• YAKHAK HOEJI
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• v.39 no.4
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• pp.417-426
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• 1995

6-[(N-4-Chlorophenyl)amino]-7-chloro-5,8-quinolinedione (RCK20) was tested for antifungal activities, in vivo, against Candida albicans. RCK20 was compared vath ketoconazole and fluconazole in the treatment of systemic infection with Candida albicans in normal rats. The therapeutic potential of RCK20 had been assessed by evaluating their activities (survival rate) against systemic infections with in normal mice with Candida albicans. RCK20 improved survival rates as well as ketokonazole. RCK20 had ED$_{50}$. 0.25$\pm$0.18 mg/kg but ketoeonazole and fluconazole had ED$_{50}$, 8.00$\pm$0.73, 10$\pm$0.43 mg/kg respectively. Activities of RCK20 showed superior to that of ketoconazole and fluconazole. Intraperitoneauy administered RCK20 at the ED$_{50}$, 0.25 mg/kg for 7days and 14days reduced Candida albicans colony count in the kidneys and livers as well as ketoconazole and fluconazole at these ED$_{50}$, 8.00 and 10 mg/kg. Acute oral toxicity studies of RCK20 were carried out in ICR mice of both sexes. These acute oral toxicities of RCK20 were low and LD$_{50}$ values were over 2.850 mg/kg in ICR mice. The Genotoxicities of RCK20 had been evaluated. RCK20 was negative in Ames test with Salmonella typhimurium (TA98 and TA100). The clastogenicity was tested on the RCK20 with in vivo mouse micronucleus assay. RCK20 did not show any clastogenic effect in mouse peripheral blood and was negative in mouse micronucleus assay. These results indicate that RCK20 has no genotoxic potential under these experimental condition.

• Applied Chemistry for Engineering
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• v.24 no.4
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• pp.402-406
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• 2013

In this study, a pitch for melt-electrospinning was prepared from naphtha cracking bottom (NCB) oil by the modification with heat treatment. The softening point and property of the modified pitch was influenced by modification conditions such as nitrogen flow rate, heat treatment temperature, and reaction time. Among these, the heat treatment temperature had a very strong influence on the distribution of molecular weight and softening point of the pitch. The C/H mole ratio and average molecular weight increased with increasing the heat treatment temperature due the decomposition and cyclization reaction of surface-functional groups. In addition, the values of benzene insoluble and quinoline insoluble also tends to decrease, and the width of molecular weight distribution seems to get more narrow. The carbon fiber with a diameter of $4.8{\mu}m$ was prepared from a modified pitch at the softening point of $155^{\circ}C$ by melt-electrospinning. It is believed that the melt-electro spinning method is much more convenient to get the thinner fiber than the conventional melt spinning method.

• YAKHAK HOEJI
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• v.54 no.6
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• pp.529-534
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• 2010

Alzheimer's disease (AD) is characterized pathologically by the presence of intracellular neurofibrillary tangles and deposition of ${\beta}$-amyloid ($A{\beta}$) peptides, which are generated by processing of amyloid precursor protein (APP). It is urgent to develop effective therapies for the treatment of AD, since our society rapidly accelerate aging. $A{\beta}$ peptides have been believed to be neurotoxic and now are also considered to have effects on the mechanism of memory formation. Recently, we investigated that a quinoline compound from natural product reduced the secretion of $A{\beta}$ from the neuroblastoma N2a cells (NL/N cell line) overexpressing APPswe. In this study, 3-phenyl-1-isoquinolinamine, a synthetic isoquinoline compound was analyzed to determine its effects on the metabolism of APP. It inhibited the secretion of $A{\beta}$ peptides from the N2a NL/N cell line. Beta-site APP cleaving enzyme (BACE) fluorescence resonance energy transfer (FRET) assay revealed that it inhibited BACE activity in a dose dependent manner. Immunoblotting study showed that it inhibited APP stabilization and expression and it slightly increased the stablization and the expression of ${\gamma}$-secreatase component from the N2a NL/N cell line. We suggest that 3-phenyl-1-isoquinolinamine inhibits APP metabolism and $A{\beta}$ generation by the means of BACE inhibitory mechanism. This is the first report that 3-phenyl-1-isoquinolinamine inhibits the secretion of $A{\beta}$ peptides from neuroblastoma cells.

• YAKHAK HOEJI
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• v.40 no.1
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• pp.90-94
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• 1996

6-[(N-4-Fluorophenyl)amino]-7-chloro-5,8-quinolinedione(RCK3) was tested for antifungal activities, in vivo, against Candida albicans. RCK3 was compared with ketoc onazole and fluconazole in the treatment of systemic infection with Candida albicans in normal mice. The therapeutic potential of RCK3 had been assessed by evaluating their activities (survival rate) against systemic infections in normal mice. RCK3 had $ED_{50},\;8.78{\pm}0.18mg/kg$ but ketoconazole and fluconazole had $ED_{50},\;8.00{\pm}0.73,\;10.00{\pm}0.43mg/kg$ respectively. Intraperitoneally administered RCK3 at the $ED_{50}$, 8.78mg/kg for 7 days and 14 days reduced Candida albicans colony count in the kidneys and livers as well as ketoconazole and fluconazole at these $ED_{50}$, 8.00 and 10.00mg/kg. And administered RCK3 at the $ED_{50}$ for 14 days improved survival rates better than ketoconazole.

• YAKHAK HOEJI
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• v.42 no.5
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• pp.527-533
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• 1998

6-(3,4-Dichlorophenyl)amino-7-chloro-5,8-quinolinedione (RCK50) was tested for antifungal activities in mice systemically infected with Candida albicans. The therapeutic potential of RCK50 was also assessed in comparison with ketoconazole. CK50 had $ED_{50}$ 0.22${\pm}$0.01mg/kg. Ketoconazole as a positive control had $ED_{50}$ 6.00${\pm}$1.70mg/kg. Intraperitoneally administered RCK50 at the $ED_{50}$ for 7 days and 14 days reduced Candida albicans colony count in the kidneys and liver. And administered RCK50 at the $ED_{50}$ for 14 days improved survival rates. The genotoxicities of RCK50 had been evaluated. RCK50 was negative in Ames test with Salmonella typhimurium and chromosomal aberration test in CHL cells. RCK50 did not show any clastogenic effect in mouse peripheral blood and was negative in mouse micronucleus assay. These results indicate that RCK50 has no genotoxic potential under these experimental conditions. Acute oral toxicity studies of RCK50 were carried out in ICR mice of both sexes. RCK50 did not show acute oral toxicities and $LD_{50}$ values were over 2,850mg/kg in ICR mice.

• Journal of the Korean Chemical Society
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• v.30 no.6
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• pp.516-520
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• 1986

This study is related to reactivity of dioxygen bridged palladium complexes having ${\pi}$-allyl ligands. In this case, new dioxygen bridged palladium complexes were prepared using superoxide ion$(O_2^-)$ as an oxygen source. Reactions of the dioxygen palladium complexes prepared in the study were examined in order to clarify the nature of the coordinated dioxygen. Treatments of a solution of the dioxygen bridged palladium complexes in benzene by water, methanol and acetic acid gave hydrogen peroxide $(H_2O_2)$ as hydroxy-, methoxy-, and acetoxybridged palladium complexes, respectively. The dioxygen bridged palladium complexes reacted also with substitution phenols of salicylaldehyde, 8-hydroxyquinoline and active methylenes of acetylacetone, dimethyl malonate to afford mononuclear complexes of palladium and hydrogen peroxide. The results suggest that dioxygen is coordinated as peroxo $(O_2^{2-})$ in the complexes and behaves as a strong base.

• Applied Chemistry for Engineering
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• v.3 no.3
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• pp.471-481
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• 1992

This study is related to the reactivity of dioxygen bridged palladium complexes having amine ligands. New dloxygen bridged palladium complexes were prepared using superoxide ion(${O_2}^-$) as an oxygen source. The reactions of dioxygen palladium complexes prepared in the study were examined in order to clarify the nature of the coordinated dioxygen. Treatments of a solution of the dioxygen bridged palladium complexes in benzene by water, methanol, acetic acid gave hydrogen peroxide($H_2O_2$) and hydroxy, methoxy, acetoxy-bridged palladium complexes, respectively. The dioxygen bridged palladium complexes reacted with substitution phenols of salicylaldehyde, 8-hydroxyquinoline and active mothylenes of acetylacetone, dimethyl malonate to afford mononuclear complexes of palladium and hydrogen peroxide. Furthermore, she dioxygen bridged palladium complexes changed to acetonyl bridged palladium complex and hydrogen peroxide reacting with acetone. The results suggest that dioxygen is coordinated as peroxo (${O_2}^{2-}$) in the complexes and behaves as a strong base.

• Clean Technology
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• v.16 no.3
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• pp.206-212
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• 2010

The adsorption characteristics of quinoline yellow by granular activated carbon were investigated experimently in the batch adsorber and packed column. The adsorptivity of activated carbon for quinoline yellow were largely improved by acidic pH and higher temperature. When the pH was 3 at $60^{\circ}C$, quinoline yellowcould be removed 97 percent of initial concentration(10 mg/L). It was estabilished that the adsorption equilibrium of quinoline yellow on granular activated carbon was successfully fitted by Freundlich isotherm equation in the temperature range from $25^{\circ}C$ to $60^{\circ}C$. The estimated values of k and ${\beta}$ are 38.71~166.60, 0.380~0.490, respectively. The breakthrough curve of activated carbon-packed column depends on the design variables such as initial concentration, bed height, and flow rate.

• Analytical Science and Technology
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• v.6 no.1
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• pp.29-37
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• 1993

Some new podands containing phenyl(B), benzyl(Bz), pyridine(Py), quinoline(Q) and naphthalene(Np) as end-groups, and oxygen(O) and sulfur(S) in ether chains as donor atoms have been synthesized. The univalent cation binding characteristics of these podands have been studied by NMR titration and solvent extraction. By NMR titration we have found that the most of podands form 1:1 complexes with $Ag^+$ ion. Especially, the substituted sulfur atoms in ether chains show the effects to enhance the stabilities. We also carried out the extractions of univalent cation picrates including alkaline metal, $Ag^+$, $Tl^+$ and $NH_4{^-}$ ions from aqueous to chloroform layer by using these podands. We found that the extractabilities of $Ag^+$ ion with the quinoline-containing podands such as, $Q_2O_4$, $Q_2O_5$ and $BQO_5$ were 86.8, 86.6 and 48.0% respectively, but the naphthalene-containing podands such as, $Np_2O_4$ and $Np_2O_5$ extracted quite small amount. Otherwise, in cases of $Bz_2O_3S_2$(89.4%), $B_2O_2S_2$(96.8%), $B_2O_3S_2$(58.9%), $Py_2O_2S_2$(58.8%), $Py_2O_3S_2$(42.1%), and $B_2O_4S$(15.0%), interestingly, $Bz_2O_3S_2$ which have sulfur atoms and benzyl groups showed the highest extraction selectivity for $Ag^+$ ion. This result seems due to not only the strong interaction of $Ag^+$ ion with sulfur donors according to the HSAB theory, but also the effective ${\pi}-{\pi}$ stacking interaction between two aromatic end-groups which is enhanced by the flexible methylene spacing group in benzyl groups instead of phenyl groups. The extraction coefficients gave the similar tendency as the extractabilities and the stabilities. From these results, it could be concluded that the predominant factor affected to extraction coefficients is the stabilities, which are strongly influenced by the structures of podands.

• Korean Chemical Engineering Research
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• v.43 no.6
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• pp.745-750
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• 2005

Naphtha cracking bottoms(NCB) oil was reformed by varying the heat treatment temperature, treatment time, and nitrogen flow rate in preparation of precursor pitch for isotropic pitch-based carbon fibers and activated carbon fibers. The reformed pitches were investigated in the yield, softening point, elementary analysis, and molecular weight distribution, and then the precursors reformed were melt spun to certify the optimum reforming conditions. The optimum precursor pitch was prepared when the NCB oil was reformed at $380^{\circ}C$, 3 h and 1.25 vvm $N_2$, and it's the softening point was around $240^{\circ}C$. The reforming resulted in product yield of 21 wt％. The C/H mole ratio of the precursor pitch increased from 1.07 to 1.34, the aromaticity increased from 0.85 to 0.88. The insolubles in benzene and quinoline were 30.0 wt％ and 1.5 wt％, respectively. The spinning temperature was about $50^{\circ}C$ higher than the softening point. The molecular weights of the precursor components were distributed from 250 to 1250, and 80％ of them were in the range of 250 to 700.