• Bulletin of the Korean Chemical Society
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• v.16 no.6
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• pp.528-533
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• 1995

Metallic iridium and rhodium powders prepared from the reactions of [M(COD)(PhCN)2]ClO4 (M=Ir(1), Rh(2); COD=1,5-cyclooctadiene) with hydrogen at room temperature in methylene chloride show catalytic activities for hydrogenation of arenes at room temperature under atmospheric pressure of hydrogen. Most substituents (CH3, COOH, NO2, CH2OH, CHO, OPh, OCH3, C=C, halogens and CH2Cl) on aromatic ring suppress the rate of the hydrogenation of the aromatic ring while the aromatic ring hydrogenation of phenol and 1,4-dihydroxobenzene is faster than that of benzene over these metallic powders. Hydrogenation of benzoic acid occurs only at the aromatic ring leaving the COOH group intact over iridium metal powders while benzoic acid is not hydrogenated at all over rhodium metal powders. Carbonyl, nitro, acetylenic and olefinic groups on an aromatic ring are hydrogenated prior to the aromatic ring hydrogenation. Hydrogenolysis of OH groups of phenol, benzyl alcohol and 1,4-dihydroxobenzene, and hydrodehalogenation of halobenzenes, benzyl halides and cinnamyl chloride also occur along with the hydrogenation of aromatic ring.

• Archives of Pharmacal Research
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• v.28 no.7
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• pp.756-760
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• 2005

Polyene macrolide amphotericin B (AmB) is the drug of choice for the treatment of disseminated fungal infections. However, because of its pronounced side effects, the drug has limited applicability. There are few interesting reports, which state that co-administration of the drug with homo-peptide of polyaspartic acid reduces the side effects of the drug. In our present study, an approach has been made to systematically synthesize low molecular weight heteropeptides consisting of L-aspartic acid and its derivative. It was hypothesized that such heteropeptides will reduce the toxic side effects of the drug by facile hydrophobic binding between the polymer and the drug. We have employed the strategy of solid phase peptide synthesis (SPPS) to synthesize low molecular weight hetero-peptides by using L-aspartic acid and benzyl-L-aspartic acid to induce the hydrophobic binding between the peptide and the drug. In future, the proposed methodology can be employed to tailor other polypeptides substituted with benzyl groups to reduce the nephrotoxicity of AmB.

• Bulletin of the Korean Chemical Society
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• v.13 no.4
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• pp.359-361
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• 1992

• Applied Chemistry for Engineering
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• v.26 no.3
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• pp.372-376
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• 2015

6-MQCC (Cr(VI)-6-methylquinoline) complex was synthesized by the reaction of 6-methylquinoline with chromium(VI) trioxide in 6 M HCl. The structure was characterized using IR (Infrared Spectroscopy) and ICP (Inductively Coupled Plasma) analysis. The oxidation of benzyl alcohol using 6-MQCC in various solvents showed that the reactivity increased with the increase of the dielectric constant, in descending order of DMF > acetone > chloroform > cyclohexene. In the presence of DMF solvent with acidic catalyst such as sulfuric acid ($H_2SO_4$), 6-MQCC oxidized benzyl alcohol (H) and its derivatives ($p-OCH_3$, $m-CH_3$, $m-OCH_3$, m-Cl, $m-NO_2$) were effectively oxidized. Electron-donating substituents accelerated the reaction rate, whereas electron acceptor groups retarded the reaction rate. The Hammett reaction constant (${\rho}$) was -0.69 (308 K). The observed experimental data was used to rationalize the fact that the hydride ion transfer occurred at the rate-determining step.

• Applied Chemistry for Engineering
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• v.16 no.1
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• pp.153-157
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• 2005

4-(Dimethylamino)pyridinium dichromate was synthesized by the reaction of 4-(dimethylamino)pyridine with chromium(VI)trioxide in $H_2O$, and characterized by IR, EA and ICP. The oxidation of benzyl alcohol using 4-(dimethylamino)pyridinium dichromate in various solvents showed that the reactivity increased with the increase of the dielectric constant, in the order: cyclohexen < chloroform < acetone < N,N-dimethylformamide. In the presence of hydrochloric acid(HCl), 4-(dimethylamino)pyridinium dichromate oxidized benzyl alcohol and its derivatives ($p-CH_3$, H, m-Br, $m-NO_2$) smoothly in N,N-dimethylformamide. Electron-donating substituents accelerated the reaction, whereas electron-withdrawing groups retarded the reaction. The Hammett reaction constant($\rho$) was -0.70 at 303K. The observed experimental data have been rationalized as follows: the proton transfer occurs after the prior formation of a chromate ester in the rate-determining step.

• Membrane Journal
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• v.25 no.4
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• pp.310-319
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• 2015

Three kinds of anion-exchangeable functional groups with different hydrocarbon molecular structures were introduced to vinyl benzyl chloride-based membrane to understand the effect of attached function in anion-exchange membrane. Trimethylamine (TMA) as an aliphatic fuction, N-methylpiperidine (MP) as an alicyclic fuction and pyridine (Py) as an aromatic function were introduced by amination. The respective reactivity was observed by the trace of membrane resistance( MER)/ion exchange capacity (IEC) and the increasing order of reactivity was Py < MP < TMA. Meanwhile, SEM photograph showed the attached Py ion-exchange membrane was the most homogenous and compact structure in the study. In electrochemical properties, the attached Py ion-exchange membrane showed the MER ($5.0{\Omega}{\cdot}cm^2$ >, in 0.5 mol/L NaCl), comparable to those of commercial membrane (AMX). All results showed that the resonance structure of attached functional group might contribute to the preparation of homogenous anion-exchange membrane.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.13 no.1
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• pp.462-469
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• 2012

Cr(VI)-4,4'-bipyridine complex(4,4'-bipyridinium dichromate) was synthesized by the reaction of 4,4'-bipyridine with chromium trioxide in H2O, and characterized by IR, ICP. The oxidation of benzyl alcohol using 4,4'-bipyridinium dichromate in various solvents showed that the reactivity increased with the increase of the dielectric constant(${\varepsilon}$), in the order: cyclohexene$CH_3$, H, m-Br, m-$NO_2$) smoothly in N,N'-dimethylformamide. Electron-donating substituents accelerated the reaction, whereas electron acceptor groups retarded the reaction. The Hammett reaction constant(${\rho}$) was -0.63(303K). The observed experimental data have been rationalized as follows; the proton transfer occurs after the prior formation of a chromate ester in the rate determining step.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.14 no.11
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• pp.6039-6046
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• 2013

Cr(VI)-heterocyclic complex[Cr(VI)-2-methylpyrazine] was synthesized by the reaction between of heterocyclic compound(2-methylpyrazine) and chromium trioxide, and characterized by IR and ICP analysis. The oxidation of benzyl alcohol using Cr(VI)-2-methylpyrazine in various solvents showed that the reactivity increased with the increase of the dielectric constant(${\varepsilon}$), in the order : cyclohexene${\rho}$) was Cr(VI)-2-methylpyrazine= -0.65(308K). The observed experimental data have been ratiolized. The hydride ion transfer causes the prior formation of a chromate ester in the rate-determining step.

• Applied Chemistry for Engineering
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• v.25 no.6
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• pp.648-653
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• 2014

Cr(VI)-heterocyclic complex (2,4'-bipyridinium chlorochromate) was synthesized by the reaction between heterocyclic compound(2,4'-bipyridine) and chromium trioxide, and characterized by IR and ICP analysis. The oxidation of benzyl alcohol using 2,4'-bipyridinium chlorochromate in various solvents showed that the reactivity increased with the increase of the dielectric constant (${\varepsilon}$), in the order : N,N-dimet-hylformamide (DMF) > acetone > chloroform > cyclohexene. In the presence of DMF solvent with acidic catalyst such as hydrochloric acid (HCl solution), 2,4'-bipyridinium chlorochromate oxidized benzyl alcohol (H) and its derivatives (p-$CH_3$, m-Br, m-$NO_2$). Electron-donating substituents accelerated the reaction rate, whereas electron acceptor groups retarded the reaction rate. The Hammett reaction constant (${\rho}$) was -0.67 (303 K). The observed experimental data have been rationalize the proton transfer occurred followed the formation of a chromate ester in the rate-determining step.

• Journal of Environmental Health Sciences
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• v.30 no.2
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• pp.71-78
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• 2004

This study was performed to evaluate developmental and estrogenic activity of bisphenol A (BPA) and butyl benzyl phthalate (BBP) to the second generation of Sprague-Dawley rats ingested during gestational or lactational periods. Rats were given BPA 20$\mu\textrm{g}$/kg BBP 100mg/kg of pregnancy or lactation periods. Maternal body weight and neonatal body weight were recorded. The rats were sacrificed on day 21 after birth. Reproductive organs of dam and neonate were utilized for receptor binding assay. The plasma concentrations of BPA and MBep, one of the major metabolites of BBP were analyzed with HPLC. The co-administration of BPA and BBP induced slow weight gain compared with single administration in dams. Also, such mixture induced low neonatal body weights in next generation. The dams treated with BPA and BBP during lactational periods showed significant organ weight changes in liver and spleen. The dams exposed during lactational periods showed significant organ weight changes not only in liver and spleen but also in kidney, uterus and ovary. The F1 female rats exposed during lactation periods showed significant organ weight changes in liver, spleen, ovary. The F1 male rats showed significant organ weight changes in liver, kidney, epididymis, vesicular glands, prostate. However, no clear synergistic effects of BPA and BBP were noted. There was no significantly different ER$\alpha$ expression pattern between control and treated groups. However, ER$\alpha$ expression were increased in F1 male testis and female uterus. PI male showed distinct ER$\alpha$ expression, especially in the group of lactational combined exposure. Synergistic ER$\alpha$ expression was found by combined treatment of BPA and BBP. We could not find any evidences of synergistic effects on BPA and/or BBP combined administration on dams and their fetuses, except in ER$\alpha$ expression of F1 male.