• Bulletin of the Korean Chemical Society
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• v.27 no.9
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• pp.1353-1358
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• 2006

We investigated in vitro T-cell inhibitory activity and bioavailability of small chemical inhibitors for Lck SH2 domain, which had a different scaffold such as an amide bond, reduced amide bond, N-methyl amide bond, thioamide bond, and urethane bond. Each of these compounds, with its particular scaffold, showed a different logP value, stability against serum enzyme, stability in buffer solution, and in vitro T-cell inhibitory activity. Overall results indicated that the SH2 inhibitor containing urethane bond can be a new lead compound because of its superior bioavailability, potent in vitro T-cell inhibitory activity, and facile synthesis.

• Bulletin of the Korean Chemical Society
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• v.26 no.1
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• pp.161-164
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• 2005

• Bulletin of the Korean Chemical Society
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• v.23 no.9
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• pp.1208-1254
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• 2002

Photoreaction of N-(o-halophenyl)acetamide in basic acetonitrile produces an intramolecular substituted product, 2-methylbenzoxazole in addition to reduced product, acetanilide, whereas photoreaction of N-(o-halobenzyl) acetamide affords a reduced product, N-benzylacetamide only. On the basis of preparative reaction, kinetics, and UV/vis absorption behavior, an electrophilic aromatic substitution of aryl halide with oxygen of its amide bond are proposed.

• Journal of the Korean Applied Science and Technology
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• v.8 no.2
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• pp.115-122
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• 1991

Four novel amphoteric surfactants of N-(2-alkylamidoethyl)-N, N-dimethyl ammonioacetates were synthesized. The each reaction between four saturated fatty acids containing 10, 12, 14 and 16 carbon atoms and N, N-dimethylethylene diamine permitted to give the intermediate products, N-(2-alkylamidoethyl)-N, N-dimethylamines. Quaterinzation of these intermediates was permitted to form N-(2-alkylamidoethyl)-N, N-dimethyl, ammonioacetates, whose sturctures were identified by CC, TLC, elemental analysis, IR pectrophotometry and $^1$HNMR spectrometry. The products yielded from 48% to 58%. The isoelectric points were shown in the range of $4.30{\sim}6.64$. It showed a tendency to learn to the acidic site and its range was broadened as increase of the hydrophobic group length. Surface tensions of the aqueous solution in the $10^{-6}{\sim}10^{-1}$mol/l of amidobetaines were measured. and the critical micell concentration(cmc) were shown in the range of $8.37{\times}10^{-6}{\sim}8.96{\times}10^{-2}$mol/l, and ${\Gamma}_{cmc}$ were reduced to 32.3~38.2 dyne/cm. A linear relationship between log cmc and the number of carbon in the hydrophobic alkyl chain was presented by the formula of log cmc=2.38-0.5n, and the contribution-rate of n on the standard free energy change in micellization ${\partial}({\Delta}G^0$$_m)/{\partial}n$, was calulated as -0.5RT.

• Polymer(Korea)
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• v.28 no.5
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• pp.433-443
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• 2004

The membranes of the blends of chitosan and polycaprolactarn (PA6) were prepared in formic acid. FT-IR data revealed that hydrogen bonding between amide and hydroxyl groups of chitosan and PA6, respectively, was formed. Thermogravimetric analysis demonstrated that the blend samples contain water. DMA results showed that the dissipation of water in the samples significantly reduced the storage modulus (E'). The mechanical loss tangent (tan $\delta$) data of the blend samples showed the $\beta$d loss peak around $0^{\circ}C$. The blend samples were completely dried in a vacuum and then exposed to high moisture to absorb water which would cause, so called, w-bridges between the molecules. The E' data of these regained samples increased abnormally and additional loss peak appeared on the shoulder of the peak around $50^{\circ}C$. Under dry condition, the samples with a blend ratio of 40/60 for chitosan/PA6 displayed a better miscibility between two components.