• Title/Summary/Keyword: Methyl

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Stereospecific Synthesis of Methyl-6-deoxy-$\beta$-L-idopyranoside (Methyl-6-deoxy-$\beta$-L-idopyranoside의 합성)

  • 민신홍;박복구;옥광대
    • YAKHAK HOEJI
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    • v.30 no.6
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    • pp.352-355
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    • 1986
  • Methyl-6-deoxy-$\beta$-L-idopyranoside was prepared in good yield by treatment of methyl 2,3,4-tri-O-benzyl-6-deoxy-$\alpha$-D-xylo-hex-5-enopyranoside with H$_2$ on pd, followed by reaction of Na/NH$_3$ at $-50^{\circ}C$. The ratio of L-idopyranoside and D-glucopyranoside was 7 to 1 in 80.7%. It was confirmed that L-idopyranoside was 1C conformation as being expected.

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Synthesis of 2-(2-Fluorenyl)propanoic Acid

  • Choi, Hong-Dae;Geum, Dek-Hyun;Kowak, Young-Sil;Son, Byeng-Wha
    • Archives of Pharmacal Research
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    • v.17 no.1
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    • pp.17-20
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    • 1994
  • Friedel-Crafts reaction of fluorene with methyl ${\alpha}$-chloro-${\alpha}$-(methylthio)acetate 1 gave methyl $\alpha$-methylthio-2-fluoreneacetate 2. Cicloprofen 8, a potent antiinflammatory agent, was prepared by methylation of 2 followed by reductive desulfurization of methyl 2(2-fluorenyl)-2-(methylthio)propionate 6 and hydrolysis of methyl 2-(2-fluorenyl)propionate 7.

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Steroidal Saponins from the Rhizomes of Smilax china

  • Kim, Sung-Whan;Chung, Kyu-Charn;Son, Kun-Ho;Kang, Sam-Sik
    • Korean Journal of Pharmacognosy
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    • v.20 no.2
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    • pp.76-82
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    • 1989
  • Five known diosgenin glycosides have been isolated from the MeOH extract of Smilax china rhizomes and characterized as prosapogenin A of dioscin, dioscin, gracillin, methyl protogracillin, methyl protodioscin and its corresponding 22-hydroxy analog. This is the first isolation of the former four compounds from this plant. ${\beta}-Sitosterol\;glucoside$ was also isolated and identified.

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Synthesis and Reaction of Novel Tricyclic Dynemicin A Models with Methyl Group

  • 류훈한;홍용표
    • Bulletin of the Korean Chemical Society
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    • v.17 no.9
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    • pp.831-835
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    • 1996
  • New dynemicin A mimics with methyl group 2a and 2b were synthesized, and acid-induced hydrolyzed to see an electronic effect of substituent for epoxide opening. The model 2a with methyl group at C3 position was more rapidly transformed to diol 16a than 2b with methyl group at C2. This result suggests that any substituent at C3 position plays more important role than any substituent at C2 position in the dynemicin A mimic activation.

A Study on the Removal Efficiency of a TEDA Impregnated Charcoal Bed for Methyl iodide under Humid Conditions (습윤 조건하에서 TEDA함침탄소층에 의한 Methyl Iodide 제거효율에 관한 연구)

  • Won Jin Cho;Soon Heung Chang
    • Nuclear Engineering and Technology
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    • v.16 no.3
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    • pp.161-168
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    • 1984
  • The adsorption model to predict the time dependent removal efficiency of methyl iodide by triethylenediamine (TEDA) impregnated charcoal bed under humid condition is proposed. Under humid conditions, the reduction of equilibrium adsorption capacity and effective pore diffusivity is considered. The predicted values are compared with the experimental results.

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cis-trans Isomeric and Substituent Effects on the Lanthanide Induced Shifts in 2-Phenylcyclopropanic System

  • So, Jung-Ho;Cho, Nam-Sook
    • Bulletin of the Korean Chemical Society
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    • v.5 no.6
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    • pp.226-230
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    • 1984
  • LIS's of cis and trans-methyl-2-phenylcyclopropanecarboxylate, cis and trans-t-butyl-2-phenylcyclopropanecarboxylate, cis and trans-N,N-dimethylcyclopropanecarboxamide, trans-2-phenylcyclopropyl methyl ketone and trans-2-phenylcyclopropyl t-butyl ketone have been studied. The LIS's hold the McConnell-Robertson relation and are mainly influenced by the steric effect. LIS's of trans isomers are larger than those of cis isomers. In trans isomers, the LIS's decrease in the following order: methyl ketone > methyl ester > N,N-dimethyl amide > t-butyl ketone${\sim}$t-butyl ester.

Designing of Antiepileptic Ligands by Esterification and Acetylation of Dipeptides

  • Vishwakarma, K.K.;Saraf, S.K.;Uppadhyay, R.K.;Kohli, D.V.
    • Archives of Pharmacal Research
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    • v.15 no.3
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    • pp.204-207
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    • 1992
  • Glycylglycine, alanylalanine and alanylglycine were synthesized, their free carboxylic and amino groups were converted to methyl esters of N-acetylglycyglycine, N-acetylalanylglycine and N-acetylalanylalanine. The synthesized compounds were evaluated for antiepileptic activity, plasmaprotein binding, $TD_{50}$ and potentiating effect of phenobarbitone sodium.

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Protective Effect of Iminoctadine tris(albesilate) and Kresoxim-methyl Fungicides to Citrus Postharvest Diseases caused by Penicillium spp. (저장 감귤의 부패에 관여하는 Penicillium spp.에 대한 Iminoctadine tris(albesilate)와 Kresoxym-methyl의 방제 효과)

  • Hyun, Jae-Wook;Lee, Seong-Chan;Ihm, Yang-Bin;Kim, Dong-Hwan;Ko, Sang-Wook;Kim, Kwang-Sik
    • The Korean Journal of Pesticide Science
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    • v.5 no.2
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    • pp.37-44
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    • 2001
  • The biological effects of the iminoctadine tris (albesilate) and kresoxim-methyl for the protection of citrus postharvest diseases caused by penicillium spp. were assayed. In vitro tests, $EC_{50}$ values of iminoctadine tris(albesilate) were $0.01{\sim}0.02\;and\;0.01{\mu}g$ a.i./mL against mycelial growth of P. italicum and P. digitatum, respectively, but iminoctadine tris(albesilate) at $0.64{\mu}g$ a.i. /mL inhibited a little mycelial growth of unknown Penicillium sp. which produced another symptom different to blue and green mold caused by P. italicum and P. digitatum, respectively. And against germination and growth of germ tube of P. italicum and P. digitatum, $EC_{50}$ value of iminoctadine tris(albesilate) was $0.0013{\sim}0.0025{\mu}g$ a.i./mL. But spore germination of unknown Penicillium spp. was not nearly inhibited at $0.2{\mu}g$ a.i./mL. $EC_{50}$ values of kresoxim-methyl were $0.08{\sim}0.16$, 0.04 and $0.16{\mu}g$ a.i./mL against mycelial growth of P. italicum, P. digitatum and unknown Penicillium sp., respectively, and $0.04{\sim}0.08{\mu}g$ a.i./mL and $0.01{\sim}0.02{\mu}g$ a.i./mL against germination and growth of germ tube of P. italicum and unknown Penicillium sp., and P. digitatum, respectively. Iminoctadine tris(albesilate) and kresoxim-methyl were markedly effective to control the postharvest disease by 7 days spray prior to harvest. When the fruits were sprayed with iminoctadine-tris(albesilate) ($200{\mu}g$ a.i./mL) and kresoxim-methyl ($155{\mu}g$ a.i./mL) 7 days prior to harvest and subsequently stored for 90 days, the percentage of diseased fruit by Penicillium spp. was $3.6{\pm}1.8%$ in treatment of kresoxim-methyl and $5.9{\pm}1.8%$ in iminoctadine-tris(albesilate), respectively. On the other hand, tile percentage of diseased fruit was relatively high, $20.3{\pm}10.0%\;and\;19.5{\pm}9.6%$ in thiophanate-methyl ($700{\mu}g$ a.i./mL) and non-treatment, respectively. Maximum residue amount (ppm) among fruits (flesh and peel) assayed 0, 30, 60 and 90 days after storage was 0.45 and 0.10 ppm in treatment of kresoxim-methyl and iminoctadine, respectively.

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