• Bulletin of the Korean Chemical Society
• /
• v.32 no.3
• /
• pp.1022-1026
• /
• 2011

The syntheses of DTPA-bis(amide) conjugates of phosphonated cyclohexane moieties (5a-d) and their Gd(III) complexes of the type $[Gd(L)(H_2O)]{\cdot}nH_2O$ (6a-d; L = 5a-d) are described. All new compounds have been characterized by microanalysis and spectroscopic techniques. High $r_1$ relaxivities of aqueous solutions of 6a-d are observed to be in the range of $10.7-18.3\;mM^{-1}sec^{-1}$, which compare much better than that of $Omniscan^{(R)}$ ($r_1=3.90\;mM^{-1}sec^{-1}$).

• Journal of Physiology & Pathology in Korean Medicine
• /
• v.19 no.2
• /
• pp.520-523
• /
• 2005

(R)-(-)-PGME amide of diterpene acid (2) was assigned the absolute configuration from NMR correlation experiments. The compound (2) was tested for its growth inhibitory effects against tumor cell lines by the MTT method.

• Bulletin of the Korean Chemical Society
• /
• v.7 no.1
• /
• pp.1-5
• /
• 1986

The influences of $LiNO_3\;and\;AgNO_3$ on the N-C(O) rotational barrier of N,N-dimethylacetamide and N,N-dimethylpropionamide have been investigated. The rotational activation free energy $({\Delta}G^{\neq})\;for\;Li^{+}$-amide complexes is found to increase with increasing salt concentration. On the other hand, that for $Ag^+$-amide complexes increases in the presence of $Ag^+$ ion up to 0.25 M ion concentration and then decreases as the concentration of $Ag^+$ ion is further increased. Such an unusual behavior of $Ag^+$-amide complexes has been interpreted in terms of ion-pairing and diluent effect on the amides. However, $^{13}C$ nmr chemical shift data for the amides have shown that both of these ions interact primarily with the carbonyl group in amides.

• Applied Chemistry for Engineering
• /
• v.23 no.4
• /
• pp.421-427
• /
• 2012

To improve the lubricity of ultra low sulfur diesel, vegetable oil-based alkanol amide derivatives were prepared and their lubricity properties were studied. To synthesize the alkanol amides, we conducted the amidation reaction of diethaolamine High Frequency Reciprocating Rig (HFRR) and the fatty acid methyl esters, obtained by the continuous transesterification of methanol and several vegetable oil, such as soybean oil, palm oil and coconut oil. The synthesized amides were soluble in ultra low sulfur diesel in the concentration range of ca. 1 wt%; the lubricating properties of ultra low sulfur diesel containing 120 ppm of amides were measured using an HFRR method. It was found that the wear scar diameter in the pure ultra low sulfur diesel decreased significantly from 581 ${\mu}m$ to 305~323 ${\mu}m$ upon the addition of the amides, indicating that lubricating properties of the diesel were improved. On the other hand, the types of vegetable oils did not affect the wear scar diameters, implying that lubricating properties of the diesel did not depend strongly on the structures of alkyl groups of alkanol amide derivatives. When we measured the lubricating properties of the one type of diesels containing various amounts of alkanol amide, we observed that the wear scar diameter decreased drastically with increasing the amide concentration, meaning that the lubricity improved with the amide concentration.

• KSTLE International Journal
• /
• v.8 no.1
• /
• pp.7-10
• /
• 2007

The rheological property of hollow PANI malonate suspension in silicone oil was investigated by varying the electric fields and shear rates, respectively. The hollow PANI malonate susepnsion showed a typical electrorheological (ER) response caused by the polarizability of an amide polar group and shear yield stress due to the formation of chains upon application of an electric field. The shear stress for the hollow PANI malonate suspension exhibited an electric field power of 0.90. On the basis of the experimental results, the newly synthesized hollow PANI malonate suspension was found to be an anhydrous ER fluid.

• Bulletin of the Korean Chemical Society
• /
• v.28 no.12
• /
• pp.2546-2548
• /
• 2007

• Archives of Pharmacal Research
• /
• v.28 no.1
• /
• pp.39-43
• /
• 2005

Eight compounds were isolated from the methanolic extract of the twigs of Celtis sinensis through repeated silica gel and Sephadex LH-20 column chromatography. Their chemical structures were elucidated as two triterpenoids, germanicol and epifriedelanol, two amide compounds, trans-N-caffeoyltyramine and cis-N-coumaroyltyramine, two lignan glycoside, pinoresinol glycoside and pinoresinol rutinoside, and two steroids by spectroscopic analysis.

• Bulletin of the Korean Chemical Society
• /
• v.35 no.7
• /
• pp.2189-2192
• /
• 2014

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

• KSTLE International Journal
• /
• v.7 no.1
• /
• pp.18-21
• /
• 2006

The electrorheology of hollow PANI derivative suspensions in silicone oil was investigated by varying the electric fields and shear rates, respectively. The hollow PANI derivative susepnsions showed a typical electrorheological (ER) response caused by the polarizability of an amide polar group and shear yield stress due to the formation of chains upon application of an electric field. The shear stress for the hollow PANI succinate suspension exhibited an electric field power of 0.67. On the basis of the experimental results, the newly synthesized hollow PANI derivative suspensions were found to be an anhydrous ER fluid.