• Journal of Microbiology and Biotechnology
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• v.27 no.6
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• pp.1065-1070
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• 2017

This study aimed to examine the anti-candidal efficacy of a novel ketone derivative isolated from Diaporthe sp. ED2, an endophytic fungus residing in medicinal herb Orthosiphon stamieus Benth. The ethyl acetate extract of the fungal culture was separated by open column and reverse phase high-performance liquid chromatography (HPLC). The eluent at retention time 5.64 min in the HPLC system was the only compound that exhibited anti-candidal activity on Kirby-Bauer assay. The structure of the compound was also elucidated by nuclear magnetic resonance and spectroscopy techniques. The purified anti-candidal compound was obtained as a colorless solid and characterized as 3-hydroxy-5-methoxyhex-5-ene-2,4-dione. On broth microdilution assay, the compound also exhibited fungicidal activity on a clinical strain of Candida albicans at a minimal inhibitory concentration of $3.1{\mu}g/ml$. The killing kinetic analysis also revealed that the compound was fungicidal against C. albicans in a concentration- and time-dependent manner. The compound was heat-stable up to $70^{\circ}C$, but its anti-candidal activity was affected at pH 2.

• Bulletin of the Korean Chemical Society
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• v.26 no.9
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• pp.1366-1368
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• 2005

The first synthesis of a 4'-branched carbocyclic C-nucleoside 11 was achieved via the key intermediate 6, which was prepared using Knovenagel type condensation from ketone derivative 4.

• 한국정보디스플레이학회:학술대회논문집
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• 2004.08a
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• pp.281-284
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• 2004

Photo-induced memory effect of an organic light-emitting diode(OLED) composed of a hydrazone-derivative(DBAH) dispersed in bis-phenol-A type polycarbonate polymer(PCA) in the presence of thio-Michler's ketone, was investigated by the measuring of the current density and luminance at the various conditions. After the light exposure, the current of the OLED was decreased approximately one order, and the luminance of the OLED also decresed. This memory effct was erasable by heating the OLED to the temperature higher than the glass transition temperature(Tg). As shown in this result, we found the memory effect was erased by heating and returned to its original state in the hole injecting layer(HIL) of the OLED. A series of these phenomena was suggested the possibility of the application to the imaging plate.

• Archives of Pharmacal Research
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• v.1 no.1
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• pp.27-32
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• 1978

A procedure of $^3H$-radio labeling synthesis for the dammarane triterpene glycosides of Korean ginseng was established by using the ginsenoside $Rg_1$ as starting material. The protons in $C-{11}$ and $C_{13}$ of the aglycone moiety of the glycoside were exchanged with tritium by keto-enol tautomerization of 12-keto-ginsenoside $Rg_1$ which was prepared by partial acetylation, Sarett oxidation and saponification, producing nona-acetate, nonaside $Rg_1$. The acety1-ketone and 12-keto-derivative of ginsenotritated ketone was reduced by metallic sodium and isoproponol to produce the end product $^3H$-ginsenoside $Rg_1$ with 3% radio-chemical recovery in one experiment.

• YAKHAK HOEJI
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• v.34 no.4
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• pp.219-223
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• 1990

7,8-Dihydro-6,11-dihydroxy-9(10H)benzo(b)phenazinone was prepared from 1,2,3,4-tetra-hydrophenazine as a potential isostere of anthracyclinone. The attempts to functionalize at $C_9$ were not successful due to the unstability of the above ketone.

• Proceedings of the Membrane Society of Korea Conference
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• 2003.07a
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• pp.57-59
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• 2003

Molecular dynamics simulations have been performed on $\beta$-cyclodextrins octyl-derivative (b-CD) encapsulated into a polymer matrix of glassy poly(ether ether ketone) (PEEK-WC) material to investigate the effects of the complexation of p-nitrophenilacetate and naringin molecules with the aim to study the recognition properties of b-CD.

• YAKHAK HOEJI
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• v.45 no.4
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• pp.407-412
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• 2001

A $Ca^{2+}$_dependent PLA$_2$activity termed rPLA$_2$, was detected in the cytosol of bovine red blood cells (RBCs). The rPLA$_2$was characterized as a similar form to Group IV cPLA$_2$, but different in several column chromatographic profiles including an anion exchange column. To examine whether this rPLA$_2$is different from the well characterized cPLA$_2$, a quinone derivative, BJ50, was developed and tested for the inhibitory effect on the two PLA$_2$enzymes. The rPLA$_2$activity was inhibited by a quinone derivative (BJ50) with ID$_{50}$ of 20 $\mu$M., but had no effect on the cPLA$_2$, suggesting that rPLA$_2$may be a novel type of cytosolic PLA$_2$in RBCs.s.s.

• Bulletin of the Korean Chemical Society
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• v.35 no.12
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• pp.3502-3508
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• 2014

The first synthetic route to 5'-norcarbocyclic C-nucleoside [7-oxa-7,9-dideazadenosine (furo[3,2-d]pyrimidine) and 9-deazaadenosine (pyrrolo[3,2-d]pyrimidine)] phosphonic acids from commercially available 1,3-dihydroxy cyclopentane was described. The key C-C bond formation from sugar to base precursor was performed using Knoevenagel-type condensation from a ketone derivative. Synthesized C-nucleoside phosphonic acids were tested for anti-HIV activity as well as anti-leukemic activity. Compound 26 showed significant anti-leukemic activity.

• YAKHAK HOEJI
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• v.48 no.1
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• pp.88-92
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• 2004

In this study; a series of 2',4'-doubly branched carbocyclic nucleosides (8,9,10) were synthesized from simple acyclic ketone derivative as starting material. The installation of the 4'-quaternary carbon needed was carried out using a 〔3,3〕-sigmatropic rearrangement. In addition, the introduction of a methyl group in the 2'-position was accomplished by Grig-nard reaction. Bis-vinyl was successfully cyclized using a Grubbs' catalyst II. The natural bases (adenine, cytosine, uracil) were efficiently coupled with the use of a Pd(0) catalyst. Although all the synthesized compounds were assayed against several viruses, only cytosine analogue 9 showed weak antiviral viral activity (EC$_{50}$=45.4 $\mu$M) against CoxB3 virus.s.

• Bulletin of the Korean Chemical Society
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• v.17 no.1
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• pp.50-55
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• 1996

Reaction of carbonyl compounds with diisopinocampheylhaloboranes (Ipc2BX,X=Cl, Br, I) was investigated in detail in order to establish their usefulness as selective reducing agents. The reagents reduced aldehydes and ketones to the corresponding alcohols. The reactivities are in the order of Ipc2BCl Ipc2BBr>Ipc2BI.The reagents also reduced ${\alpha}{\beta}-unsaturated$, aldehydes and ketones to the corresponding allylic alcohols without any detectable 1,4-reduction. Especially, the chloro derivative nicely achieved the selective reduction of aldehyde or ketone groups in the presence of many other functional groups. The most remarkable result of this investigation is that aldehydes and ketones can be selectively reduced in the presence of acid chlorides.