• Journal of the Korean Mathematical Society
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• v.56 no.3
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• pp.623-644
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• 2019

We investigate the homotopy category ${\mathcal{K}}_N(Inj{\mathfrak{A}})$ of N-complexes of injectives in a Grothendieck abelian category ${\mathfrak{A}}$ not necessarily locally noetherian, and prove that the inclusion ${\mathcal{K}}_N(Inj{\mathfrak{A}}){\rightarrow}{\mathcal{K}}({\mathfrak{A}})$ has a left adjoint and ${\mathcal{K}}_N(Inj{\mathfrak{A}})$ is well generated. We also show that the homotopy category ${\mathcal{K}}_N(PrjR)$ of N-complexes of projectives is compactly generated whenever R is right coherent.

• Journal of Pharmaceutical Investigation
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• v.20 no.3
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• pp.153-159
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• 1990

To increase the solubility of fentiazac which is used widely as a non-steroidal antiinflammatory drug, its inclusion complex and suppositories were prepared and studied. Inclusion complexes of fentiazac with ${\beta}-cyclodertin$ $({\beta}-CyD)$ were prepared by four diffrent methods; coprecipitation method, kneading method, solvent evaporation method, freeze drying method. Suppositories of $fentiazac/{\beta}-CyD$ with PEG 1500 and Witepsol H-15 were prepared by solvent evaporation method and freeze drying method. Inclusion complex formation of fentiazac with ${\beta}-CyD$ was ascertained by powder X-ray diffractometry, differential scanning calorimetry and IR spectroscopy. The dissolution rate of fentiazac from the inclusion complex increased in distilled water and KP 2nd disintegration test fluids (pH 6.8) but extemly decreased in KP 1st disintegration test fluid (pH 1.2). Inclusion complexes prepared by freeze drying method and solvent evaporation method were similar. Freeze drying method seemed to be suitable for preparation of complex with most higher dissolution rate but coprecipitation method seemed not to be suitable. The dissolution rate of fentiazac increased markedly by ${\beta}-CyD$ complexation. The release rates of suppositories increased in the following order. Complex prepared by freeze dying method in PEG 1500 > complex prepared by solvent evaporation method in PEG 1500 > fentiazac in PEG 1500 > complex prepared by freeze dying method in Witepsol H-15 > complex prepared by solvent evaporation method in Witepsol H-15 > fentiazac in Witepsol H-15.

• Korean Chemical Engineering Research
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• v.43 no.1
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• pp.110-117
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• 2005

In this work, solid-state inclusion complex powders of itraconazole and $2-hydroxypropyl-{\beta}-cyclodextrin(HP-{\beta}-CD)$ were produced by a supercritical anti-solvent (SAS) process. In order to evaluate the degree of complexation, the thermal behavior of the microparticulate complexes was investigated using differential scanning calorimetry. The experimental results obtained for the solubility and dissolution rate of the microparticulate inclusion complexes in a buffer solution of pH 1.2 showed that the complexation of itraconazole with $HP-{\beta}-CD$ results in a significant increase in the solubility and dissolution rate of itraconazole. The particle size of the SAS-produced inclusion complexes was dramatically reduced ($<0.1-0.5{\mu}m$) compared with untreated itraconazole ($30-50{\mu}m$) and $HP-{\beta}-CD$ ($50-100{\mu}m$). The solubility of itraconazole was increased with the increase of pressure at a constant temperature to ca. $758.6{\mu}g/mL$ in an aqueous medium of pH 1.2. The dissolution rate of itraconazole was observed to be significantly improved and about 90% of itraconazole was found to be dissolved within 5-10 min.

• Analytical Science and Technology
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• v.17 no.1
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• pp.16-22
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• 2004

Inclusion complexes of the p-nitrophenol with ${\beta}$-cyclodextrin (CD), sulfated ${\beta}$-CD, and ${\beta}$-CD polymer cross-linked with epichlorohydrine (EP) were prepared and characterized by Raman spectroscopy. The intensity of vibration peaks of the C-O and C-N at 1284 and $856cm^{-1}$ of the p-nitrophenol in the presence of EP-linked CD polymer was remarkably increased, respectively. The vibration modes at 1284 and $856cm^{-1}$ are assigned to the out-of phase C-C-O stretching mode and the C-N stretching mode, respectively. The vibration peaks at 1284 and $856cm^{-1}$ increased with increasing the content of EP-linked CD polymers, while decreased with increasing the p-nitrophenol content. Furthermore, the vibration mode of the $NO_2$ symmetric stretch at $1344cm^{-1}$ enhanced with increasing the content of p-nitrophenol.

• Bulletin of the Korean Chemical Society
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• v.17 no.11
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• pp.1052-1056
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• 1996

The effects of β-CD, Me-β-CD, and biphenyl capped β-CD on 1H NMR spectra of mandelic acid 1, α-methylbenzylamine 2 and 2-phenylpropionic acid 3 were investigated. Enantiomeric recognition was observed for mandelic acid 1 by all the hosts used, for α-methylbenzylamine 2 by β-CD and Me-β-CD, and for 2-phenylpropionic acid 3 by Me-β-CD. In the presence of biphenyl-capped β-CD, ο-, m-, and p-protons of the phenyl groups of the guests are discriminated due to ring current of the capped biphenyl group. The splitting pattern of the phenyl protons indicates that the phenyl group of the guests is inserted into the β-CD cavity from the secondary hydroxyl side and positioned in close proximity to the capped biphenyl ring. The magnitude of the upfield shifts of H3 and H5 protons of β-CD upon binding of guests 1-3 is similar to that caused by ephedrine or pseudoephedrine, suggesting that the substitution at benzylic carbon atom has little effect on the depth of the insertion of the phenyl group into the β-CD cavity and stability of the inclusion complexes.

• The Journal of the Petrological Society of Korea
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• v.3 no.3
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• pp.196-219
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• 1994

Granulite complexes in northern (the Nangnim block), eastern (ther Kimchaek zone of the Macheonryong belt) and southern (separate windows among upper Proterozoic structure such as the Wonsan, Nampo and Haeju granulites) parts of the Northern Korea are studied. Multistage deformations, metamorphic and migmatitic events, and granite formations are recognized in these granulite complexes. Mineral thermobarometry and fluid inclusion investigationss are used to establish the P-T evolutionary trends during prograde and retrograde metamorphic events. The peak metamorphism of granulites is characterized by temperature near $800^{\circ}C$ and pressure near 5.5-6 kb. Retrograde evolution includes cooling at constant pressure or with variable pressure ranging up to 7-8 kb. This P-T change corresponds to the transition from high to moderate or low geothermal gradient. The subsequent cooling is ac-companied by significant decompression to 3-4 kb.

• Bulletin of the Korean Chemical Society
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• v.26 no.8
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• pp.1203-1208
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• 2005

A computational study based on molecular dynamics (MD) simulations was performed in order to explain the difference in aqueous solubilities of two flavonoid/$\beta$-cyclodextrin ($\beta$-CD) complexes, hesperetin/$\beta$-CD and naringenin/$\beta$-CD. The aqueous solubility of each flavonoid/$\beta$-CD complex could be characterized by complexwater interaction not by flavonoid-CD interaction. The radial distribution of water around each inclusion complex elucidated the difference of an experimentally observed solubility of each flavonoid/$\beta$-CD complex. The analyzed results suggested that a bulky hydrophobic moiety (-$OCH_3$) of B-ring of hesperetin nearby primary rim of $\beta$-CD was responsible for lower aqueous solubility of the hesperetin/$\beta$-CD complex.

• Analytical Science and Technology
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• v.20 no.5
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• pp.406-412
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• 2007

The formation of inclusion complexes between ${\beta}$-cyclodextrin and diethylenetriamine substituted-pyridine copper(II) perchlorate; [Cu(dien)(sub-py)] $(ClO_4)_2$, were studied by spectrophotometric methods. On account of charge-transfer band(MLCT) and $^2T_2{\rightarrow}^2E$, the two high peaks were observed as an inclusion complex for the [${\beta}$-CD]$[Cu(dien)(p-Cl-py)]^{2+}$ in the ultraviolet region of the spectrum. The ${\beta}$-CD and $[Cu(dien)(sub-py)]^{2+}$ ion formed a 1:1 complex, and the formation constants were decreased with the increasing temperatures, due to weak binding energy between ${\beta}$-CD and $[Cu(dien)(sub-py)]^{2+}$ ion. This reaction was controlled by enthalpy. In a correlation of the Hammett substituent constants and formation constants for the reaction, formation constants were increased by strong binding energy in the inclusion complexes when electron donating groups were substituted in pyridine ring.

• Bulletin of the Korean Chemical Society
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• v.30 no.12
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• pp.2927-2929
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• 2009

The hydricities of d$^6$ metal hydride complexes in aqueous solution were calculated by using density functional theoretical (DFT) calculations coupled with a Poisson-Boltzmann (PB) solvent model. Hydricity describes the hydride donor ability of the metal-hydrogen bond, which assists in the study of the mechanism of many catalytic processes and chemical reactions that involve transition metal hydrides. The calculation scheme produced hydricity values that were in good agreement with experimental estimation. The inclusion of a water molecule as a weakly bound ligand to five-coordinate metal complexes gave an improved correlation result.

• Bulletin of the Korean Chemical Society
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• v.20 no.12
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• pp.1475-1478
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• 1999

Ligand field calculations have been performed based on the data from the absorption and low temperature sharp-line excitation spectra of fac-Cr(gly)₃, fac-Cr(L-serine)₃ · 2H₂O and fac-Cr(L-leucine)₃·2H₂O. The optimized ligand field parameters for all complexes show that the carboxylate and the amino groups are moderate σ-donor. The values of $e_{{\pi}O}$ are typical of other complexes with carboxylate ligands. However, the π-interaction of carboxylic oxygen to the chromium in serinato complex is much weaker than that of other complexes. The inclusion of π-anisotropy is necessary to adequately explain the large doublet splittings.