• Bulletin of the Korean Chemical Society
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• v.25 no.2
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• pp.260-262
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• 2004

In agreement with the results of previous MP2 calculations by Sauers, B3LYP, CASSCF, and CASPT2 calculations on the parent 2-carbena-1,3-dioxolane show that it fragments to ethylene plus $CO_2$ by a concerted pathway with only a small energy barrier. Not only is fragmentation via stepwise C-O bond cleavage computed to be a much higher energy pathway, but the singlet diradical that would be an intermediate along such a reaction path is not even computed to be a local minimum on the potential energy surface.

• Proceedings of the Korean Society for Bioinformatics Conference
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• 2005.09a
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• pp.10-14
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• 2005

In this paper, we highlight the development of a web application system. Its main objective is to provide pathway visualization functionalities for inter-cytokine relationships, as well as for other types of relationships, with a specific cytokine(s) of interest. A natural language processor is first used to extract information from a certain web page that concerns the cytokine(s) of interest. The results obtained are then further processed and then displayed graphically to the user. The system displays how the cytokine(s) of interest interacts with other cytokines and cells. Useful information such as the type of reaction and catalyst involved, if any, are also displayed. In addition, the system also offers functionalities for graphical manipulations of the visualized pathways. The system has been shown to provide better overview, and hence, improved learning to readers who are new to this field by virtue of accurate inputs obtained from the natural language processing module.

• Journal of Microbiology and Biotechnology
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• v.7 no.4
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• pp.237-241
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• 1997

Two isolated strains, Comamonas testosteroni CPW301 and Arthrobacter ureafaciens CPR706, were able to use 4-chlorophenol (4-CP) as a sole carbon and energy source. CPW301 was found to degrade 4-CP via a meta-cleavage pathway in which the chloro-substituent was eliminated even when 4-chlorocatechol was cleaved by the catechol 2, 3-dioxygenase. In contrast, CPR706 removed chloride from 4-CP prior to the ring-fission reaction, producing hydroquinone as a transient intermediate during 4-CP degradation. CPR706 exhibited much higher tolerance for 4-CP than CPW301, which was indicated by the maximum degradable concentration and degradation rate.

• Bulletin of the Korean Chemical Society
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• v.34 no.10
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• pp.2989-2994
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• 2013

The solvolysis rate constants of 3,4- (1) and 3,5-dimethoxybenzoyl (2) chlorides were measured in various pure and binary solvents at $25.0^{\circ}C$, and studied by application of the extended Grunwald-Winstein (G-W) equation, kinetic solvent isotope effect in methanolysis and activation parameters. The solvolysis of 1 was interpreted as the unimolecular pathway due to a predominant resonance effect from para-methoxy substituent like 4-methoxybenzoyl chloride (3), while that of 2 was evaluated as the dual mechanism, with unimolecular or bimolecular reaction pathway according to the character of solvent systems (high electrophilic/nucleophilic) chosen, caused by the inductive effect by two meta-methoxy substituents, no resonance one. In the solvolyses of 1 and 2 with two $-OCH_3$ groups, the resonance effect of para-methoxy substituent is more important to decide the mechanism than the inductive effect with other corresponding evidences.

• Journal of Korea Technical Association of The Pulp and Paper Industry
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• v.37 no.5 s.113
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• pp.35-40
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• 2005

We tried to synthesize the 2-methyl anthraquinone (2-MAQ) with reaction between phthalic anhydride and toluene instead of using 2-methyl phthalic anhydride and benzene. This process didn't generate significant of amount of 1-methyl anthraquinone (l-MAQ) as byproduct. The other advantage of this pathway is using less toxic toluene instead of benzene known as carcinogen. 2-MAQ synthesized this pathway was as effective as reagent grade from commercial available based on soda-anthraquinone(AQ) pulping results.

• Mass Spectrometry Letters
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• v.9 no.1
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• pp.37-40
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• 2018

Farinomalein is a maleimide-bearing compound well known for its anti-fungal activity. In the present study, synthesis of farinomalein is achieved via Stobbe condensation followed by Haval-Argade contrathermodynamic rearrangement. Kinetically driven Stobbe condensation followed by condensation with beta-alanine reveals formation of two isomers of farinomalein. This article describes application of LC-MS/MS in structure elucidation of farinomalein 1 and its isomers 2 and 3 encountered in its synthesis. The proposed distinct fragmentation pathway is supported by rational organic reaction mechanism. These fragmentation pathways are significant for analytical method development of farinomalein in near future. The structures of farinomalein 1 and its isomers 2 and 3 have been assigned undisputedly.

• Textile Coloration and Finishing
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• v.24 no.1
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• pp.39-44
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• 2012

To improve flame retardation of poly(ethylene terephthalate) (PET) against burning, resorcinol bis(diphenyl phosphate) (RDP), phosphorous containing flame retardant, was incorporated into PET backbone by radical reaction pathway. Radical endcapping of PET with RDP was confirmed by spectroscopic and thermal analysis. From 400 MHz $^{31}P$ solid state FT-NMR spectrum of PET with RDP (PET-RDP), phosphorus spectra peak in RDP was found at ca. -10 ppm. Furthermore, P-C bond stretching vibration peaks were found ca. $530cm^{-1}$ in FT-IR spectrums of PET-RDP. These results indicated that RDP can be chemically bound at the ends of PET by radical addition method. Thermal characteristics of pure PET (pPET) and PET-RDP were measured and evaluated by TGA thermal analysis. There was not significant changes in thermal characteristics of PET-RDP compared to that of pPET.

• Bulletin of the Korean Chemical Society
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• v.33 no.11
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• pp.3607-3617
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• 2012

In this paper, the study of various ortho- and meta-substituted Magnolol derivatives is presented. The reaction enthalpies related to three antioxidant action mechanisms HAT, SET-PT and SPLET for substituted Magnolols have been calculated using DFT/B3LYP method in gas-phase and water. Calculated results show that electron-withdrawing substituents increase the bond dissociation enthalpy (BDE), ionization potential (IP) and oxidation/reduction enthalpy (O/RE), while electron-donating ones cause a rise in the proton dissociation enthalpy (PDE) and proton affinity (PA). In ortho- position, substituents show larger effect on reaction enthalpies than in meta-position. In comparison to gas-phase, water attenuates the substituent effect on all reaction enthalpies. In gas-phase, BDEs are lower than PAs and IPs, i.e. HAT represents the thermodynamically preferred pathway. On the other hand, SPLET mechanism represents the thermodynamically favored process in water. Results show that calculated enthalpies can be successfully correlated with Hammett constants (${\sigma}_m$) of the substituted Magnolols. Furthermore, calculated IP and PA values for substituted Magnolols show linear dependence on the energy of the highest occupied molecular orbital ($E_{HOMO}$).

• Bulletin of the Korean Chemical Society
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• v.33 no.7
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• pp.2269-2273
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• 2012

Pseudo-first-order rate constants $k_{amine}$ have been measured spectrophotometrically for the reactions of benzyl 4-pyridyl carbonate 6 with a series of alicyclic secondary amines in $H_2O$ at $25.0^{\circ}C$. The plots of $k_{amine}$ vs. [amine] curve upward, indicating that the reactions proceed through a stepwise mechanism with two intermediates, a zwitterionic tetrahedral intermediate $T^{\pm}$ and its deprotonated form $T^-$. This contrasts to the report that the corresponding reactions of benzyl 2-pyridyl carbonate 5 proceed through a forced concerted pathway. The $k_{amine}$ values for the reactions of 6 have been dissected into the second-order rate constant $Kk_2$ and the thirdorder rate constant $Kk_3$. The Br${\o}$nsted-type plots are linear with ${\beta}_{nuc}=0.94$ and 1.18 for $Kk_2$ and $Kk_3$, respectively. The $Kk_2$ for the reaction of 6 is smaller than the second-order rate constant $k_N$ for the corresponding reaction of 5, although 4-pyridyloxide in 6 is less basic and a better nucleofuge than 2-pyridyloxide in 5.

• The Journal of Korean Medicine Ophthalmology and Otolaryngology and Dermatology
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• v.13 no.1
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• pp.116-128
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• 2000

Anal therapy is another way of taking medicine It is a traditional pathway but not available in common situation. Nevertheless. It has many benefit and usefulness, it has not treated so much. The dried immature fruit of Poncirus trifoliata L(Ji-Sil) is widely used to treat urticaria, itch and indigestion in traditional Korean Medicine. So this study was carried out to examine the effect of an aqueous extract from immature fruit of Poncirus trifoliate L. on immediate-type allergic reaction by anal administration. Anal administration of Poncirus trifoliata L. showed a marked inhibition rate in systemic immediate-type allergic reaction with a dose of 0.1 - 1 g/kg 1 hr before intraperitoneal injection of compound 48/80. Anal administration of Poncirus tnjoliata L. (0.1 -1 g/kg) significant1y reduced plasma histamine contents induced by compound 48/80. Anal administration of Poncirus trifoliata L. (10 g/kg) also inhibited to $44.6\%$ (P<0.01) local allergic reaction activated by anti-dinitrophenyl (DNP) IgE. In addition, Syzygium aromaticum dose-dependently inhibited the histamine release from the peritoneal mast cells by compound 48/80 or anti-DNP IgE. These results provide evidence that anal therapy of Poncirus trifoliata L. may be beneficial in the treatment of systemic and local immediate-type hypersensitivity by inhibition of histamine release from mast cells in vivo and in vitro.