• Title/Summary/Keyword: Acylation

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Acylation of Wool Keratin with Dibasic Acid Anhydrides - on reaction mechanism - (2염기산 무수물에 의한 양모섬유의 아실화(I) - 반응메카니즘을 중심으로 -)

  • 신은주;박찬헌;최석철
    • Textile Coloration and Finishing
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    • v.7 no.1
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    • pp.65-71
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    • 1995
  • Wool yarns were treated in dimethylformamide solutions containing various concentrations of three dibasic acid anhydrides : succinic, itaconic, and phthalic anhydrides in various conditions. The structural aspects of these dibasic acid anhydrides are different : the succinic, itaconic, and phthalic acid anhydrides have saturated aliphatic etylene, unsaturated aliphatic vinyl and aromatic phenyl groups, respectively. The reaction mechanism of the acylation of wool keratin and some resction conditions were invastigated. And the results are as follows. 1. The N-acylation and formation of free carboxyl group were dominant rather than the O-acylation cross-linked on the side chain of polypeptide. The acylation of wool keratin is easier than that of silk fibroin. 2. The higher molecular weight, steric hinderance and resonance caused lower acylating reactivity. By the determination of acyl contents for acylated keratin, it was rerealed that the degree of acylation was succinic acid anhydride > itaconic acid anhhydride > phthalic acid anhydride.

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TMEDA: Efficient and Mild Catalyst for the Acylation of Alcohols, Phenols and Thiols under Solvent-free Condition

  • Kadam, Santosh T.;Lee, Han-Bin;Kim, Sung-Soo
    • Bulletin of the Korean Chemical Society
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    • v.30 no.5
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    • pp.1071-1076
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    • 2009
  • N,N,N′,N′-tetramethylethylenediamine (TMEDA) acts as a simple, mild and efficient catalyst for the acylation of alcohols, phenols and thiols at room temperature under solvent-free condition. Acylation reaction with acetic anhydride and benzoic anhydride proceeds with good to excellent yield in the presence of TMEDA as the catalyst.

Effect of Acylation on the Structure of the Acyl Carrier Protein P

  • Hyun, Ja-shil;Park, Sung Jean
    • Journal of the Korean Magnetic Resonance Society
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    • v.19 no.3
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    • pp.149-155
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    • 2015
  • Acyl carrier protein is related with fatty acid biosynthesis in which specific enzymes are involved. Especially, acyl carrier protein (ACP) is the key component in the growing of fatty acid chain. ACP is the small, very acidic protein that covalently binds various intermediates of fatty acyl chain. Acylation of ACP is mediated by holo-acyl carrier protein synthase (ACPS), which transfers the 4'PP-moiety of CoA to the 36th residue Ser of apo ACP. Acyl carrier protein P (ACPP) is one of ACPs from Helicobacter plyori. The NMR structure of ACPP consists of four helices, which were reported previously. Here we show how acylation of ACPP can affect the overall structure of ACPP and figured out the contact surface of ACPP to acyl chain attached during expression of ACPP in E. coli. Based on the chemical shift perturbation data, the acylation of ACCP seems to affect the conformation of the long loop connecting helix I and helix II as well as the second short loop connecting helix II and helix III. The significant chemical shift change of Ile 54 upon acylation supports the contact of acyl chain and the second loop.

A Study of the Competitive Reaction of C-Acylation Versus O-Acylation on the 3,4-Dichloroacetophenone (3,4-디클로로아세토페논에 대한 C-아실화와 O-아실화의 경쟁적 반응에 관한 연구)

  • You Seung Kim;He Duck Mah;Hyoung Sug Kim
    • Journal of the Korean Chemical Society
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    • v.35 no.5
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    • pp.580-585
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    • 1991
  • Quinolone derivatives have been used as antibacterial agents. In this work, the competitive C-and O-acylation reaction of 3,4-dichloroacetophenone, as a model study for the synthesis of quinolone intermediate, is studied. The effects of various bases, solvents and the leaving groups of acylating agents on the ratio of C-versus O-acylation of 3,4-dichloroacetophenone are elucidated by means of employing ethylchloroformate, ethylphenylcarbonate and diethylcarbonate as acylating agents. In aprotic solvents, C-acylation reactions occur more predominantly as the size of metal ions composing bases becomes smaller. Regarding the effects of leaving groups, it is shown that C-acylation product is increased as the ability of leaving groups of acylating agents decreases. The ratio of C/O-acylation is also observed to be increased as the polarity of solvents decreases.

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Properties of Acylated Mungbean Whole Globulin (Acyl화에 의한 녹두 Whole Globulin의 특성에 관한 연구)

  • Kim, Yong-Hwan;Song, Jong-Seon;Kim, Gwang-Su
    • The Korean Journal of Food And Nutrition
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    • v.2 no.1
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    • pp.18-26
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    • 1989
  • The objective of this study was to improved the limited functional characteristics of mungbean whole globulin. The mungbean whole globulin was acylated with succinic and acetic anhydride, and the functional properties of acylated protein were investigated, The results obtained ware as follows. 1. The UV-absorption spectra of acylated whole globulins with that of the succinylated 74% whole globulin as large blue shift of the absorption maximum and minimum wavelength from 275 nm to 269 nm, respectively. 2. The mobility of acylated whole globulin were increased on PAGE pattern, and degree of mobility was particularly remarkable in case of succinylation, 3. The water absorption capacity of whole globulin was increased by acylation. The most increased rate of whole globulin was 174,02% from succinylated 74%. The oil absorption capacity of whole globulin was increased by acylation The most increased rate of whole globulin was 165.41% from acetylated 81.77%. 4. The bulk density of whole globulin was decreased by acylation. and the greater the extent of acylation, the smaller the bulk density. 5. The foaming capacity and stability of whole globulin was increased by acylation, and remarkably high in 74% succinylated whole globulin. In contrast, however, the foaming capacity and stability of native and acylated whole globulin were decreased by heat treatment.

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Polystyrene Supported Al(OTf)3: an Environmentally Friendly Heterogeneous Catalyst for Friedel-Crafts Acylation of Aromatic Compounds

  • Boroujeni, Kaveh Parvanak
    • Bulletin of the Korean Chemical Society
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    • v.31 no.11
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    • pp.3156-3158
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    • 2010
  • Stable and non-hygroscopic polystyrene supported aluminium triflate (Ps-$Al(OTf)_3$), which is prepared easily from cheap and commercially available compounds was found to be an environmentally friendly heterogeneous catalyst for Friedel-Crafts acylation of arenes using acid chlorides in the absence of solvent under mild reaction conditions. The catalyst can be reused up to five times after simple washing with dichloromethane.

Post-Translational Modification of Proteins in Toxicological Research: Focus on Lysine Acylation

  • Lee, Sangkyu
    • Toxicological Research
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    • v.29 no.2
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    • pp.81-86
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    • 2013
  • Toxicoproteomics integrates the proteomic knowledge into toxicology by enabling protein quantification in biofluids and tissues, thus taking toxicological research to the next level. Post-translational modification (PTM) alters the three-dimensional (3D) structure of proteins by covalently binding small molecules to them and therefore represents a major protein function diversification mechanism. Because of the crucial roles PTM plays in biological systems, the identification of novel PTMs and study of the role of PTMs are gaining much attention in proteomics research. Of the 300 known PTMs, protein acylation, including lysine formylation, acetylation, propionylation, butyrylation, malonylation, succinylation, and crotonylation, regulates the crucial functions of many eukaryotic proteins involved in cellular metabolism, cell cycle, aging, growth, angiogenesis, and cancer. Here, I reviewed recent studies regarding novel types of lysine acylation, their biological functions, and their applicationsin toxicoproteomics research.