• Bulletin of the Korean Chemical Society
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• v.14 no.1
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• pp.52-55
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• 1993

A procedure is described for the synthesis of the title compound via phosphotriester intermediates. The preparation of $R_p\;and\;S_p$ diastereomeric dinucleotide of d[Ap(S)A] was performed by the condensation of protected deoxyadenosine, 2,5-dichlorophenylphosphorodichloridothioate and 1-hydroxybenzotriazole in THF. Their designation of configuration at phosphorus as $R_p\;and\;S_p$ follows from analysis of $^{31}P$-NMR spectroscopy and reversed-phase HPLC and the stereospecificity in the hydrolysis catalyzed by nuclease Pl.

• Journal of the Korean Chemical Society
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• v.65 no.2
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• pp.121-124
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• 2021

RNA molecules which bind to the G-rich sequence in the 5'-UTR RNA which plays an important role in expression of N-ras, were selected. The secondary structures of five selected RNA aptamers including primer sequence were found by the CLC RNA workbench ver. 4.2 program (www.clcbio.com) and investigated with RNA structural probes such as RNase T1 which has specificity for a G in single-stranded region, RNase V1 specific for double strand and nuclease S1 specific for single strand. The generalized secondary structure model was proposed and characterized. It was composed of a central long double strand region flanked by single strand region at both end sides. The double strand region had an internal single-strand region and bulges. The single strand loop in the right side was composed of four or five nucleotides.

• Bulletin of the Korean Chemical Society
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• v.28 no.2
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• pp.263-270
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• 2007

New mono- and bis-Cu(II)-triazacyclononane(tacn) complex that conjugated with 9-aminoacridine were synthesized, and their binding modes and DNA cleavage activity were investigated in this study. When the classic intercalator, 9-aminoacridine, was conjugated to mono- and bis-Cu(II)-tacn complexes, a significant red-shift and hypochromism in absorption spectrum was apparent in the acridine absorption region upon binding to DNA. Furthermore, the magnitude of the negative reduced linear dichroism signal in the substrate absorption region appeared to be larger than that in the DNA absorption region. These spectral observations indicated that the acridine moiety intercalated when the Cu(II)-tacn complex was conjugated. In contrast, from a close analysis of the circular and linear dichroism spectrum, the aminoacridine-free bis-Cu(II)-tacn complex was concluded to bind at the phosphate groups of DNA. The 9-aminoacridine-free-bis-Cu(II)-tacn complex produces the nicked and linear DNA. On the other hand, 9-aminoacridine conjugated mono-and bis-Cu(II)-tacn complexes showed unspecific binding with negligible DNA cleavage.

• Journal of the Korean Chemical Society
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• v.43 no.3
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• pp.307-314
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• 1999

Ml RNA, the RNA component of RNase P from Escherichia coli, is produced by 3' processing of pre-Ml RNA, a major primary transcript of the rnpB gene. The enzyme fraction containing the processing activity was partially purified and characterized. Since exposure of the active fraction to the high salt condition results in the inactivation of the processing activity, the processing enzyme seems to be an enzyme complex composed of multiple enzymes. The enzyme fraction loses the processing activity when treated with the chemical nuclease lead(II) ion, but regains its activity by the addition of RNA isolated from the enzyme fraction itself, suggesting that an RNA molecule(s) may be essential for the processing activity. Analysis of cleavage sites produced by the partially purified enzyme fraction also implies that the 3' processing occurs by multiple enzymes and at least in two distinct pathways.

• The Korean Journal of Pesticide Science
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• v.4 no.1
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• pp.32-37
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• 2000

A series of transition metal complexes of 3,6-bis(6'-methyl-2'-pyridyl)pyridazine ($L^{1}$) and 3,6-bis(2'-pyridyl)pyridazine ($L^{2}$) as artificial nuclease, $1{\sim}8$ were synthesized. After determining of X-ray crystal structure, hydrolysis rate constants of phosphates, as DNA model compound and biological activities were confirmed. $L^{2}$-Zn(II) complex, 8 was shown the best hydrolysis rate constant. The $L^{2}$-Ni(II) complex, 5 and $L^{2}$-Co(II) complex, 6 showed the highest herbicidal activity against SCP (Scriptus Juncoids) with excellent tolerance to rice, ORY (Oryzae sativa L.). And the $L^{1}$-Co(II) complex, 2, $L^{1}$-Zn(II) complex, 4 and ligand ($L^{1}$ amp; $L^{2}$) displayed above 90% fungicidal activity against MAG (Magnaporthe grisea).

• Journal of the Society of Cosmetic Scientists of Korea
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• v.45 no.4
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• pp.389-397
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• 2019

Lysosomes are cellular organelles involved in energy metabolism and intracellular digestion in eukaryotic cells, including protease, nuclease, glycosidase, lipase, and phosphatase. Our previous studies have confirmed that egg white lysosomes had melanin decolorization and reduction activity. However, there have been few studies on skin barrier and skin regeneration as well as inhibition of melanin production by egg white lysosomes on B16F10 melanocyte cell line. In this study, we attempted to identify the effect of lysosome-related organelle extract (LOE) extracted from egg white on the melanin content change and skin barrier enhancement in cells. First, cytotoxicity evaluation was performed on B16F10 melanocyte cell line to confirm the whitening efficacy of LOE. Cytotoxicity by LOE was not observed at 20 mg/mL concentration, but cytotoxicity was observed at 40 mg/mL, and the maximum concentration value was set to 20 mg/mL in all subsequent experiments. LOE samples of 5, 10, 20 mg/mL inhibited melanin production by 61.5 ± 4.0%, 61.4 ± 7.3%, 58.3 ± 8.3%, respectivly, compared to α-MSH, a negative control in melanin contents assay. MITF mRNA expression was reduced by about 39.7 ± 3.2% compared to the α-MSH treatment group. TEER assay using HaCaT showed that LOE increased TEER resistance in a dose-dependent manner, indicating that LOE is involved in strengthening the skin barrier. LOE also increased the TEER resistance under TNF-α treatment. Skin barrier was normally restored by LOE even under the condition of inflammation. LOE had a positive effect on cell division and cell migration promotion, confirmed by the observing the effect of promoting cell migration by LOE through cell migration assay. Taken together, we expect that LOE can be developed as a cosmetic material to enhance has effects on skin regeneration and skin barrier strengthening as well as whitening function if enzyme stabilization and formulation technology are combined.