• Bulletin of the Korean Chemical Society
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• 제16권9호
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• pp.805-808
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• 1995

Diacetone-D-glucose was converted into 5-azido-6-O-benzoyl-3-O-benzyl-5-deoxy-1,2-O-isopropylidene-α-D-glucofuranose. After removal of isopropylidene and benzoyl protecting groups, hydrogenation performed reduction of azide and subsequent cyclization by reductive amination to give 3-O-benzyl-1-deoxy nojirimycin in high yield. The second azide group was introduced on 2-carbon by selective substitution reaction, and reduction of azide to amino group gave titled compound.

• 대한화학회지
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• 제46권4호
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• pp.397-402
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• 2002

• Bulletin of the Korean Chemical Society
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• 제35권9호
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• pp.2694-2698
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• 2014

A multisegmented polystyrene (PS) with pH-cleavable ester and carbamate linkages was successfully synthesized by a combination of atom transfer radical polymerization (ATRP) and Cu(I)-catalyzed 1,3-dipolar cycloaddition of azide and alkynes (click chemistry). ATRP was employed to synthesize polystyrene from hydroxyl-terminated initiator using CuBr/N,N,N',N",N"-pentamethyldiethylenetriamine (PMDETA) as the catalyst. The reaction of the resulting PS with sodium azide yielded the azido-terminated polymer. The hydroxyl group in the other end of the polymer was reacted with 4-nitrophenyl chloroformate (NPC), followed by reaction with propargylamine to produce an alkyne end group with a carbamate linkage. The PS with an alkyne group in one end and an azide group in the other end was then self-coupled in the presence of CuBr/2,2'-bipyridyl (bpy) in DMF to yield a desired multisegmented PS. Molecular weight and molecular weight distribution of the self-coupled polymer increased with time, as in the typical step-growth-type polymerization processes. Finally, we demonstrated that the ester and carbamate linkages of the multisegmented PS were hydrolyzed in the presence of HCl to yield individual PS chains.

• 대한화학회지
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• 제22권3호
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• pp.150-157
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• 1978

N-(p-nitrophenyl)-benzohydrazonyl azide (p-$CH_3,\;p-CH_3O,\;p-NO_2$, p-Cl, p-Br) 유도체들의 가수분해 반응 속도상수를 $25^{\cicr}C$의 50% dioxane 수용액속에서 자외선 분광광도법으로 측정하여 넓은 pH 범위에서 잘맞는 반응속도식을 구하였다. 위 반응속도식과 가수분해 반응속도에 미치는 치환기 효과를 검토하기 위하여 Hammet의 식에 도시한 결과 pH 5.0 이하에서는 $\rho$ = -0.47을, pH 7.0 이상에서는 $\rho$ = 0.68을 얻었다. 또한 반응속도에 미치는 염의 효과, 용매효과, 그리고 azide ion 효과로부터 이 가수분해 반응은 pH 5.0 이하에서는 $S_N1$ 반응, pH 7.0 이상에서는 hydrazonyl azide에 hydroxide 이온이 직접 반응하는 $S_N2$ 반응이 일어나며 pH 5.0와 pH 7.0 사이에서는 이 두반응이 서로 경쟁적으로 반응함을 알 수 있었다.

• Bulletin of the Korean Chemical Society
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• 제31권4호
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• pp.781-788
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• 2010

Experimental and theoretical studies show that all covalent azides possess a nonlinear azide group. They also rationalize this remarkable structural feature. We have seen that the most important non-covalent contributions in the covalently bound azides system (X-N1-N2-N3) are the $\pi$-delocalization over the entire molecule and a strong negative hyperconjugation which donates electron density from the filled $\sigma$ (X-N1) orbital into the unfilled, antibonding $\pi^*$ (N2-N3) orbital. For transition metal azide complexes, a bent configuration and a small difference between the N-N bond lengths, generally the longer one being adjacent to the transition metal, were observed.

• Bulletin of the Korean Chemical Society
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• 제35권6호
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• pp.1605-1612
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• 2014

Copper(I)-catalyzed Huisgen cycloaddition of terminal alkynes with unmasked azidoamines derived from amino acids is described. The reported strategy provides a new entry to highly hindered ${\beta}$-amino 1,2,3-triazole derivatives bearing a gem-diaryl group, which are potentially valuable entities as molecular catalysts for asymmetric transformations.

• 공업화학
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• 제24권3호
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• pp.305-313
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• 2013

본 연구는 glycidyl azide polymer (GAP)계 에너지 함유 열가소성 폴리우레탄 탄성체(energetic thermoplastic polyurethane elastomers, ETPE)를 합성한 후 탄성체의 필름 제조 공정의 열처리 조건이 물성에 미치는 영향에 대하여 고찰하였다. GAP계 ETPE는 ATR-FTIR, DSC, 그리고 DMA를 이용하여 분석하였다. GAP계 ETPE의 물성에 대한 열처리 조건의 영향은 $80{\sim}130^{\circ}C$의 온도 범위에서 1 h과 24 h의 열처리 시간을 나누어 연구를 진행하였다. 1 h의 열처리 조건에서는 $130^{\circ}C$의 열처리 온도에서 그리고 24 h의 열처리 과정에서는 $105^{\circ}C$ 이상의 온도조건에서 아자이드기의 흡수대인 $2090cm^{-1}$ 피크의 감소가 관찰되었으며, methylene chloride와 dimethylformamide 용매에 대한 필름의 용해도 또한 감소하였다. 이것은 $100^{\circ}C$ 이상 열처리 온도조건이 아자이드기의 가교 부반응을 유도할 수 있음을 나타낸다. 또한 열처리 온도가 $80^{\circ}C$에서 $110^{\circ}C$로 증가함에 따라 온도변화에 따른 저장 탄성률 곡선의 고온 고무평탄 영역이 더 높은 온도까지 확장되었으며, 이 또한 가교반응의 결과이다.

• Journal of Pharmaceutical Investigation
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• 제37권2호
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• pp.73-78
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• 2007

The aim of this study was to investigate the absorption properties of ketoprofen. The in-situ perfusion model has advantages over in vitro models as it provides intact lymphatic and blood flow circulation. The absorption properties of six different concentrations of ketoprofen have been studied in single pass in-situ rat intestine model. $^{14}C-PEG$ 4000 was used as a permeability marker and the possibility of an energy dependent contribution to ketoprofen absorption was also Investigated using the metabolic inhibitor sodium azide. Three different concentrations of sodium azide were studied to examine its effect on absorption of ketoprofen from the rat intestine. The findings of this study suggest that mono-carboxylic type drugs like ketoprofen cause permeability changes in the intestine. This is shown by the increase in absorption of $^{14}C-PEG$ 4000 as the concentration of ketoprofen is increased. However, the trend for ketoprofen permeability is to decrease over the concentration ranges. It was observed that the Papp values for ketoprofen with sodium azide shows a trend towards reduction in the amount of ketoprofen absorbed from the rat intestine which was significantly different (p<0.05) from that of ketoprofen with sodium azide 3.0mM. This indicates that sodium azide has an affect on the absorption of ketoprofen. The pH of all the perfusion solutions was altered to ${\sim}pH\;6.7$ by the buffering capacity of the small intestine secretions. The results suggest that mechanisms other than passive diffusion may be involved in ketoprofen absorption. This would be consistent with the involvement of active transport or saturatable processes in the absorption of drugs containing monocarboxylic acid group, as has been previously suggested from in vitro data.

• Macromolecular Research
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• 제15권6호
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• pp.541-546
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• 2007

The combination of atom transfer radical polymerization (ATRP) and click chemistry was employed for the efficient preparation of well-defined block copolymers. Bromo terminated poly(methyl acrylate) (pMA-Br) was prepared by an ATRP initiator, ethyl-2-bromoisobutyrate (EBiB). Subsequently, the bromine chain end of pMA-Br was converted to an azide group by simple nucleophilic substitution reaction. ${\alpha}-Alkyn-{\omega}-bromo-functionalized$ polystyrene was also synthesized by ATRP using the alkyn-functionalized initiator, propargyl-2-bromoisobutyrate (PgBiB). In both cases, the conversion was limited to a low level to ensure a high degree of chain end functionality. Then the coupling reaction between the azide end group in $pMA-N_3$ and alkyn-functionalized PgBiB-pSt was performed by Cu(I)catalysis. This coupling reaction was monitored by gel permeation chromatography (GPC). The synthesized block copolymer was characterized by FT-IR, $^1H-NMR$ spectroscopy and $^1H-^1H$ COSY correlation spectroscopy.

• 한국추진공학회:학술대회논문집
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• 한국추진공학회 2008년도 제31회 추계학술대회논문집
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• pp.231-236
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• 2008

양이온 개환중합법을 이용하여 Epichlorohydrin(ECH)과 Tetrahydrofuran(THF)을 공중합 하였다. 중합은 1,4-Butandiol 존재 하에 $BF_3THF$를 촉매로 사용하여 잘 제어된 Copolyetherdiol을 합성하였다. 분자량은 [monomer]/[diol]비를 조절하였고, 공중합체 조성은 ECH와 THF의 투입몰비를 변화하여 조절하였다. 합성된 Copolyetherdiol의 Chlorine기는$S_N2$반응을 이용하여 Azide기로 치환하였다. 합성된 고분자를 프리폴리머로 사용하여 경화제인 N-100/IPDI와 경화촉매인 TPB/MA 혼합촉매를 이용하여 Polyurethane을 합성하여 경화거동과 기계적 특성은 비교 분석하였다.