• Journal of the Korean Society of Tobacco Science
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• v.4 no.1
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• pp.67-71
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• 1982

4, 8, 13-Duvatriene-1, 3-viols have been identified in the cuticular lipid of fresh Sohyang (aromatic cultivar) tobacco leaves. Their $\alpha, \beta$-isomers were directly separated by SE-54 glass capillary column and identified by mass spectrometry. Gas chromatographic analysis revealed that the duvatrienediols are major components in the culticular lipid of Nicotiana Tabacum.

• Journal of the Korean Wood Science and Technology
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• v.29 no.3
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• pp.99-103
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• 2001

Three flavan-3,4-diol derivatives were isolated from the heartwood of Robinia pseudoacacia and characterized by spectroscopic methods including $^1H$ and $^{13}C$ NMR and positive FAB-MS. The structures were identified as 4,4'-dimethoxy-, 4-ethoxy- and 4-ethoxy-4'-methoxy-2,3-trans-3,4-cis-(+)-leucorobinetinidin.

• Bulletin of the Korean Chemical Society
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• v.24 no.3
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• pp.295-298
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• 2003

α,β-Unsaturated aldehydes and ketones are regioselectively reduced to the corresponding allylic alcohols with /Dowex1-x8 system in THF at room temperature. This system is also efficient for the conversion of α-diketones and acyloins to the vicinal diols in refluxing THF.

• Bulletin of the Korean Chemical Society
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• v.8 no.6
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• pp.466-470
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• 1987

Di-2-pyridyl thionocarbonate, prepared from thiophosgene and 2-hydroxypyridine in the presence of triethylamine in dichloromethane, was found to be very effective for dehydration, dehydrosulfurization, and thiocarbonyl transfer reactions. Di-2-pyridyl thionocarbonate was successfully for the esterification of carboxylic acids, dehydration of aldoximes into nitriles, preparation of isothiocyanates from amines, and preparation of cyclic thionocarbonates from 1,2- and 1,3-diols.

• Bulletin of the Korean Chemical Society
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• v.16 no.4
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• pp.326-331
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• 1995

Poly(enaryloxynitriles) containing Schiff bases were prepared from p-bis(1-chloro-2,2-dicyanovinyl)benzene (2) and various aromatic diols having Schiff base moiety by interfacial polymerization. The chemical structure of the polymers was confirmed through synthesis of their corresponding model compounds. All the polymers were soluble in polar aprotic solvents and their brittle films were cast from DMF solution. They showed a large exotherm around 340 ℃ attributable to the chemical change of dicyanovinyl group. Especially, curing of azomethine group was observed to occur at 390 ℃ by differential scanning calorimetry. According to the thermogravimetric analyses, they exhibited excellent thermal stability with 60-90% residual weight at 500 ℃ in nitrogen.

• Bulletin of the Korean Chemical Society
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• v.17 no.4
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• pp.362-365
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• 1996

Carbonyl compounds 1, alkyl- and arylaldehydes and alkyl, aryl, benzylic, and cyclic ketones were converted to the corresponding 1,3-dioxolanes 2 and 1,3-dioxanes 4 with ethylene glycol and 2,2-dimethyl-1,3-propanediol in the presence of 1-3 mol% of 1-(p-substituted)benzyl-1,1-dimethyl-2-(p-substituted)-benzoyl hydrazinium hexafluoroantimonates 3 in high yields.

• Polymer(Korea)
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• v.29 no.3
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• pp.314-319
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• 2005

Four kinds of new aliphatic diols were synthesized by the ring opening reaction of glycolide with 1,4-butanediol, 1,6-hexanediol, 1,4-cyclohexanediol, or 1,4-cyclohexanedimethanol, a difunctional initiator, in the presence of stannous octoate catalyst. The resulting diols were melt-polymerized with succinic acid, adipic acid, or suberic acid at 170, 190, or $220^{circ}C$ to produce new sequentially ordered aliphatic polyesters and their corresponding polyesters with random structure. Their glass transition temperatures ($T_g$) ranged from -40 to $30^{circ}C$, The sequentially ordered polyesters prepared at $170^{cir}C$ had higher $T_g$ of 5 to $10^{circ}$ than the polyesters with rand()m structure produced at higher temperature. From in-vitro degradation test the sequentially ordered polyesters was shower in the rate of hydrolysis in a buffer solution than the polymers with random molecular structure.

• Natural Product Sciences
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• v.25 no.4
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• pp.348-353
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• 2019

Soluble epoxide hydrolases (sEH) are enzymes present in all living organisms, metabolize epoxy fatty acids to 1,2-diols. sEH in the metabolism of polyunsaturated fatty acids plays a key role in inflammation. In addition, the endogenous lipid mediators in cardiovascular disease are also broken down to diols by the action of sEH that enhanced cardiovascular protection. In this study, sEH inhibitory guided fractionation led to the isolation of five phenolic compounds trans-resveratrol (1), trans-piceatannol (2), sulfuretin (3), (+)-balanophonin (4), and cassigarol E (5) from the ethanol extract of the seeds of Passiflora edulis Sims cultivated in Vietnam. The chemical structures of isolated compounds were determined by the interpretation of NMR spectral data, mass spectra, and comparison with data from the literature. The soluble epoxide hydrolase (sEH) inhibitory activity of isolated compounds was evaluated. Among them, trans-piceatannol (2) showed the most potent inhibitory activity on sEH with an IC₅₀ value of 3.4 μM. This study marks the first time that sulfuretin (3) was isolated from Passiflora edulis as well as (+)-balanophonin (4), and cassigarol E (5) were isolated from Passiflora genus.

• KSBB Journal
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• v.22 no.3
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• pp.123-128
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• 2007

One drawback of conventional kinetic resolution of racemic epoxides by epoxide hydrolase (EH) is that the theoretical yield can never exceed 50%. This 50% limitation can be overcome by using enantioconvergent process, in which both enantiomers of the racemic epoxide are transformed via stereochemically matching pathways into a single enantiopure diol as the sole product in 100% theoretical yield. In order to make a single enantiopure vicinal diol, the two enantiomers of the racemic epoxide must be hydrolyzed with retention and inversion of configuration each other. The EHs should be enantio- and regiospecific at the same time. The enantioconvergent hydrolysis with EHs and relevant biotransformation for preparing enantiopure epoxides and vicinal diols with a high yield are reviewed.

• Journal of Adhesion and Interface
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• v.20 no.4
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• pp.140-145
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• 2019

In view of environmental considerations, the control of carbon dioxide (CO₂) and volatile organic compounds (VOCs) is one of important issues in the film and coating industries. Therefore, UV-curable system has been developed due to minimize emissions of VOCs and reduce CO₂ emission due to low energy consumption from fast curing. Also, biodegradable polymers economically are attractive because of environmental and economic concerns associated with huge waste plastics. In this study, UV-curable polyurethane acrylates with different compositions of biodegradable polylactide (PLA) diol and poly(ethylene glycol) as diols were synthesized and curing reaction of their end-capped acrylates was performed by UV exposure. Tensile strength, elongation, and Tg of the UV-cured polyurethane acrylates increased with PLA diol content in the diol while their hydrophilicity and thermal stability increased with the PEG content. These results indicated a property of UV-cured polyurethane acrylates could be controlled by environment-friendly diols.