• 대한화학회지
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• 제47권3호
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• pp.229-236
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• 2003

Cyclobutenedions을 lithium trimethylsilylacetylene과 반응시키고 물로 반응을 정지시키면 butenolides가 생성된다. 이 색다른 반응을 위해 allene을 intermediate로 하는 기전을 제안하였다. 이는 trimethylsilyl group이 너무 크기 때문에 보통의 diradical intermediate는 형성이 어렵고, allene이 ${\alpha}$-silyl group에 의해 안정화되기 때문이라고 사료된다.

• Bulletin of the Korean Chemical Society
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• 제28권11호
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• pp.1921-1922
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• 2007

• BMB Reports
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• 제46권3호
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• pp.151-156
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• 2013

Phylogenetic and amino acid sequence analysis indicated that rice allene oxide synthase-1 (OsAOS1) is CYP74, and is clearly distinct from CYP74B, C and D subfamilies. Regio- and stereo-chemical analysis revealed the dual substrate specificity of OsAOS1 for (cis,trans)-configurational isomers of 13(S)- and 9(S)-hydroperoxyoctadecadienoic acid. GC-MS analysis showed that OsAOS1 converts 13(S)- and 9(S)-hydroperoxyoctadecadi(tri)enoic acid into their corresponding allene oxide. UV-Visible spectral analysis of native OsAOS1 revealed a Soret maximum at 393 nm, which shifted to 424 nm with several clean isobestic points upon binding of OsAOS1 to imidazole. The spectral shift induced by imidazole correlated with inhibition of OsAOS1 activity, implying that imidazole may coordinate to ferric heme iron, triggering a heme-iron transition from high spin state to low spin state. The implications and significance of a putative type II ligand-induced spin state transition in OsAOS1 are discussed.

• 대한화학회지
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• 제23권5호
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• pp.314-319
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• 1979

바닥 말무리 dinoflagellate의 광합성 에너지 수용 색소인 peridinin의 전자 흡수스펙트럼을 PPP SCF MO 계산결과와 형광 편광 실험결과에 견주어 분석하였다. 청색광 부위의 흡수띠 (470 nm)는 $B{\leftarrow}A$ 천이에 대응하여 분자의 장축과 거의 평행 방향으로 편광되어 있음이 예측된다. 소위 "cis peak" 영역의 근자외선 흡수띠는 두개의 비교적 약한 ${\pi}{\rightarrow}{\pi}^*$천이 $(C{\leftarrow}A$와 $D{\leftarrow}A)$에 기인하며 그 편광축은 $^1B{\leftarrow}A$편광축 방향과 근접되어 있음이 MO 계산과 편광 측정에 의해 추정되었다. 그리고 락톤 카르보닐 원자단의 전자구조는 $^1B$ 상태에서도$^1A$ 상태 (ground state)에 비해서 과히 변화함이 없으나, allene기는 charge transfer적 성격을 농후하게 띠고 있어서 들뜬상태에서는 allene기가 전자결핍상태가 되는 것이 예측된다.

• Bulletin of the Korean Chemical Society
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• 제32권spc8호
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• pp.2873-2874
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• 2011

• Bulletin of the Korean Chemical Society
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• 제29권2호
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• pp.487-490
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• 2008

• Applied Biological Chemistry
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• 제1권
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• pp.43-47
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• 1960

1). By means of the F.H. Allene and James Allenes method of the ${\alpha}-methylindole$ synthesis, 2-methylindole was prepared with the Acetyl-o-toluidine and $NaNH_2$. yield; 88%, mp. $56.5{\sim}57^{\circ}C$. 2). 23.7 gr of 3-(-Nitro-1-phenylethyl)-2-melthylindole was prepared with 0.1 mol. of the 2-methylindole and 0.1 mol. of the ${\beta}-Nitrostyrene$. yield: 84.6%, mp. $104{\sim}105^{\circ}C$. 3). Analytical results. Calcd. for $C_{17}H_{16}N_2O_2$: C, 72.84; H, 5.63; N, 9.99. Found: C, 72.62; H, 5.63; N, 9.79.

• 대한화학회지
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• 제31권2호
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• pp.133-142
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• 1987

시클로로펜타디엔과 메틸기로 치환된 알렌의 산 및 에스테르간의 (4+2)고리화반응에서 입체 선택성을 $\pi$-비결합상호작용($\pi$-NBI)을 적용하여 고찰하였다. 열반응에서는 diene(LUMO)-dienophile (HOMO)만을 고려한 2-FMO방법이, 산촉매반응에서는 diene (HOMO)-dienophile (LUMO)상호작용만을 고려한 2-FMO방법이 이들의 입체선택성의 결정에 중요하였다. cumulated diene계의 친디엔체에서 메틸 치환기는 알렌구조와 through-bond 상호작용에 의해 $\pi$-isoconjugate diene 구조를 형성하여 컨쥬게이션기로 작용하며 FMO의 에너지에 narrowing effect를 주고 있으나 이같은 $\pi$-isoconjugated diene 구조를 만들 수 없는 친디엔체에서는 메틸기가 단순히 전자주는기로 작용한다. 열반응에서 입체선택성은 에틸렌 분자와 마찬가지로 메틸 치환기의 $\pi$-비결합 2차궤도 상호작용($\pi$-NSOI)에 의해서 좌우되었다.

• Natural Product Sciences
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• 제13권4호
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• pp.365-368
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• 2007

Bioactivity-guided fractionation of MeOH extract of an association of two sponges, Jaspis sp. and Poecillastra sp. resulted in isolation of four apocarotenoids (1 - 4). Their structures were determined on the basis of MS and NMR spectroscopic analyses and by direct comparison with those of reported. This is the first report on isolation of these compounds from any sponge. Isolated metabolites were evaluated for cytotoxicity against a small panel of solid human tumor cell lines.

• Bulletin of the Korean Chemical Society
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• 제35권9호
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• pp.2717-2722
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• 2014

The reaction mechanism between azacyclopropenylidene and epoxypropane has been systematically investigated employing the second-order M${\o}$ller-Plesset perturbation theory (MP2) method to better understand the reactivity of azacyclopropenylidene with four-membered ring compound epoxypropane. Geometry optimization, vibrational analysis, and energy property for the involved stationary points on the potential energy surface have been calculated. It was found that for the first step of this reaction, azacyclopropenylidene can insert into epoxypropane at its C-O or C-C bond to form spiro intermediate IM. It is easier for the azacyclopropenylidene to insert into the C-O bond than the C-C bond. Through the ring-opened step at the C-C bond of azacyclopropenylidene fragment, IM can transfer to product P1, which is named as pathway (1). On the other hand, through the H-transferred step and subsequent ring-opened step at the C-N bond of azacyclopropenylidene fragment, IM can convert to product P2, which is named as pathway (2). From the thermodynamics viewpoint, the P2 characterized by an allene is the dominating product. From the kinetic viewpoint, the pathway (1) of formation to P1 is primary.