• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2000.04b
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• pp.143-146
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• 2000

We studied effects of alkyl($C_nH_{2n+1}$) chain length on characteristics of poly(3-alkylthiophene) electroluminescent diodes. Among the poly(3-alkylthiophene), poly(3-hexylthiophene)(n=6) and poly(3- octyIthiophene)(n=8) were mainly used for the emitting layer of the diode. The result of experiment, the emission intensity of poly(3-alkylthiophene) electroluminescent diodes depends on the alkyl chain length. Strong emission is obtained from a poly(3-alkylthiophene) diodes of long alkyl side chain length. Emission intensities are enhanced by a confinement of carriers on a main chain with a long interchain distance caused by a long alkyl side chain.

• YAKHAK HOEJI
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• v.35 no.4
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• pp.258-263
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• 1991

Seven drivatives of 2, 3-alkyl substituted aziridinecarboximidates were prepared from alkyl substituted alkene and cyanamide. Their ED$_{50}$ values against L$_{1210}$ cell in vitro were evaluated as 1.5 to 4 $\mu\textrm{g}$/ml.

• Mass Spectrometry Letters
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• v.6 no.3
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• pp.65-70
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• 2015

N-Alkyl/benzyl substituted isatin derivatives are intermediates and synthetic precursors for the preparation of biological active heterocycles. N-alkyl/benzyl isatins have showed various biological activities, such as cytotoxicity, antiviral, caspase inhibition, cannabinoid receptor 2 agonists for the treatment of neuropathic pain, etc. In this study, N-alkyl/benzyl isatin derivatives were synthesized from isatin and alkyl/benzyl halides in presence of K₂CO₃ in DMF and excellent to quantitative yields (~95%) were obtained. Isatins and benzyl-isatins were condensed with fluorescein hydrazide to form fluorescein hydrazone. All the compounds were subjected to their fragmentation behavior study using LC/MSⁿ. N-Alkyl substituted isatin derivatives fragmented at nitrogen-carbon (N-C) bond, hence gave daughter ion as [RN+H]⁺. Whereas, N-benzyl substituted isatin derivatives fragmented at carbon-carbon (C-C) bond of alkyl chain which linked with nitrogen molecules, therefore gave N-methyl fragments [RNCH₂]⁺. This study demonstrated that, isatin moiety present in a small/large molecule or in a matrix of reaction mixture with/without N-alkyl/benzyl substituents can be identified by mass spectroscopic fragmentation behavior study.

• YAKHAK HOEJI
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• v.53 no.5
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• pp.281-285
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• 2009

The retention of solutes in reversed-phase high-performance liquid chromatography depends on their hydrophobicity. Although the retention behaviors of alkyl benzenes have been reported so far, quite a few authors have mentioned the retention behavior of alkyl benzenes with plural hydrophobicity parameters. In this sense, we were interested in the retention behaviors of alkyl benzenes having benzene moiety and increasing alkyl chain. In this study, we therefore investigated the retention behavior of alkyl benzenes in reversed-phase high-performance liquid chromatography in order to obtain information concerning the effects of the aromatic moiety and the carbon chain on the retention mechanism by comparing their capacity factor (k') in relation to the carbon chain length. The eluent acetonitrile ($CH_3CN$) showed high selectivity on alkyl benzenes, showing the high difference of capacity factor (${\Delta}log\;k'$) between toluene and octyl benzene. Indeed, the ${\Delta}log\;k'$ of 80% $CH_3CN$ represented 1.42- and 4.25-times longer than 90% MeOH and 60% THF, respectively. The hydrophobicity parameters, van der Waals volume, bond constant, partition constant, $\pi$-energy effect and enthalpy were evaluated with the capacity factor (k') of alkyl benzenes eluted on 80% CH3CN, 90% MeOH and 60% THF, respectively. The best eluent for predicting retention behavior of alkyl benzenes was 90% MeOH ($R^2$ 0.999). The three parameters, van der Waals volume, bond constant and partition constant were well coincident to log k' by increasing alkyl benzenes. However, $\pi$-energy effect and enthalpy were severely disagreeable. Taken together, van der Waals volume, bond constant and partition constant were a reliable parameters to predict the retention behaviors of alkyl benzenes on reversed-phase column.

• Journal of the Korean Chemical Society
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• v.10 no.1
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• pp.43-45
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• 1966

The rate of exchange of I atom between alkyl iodides(ethyl or methyl iodide) and $I_2$ in n-hexane have been determined using $II^{131}$. It is found that the escape of $CH_3$ radicals from a solvent cage is faster than $C_2H_5$ radicals and that photolysis of $C_2H_5I$ is almost identical to that in the case of $CH_3I$.

• Archives of Pharmacal Research
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• v.17 no.4
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• pp.281-283
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• 1994

5-sec-butylthiomethyl-5-alkyl (methyl or phenyl) hydantoins (3-x) were prepared by the reaction of sec-buylthiomethyl alkyl (methyl or phenyl) ketone (1-2), potassium cyanide and ammonium carbonate. 3-(2-Bromoethyl) hydantoins (5-6) were the reaction products of 5-sec-buythiomethyl-5-alkyl (methyl or phenyl) hydantoin and 1, 2-dibromothane in the presence of potassium hydroxide. Alkylation of 5 and 6 with an excess of alkyl (methyl or ethyl iodide in THF with sodium hydride as base gave three 1-alkyl (methyl or ethyl)-3-(2-bromoethyl) hydantoins (7-9). Treatment of the 2-bromothyl group with potassium thioacelate and triethylamine gave three 1-alkyl (methyl or ethyl)-3-92-acetylthioethyl) hydantoins (10-12). Hydrolysis of the 2-acetylthiuoethyl group with sodium hydroxide in methanol afforded the three 1-alkyl (methyl or ethyl)-3-(2-mercaptorthyl) hydantoins.

• Journal of the Korean Crystal Growth and Crystal Technology
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• v.8 no.3
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• pp.431-434
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• 1998

Layered basic copper acetate, $Cu(OH)(CH_3COO){cdot}H_2O$ was synthesized. Intercalation compounds of alkyl sulfonates into layered basic copper acetate have been synthesized via anionic exchange. From the X-ray diffraction data and the alkyl sulfonate size, the orientation of the intercalated alkyl sulfonate into layered basic copper acetate was determined.

• Bulletin of the Korean Chemical Society
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• v.18 no.8
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• pp.824-827
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• 1997

Bis(ethylene)rhodium(Ⅰ) chloride dimer reacted with vinylcyclopropane to give σ,η3-allylrhodium(Ⅲ) complex 3. Complex 3 underwent C-C bond cleavage of 8-quinolinyl ethyl ketone 11, to form η3-1,3-dimethylallylrhodium(Ⅲ) complex 8, which was reductively eliminated by trimethyl phosphite to give 8-quinolinyl-1-methylbut-2-enyl ketone (10). More sterically hindered 8-quinolinyl alkyl ketones were allowed to react with complex 3 to afford corresponding alkenes as well as a mixture of complex 8 and η3-1-ethylallyl rhodium(Ⅲ) complex 19, identified as 10 and 8-quinolinyl-pent-2-enyl ketone (20) after reductive elimination. 8-Quinolinyl alkyl ketone bearing a sterically hindered alkyl group showed less reactivity for C-C bond cleavage and higher 20/10 ratio compared with those having a less sterically hindered alkyl group, such as 8-quinolinyl ethyl ketone (11).

• Bulletin of the Korean Chemical Society
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• v.24 no.1
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• pp.75-80
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• 2003

The structures and complexation energies of penta-O-alkylated 1b and penta-O-tert-butyl ester 1e of p-tert-butylcalix[5]arene and their simplified structures (2b and 2e) toward a series of alkyl ammonium guests have been calculated by a semi-empirical AM1 method. For AM1 calculations, complexation efficiencies of the simplified host 2e are very similar to the values of host 1e. The complexes of simplified host 2e with alkyl ammonium ions also have been optimized by ab initio HF/6-31G method. The calculated complexation efficiencies for 2e by ab initio method have been found to be bigger in magnitude than the values obtained by AM1 calculations for linear alkyl ammonium guests. Calculation results show that all of the calix[5]aryl derivatives investigated in this study have much better complexation ability toward ammonium cation without alkyl group compared with other alkyl ammonium guests. Ab initio calculations also well duplicate the molecular discriminating behaviors of calix[5]arene derivative 2e between butyl ammonium ions: $n-BuNH_3^+\;>\;iso-BuNH_3^+\;>\;sec-BuNH_3^+\;>\;tert-BuNH_3^+$.

• Applied Biological Chemistry
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• v.51 no.3
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• pp.183-187
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• 2008

Alkyl thiosulfi(o)nates, analogs of allyl-2-propene-1-thiosulfinate isolated from Allium sativum and having antibacterial activity, were chemically synthesized and their biological activities were investigated. Alkyl thiosulfinates were prepared by oxidation of corresponding disulfides with organic peroxy acid, while alkyl thiosulfonates could be obtained by oxidation of the alkyl thiosulfinates using sodium periodate. All synthetic thiosulfi(o)nates showed antibacterial activity against Staphylococcus aureus B33 and antifungal activity against Candida utilis ATCC42416. Further more synthetic alkyl thiosulfonates displayed antioxidant activity and have also prevention effect of platelet aggregation induced by collagen in rat.