• Title/Summary/Keyword: Malonate

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Synthesis of Heterocyclic Quinones Containing Bridgehead Nitrogen Atom from 2-Aminonaphtho[2,3-d]thiazole-4,9-dione

  • Fandy, Ragab F.
    • Archives of Pharmacal Research
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    • v.23 no.5
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    • pp.446-449
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    • 2000
  • Imidazonaphthothiazole derivatives 3∼6 were prepared by treatment of 2-aminonaphtho[2,3-d]-thiazole-4,9-dione(1) with phenacyl bromide, chloroacetic acid, diethyl oxalate and 2,3-dichloroquinoxaline respectively. The reaction of 1 with ethyl acrylate, ethyl acetoacetate and diethyl malonate gave the corresponding naphthothiazolopyrimidine derivatives 8∼11.

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Surface Properties and the Catalytic Activity of Amorphous Iron Aluminophosphates: Effect of Fe Loading (비정질 인산알루미늄 철의 표면 성질 및 촉매 특성: 함유된 철의 양에 의한 효과)

  • Vijayasankar, A.V.;Aniz, C.U.;Nagaraju, N.
    • Journal of the Korean Chemical Society
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    • v.54 no.1
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    • pp.131-136
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    • 2010
  • Iron aluminophosphates (FeAlP) with different percentage of iron were synthesized and characterized for their surface and bulk properties. The catalytic activity was determined in the transesterification of diethyl malonate with benzyl alcohol. Benzyl ethylmalonate and dibenzyl malonate were obtained as the only products. FeAlP with 0.025 mole % of iron was found to be distinctly different in its textural and catalytic properties. Formation of diester was found to be favored by the acid sites of intermediate strength. The presence of hydrated alumina and the polycondensed phosphates in the materials reduced the catalytic activity of iron aluminophosphates in transesterification reaction.

Determination of the Solution Structure of Malonyl-CoA by Two-Dimensional Nuclear Magnetic Resonance Spectroscopy and Dynamical Simulated Annealing Calculations

  • Jung, Jin-Won;An, Jae-Hyung;Kim, Yu-Sam;Bang, Eun-Jung;Lee, Weon-Tae
    • BMB Reports
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    • v.32 no.3
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    • pp.288-293
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    • 1999
  • In order to understand the initial interaction of the substrates malonate, ATP, and CoA with malonyl-CoA synthetase, the catalytic product malonyl-CoA was characterized by NMR spectroscopy and molecular modeling. To assign proton and carbon chemical shifts, two-dimensional $^1H-^1H$ DQF-COSY and $^1H-^{13}C$ HMBC experiments were used. The structure of malonyl-CoA in the solution phase was determined based on distance constraints from NOESY and ROESY spectra. The structures were well-converged around the pantetheine region with the pairwise RMSD value of 0.08 nm. The solution structure exhibited a compact folded conformation with intramolecular hydrogen bonds among its carbonyl and hydroxyl groups. These findings will help us to understand the initial interaction of malonate and CoA with malonyl-CoA synthetase.

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Biochemical characterization of Bacillus thuringiensis, 23 serovars (Biochemical thuringiensis, 23 serovars의 생화학적 특성)

  • Lee, Hyung-Hoan;Park, Mi-Yeoun;Lee, Chang-Woon
    • Microbiology and Biotechnology Letters
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    • v.14 no.2
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    • pp.205-208
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    • 1986
  • The 23 serovars of Bacillus thuringiensis strain were commonly gram-positive and motile, formed endotoxin crystals, produced acid and alkali in the KIA media, and acid from glucose, hydrolyzed starch, and reduced nitrate but did not produce H$_2$S, oxidase and indole, did not decompose lysine, ornithine, phenylalanine, malonate, lactose, dulcitol, adonitol, inositol, sorbitol, arabinose, raffinose, rhamnose, maltose, and xylose. Eighteen serovars were positive in the MR tests and 15 in the VP tests. Four serovars used citrate. Five serovars produced urease, 5 $CO_2$ from glucose, 2 DNase, and 15 lecithinase. Twelve serovars decomposed arginine, 11 did sucrose, 2 manitol, and 9 salicin Serovar tohokuensis did not hemolyze, but the others did.

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Complexes of Manganese, Cobalt and Zinc with Dibasic Organic Acids in Aqueous, Ethanol-Water and Acetone-Water Solutions (망간, 코발트 및 아연과 2 염기 유기산 사이의 착물)

  • Sang Up Choi;Dong Jae Lee
    • Journal of the Korean Chemical Society
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    • v.18 no.1
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    • pp.31-39
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    • 1974
  • Solutions of $Mn^{++}, Co^{++} and Zn^{++}$ were mixed with various dibasic organic acids in the presence of cation exchange resin at room temperature. The distribution ratios of the metal ions between resin and solution were measured, using radioactive metal ions as tracer. From the observed variation of the distribution ratios with acid anion concentrations, it was concluded that $Mn^{++}, Co^{++}$ and $Zn^{++}$ formed one-to-one complexes with succinate, malonate, o-phthalate and tartrate ions in aqueous, 20 % ethanol-water and 20 % acetone-water solutions. The results of the present investigation indicated that the relative stabilities of the complexes increased in the order: $Mn^{++} < Co^{++} < Zn^{++} complexes, Succinate < malonate < o-phthalate < tartrate complexes, Aqueous < mixed solvent systems.$

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Analysis of Kerr and thermal nonlinearities in unsatuared polymers with a nanosecond laser

  • Kim, Sang-Cheon;Choi, Moon-Goo;Park, Seung-Han;Kim, Hwan-Kyu;Lee, Ji-Hoon
    • Journal of the Optical Society of Korea
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    • v.3 no.2
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    • pp.47-50
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    • 1999
  • Nonlinear optical properties of an unsaturated polymer (poly trifluroethy dipropargy malonate) are investigated by using a passive Q-switched Nd:YAG laser. Double-peaked structure of phase conjugate signals due to the two-photon-absorption induced thermal effect is clearly is clearly observed and a simple method to remove the thermal effect from the overall phase-conjugate signals is demonstrated.

Generation of Hybrid Polyketides through Combinatorial Biosynthesis of Polyketide Synthase (PKS) and Modification of Post-PKS Tailoring Steps

  • Yoon, Yeo-Joon
    • Proceedings of the PSK Conference
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    • 2003.10a
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    • pp.75-78
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    • 2003
  • Polyketides are a class of structurally diverse natural products which possess a wide range of biological activities. These compounds are used throughout medicine and agriculture as antimicrobials, immunosuppressants, antiparasitics, and anticancer agents. While structurally diverse, polyketides are assembled by a common mechanism of decarboxylative condensations of simple malonate derivatives by polyketide synthases (PKSs) in a manner very similar to fatty acid biosynthesis (Fig 1). (omitted)

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Kinetic Studies on the Oxidation Reaction of Malonic Acid by Ceric Ion (세륨(Ⅳ)에 의한 말론산의 산화반응에 관한 반응속도론적 연구)

  • Kim, Wang Gi
    • Journal of the Korean Chemical Society
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    • v.38 no.10
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    • pp.705-709
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    • 1994
  • The kinetics of the oxidation reaction of malonic acid by ceric ion in 1 M sulfuric acid solution at $20^{\circ}C$ have been investigated by spectrophotometric method. The reaction rate at a large excess of malonic acid was found to be pseudo-first order. The observed pseudo-first order rate constants, $k_{obs}$, are dependent on the concentration of malonic acid, [MA], of which relationship has been found to be $k_{obs}$ = (0.592[MA])/(1+14.5[MA]$^2$). A mechanism for the reaction has been suggested on the basis of the above rate equation. The rate determining step may be the electron transfer reaction between enolate type malonate anion, which is formed by the acid dissociation reaction of malonic acid, and Ce(IV). The rate depression in the range of high concentration of MA has been explained by the formation of 1 : 2 chelate between Ce(IV) and malonate. According to the mechanism, the pH dependence of the rate, which was studied by Sengupta et al., has also been explained.

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