• Bulletin of the Korean Chemical Society
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• v.32 no.4
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• pp.1249-1252
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• 2011

Inhibition of BACE 1 activity is considered as a promising therapeutic target for Alzheimer's Disease (AD). Synthesis and inhibitory activities of (4-arylpiperazinyl)piperidines by bioisosteric replacement of a biaryl group with an arylpiperazine as BACE 1 inhibitors are described. The resulting (4-arylpiperazinyl)piperidines represent novel nonpeptide BACE 1 inhibitors with improved in vitro potency.

• Bulletin of the Korean Chemical Society
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• v.23 no.4
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• pp.593-597
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• 2002

(R,S)- and (R)-2-Benzylcysteine (1) and (R,S)-2-phenethylcysteine (2) were synthesized and evaluated as inhibitors for carboxypeptidase A (CPA) with the expectation that these compounds exhibit improved inhibitory activities over 2-benzyl-3-mercaptopropanoic acid (BMPA), a potent CPA competitive inhibitor, possibly having additional interactions of their amino group with the carboxylate of Glu-270 of the enzyme upon binding to CPA. Contrary to the expectation, however, the CPA inhibitory potencies of these compounds were found to be much reduced compared with that of BMPA, suggesting that the amino group in the inhibitors rather exerts steric hindrance in binding of these inhibitors to CPA.

• Bulletin of the Korean Chemical Society
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• v.18 no.10
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• pp.1100-1104
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• 1997

Compounds containing a nitrone moiety were designed, synthesized and evaluated as a new type of active site zinc ligating substrate analog inhibitors for carboxypeptidase A. The kinetic results indicated that they are competitive inhibitors for the enzyme, supporting the design rationale that the oxygen of the nitrone forms a coordinative bond to the active site zinc ion. The present study demonstrates that nitrone is useful as a zinc coordinating ligand in the design of inhibitors for zinc containing proteolytic enzymes.

• Bulletin of the Korean Chemical Society
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• v.23 no.3
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• pp.515-517
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• 2002

• Bulletin of the Korean Chemical Society
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• v.3 no.3
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• pp.122-129
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• 1982

In order to extend our understanding on the multiple inhibition enzyme kinetics, a general equation of an enzyme reaction in the presence of two different reversible inhibitors was derived by what we call "match-box mechanism" under the combined assumption of steady-state and quasi-equilibrium for inhibitor binding. Graphical methods were proposed to analyze the multiple inhibition of an enzyme by any given sets of different inhibitors, i.e., competitive, noncompetitive, and uncompetitive inhibitors. This method not only gives an interaction factor $({\alpha})$ between two inhibitors, but also discerns ${\alpha}_1$ and ${\alpha}_2$ with and without substrate binding, respectively. The factors involved in the dissociation constants of inhibitors can also be evaluated by the present plot. It is also shown that the present kinetic approach can be extended to other forms of activators or hydrogen ions with some modification.

• Bulletin of the Korean Chemical Society
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• v.21 no.11
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• pp.1085-1089
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• 2000

The effect of 2-hydroxyacetophenone-aroyl hydrazone derivatives on the inhibition of copper corrosion in 3N nitric acid solution at 303 K was investigated by galvanostatic polarization and thermometric techniques. A significant decrease in the cor rosion rate of copper was observed in the presence of the investigated compounds. The corrosion rate was found to depend on the nature and concentrations of the inhibitors. The degree of surface coverage of the adsorbed inhibitors is determined from polarization measurements, and it was found that the results obey the Frumkin adsorption isotherm. The inhibitors acted as mixed-type inhibitors, but the cathode is more polarized. The relative inhibitive efficiency of these compounds has been explained on the basis of structure dependent electron donor properties of the inhibitors and the nature of the metal-inhibitor interaction at the surface. Also, some thermodynamic data for the adsorption process ( ΔGa* and f ) are calculated and discussed.

• Bulletin of the Korean Chemical Society
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• v.23 no.3
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• pp.454-458
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• 2002

Furo[3,2-h]quinoline derivatives were synthesized as a gastric $H^+$/$K^+$-ATPase inhibitors. The oxycyclization of 7 and 8-positions in quinoline potentiated the inhibitory activity, while no significant changes in biological activity were observed by the variation of substituents in furan ring. The several furo[3,2-h]quinoline derivatives were worthy of in vivo investigation for their anti-secretory and anti-ulcer activity.

• Bulletin of the Korean Chemical Society
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• v.16 no.5
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• pp.454-458
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• 1995

Inhibiting action of semicarbazide, thiosemicarbazide, sym. diphenylcarbazide towards corrosion of zinc in hydrochloric acid has been investigated. The rate of corrosion depends on the nature of the inhibitor and its concentration. The values of inhibition efficiency from, weight loss, thermometric measurements are in good agreement with those obtained from polarization studies. From the polarization studies, the inhibitors used act as mixed absorption type inhibitors, increased adsorption resulting from an increase in the electron density at the reactive C=S and C=O groups and N-atoms. The thermodynamic parameters of adsorption obtained using Bockris-Swinkels adsorption isotherm reveal a strong interaction of these carbazides on zinc surface.

• Bulletin of the Korean Chemical Society
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• v.10 no.6
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• pp.564-567
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• 1989

The use of some mono-substituted phenyl N-phenylcarbamates derivatives as corrosion inhibitors for nickel in 1M perchloric acid was studied by galvanostatic polarization. The inhibition appears to function through general adsorption isotherm. However, galvanostatic polarization data suggest that in the case of all seven inhibitors both anode are polarized under the influence of an external current. Electrocapillary measurements have also revealed that the tendency of the inhibitors tested to adsorb on metallic surface follows the same order of efficiency.

• Bulletin of the Korean Chemical Society
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• v.34 no.7
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• pp.2006-2010
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• 2013

Leukocyte common antigen-related phosphatase (LAR) has been considered a promising target for the development of therapeutics for neurological diseases. Here, we report the first example for a successful application of the structure-based virtual screening to identify the novel small-molecule LAR inhibitors. Five of these inhibitors revealed micromolar inhibitory activities with the associated $IC_{50}$ values ranging from 2 to 6 ${\mu}M$. Because the newly identified inhibitors were also screened for having desirable physicochemical properties as a drug candidate, they may serve as a starting point of the structure-activity relationship study to optimize the medical efficacy. Structural features relevant to the stabilization of the new inhibitors in the active site of LAR are discussed in detail.