• 약학회지
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• 제40권1호
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• pp.46-51
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• 1996

Eight new D-1.3-dioxolanyl and L-1,3-oxathiolanyl nucleosides containing 5-phenyl- selenyl pyrimidine bases which are expected to have antiviral activity were synthesized. Condensation of D-1,3-dioxolane acetate and L-1,3-oxathiolane acetate with 5-phenylselenyl pyrimidines gave anomeric mixtures of their nucleosides which were separated by silicagel column chromatography.

• Archives of Pharmacal Research
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• 제17권3호
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• pp.170-174
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• 1994

We have synthesized various 6-substituted 2-oxo-purine nucleosides from key intemediate, 6-[(4-methylphenylthio)-2-oxo-9(2, 3, 5tri-o-acetyl-$\beta$-D-ribofuanoslyl)]-2, 3- dihydropurine in relatively high yields by one step nucleophilic substitution. Various isoguanosine, xanthosine analogs and other 2-oxo-purine nucleosides containing nitrogen, sulfur and oxygen at C-6 of purine base were easily obtained by this method. The structures of the products were established on the basis of their spectral data studies. And cytotoxicity of resulting synthetic 6-substituted-2-oxo-purine nucleosides against some tumor cell-lines was examined. $Ed_{50}$ values of these synthetic compounds were above $100\;{\mu}g/ml$ except isoguanosine, $N^6$-methyl isoguanosine and thioxanthosine analogs.

• Bulletin of the Korean Chemical Society
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• 제30권12호
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• pp.2949-2958
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• 2009

Massive deguanylation of guanine based-nucleosides induced by halogenated alkanes at the physiological condition have been observed. For the study of deguanylation effects by the different substituents and/or functionality in halogenated alkanes, diverse kinds of halogenated alkanes were incubated with guanine based-nucleosides (ddG, dG and guanosine) for 48 h at the physiological condition (pH 7.4, 37$^{\circ}C$), which were analyzed by HPLC and further confirmed by LC-MS. Among the sixteen different halogenated alkanes, we observed massive deguanylation of nucleosides by 2-bromo-2-methylpropane, 2,3-dibromopropene, 2-bromopropane, bromoethane and 2-iodopropane. The order of deguanylation rate was highest in 2-bromo-2-methylpropane followed by 2,3-dibromopropene, 2-bromopropane, bromoethane and 2-iodopropane. In addition, time and dose response relationship of deguanylation in guanine basednucleosides induced by 2-bromo-2-methylpropane, 2,3-dibromopropene, 2-bromopropane, bromoethane and 2-iodopropane at the physiological condition were investigated. Deguanylation of calf thymus DNA induced by halogenated alkanes was also investigated. These results suggest that the toxic effect of certain halogenated alkanes might be from the depurination of nucleosides.

• Bulletin of the Korean Chemical Society
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• 제23권12호
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• pp.1790-1800
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• 2002

The DNA nucleosides(dA, dC, dG, dT)bound to gold nanoparticles (~13 nm) in aqueous solution has been studied as a probe by the SERS and their coordination structures have been proposed on the basis of them. According to UV-Visible absorption of gold nanoparticles after modifying with DNA nucleosides, the rates of absorption of dA, dC, and dG were much faster than that of dT as monitored by the aggregation kinetics at 700 nm. These data indicated that the nucleosides dA, dC, and dG had a higher affinity for the gold nanoparticles surface than nucleoside dT. As the result of SERS spectra, the binding modes of each of the nucleosides on gold nanoparticles have been assigned. A dA binds to gold nanoparticles via a N(7) nitrogen atom of the imidazole ring, which the C(6)-$NH_2$ group also participates in the coordination process. In the case of dC, it binds to the gold surface via a N(3) nitrogen atom of the pyrimidine ring with a partial contribution from the oxygen of C(2)=O group. A coordination of dG to the gold surfaces is also proposed. Although the dG has the two different nitrogens of a pyrimidine ring and the amino group, the N(1) nitrogen atom of a pyrimidine ring has a higher affinity after the hydrogen migrates to the amino group. Conversely, dT binds via the oxygen of the C(4)=O group of the pyrimidine ring. Accordingly, these data suggest that the nitrogen atom of the imidazole or the pyrimidine ring in the DNA nucleosides will bind more fast to the gold nanoparticles surfaces than the oxygen atom of the carbonyl group.

• Archives of Pharmacal Research
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• 제28권10호
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• pp.1105-1110
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• 2005

Novel anomeric branched carbocyclic nucleosides were synthesized from 1,3-dihydroxy acetone. 4'-Hydroxymethyl was installed by [3,3]-sigmatropic rearrangement reaction and 1'-methyl group was introduced by carbonyl addition of methylmagnesium bromide. The coupling of nucleosidic bases and desilylation afforded a series of novel nucleosides. The synthesized compounds $16{\~}19$ were evaluated for their antiviral activity against HIV-1, HSV-1, HSV-2, and EMCV. Compounds 16 and 19 exhibit toxicity non-related to any anti-HIV-1 activity.

• Archives of Pharmacal Research
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• 제26권12호
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• pp.1109-1116
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• 2003

A series of 3'- and 4'-branched carbocyclic nucleosides 25, 26, 27, 28, 29 and 30 were synthesized starting from simple acyclic ketone derivatives. The construction of the required quaternary carbon was made using a [3,3]-sigmatropic rearrangement. In addition, the installation of a methyl group in the 3'-position was accomplished using a Horner-Wadsworth-Emmons (HWE) reaction with triethyl 2-phosphonopropionate. Bis-vinyl was successfully cyclized using a Grubbs' catalyst (Ⅱ). Natural bases (adenine, cytosine, uracil) were efficiently coupled with the use of a Pd(0) catalyst.

• Bulletin of the Korean Chemical Society
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• 제24권9호
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• pp.1284-1288
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• 2003

A very short and concise synthetic route for a novel acyclic version of d4T is described. The required quaternary carbon was successfully installed using a [3,3]-sigmatropic rearrangement. The condensation of the mesylates 16-18 with an adenine base under standard nucleophilic substitution conditions ($K_2CO_3$, 18-Crown- 6, DMF) in addition to deblocking afforded the target acyclic nucleosides 22-24. In addition, the antiviral evaluations against various viruses were performed.

• 대한약학회:학술대회논문집
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• 대한약학회 2002년도 Proceedings of the Convention of the Pharmaceutical Society of Korea Vol.2
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• pp.356.1-356.1
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• 2002

The carbocyclic nucleosides have extensively studied as a promising antiviral agents having chemical and metabolical stability. In our research program for discovery of antiviral drugs. some novel dimethylcyclopropyl nucleosides possessing additional methyl spacer between purine bases and the ring was synthesized. The important intermediate, dimethylcyclopropyl alcohol was synthesized from ethyl chrysanthemate via its ozonolysis, isomerization reduction. (omitted)

• 대한약학회:학술대회논문집
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• 대한약학회 2002년도 Proceedings of the Convention of the Pharmaceutical Society of Korea Vol.2
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• pp.233.2-233.2
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• 2002

Apio nucleosides whose 4'-hydroxymethyl group moves to 3'-position exhibit interesting biological activity such as antitumor or antiviral activity. On the other hand. neplanocin A is the representative of the carbocyclic nucleosides and has been recognized as a potent antitumor and antiviral agent. Based on these findings. it was of great interest to design apio neplanocia A which combined the properties of apio nucleosides and neplanocin A. (omitted)

• 대한약학회:학술대회논문집
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• 대한약학회 2002년도 Proceedings of the Convention of the Pharmaceutical Society of Korea Vol.2
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• pp.354.1-354.1
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• 2002

Carbocyclic nucleosides are unique class in which a methylene group replaces the oxygen in the furan, which result in metabolic stability to endogenous phosphorylase. The biologically active natural carbocyclic nucleosides such as aristeromycin and neplanocin were found to possess interesting biological properties including antiviral and antitumor activity. (omitted)