• 대한화학회지
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• 제39권8호
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• pp.657-665
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• 1995

여러가지 비대칭 벤질 에테르들과 벤질 알킬 에테르들을 $CH_3CO_2Et$-NaOCI수용액(6.6 mol eq.)의 2상 용매계에서 4-methoxy-2, 2, 6, 6,-tetramethylpiperidine-1-oxyl(0.03 mol eq., 4-methoxy-TEMPO)을 이용하여 산화시키면 벤조에이트로 산화가 일어난다. 4-methoxy-TEMPO는 2차 산화제인 NaOCI에 의하여 본반응의 산화제인 N-oxo-4-2, 2, 6, 6, -tetramethyl-piperidium 염(N-oxoammonium 염)으로 변환된다. N-oxoammonium 염은 에테르를 산화시키고 N-hydroxy-4-methoxy-2, 2, 6, 6,-tetramethylpiperidine(hydroxyamine)으로 환원된다. Hydroxy-amine은 NaOCI에 의하여 N-oxoammonium 염으로 순환 재생되므로 4-methoxy-TEMPO는 촉매량 사용하였다. 이 반응은 또한 조촉매인 KBr(0.03 mol eq.)가 필수적이고 반응 중 pH는 8.0 이하로 유지되어야 한다. 0 - 5$^{\circ}C$의 반응 온도로 2.5시간 반응시키면 대부분 벤조에이트로 산화 되었다. 벤질 알킬 에테르들의 선택성 산화는 수소의 산도와 알킬기의 입체효과에 영향을 받음이 고찰되었다.

• 한국결정학회지
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• 제6권2호
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• pp.103-110
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• 1995

1-Cyclopropyl-7-(2,7-diazabicyclo[3.3.0]oct-4-en-7-yl)-6-fluoro-8-methoxy-4-oxo-1,4-dihydroquinoline-3-carboxylic acid (HCI salt)의 분자 및 결정 구조를 X-선 회절법으로 연구하였다. 이 결정의 분자식은 C20H21N3O4FCl(이하 CDD), 결정계는 단사정계이고 공간군은 C2/c이다. 단위포상수 a=28.349(2)Å, b=11.941(2)Å, c=12.806(2)Å이며 β=96.428(9)°, V=4307.8Å3, T=296(2)K, Z=8이다. 구조해석에 사용한 X-선은 CuKα선(λ=1.5418Å)을 사용하였다. 분자구조는 직접법으로 풀었으며, 최소자승법으로 정밀화하였다. 최종 신뢰도 R값은 F0>4σ(F0)인 2258개의 독립 회절데이타에 대해 R=4.96%이었다. 이 분자는 내부수소결합 O(28)-H(28)…O(25) [2.517(4)Å, 156.7(447)°]를 가지고 있으며, 분자간의 결합은 van der Waals 힘으로 결합되어 있다.

• Bulletin of the Korean Chemical Society
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• 제31권12호
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• pp.3605-3610
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• 2010

In the present study, some quinoline derivatives have been synthesized like 8-methoxy-4-methyl-2-amino-(3'-chloro-2'-oxo-4'-substituted aryl-1'-azetidinyl)quinolines 8-12 and 8-methoxy-4-methyl-2-amino-(2'-substituted aryl-4'-oxo-1',3'-thiazolidin-3'-yl) quinolines 13-17 from 8-methoxy-4-methyl-2-(substituted arylidenyliminoamino)-quinolines 3-7. The structural assignments of these compounds were based on spectral (IR, $^1H$-NMR, Mass) and elemental (C, H, N) analysis. Further, these compounds were evaluated for antibacterial activity against various bacterial strains. Three compounds 10, 11 and 16 were found to exhibit potent antibacterial activity as compared to the standard drug amphicillin.

• Archives of Pharmacal Research
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• 제18권6호
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• pp.440-448
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• 1995

Fitty two flavones were synthesized from polyoxygenated dibenzoylmethanes which were obtained by a modified Baker-Venkatarman rearrangement, of 2-benzoyl oxyacetophenones. The following flavones among them showed good cytotoxic activities against L1210 and HL60 cells ; 2'-benzoyloxy-5,7-dimethoxyflavone $(8.2{\mu}g/ml,{\;}5.0 {\mu}g/ml)$, 2'-benzyloxy-5,7,8-trimethoxyflavone $(5,9 {\mu}g/ml,{\;}11.0{\mu}g/ml,{\;}2.7{\mu}g/ml)$, 2'-hydroxy-5,7,8-trimethoxyflavone $(9.8{\mu}/ml,{\;}6.2{\mu}g/ml)$, 2'-benzyloxy-5-hydroxyflavone $(5.2 {\mu}g/ml,{\;}3.6{\mu}g/ml)$, and 5,2'-dihydroxyflavone $(5.1{\mu}g/ml,{\;}4.0{\mu}g/ml)$. Presence of 5-methoxy group potentiated the cytotoxic activity, while the existence of 7-methoxy group decreased the activity. 5-Hydroxy or methoxy activates 4-carbonyl group, while 7-methoxy group deactivates the acrbonyl group. From these observation it was concluded that the activation of carbonyl group at C-4 of a flavone is important for the enahncement of the cytotoxic activity. The presence of both 5-hydroxy and 2-benzyloxy-or 2-hydroxy group enhanced the antitumor activity; 2'-benzyloxy-5-hydroxy-7-methoxyflaone 9T/C=144%), 5.2'-dihydroxy-7-methoxyflavone (T/C=132%) and 5,2'-dihydroxy-6,78,6' trtramethoxyflvone (T/C = 172%) 2'hexanolytion of 5,2'-dihydroxy-flavones did not improve the natitumor activity; 2' hexanoyloxy-5-hydroxy-7-methoxyflavone showed T/C = 132%, about the same as that of 5,2'-dihydroxy-7-methoxyflvone (T/C=130%)

• Bulletin of the Korean Chemical Society
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• 제21권8호
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• pp.793-796
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• 2000

In the neat flow vacuum pyrolysis of 2-methoxy-2-(o-N,N+dimethylaminomethyl)phenyl-3-trimethylsilyl-5,5-dime-thyl-2-silahexane (4) at $600^{\circ}C$ and its static thermolysis at $350^{\circ}C23-benzo-5-aza-1-silacyclohexane$, (5) has been obtained in97% and 46％ y ields, respectively. Product 5 might have been formed via an intramolecular rearrangement invoIving a zwitterionic species generated from the pentacoordinated silene Si-atom. From trapping experiments with an excess of MeOH, we have obtained 2-(o-N,N-dimethylaminomethyl)phenyl-5,5-dimethyl-2-trimethylsiloxy-2-silahexane (6) and 2-(o-N,N-dimethylaminomethyl)phenyl-2-methoxy-5,5-dime-thyl-2-silahexane (7) formed via an intermolecular protodesilylation reaction rather than through trapped prod-ucts of the silene.

• Natural Product Sciences
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• 제3권1호
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• pp.11-13
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• 1997

From the methanolic extract of defatted tender leaf of Camellia sinensis a new 4-hydroxy angular furocoumarin $C_{12}H_8O_5$, m.p. $212^{\circ}C$, was isolated using high-speed counter-current chromatographic technique. The structure of the compound was established as 4-hydroxy-2'-methoxy angular furocoumarin on the basis of physical methods viz. $^1H$ NMR, $^{13}C$ NMR and MS.

• 대한화학회지
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• 제10권4호
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• pp.149-152
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• 1966

鹽素置換 anisol과 chloral hydrate를 縮合하면 D.D.T 類의 合成에서와 같이 bis compound의 化合物이 生成될 것이고 D.D.T 系統의 化合物처럼 殺蟲能이 있으리라고 豫測되므로 4-chloro anisol 과 chloral hydrate를 縮合하여 生成物의 構造를 檢討하였던 바 2,2 bis(2-methoxy-5-chlorophenyl) 1.1.1-trichloroethane임을 確認하였으며 反應條件과 「국화꼬마수염진딧물」 및 「귤응애」에 대한 殺충能을 檢討한 結果 前報文$^{(67)}$에서 發表한 바 있는 化合物들의 殺蟲能에 比하여 5培나 强한 殺蟲能을 가졌다는 事實을 알았다.

• Archives of Pharmacal Research
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• 제20권2호
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• pp.194-196
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• 1997

A C-glycosyl chromone, named as 7-O-methylaloesinol, was newly isolated from the leaf exudate of Aloe capensis and identified as $8-C-{\beta}-D-glucopyranosyl$${\beta}-2-[2-(R)-hydroxypropyl]-7-methoxy-5-methyl-4H-1-benzopyran-4-one$ by chemical and spectral evidence.

• Bulletin of the Korean Chemical Society
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• 제8권2호
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• pp.96-101
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• 1987

2-Ethoxy-6-methoxy-5-cyano-3,4-dihydro-2H-pyran (1_a$), 2-n-butoxy-6-methoxy-5-cyano-3,4-dihydro-2H-pyr an (1b), 2-isobutoxy-6-methoxy-5-cyano-3,4-dihydro-2H-py ran ($1_c$), and 2-ethoxy-6-methoxy-3-methyl-5-cyano-3,4-dihydro -2H-pyran ($1_d$) were prepared by (4 + 2) cycloaddition reaction of methyl $\alpha$-cyanoacrylate with the corresponding alkyl vinyl ethers. Compounds $1_{a-d}$ were ring-open polymerized by cationic catalyst to obtain alternating head-to-head (H-H) copolymers. For comparison, head-to-tail (H-T) copolymer $3_a$ was also prepared by free radical copolymerization of the corresponding monomers. The H-H copolymer exhibited minor differences in its $1_H% NMR and IR spectra, but in the $^{13}C$ NMR spectra significant differences were observed between the H-H and H-T copolymers. Glass transition temperature ($T_g$) of H-H copolymer was higher than that of the H-T copolymer, but thermal decomposition temperature of the H-H copolymer was lower than that of the H-T copolymer. Compounds $1_a$, $a_b$, and $1_c$, copolymerized well with styrene by cationic catalyst, but compound 1d failed to copolymerize with styrene. All of the H-H and H-T copolymers were soluble in common solvents and the inherent viscosities were in the range 0.2-0.4 dl/g.

• 약학회지
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• 제39권1호
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• pp.36-40
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• 1995

In order to investigate the biological activity of protoberberine derivatives, they were synthesized four derivatives (1-4) of 7,8 adduct of cycloberberine, two derivatives (5, 6) treated with alkylamine or phenylamine, four compounds (7, 8) and (9, 10) adduct with 1,3-dichloroacetone and oxalychloride. Antibacterial activity of these synthesized compounds was tested.