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The Linear Free Energy Relationship in Cinnamonitrile Derivatives

  • Shim, Sang-Chul;Yoon, Suk-Kyoon
    • Bulletin of the Korean Chemical Society
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    • 제2권4호
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    • pp.147-151
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    • 1981
  • Chemical shift differences of vinyl protons of cis- and trans-cinnamonitrile derivatives are very well correlated with $({\sigma}_I, {\sigma_R^0})$, ${\sigma}_P^+$, and (F, R) (r = 0.9996-0.8946), much better correlation than the case of methyl cinnamates. para-Substituted and trans-cinnamonitrile derivatives have larger resonance contribution than meta-substituted and cis-derivatives.

Theoretical Analysis of Dipole Moment Derivatives in Fluoromethanes. (II) Difluoromethane

  • Kim, Kwan
    • Bulletin of the Korean Chemical Society
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    • 제8권1호
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    • pp.10-15
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    • 1987
  • The results of an ab initio (6-31G) molecular orbital calculation of the dipole moment derivatives and gas phase IR intensities of difluoromethane are reported. The results are compared with corresponding values obtained from a CNDO calculation. The directions of the dipole derivatives calculated by the two methods agree very well, whereas the intensities differ significantly. The results are also analyzed for the charge-charge flux-overlap electronic contributions to the dipole derivatives.

Preparation of Polyenaryloxynitriles from Dicyanovinyl Chloride and Diphenol Derivatives in the Presence of DABCO

  • 금네리;공명선
    • Bulletin of the Korean Chemical Society
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    • 제21권11호
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    • pp.1111-1114
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    • 2000
  • The kinetic study of the enaryloxynitriles via the nucleophilic vinylic substitution reaction of various phenol derivatives with 1-chloro-1-phenyl-2,2-dicyanoethene (1) was conducted in the presence of 1,4-diazabicyclo[2,2,2]octane (DABCO). Nucleo philic vinylic substitution of phenol derivatives with electrophilic olefins carrying sluggish leaving group involves a third-order reaction. The reaction was applied to solution polymerization of diphenol derivatives with p-bis(1-chrolo-2,2-dicyanovinyl)benzene (2), which yielded various polyenaryloxynitriles with moderate molecular weight.

Stabilization of Poly(dA)-[poly(dT)]₂Triplex by Anthryl and Acridine Derivatives: Effect of Side Chains and Nitrogen Atom on the Polycyclic Aromatic Ring

  • 이길준;조창범;이동진;박준원;Kim, Seog K.
    • Bulletin of the Korean Chemical Society
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    • 제20권6호
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    • pp.653-656
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    • 1999
  • The effects of anthryl derivatives and 9-aminoacridine on the thermal melting profile of a poly(dA)[poly(dT)]₂triplex were compared 9-Aminoacridine stabilizes the triplex far more effectively than anthryl derivatives. The absorption and CD and LD spectroscopic characteristics of anthryl derivatives are similar to those of 9-aminoacridine when complexed with the triplex; the N atom of acridine, which can act as a hydrogen bond acceptor, plays an important role in triplex stabilization.

담즙산류가 담즙배출에 미치는 영향 (The effect of several cholanic acid derivatives on bile secretion)

  • 홍사욱;박대성;한덕룡;이종철;홍사석
    • 약학회지
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    • 제16권4호
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    • pp.176-179
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    • 1972
  • The bile secretion was accelerated generally by the administration of all derivatives tested: chemodeoxycholate, deoxycholate, cholate, dehydrocholate, 7-ketochenodeoxycholate, and 3, 7-diketochenodeoxycholate in decreasing order. Bile acids content in bile from animals administered with cholate was increased, however, other derivatives did not alter the contents of bile acids and bilirubin. In view of pharmacological point, all derivatives have hydrocholeretic action, however, only cholate exhibits typical choleretic action.

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Synthesis of 3-[1-(t-Butyldimethylsilyloxy)ethyl]-4-carboxymethyl-2-azetidinone Derivatives

  • 서민효;이윤영;구양모
    • Bulletin of the Korean Chemical Society
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    • 제17권4호
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    • pp.314-321
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    • 1996
  • Isoxazolidine derivatives 7 and 8 were synthesized from N-benzyl-C-(2-benzyloxyethyl)nitrones by 1,3-dipolar cycloaddition with ethyl crotonate. The isoxazolidine derivatives were converted to β-amino acid esters 9a and 9b by reduction with zinc in acetic acid. The β-amino acid esters were reacted with methylmagnesium bromide to give the 2-azetidinones (13a, 13b). The benzyl group of 2-azetidinones were removed by Birch reduction. The products were oxidized with PDC to give 3-[1-(t-butyldimethylsilyloxy)ethyl]-4-carboxymethyl-2-azetidinone derivatives (2a, 2c).

芳香族 誘導體의 염素化反應 Ethyl-${\alpha},{\beta}-dichloro-{\beta}$-phenyl propionate의 gamma 線 鹽素化反應 (Chlorination of Phenyl Derivatives : Chlorination of ethyl -${\alpha},{\beta}-dichloro-{\beta}$-phenyl propionate under gamma ray irradiation)

  • 김유선;김기수
    • 대한화학회지
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    • 제12권2호
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    • pp.55-60
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    • 1968
  • 芳香族誘道體 化合物의 鹽素化反應을 紫外線照射 및 ${\gamma}$-線照射下에서 行하였던 바 ethyl,${\alpha} ,{\beta} -dichloro-{\beta}$-phenyl propionate의 境遇 紫外線下에서는 主로 p-chloro 化合物이 生成되었다. 같은 反應을 ${\gamma}$-線 照射下에서 行한 結果 에스텔과 鹽素의 몰比가 1:2일 때에는 p-chloro 化合物이 主로 生成되었으나 몰比가 1:8인 境遇에는 側鎖鹽素化物이라고 判斷되는 多鹽素化合物이 生成되었다. 反應生成物을 確認하기 爲하여서 ethyl , ${\alpha} ,{\beta} -dichloro-{\beta}$-(p-chlorophenyl) propionate 및 ethyl${\alpha} ,{\beta} -dichloro-{\beta}$ -($o$-chlorophenyl) propionate 를 各各 ${\gamma}$-線 照射下에서 鹽素化시켜 보았더니 p-chloro誘道體에서는 側鎖鹽素化物을, o-chloro誘道體에서는 o,p-dichlorophenyl 化合物에 各各 該當하는 鹽素化物을 生成하였다. 化合物 確認에는 放射化 thin layer chromatography를 利用 하였으며 鹽素含量을 放射化分析法을 分析하였다. 反應結果를 鹽素化反應에 對한 芳香族의 置換基의 效果와 關聯시켜 論議하였으며 實驗方法을 記述하였다.

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Curcumin Derivatives Inhibit the Formation of Jun-Fos-DNA Complex Independently of their Conserved Cysteine Residues

  • Park, Chi-Hoon;Lee, Ju-Hyung;Yang, Chul-Hak
    • BMB Reports
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    • 제38권4호
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    • pp.474-480
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    • 2005
  • Curcumin, a major active component of turmeric, has been identified as an inhibitor of the transcriptional activity of activator protein-1 (AP-1). Recently, it was also found that curcumin and synthetic curcumin derivatives can inhibit the binding of Jun-Fos, which are the members of the AP-1 family, to DNA. However, the mechanism of this inhibition by curcumin and its derivatives was not disclosed. Since the binding of Jun-Fos dimer to DNA can be modulated by redox control involving conserved cysteine residues, we studied whether curcumin and its derivatives inhibit Jun-Fos DNA binding activity via these residues. However, the inhibitory mechanism of curcumin and its derivatives, unlike that of other Jun-Fos inhibitors, was found to be independent of these conserved cysteine residues. In addition, we investigated whether curcumin derivatives can inhibit AP-1 transcriptional activity in vivo using a luciferase assay. We found that, among the curcumin derivatives examined, only inhibitors shown to inhibit the binding of Jun-Fos to DNA by Electrophoretic Mobility Shift Assay (EMSA) inhibited AP-1 transcriptional activity in vivo. Moreover, RT-PCR revealed that curcumin derivatives, like curcumin, downregulated c-jun mRNA in JB6 cells. These results suggest that the suppression of the formation of DNA-Jun-Fos complex is the main cause of reduced AP-1 transcriptional activity by curcuminoids, and that EMSA is a suitable tool for identifying inhibitors of transcriptional activation.

Effects of Flavonol Derivatives on the Micronudei Formation by N-methyl-N'-nitro-N-nitrosoguanidine and the Enhancement of Bleomycin-induced Chromosome Aberration by N-methyl-N'-nitro-N-nitrosoguanidine

  • Heo, Moon-Young;Kwon, Chang-Ho;Sohn, Dong-Hun;Lee, Su-Jun;Kim, Sung-Wan;Kim, Jung-Han;William W. Au
    • Archives of Pharmacal Research
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    • 제16권3호
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    • pp.196-204
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    • 1993
  • Flavonol derivatives were tested for their anticlastogenic effect against induction of micronuclei by n-methyl-n'-nitor-n-nitorsoguanidine(MNNG), and against induction of chromosome aberration by bleomycin or MNNG.belomycin. For micronudeus assay, each flavonol derivative (0, 0.001, 0.01, 0.1, 1, 10 and 100 mg/kg) was administered orally twice with 24 h interval, together with intraperitioneally administered MNNG(150 mg/kg). The result showed that msot flavonol derivatives tested were effective in suppresing the frequencies of micronude induced by MNNG. For chromosome aberration assy, each flavonol derivative (0, 0.1, 1, 10m and 100 mg/kg)was administered to mice orally in vivo, and then mice were sacrificed and spleen lymphocyte cultures were made. Bleomycin $(3\;\mu$g/ml) was treated to the mouse spleen hymphocyte cultures at 24 h after con A initiation. There wre nomarked decrease tendencies in chromosome aberration unless all doses of galangin and some doses of several flavonol derivatives tested. In the another experiment, we have evaluated the effect of flavonol derivatives on the enhancement of bleomycin-induced chromsome aberration by MNNG. Most of flavonol derivtives reduced the incidence of chromosome aberration induced by in vitro treatment of bleomycin followed by in vivo treatment of MNNG. Galangin particulary showed a dose-dependent decrease tendency. Other flavonol derivative showed slightly suggest that most of flavonol derivatives may be capable of protecting the inhibition of suggest that most of flavonol derivatives may be capable of protecting the inhibition of DNA-repair by MNNG. Our data indicate clearly that flavonol derivatives can suppress MNNG-induced genotoxicity such as an induction of MNPCEs. Therfore, our results could suggest that flavonol derivtives may be useful as a chemopreventive agent of MNNG.

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6-(1-하이드록시 또는 아실옥시알킬)-5,8-디알콕시-1,4-나프토퀴논 유도체의 합성, DNA Topoisomerase-I에 대한 억제, 세포독성 및 항암활성 (6-(1-Hydroxy or Acyloxyalkyl)-5,8-Dialkoxy-1,4-Naphthoquinones: Synthesis, Evaluation of Cytotoxic Activity; Antitumor Activity and Inhibitory effect on DNA Topoisomerase-I)

  • 김용;최수라;명평근;안병준
    • 약학회지
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    • 제44권2호
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    • pp.141-148
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    • 2000
  • A new synthetic method of 6-(1-oxyalkyl)-5,8-dimethoxy-1,4-naphthoquinones was developed, 2-formyl-1,4,5,8-tetramethoxynaphthalene was oxidized to form 6-formyl-5,8-dimethoxy-1,4-naphthoquinone(DMNQ). This was selectively reduced and benzylated to produce 6-formyl-5,8-dimethoxy-1,4-dibenzyloxynaphthalene, to which various alkylmagnesium halide were added, followed by debenzylation and oxidation in sequence, yielding 6-(1-hydroxyalkyl)-DMNQ derivatives. 6-(1-hydroxyalkyl)-5,8-diethoxy-1,4-naphthalene (DENQ) derivatives were synthesized by similar procedure. 1'-OH of the naphthoquinone derivatives was acylated with various alkanoic acids to give 6-(1-acyloxyalkyl)-DMNQ or DENQ derivatives. TOPO-I inhibitory activity and cytotoxicity of DENQs were less potent than that of DMNQs. Among the DMNQ and DENQ analogues, the ones with alkyl group being heptyl were most potent in TOPO-I inhibition $IC_{50}$/; 30.1, 36.4 $\mu$M). DUNQ derivatives with a longer side chain exhibited a weaker cytotoxicity. A correlation between size of the alkyl side chain and cytotoxicity was not observed for DENQ derivatives. Acylation of 1'-hydroxyl group, in general, decreased both TOPO-I inhibitory activity and cytotoxicity T/C (%) values of the DENQ derivatives on S-180 intraperitoneal tumor were larger than those of DMNQ derivatives. Among the compounds synthesized,6-(1-hydroxyheptyl)-DENQ and 6-(1-hex-anoyloxyoctyl)-DMNQ showed the highest T/C values of 183% and 182%, respectively.

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