidohexane, were chosen to serve as the alkyne and azide functionalities for dendrimer growth via click reactions with the azide and alkyne-dendrons, respectively. These two building blocks were employed together with the azide- and alkyne-functionalized Fr$\acute{e}$chet-type dendrons in a convergent strategy to synthesize two kinds of Fr$\acute{e}$chet-type dendrimers with different linear core units. This comparative efficiency of the click methodology supports the fast and efficient synthesis of dendritic-linear-dendritic materials with the tailor made core unit.

• Bulletin of the Korean Chemical Society
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• v.32 no.11
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• pp.3933-3940
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• 2011

General, fast, and efficient stitching methods for the synthesis of dendrimers with linear PEG units at a core, as dendritic-linear-dendritic materials, were developed. The synthetic strategy involved the click reaction between an alkyne and an azide. The linear core building blocks, three dialkyne-PEG units, were chosen to serve as the alkyne functionalities for dendrimer growth via click reactions with the azide-dendrons. These three building blocks were employed together with the azide-functionalized Fr$\acute{e}$chet-type dendrons in a convergent strategy to synthesize the Fr$\acute{e}$chet-type dendrimers with different linear core units. Their structure of dendrimers was confirmed by $^1H$ and $^{13}C$ NMR spectroscopy, IR spectroscopy, mass spectrometry, and GPC analysis.

• Journal of the Korean Chemical Society
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• v.51 no.2
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• pp.160-164
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• 2007

Aminofuroxan derivatives 3 and 4 were prepared by the reaction of chlorofuroxan 2 with butyl and benzyl amines, respectively. E-beam mediated fragmentation of aminofuroxans 3, 4 in mass spectrometer was analyzed in a view of the corresponding alkyne formation.