• Bulletin of the Korean Chemical Society
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• v.30 no.2
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• pp.355-362
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• 2009

The chemical modification of multi-wall carbon nanotubes (MWNTs) is an emerging area in material science. In the present study, hydroxyl functionalized oxovanadium(IV) Schiff-base; N,N'-bis(4-hydroxysalicylidene)-ethylene-1, 2-diamineoxovanadium(IV), [VO($(OH)_2$-salen)]; has been covalently anchored on modified MWNTs. The new modified MWNTs ([VO($(OH)_2$-salen)]-MWNTs]) have been characterized by transmission electron microscopy (TEM), X-ray diffraction (XRD), X-ray photoelectron (XPS), UV-Vis, Diffuse reflectance (DRS), FT-IR spectroscopy and elemental analysis. The analytical data indicated a composition corresponding to the mononuclear complex of tetradentate Schiff-base ligand. The characterization of the data showed the absence of extraneous complex, retention of MWNTs and covalently anchored on modified MWNTs. Liquid-phase oxidation of cyclohexane with $H_2O_2$ to a mixture of cyclohexanone, cyclohexanol and cyclohexane-1,2-diol in $CH_3$CN have been reported using oxovanadium(IV) Schiff-base complex covalently anchored on modified MWNTs as catalysts. This catalyst is more selective toward cyclohexanol formation.

• The Korean Journal of Food And Nutrition
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• v.35 no.3
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• pp.185-192
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• 2022

This study investigated the volatile flavor components of the essential oil from Chrysanthemum coronarium var. spatiosumBailey. The essential oil obtained from the aerial parts of the plant by the hydrodistillation extraction method was analyzed by gas chromatography and gas chromatography-mass spectrometry. One hundred and one (99.11%) volatile flavor components were identified in the essential oil from the Chrysanthemum coronarium var. spatiosum Bailey. The major compounds were hexanedioic acid, bis(2-ethylhexyl) ester (12.45%), 6.10.14-trimethyl-2-pentadecanone (7.94%), 1-(phenylethynyl)-1-cyclohexanol (6.34%), α-farnesene (5.55%), phytol (4.99%), and α-caryophyllene (4.39%). When the volatile flavor components of Chrysanthemum coronarium var. spatiosum Bailey were classified by functional group, the content was high in the order of hydrocarbons, alcohols, esters, ketones, aldehydes, and phthalides. Sesquiterpene hydrocarbons were the most common hydrocarbons, mainly due to α-farnesene and α-caryophyllene. Among the alcohols, the content of aliphatic alcohols was significantly higher, mainly due to 1-(phenylethnyl)-1-cyclohexanol (6.34%) and phytol (4.99%). The analysis of the volatile flavor components of Chrysanthemum coronarium var. spatiosum Bailey in this study will provide useful information to consumers when purchasing food and to industries using fragrance ingredients.

• Mass Spectrometry Letters
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• v.14 no.1
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• pp.9-23
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• 2023

Plants are able to produce a large number of diverse bioactive compounds. Solvent extraction is used for isolation of plant metabolites. The extract yield for plant metabolite extraction strongly depends on the nature of solvent. A review showed the methanol can yield more bioactive compounds. Drying of the sample material is also important for the extraction of plant material. The present study was carried out to analyze the phytocomponents of 5 different latex producing plants. The plants like Calotropis gigantea, Carica papaya, Nerium oleander, Ficus benghalensis and Plumeria alba leaves and latex. The GC-MS analysis of the metabolites revealed phytocomponents. Calotropis gigantea leaves showed 14 compounds and latex produced 5 compounds out of this 4,4,6A,6B,8A,11,11,14B-Octamethyl-1,4,4A,5,6,6A,6B,7,8,8A,9,10,11,12,12A,14,14A,14B-Octadeca-hydro-2 and 2R- Acetoxymethyl-1,3,3-trimethyl-4T-(3-Methyl-2-Buten-1-Yl)-1T-Cyclohexanol compound was present in both latex and leaf extraction. Beta. -carotene compound was present in both latex and leaf of Carica papaya. It was observed that Ficus benghalensis contained 2R-Acetoxymethyl-1,3,3-trimethyl-4T-(3-Methyl-2-Buten-1-Yl)-1T-Cyclohexanol was same in latex and leaf extraction.

• Biomedical Science Letters
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• v.12 no.3
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• pp.241-247
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• 2006

To evaluate an effect of pathological liver damage on the cyclohexane (CH) metabolism, rats were pretreated with 50% carbon tetrachloride $(CCl_4)$ dissolved in olive oil (0.1ml/100g body weight) 10 or 17 times intraperitoneally at intervals of every other day. To these liver damaged animals, CH (a single dose of 1.56g/kg body weight, i.p.) was administered at 48hr after the last injection of $CCl_4$. The CH metabolites; cyclohexanol (CH-ol), cyclohexane-l,2-diol (CH-l,2-diol) and cyclohexane-l,4-diol (CH-l,4-diol) and cyclohexanone (CH-one) were detected in the urine of CH treated rats. After CH treatment, the serum levels of CH-ol and CH-one were remarkably increased at 4 hr and then decreased at 8hr in normal group. Whereas in liver damaged rats, these CH metabolites were higher at 8hr than at 4hr. The excretion rate of CH metabolites trom serum into urine was more decreased in liver damaged animals than normal group, with the levels of excretion rate being lower in $CCl_4$ 17 times injected animals than 10 times injected ones. It was interesting that the urinary concentration of CH metabolites was generally more increased in liver damaged animals than normal ones, and the increasing rate was higher in $CCl_4$ 17 times injected rats than 10 times injected ones. Taken all together, it is assumed that reduced urinary excretion rate of CH metabolites in liver damaged rats might be resulted from deteriorated hepatic and renal blood flow, and an increased urinary excretion amount of CH metabolites in liver damaged rats might be caused by reduced expiration amount of the metabolites due to lung damage.

• Journal of the Korean Chemical Society
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• v.22 no.1
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• pp.37-44
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• 1978

The effect of lithium chloride on the borane reduction of organic compounds was studied for three ketones, seven acid derivatives, three epoxides and cyclohexene in tetrahydrofuran at $0^{\circ}$. When compared with borane itself, borane-lithium chloride system enhanced the rates of reductions markedly of 2-heptanone, acetophenone, benzoyl chloride, phthalic anhydride, and three epoxides, whereas the reductions of benzophenone, four esters and cyclohexene showed little or no effect. $BH_3$-LiCl (1 : 0.1) reduced styrene oxide in 2 hr at $0^{\circ}$ to give 94.2 % yield of alcohols, 1-to 2-phenylethanol ratio being 60.8 to 39.2. And in the reduction of cyclohexene oxide, $BH_3$-LiCl (1 : 0.1) gave a quantitative yield of cyclohexanol in 2 hr at $0{\circ}$, however $BH_3$-LiCl (1 : 1) gave 58 % cyclohexanol and 42 % 2-chlorocyclohexanol. In the reduction of cyclohexene oxide, lithium nitrate showed no rate enhancement even when the salt was added in large excess. A formation of lithium chloroborohydride in the$BH_3$-LiCl system is suggested.

• Journal of the Korean Chemical Society
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• v.19 no.5
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• pp.355-359
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• 1975

Reduction of epoxy ketones with zinc borohydride proceeds selectively to the corresponding epoxy alcohols in good yields. Thus we obtained 3,4-epoxy-4-methyl-2-pentanol($79.8{\%}$), trans-isophorol oxide ($89.5{\%}$), trans-2-benzal-cyclohexanol oxide ($84.1{\%}$) and trans-chalcol oxide ($97.9{\%}$, crude) from the corresponding epoxy ketones.

• The Korean Journal of Food And Nutrition
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• v.11 no.5
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• pp.493-498
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• 1998

An attempt was in this to analyzer volatile flavor components of sancho(Zanthoxylum schinfolium). Essential oils in sancho tree and fruit isolated by a simulataneous steam distillation (SDE) methods using n-pentane/diethyl ether as solvent. A total of 57 and 44 components were identified by gas chromatography(GC) and combined gas chromatography spectrometry (GC-MS), respectively. Granyl acetate(29.23%) geraniol (6.80%, p-isopropyl-2-chclohexenone(5.53%), phellandral (4.10%) in sancho fruit and 4, 6, 6-trimethyl-bicyclo(7.47%), T-carvelo(4.60%, ${\alpha}$-cypernone(3.58%) in sancho tree were found to be major volatile flavor. 22 compnents including myrcene, limonene, 1, 8-cinol in sancho fruit and 10 components including 4-(1-methylethyl)-cyclohexanol, methyl undecyl ketone in sancho tree were identified. The contents of unsaturated fatty acids of palmitic acid(24.34%), myristic acid(3,68%) in sancho tree was higher than that of the sancho fruit.

• Bulletin of the Korean Chemical Society
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• v.20 no.7
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• pp.781-785
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• 1999

Ferrisilicates with MFI type structure were hydrothermally synthesized. The structural environments of iron in the ferrisilicates were characterized by XRD, SEM, IR, EPR, and ammonia-TPD. It has been shown that pH of the final gel mixture during the synthesis affects the crystal size, morphology, chemical composition and catalyticactivity. The results of the lattice parameters, IR, and EPR indicate the existence of a framework iron and the content of framework iron depends on pH of the synthesis gel. Finally, the catalytic activity of these zeolites was examined for the cyclohexane oxidation to cyclohexanol and cyclohexanone in the liquid phase. The conversion of this reaction was increased with increasing iron content of the framework lattice positions.

• Bulletin of the Korean Chemical Society
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• v.19 no.11
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• pp.1233-1238
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• 1998

Transglycosylation reactions among methyl 2,3,4,6-tetra-O-methyl-D-glycopyranosides and isomeric butyl alcohols or cyclohexanol took place in the presence of trimethylsilyl trifluoromethanesulfonate (TMSOTf) in dichloromethane. The extent of the reaction after 1 h and 24 h from mixing was determined by gas chromatography (GC). Anomerization of the substrate took place during the course of transglycosylation, which favors α anomer regardless of the anomeric configurations of the starting glycosides. Transglycosylation also favors the a anomer regardless of the steric bulkiness of the alcohol. tert-Butyl alcohol did not give any transglycosylation, suggesting the steric hindrance of approaching the bulky alcohol to the oxonium intermediate. A mechanism for the transglycosylation have been proposed.

• Bulletin of the Korean Chemical Society
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• v.18 no.12
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• pp.1269-1273
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• 1997

The system which employs iron, palladium, molecular oxygen and hydrogen as a model mono-oxygenase, has been investigated to develop a new method for selective cyclohexane oxidation uner mild conditions. This system provides much higher yield and selectivity for the formation of cyclohexanol and cyclohexanone compared to that of the existing industrial method. When the catalytic system, FeCl2-Pd/alumina, was employed, the oxidation system required acetone as a solvent to be efficient and acidifying the solvent by a little addition of acetic acid or HCl made the system more efficient. The Pd catalyst was recyclable without a significant deactivation but the recycling of ferrous chloride showed the decrease in the activity. On the other hand, the heterogeneous catalytic system, Pd/Fe2O3 could be recovered easily and reused after drying treatment.