• 한국응용과학기술학회지
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• 제5권1호
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• pp.41-51
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• 1988

Aliphatic aldehyde polyoxyethylene glycol acetals were synthesised through the reaction of aliphatic aldehydes such as caproic aldehyde, capryl aldehyde, capric aldehyde and lauric aldehyde with excess diethylene glycol, triethylene glycol and tetraethylene glycol, respectively. The acetal formation, in which water was azeotropically distilled by adding benzene to the reaction system, was gained a good yield of acetal type compounds. This reaction is found pseudo first order reaction at various temperatures such 70, 80, 90 and $97^{\circ}C$. Also these activation energies of reaction of acetal type products such as caproic aldehyde diethylene glycol acetal, capryl aldehyde diethylene glycol acetal, capric aldehyde diethylene glycol acetal, lauric aldehyde diethylene glycol acetal, caproic aldehyde triethylene glycol acetal and caproic aldehyde tetraethylene acetal were 17.3, 19.6, 21.2, 21.6, 15.5 and 14.7 Kcal/mole.

• Toxicological Research
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• 제14권2호
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• pp.157-161
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• 1998

The mechanism of active aldehyde-induced liver disease and the enzymatic basis of detoxification were investigated using normal rat liver cell, Ac2F. Aliphatic alcohols including l-decyl alcohol, l-nonanol, l-heptanol, l-hexanol, l-propanol and allyl alcohol exerted a dose- and time-de-pendent toxicity to Ac2F cells. The extent of their toxicities in buthionine sulfoximine (inhibitor of glutathione synthesis) pretreated cells was greater than in pargyline (inhibitor of aldehyde dehydrogenase, ALDH). On the other hand, the toxicity of these alcohols were not affected by 4-methylpyrazole (inhibitor of alcohol dehydrogenase, ADH). These results suggest that the contents of glutathione (GSH) seems to be very important in protecting the cells from toxicants such as aliphatic alcohols.

• Bulletin of the Korean Chemical Society
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• 제7권4호
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• pp.323-325
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• 1986

• 대한화학회지
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• 제52권5호
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• pp.511-514
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• 2008

• 생약학회지
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• 제40권4호
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• pp.326-333
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• 2009

Fourteen compounds were isolated from the 70% ethanol extract of Lonicera Caulis (Caprifoliaceae) and their structures were identified as seven aliphatic compounds [long-chain alcohols (1, 2), trilinolein (3), hexacosanol (4), fatty acids (6), 9,12,13-trihydroxyoctadeca-10(E),15(Z)-dienoic acid (10), and pinellic acid (11)] and seven phenolics [bis(2-ethylhexyl) phthalate (dioctylphthalate, DOP) (5), coniferaldehyde (7), caffeic acid docosanoyl ester (8), caffeic acid (9), coniferyl aldehyde 4-O-glucoside (12), linarin (13), and coniferin (14)]. The chemical structures of these compounds were identified on the basis of spectroscopic methods and comparison with literature values. All the compounds except for caffeic acid (9) were isolated from this plant parts for the first time.

• 한국식품영양학회지
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• 제26권2호
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• pp.287-294
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• 2013

This study was investigated the chemical composition from Syneilesis palmata essential oil and the tendency of variation of the sesquiterpene compounds according to the harvesting time. The essential oils obtained by hydro distillation from the aerial parts of Syneilesis palmata were analyzed by GC and GC-MS. Ninety-eight compounds consisting of 9 aliphatic hydrocarbons, 17 sesquiterpene hydrocarbons, 11 aliphatic aldehydes, 1 terpene aldehyde, 8 aliphatic alcohols, 4 monoterpene alcohols, 16 sesquiterpene alcohols, 3 diterpene alcohols, 6 ketones, 11 esters, 8 oxides and epoxides, 3 acids and 1 miscellaneous one were identified from the oil. Spathulenol (22.33%) was the most abundant compound, followed by ${\beta}$- caryophyllene (6.23%), germacrene D (5.57%), longipinane (4.10%), and epiglobulol (3.65%). The volatile composition of Syneilesis palmata was characterized by higher contents of sesquiterpene compounds, especially sesquiterpene alcohols. The total content of 13 sesquiterpene compounds was decreased significantly from 2010 to 2012. ${\alpha}$-Caryophyllene, ${\beta}$-bisabolene, elemol, germacrene D, ${\beta}$-zingiberene, longipinane, and ${\beta}$-caryophyllene alcohol contents decreased, while ${\beta}$-bisabolol content increased during 3 years. The ecological responses to recent climate change may be influenced in the chemical components of natural plant terpenoids.

• Bulletin of the Korean Chemical Society
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• 제10권1호
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• pp.75-80
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• 1989

The approximate rates and stoichiometry of the reaction of excess potassium 9-sec-amyl-9-boratabicylco[3.3.1]nonane (K 9-sec-Am-9-BBNH) with selected organic compounds containing representative functional goups under standardized conditions (tetrahydrofuran, $0^{\circ}C)$ were examined in order to explore the reducing characteristics of the reagent for selective reductions. The reagent readily reduces aldehydes, ketones, acid chlorides and epoxides to the corresponding alcohols. However, carboxylic acid, aliphatic nitriles, t-amides, and some sulfur compounds show very little reactivity or no reactivity to this reagent. The most interesting feature of the reagent is that aromatic nitriles are reduced moderately to the corresponding aldehyde stage, wheras aliphatic nitriles are inert. In addition, the reagent shows a high stereoselectivity toward cyclic ketones at $0^{\circ}C$ and - $25^{\circ}C.$ The selectivity exhibited at $0^{\circ}C$ is comparable to that by lithium trisiamylborohydride at that temperature.

• 한국환경농학회지
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• 제13권2호
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• pp.191-198
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• 1994

유기티탄 화합물들은 카르보닐 화합물들과의 첨가반응에서 알킬리튬이나 Grignard시약 같은 고전적인 유기금속화합물에 비하여 화학적, 입체화학적 선택성이 뛰어남은 이미 잘 알려져 있다. 하지만 탄소-탄소 결합에 이용된 유기티탄 화합물의 유기잔기는 방향족 중 일부와 aliphatic 중 methyl, allyl기 등에 한정되었다. 본 실험에서는 방향족 중 thiophene의 티탄화합물인 2-thiophenyl triisopropoxytitanium을 최초로 합성하고, 이것의 카르보닐 화합물과의 반응성을 실험하였다. 이 화합물은 알데히드와 케톤에 높은 수율(평균수율 94% 이상)로 첨가반응하고, 특히 알데히드와 케톤 경쟁반응에서 알데히드에만 그리고 케톤과 에스테르 작용기 사이에서는 케톤에만 화학 선택적으로 첨가 반응하였다. 그러므로 알데히드와 케톤기가 동시에 존재하는 화합물에서 케톤기를 보호시키지 않고 thiophene기를 직접 알데히드에 첨가할 수 있고, 케톤과 에스테르작용기가 있는 화합물에서는 케톤에 직접 첨가할 수 있는 새로운 방법이 개발되었다고 하겠다.

• 대한화학회지
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• 제58권5호
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• pp.445-449
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• 2014

A convenient and efficient method has been developed for the one-pot synthesis of dihydropyrimidinones (DHPMs) compounds. Dihydropyrimidinone derivatives were synthesized in good yields using ethyl acetoacetate, aldehyde (aromatic and aliphatic) and urea or thiourea in the presence of ZnO nanoparticles as a catalyst in $H_2O$ as solvent at $80^{\circ}C$. This green chemistry procedure applied to the Biginelli reaction using ZnO nanoparticles as catalyst and illustrated as a rapid preparation of DHPMs in water as solvent. The products were identified by physical data (mp) by comparison with those reported in the literatures.

• Carbon letters
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• 제2권3_4호
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• pp.170-175
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• 2001

A petroleum-based isotropic pitch fiber spun by melt-blown method was oxidized in air flow at various conditions. The oxidized pitch fiber obtained was tested for its infusibility and its elemental composition during the process of stabilization. The structural changes were traced by using solvent solubility, FT-IR spectroscopy, and elemental analysis. The samples showed a gradual increase in weight with increasing the oxidization temperature. The weight gain of sample oxidized at $320^{\circ}C$ for 10 min was about 4.5%. The concentration of the pyridine and toluene soluble fraction decreased with an increase in stabilization temperatures. The oxygen uptaken in the stabilization process converted aliphatic side chains into the carbonyl groups. As stabilization proceeded, the more ether and carboxylic acid groups were formed through the oxidations of aldehyde and primary alcohol, and then the carboxylic acid was dehydrated to be aromatic anhydride.