• Journal of the Korean Chemical Society
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• v.55 no.6
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• pp.969-973
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• 2011

The synthesis, as well as spectroscopic and biological studies of a novel class of [3-(4-substitutedphenylamino)-8-azabicyclo [3.2.1] oct-8yl]-phenyl-methanone derivatives are described. All the synthesized compounds were characterized by elemental analysis FTIR, $^1H$-NMR, $^{13}C$ NMR, and Mass spectral data. All the synthesized compounds were exhibit in vitro antibacterial activity.

• Bulletin of the Korean Chemical Society
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• v.33 no.12
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• pp.4103-4108
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• 2012

Efficient double click methods for the synthesis of diblock codendrimers were developed. The synthetic strategy involved the sequential click reactions between an alkyne and an azide. The short core building block, 1,4-diazidobutane, was chosen to serve as the azide functionalities for dendrimer growth via click reactions with the alkyne-functionalized PAMAM dendrons as hydrophilic dendron and alkyne-functionalized Fr$\acute{e}$chet-type dendrons as hydrophobic dendron. The structure of diblock codendrimers was confirmed by $^1H$ and $^{13}C$ NMR spectroscopy, IR spectroscopy, mass spectrometry, and GPC analysis.

• Journal of the Korean Chemical Society
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• v.47 no.1
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• pp.47-58
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• 2003

Fibrosstatins, which were isolated from the culture broth of Streptomyces catanulae subsp. griseospora, are naphthoquinones which can work as alkylating agents. It is important to synthesize these quinone compounds for the study of their biological activities. In this paper, an efficient method, Hooker oxidation, to control the regiochemistry in the synthesis of fibrostatin B is reported.

• YAKHAK HOEJI
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• v.49 no.1
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• pp.56-59
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• 2005

We synthesized new N-substituted 3-amino-6-chloropyridazine derivatives which were expected to retain biological activity. All synthetic process from pyridazine to 3-aminopyridazines could be carried out conveniently in high yield. N-Substituted 3-amino-6-chloropyridazine derivatives were prepared through amination and acylation from 3,6-dichloropyridazine. 3-Amino-6-chloropyridazine was prepared from the reaction of 3,6-dichloropyridazine with liquid ammonia under autoclave for 6 hrs. The refluxing of 3-amino-6-chloropyridazine and the corresponding acid anhydride for $1{\sim}2$ hrs afforded the N-substituted 3-amino-6-chloropyridazines. Alkyl chain of N-substituent was prolonged to six carbon (hexanoic acid).

• Archives of Pharmacal Research
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• v.29 no.6
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• pp.469-475
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• 2006

A series of yakuchinone B 1f and its analogs 1a-e was synthesized and evaluated for free radical scavenging, suppression of LPS-induced NO generation, cytotoxicity and anti-excitotoxicity in vitro. Compound 1c exhibited potent anti-excitotoxicity, while all compounds 1a-f showed considerable effects of free radical scavenging, suppression of LPS-induced NO generation, and cytotoxicity in microglia.

• Archives of Pharmacal Research
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• v.26 no.6
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• pp.441-445
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• 2003

New sulfonated amino ribofuranans were synthesized to elucidate the relationship between structure and specific biological activities such as anti-HIV and blood anticoagulant activities. The synthesis was performed by sulfonation of copolymers having various proportion of (1$\rightarrow5)-\alpha$-D-ribofuranosidic unit. The sulfonation with piperidine N-sulfonic acid produced the sulfonated amino ribofuranans in high yield. The anti-HIV activity of sulfonated 3-amino-3-deoxy-(1$\rightarrow5)-\alpha$-D-ribofuranan showed more potent by increasing the degree of sulfonation and the average molecular weights. This activity was almost equal to the activities of sulfonated ribofuranans and ribopyranans reported before in spite of low molecular weight. The blood anticoagulant activities was observed at 36-48 mg/units, more potent than standard dextran sulfonate, 22.7 mg/units. In addition, the blood anticoagulant activities of sulfamide-copolysaccharide consisting various proportion of (1$\rightarrow5)-\alpha$-D-ribofuranan units were potentiated by increasing sulfonated amino-ribofuranan units from 13 to 21 mg/units.

• Journal of Biomedical Engineering Research
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• v.15 no.2
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• pp.195-200
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• 1994

To develop an artificial bone substitute that is gradually degraded and replaced by the regenerated natural bone, the authors designed a composite that consists consisted of calcium phosphate and collagen according to the natural bone's main composition. The crystallinity of the synthesized apatite was shown to depend on the synthesis temperature. Carbonate apatite synthesized at $58{\circ}C$ demonstrated crystallinity very similar to that of the natural bone. By sintering the apatite over $700{\circ}C$ in vacuum, porous carbonate apatite could be obtained, and the pore extent was controllable according to the additive hydrogenperoxide volume.

• Archives of Pharmacal Research
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• v.26 no.9
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• pp.686-696
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• 2003

Ethyl (coumarin-4-oxy)acetate 1 was prepared through the reaction of 4-hydroxycoumarin with ethyl bromoacetate. Compound 1 was allowed to react with hydrazine hydrate to produce coumarin-4-oxyacetic hydrazide 2. The synthesis of N-(arylidene and alkylidene)-coumarin-4-oxyacetic hydrazones 3-20 was performed. The preparation of 2-substituted-3-[(coumarin-4-oxy) acetamido]thiazolidinones 21-26 and 2-[(coumarin-4-oxy )methyl]-4-acetyl-5-substituted-$\Delta^2$-1,3,4-oxadiazolines 27-33 was performed by the reaction of the hydrazones 3, 4, 7, 9, 12, 14 with mercaptoacetic acid and the hydrazones 3, 4, 5, 7, 12, 15, 16 with acetic anhydride, respectively. The antiviral activities, cytotoxicities and structure-activity relationship (SAR) towards different microorganisms of the prepared compounds were studied.

• Proceedings of the PSK Conference
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• 2002.10a
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• pp.364.2-364.2
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• 2002

(S) and (R) 12-HETE. endogenous eicosanoids. have recently been discovered to be implicated in a number of important biological activities. In particular. it has recently been reported by us that both the capsaicin-activated channel of sensory neurons and the cloned capsaicin receptor (VR1) are activated by the eicosanoids including these metabolites. We report herein a novel and efficient asymmetric synthesis of highly enantiomerically enriched 12(S)-HETE via enzymatic kinetic resolution of the key allylic alcohol synthon. (omitted)

• Journal of the Society of Cosmetic Scientists of Korea
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• v.37 no.3
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• pp.211-218
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• 2011

Effects of Kenpaullone, a specific inhibitor of GSK3${\beta}$, on melanin synthesis in B16 melanoma cells and human melanocytes were investigated. Kenpaullone showed a melanogenesis stimulation activity in a concentrationdependent manner in murine B16 melanoma cells and human melanocytes without any significant effects on cell proliferation. Tyrosinase activity was increased 48 h after treatment of B16 cells with Kenpaullone. The protein expression level of tyrosinase was dose-dependently enhanced after the treatment with Kenpaullone. At the same time, the expression level of tyrosinase mRNA was also increased after addition of Kenpaullone. The stimulatory effect of Kenpaullone mainly resulted from increased expression of tyrosinase. These findings suggest that the application of GSK3${\beta}$ inhibitors may be a potential therapeutic agent for the treatment of hypopigmentation disorder.