• 제목/요약/키워드: Regioselective cleavage

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Total Synthesis of Sufentanil

  • Shin, Dong-Yun;Ryu, Jae-Sang;Hyun, Soon-Sil;Park, Hyun-Ju;Jeon, Ra-Ok;Suh, Young-Ger
    • Archives of Pharmacal Research
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    • 제22권4호
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    • pp.398-400
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    • 1999
  • Sufentanil, a potent anilidopiperidine analgesic, was synthesized from a simple thiophenylethylamine via six sequence. The key parts of this synthesis involved an efficient construction of thiophenylethylpiperidone by aminomethano desilylation-cyclization followed by Swern oxidation and a direct regioselective N-nucleophilic spiral epoxide cleavage with aniline promoted by Lewis acids.

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Stereoselective Total Synthesis of (-)-Cytoxazone

  • Kim, Ji-Duck;Hoon, Jung-Young
    • 대한약학회:학술대회논문집
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    • 대한약학회 2003년도 Proceedings of the Convention of the Pharmaceutical Society of Korea Vol.2-2
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    • pp.179.2-179.2
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    • 2003
  • We have developed the novel one-pot synthetic method for regioselective and stereoselective N-protected amines through the reaction of various ethers with chlorosulfonyl isocyanate (CSI). Also, we found a novel technique to compare directly the stability of carbocations in the solution phase and established the stability order of the various carbocations. And we reported the cleavage of benzyl and p-methoxybenzyl protecting groups of alcohols and phenols in the presence of other functional groups using CSI. (omitted)

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프로토베르베린 관련 화합물합성 및 항균작용 (Synthesis of Protoberberine Related Compounds and Their Antifungal Activities)

  • 김신규;김동현;정경희;황순호;김재현
    • 약학회지
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    • 제38권1호
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    • pp.91-96
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    • 1994
  • Irradiation of the berberinephenolbetaine [1] effected valence tautamerization to five 8,14-cycloberbine[21, which was converted to the spirobenzylisoquinolines by regioselective C-N bond cleavage A variety of ring systems such as compounds [4], [5] and [6] were introduced by the structural modification of berberinephenolbetaine.

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벤조펜안드리딘과 관련된 알칼로이드의 합성 (Synthesis of Benzophenanthridine-Related Alkaloids)

  • 김신규;이형원;김인종;이마세
    • 약학회지
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    • 제36권3호
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    • pp.250-254
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    • 1992
  • Benzo[C]phenanthidine alkaloids were found to exhibit considerably strong antileukemic activies. These alkaloids have been shown to be biosynthesized from the corresponding alkaloids throung an oxidative $C_6-N$ bond cleavage followed by recyclization between $C_6\;and\;C_{13}$ position of the protoberberine. Recently we have achieved the biomimetic transformation of protoberberine alkaloid, berberine into benzo[C]phenanthridine alkaloid, chelerythrine.

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Selective Reduction of Orgainc Compounds with Al-Fluorodiisobutylalane

  • 차진순;박성진
    • 통합자연과학논문집
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    • 제2권3호
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    • pp.185-189
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    • 2009
  • The new MPV-type reagent, Al-fluorodiisobutylalane (DIBAF), has been prepared and their reducing characteristics in the reduction of selected organic compounds containing representative functional groups have been examined in order to find out a new reducing system with unique applicability in organic synthesis. In general, the reagent is extremely mild, showing only reactivity toward aldehydes, ketones, and epoxides. The reagent achives a clean 1,2-reduction of enals to the corresponding allylic alcohols in a 100% purity, but shows no reactivity toward enones. The reagent also shows an excellent regioselective cleavage of substituted epoxides. In addition, DIBAF produces the thermodynamically more stable alcohol epimer in high stereoselectivity in the reduction of cyclic ketones.

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Selective Reduction of Organic Compounds with Al-Trifluoromethanesulfonyldiisobutylalane. Comparison of Its Reactivity with Al-Methanesulfonyldiisobutylalane

  • Cha, Jin-Soon
    • Bulletin of the Korean Chemical Society
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    • 제32권1호
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    • pp.219-224
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    • 2011
  • The new MPV type reagent, Al-trifluoromethanesulfonyldiisobutylalane ($DIBAO_3SCF_3$), has been prepared and its reducing characteristics in the reduction of selected organic compounds containing representative functional groups have been examined, and compared its reactivity with that of Al-methanesulfonyldiisobutylalane ($DIBAO_3SCH_3$) in order to understand the fluorine-substituent effect on its reactivity. In general, the reactivity of $DIBAO_3SCF_3$ appears to be much higher than that of $DIBAO_3SCH_3$, apparently due to the acidity increase by the electron-withdrawing fluorine-substituent. The reagent reduced aldehydes and ketones readily, but showed a perfect selectivity in the reduction of $\alpha,\beta$-unsaturated aldehydes and ketones to produce the corresponding allylic alcohols in an absolutely 100% purity. In addition, the reagent achieved the regioselective cleavage of phenyl- or/and alkyl-substituted epoxides to the less substituted alcohols in a perfect regioselectivity. Moreover, the reagent also showed an high stereoselectivity in the reduction of substituted cycloalkanones to produce the thermodynamically more stable alcohol epimers exclusively.

Protoberberine의 고급지방산 유도체합성 및 활성연구(V) (Synthesis of Protoberberine Derivatives and Their Biological Activities)

  • 김신규;권창호;육창수;노영수;서성훈;정세영;정성현;김동현;황순호
    • 약학회지
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    • 제36권1호
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    • pp.1-6
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    • 1992
  • Irradiation of phenolbetaine in a stream of nitrogen produced 8,14-cycioberbine[1]. Compound[1] was treated with 10% HCl solution to give the 8-hydroxycycloberbine[2] in 67.7% yield. Subsequently addition of ethylchloroformate to the compound[2] gave rise to the 8-hydroxy-7-ethylcarboxy-9, 10-dimethoxy-2, 3-methylenelioxy-13-oxo-norochotensane[3] in 78% yield. Treatment of the compound[3] with bis-(2-chloroethyl)amine then lead to the 7-bis(2-chloroethyl)carbamyl-norochoteneare[4]. On the other hand the compound[5], which is the 8-methoxynorochotensane, was derived when compound[1] was treated with methanol in a few drops of BF. Treatment of the compound[6], and the compound[7], 7-bis(2-chloroethyl)-carbanyl-8-methoxy-norocheyensane, was then synthesized by reaction of the compound[6] with bis(2-chloroethyl) amine. In the other synthetic pathway when compound[5] was treated with $POCl_3$ in dried benzene, 13-chloro-6-ene-norochetensane[8] with 42% yield was formed. Finally the 13-bis-(2-chloroethyl) amino-8-methoxy-norochotensane[9] was produced when we treated the compound[8] with bis-(2-chloroethyl) amine. In another pathway, reaction between phenolbetaine which is the precursor of the compound[1] and benzoylchloride in dried chloroform gave us the 5,6,7 trihydro-2, 3-methylene-dioxy-9-chloromethyl-10, 11-dimethoxyphenylisoquinoline-8-benzoate[10] in 73% yield. The results of biological activities for these compounds are also presented in Table I and II.

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