• Journal of the Korean Chemical Society
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• v.40 no.8
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• pp.565-570
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• 1996

A simple and efficient new synthetic method of 4'-[N-(9-acridinyl)]-1'-(N-methanesulfonyl)-3'-methoxyquinonediimide(AMQD, 5) was developed and six new nucleophilic adducts(6a-6f) were prepared by the addition of thiophenol derivatives to AMQD. The structures of these compounds were confirmed by elemental analysis, mass, ir and nmr spectra.

• Journal of the Korean Chemical Society
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• v.18 no.4
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• pp.251-258
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• 1974

The rate constants for the nucleophilic substitution reactions of substituted benzoyl chlorides with p-nitroaniline in such solvents as acetone, acetonitrile, methanol, ethanol, etc. were conductometrically determined, and the activation thermodynamic parameters were also evaluated. In result, the reaction rates were faster in protic solvents than in aprotic solvent; in the solvents of similar property, the reaction rate in the solvent of the large dielectric constant was faster than that in the solvent of the small dielectric constant. Hammett plots in individual solvents showed the straight lines with positive slope; and we concluded that the reaction occurred via the addition-elimination mechanism.

• Archives of Pharmacal Research
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• v.28 no.7
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• pp.745-749
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• 2005

A simple synthetic route for the synthesis of novel methyl branched cyclopropyl phosphonic acid nucleosides is described. The characteristic cyclopropyl moiety 8 was constructed by employing Simmons-Smith reaction as a key step. The condensation of mesylate 11 with natural nucleosidic bases (A,C,T,U) under standard nucleophilic substitution conditions ($K_2CO_3$, 18-Crown-6, DMF) and after subsequent hydrolysis resulted in the formation of target nucleosides, 16, 17, 18, and 19. In addition, the antiviral evaluations of the synthesized nucleotides against various viruses were also performed.

• Journal of the Korean Applied Science and Technology
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• v.4 no.1
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• pp.61-66
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• 1987

2,4,6-Triamino-5-nitrosopyrimidine was prepared using malononitrile and guanidine carbonate, and acetylated refluxing in acetic acid with acetic anhydride in order to activate the nitroso group for nucleophilic attack. Nucleophilic attack of phenylpyrimidium bromide on the nitroso group of 2,4,6-triacetamido-5-nitrosopyrimidine gave the intermediate, which lost pyrdidine to give the nitrone derivative. Addition of the methanethiol anion to nitrone gave 2,4-diacetamido-7-phenyl-6-methylthiopteridine which was hydrolyzed to give 2,4-diamino-7-phenyl-6-methylthiopteridine. Spectral data (IR, M.S, NMR) were provided to identify the reaction products during synthesis.

• Bulletin of the Korean Chemical Society
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• v.15 no.11
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• pp.985-990
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• 1994

Cross-interaction constants, ${\rho}^e_{XY}$, ${\rho}_{YZ}$ and ${\rho}_{XZ}$ are defined using observed rate constant, k_N=(k_1/k_{-1})k_2=Kk_2$, for the stepwise carbonyl addition reactions involving the rate-limiting breakdown of a tetrahedral intermediate $(T^{\pm})$. Abundant experimental evidence in the literature enables us to determine signs for the three constants for such mechanism, ${\rho}^e_{XY}$>0, ${\rho}_{YZ}$<0 and ${\rho}_{XZ}$0. These are in contrast to those for the concerted $S_N2$ mechanism, ${\rho}_{XY}$<0, ${\rho}_{YZ}$>0 and ${\rho}_{XZ}$, and provide useful mechanistic criteria. In the light of these criteria, mechanisms of some nucleophilic reactions of carbonyl compounds are re-examined.

• Journal of the Korean Chemical Society
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• v.38 no.6
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• pp.442-448
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• 1994

The rate constants of the nucleophilic reaction of ${\alpha}$-(n-butyl)-N-phenylnitrone and its derivatives have been determined by ultraviolet spectrophotometry at $25^{\circ}C$ and a rate equation which can be applied over a wide pH range was obtained. Final product of the addition reaction was $\alpha$-phenylthiobutylidene-aniline. Base on the rate equation, genernal base effect, substituent effect and final product, plausible mechanism of addition reaction have been proposed. Below pH 3.0 the reaction was inititated by the addition of thiophenol, and in the range of pH 3.0∼10.0, proceeded by the competitive addition of thiophenol and thiophenoxide anion. Above the pH 10.0, the reaction proceeded through the addition of a thiophenoxide anion.

• Journal of the Korean Chemical Society
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• v.12 no.4
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• pp.177-183
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• 1968

The rate equations for the nucleophilic addition reactions of n-propyl- and tert-buryl mercaptan to 3,4-methylenedioxy-$\beta$-nitrostyrene over wide pH range were obtained. From this equations, the rate constants for n-propyl-and tert-butylmercaptide ions at high pH were obtained numerically as $1.26{\times}10^8$ and $3.98{\times}10^6\;M^{-2},\;sec^{-1}$, and for n-propyl- and tert-butyl mercaptan at low pH, $7.07{\times}10^{-3}$ and $1.5{\times}10^3\;M^{-1},\;sec^{-1}$ respectively.

• Bulletin of the Korean Chemical Society
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• v.28 no.7
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• pp.1217-1220
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• 2007

• Bulletin of the Korean Chemical Society
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• v.34 no.3
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• pp.989-992
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• 2013

• Bulletin of the Korean Chemical Society
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• v.24 no.9
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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.