• Bulletin of the Korean Chemical Society
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• v.28 no.11
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• pp.1910-1916
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• 2007

Analyzed are recent advances in design of novel boronared conjugates of synthetic and natural porphyrins and chlorins. These compounds showed high efficacy as cytotoxic agents for tumor cells in culture and as phototoxins in photodynamic therapy of tumor xenografts. Thus, boronated porphyrins and chlorins emerge as promising class of anticancer agents with potentially multiple advantages: the chemotherapeutic drugs alone and photo- and radiosensitizers in binary treatments.

• Bulletin of the Korean Chemical Society
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• v.34 no.8
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• pp.2256-2260
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• 2013

A new quinoline-based acylhydrazone (1) has been synthesized and applied as a fluorescent probe. Probe 1 exhibits high selectivity and sensitivity to $Cu^{2+}$ with fluorescence "ON-OFF" behavior in HEPES buffered (1‰ DMSO, HEPES 20 mM, pH = 7.4) solution. The on-site generated 1-$Cu^{2+}$ complex displays excellent selectivity to sulfide ions with fluorescence "OFF-ON" performance through copper displacement approach.

• Bulletin of the Korean Chemical Society
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• v.22 no.4
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• pp.367-371
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• 2001

Lithium inserted into artificial carbon has been synthesized as a function of the Li concentration. The characteristics of these prepared compounds were determined from the studies using X-ray diffraction(XRD), solid nuclear magnetic resonance (NM R) spectrophotometric and differential scanning calorimeter(DSC) analysis. X-ray diffraction showed that lower stage intercalation compounds were formed with increasing Li concentration. In the case of the AG3, most compounds formed were of the stage 1 structure. Pure stage 1 structural defects of artificial graphite were not observed. 7Li-NMR data showed that bands are shifted toward higher frequencies with increasing lithium concentration; this is because non-occupied electron shells of Li increased in charge carrier density. Line widths of the Li inserted carbon compounds decreased slowly because of nonhomogeneous local magnetic order and the random electron spin direction for located Li between graphene layers. The enthalpy and entropy changes of the compounds can be obtained from the differential scanning calorimetric analysis results. From these results, it was found that exothermic and endothermic reactions of lithium inserted into artificial carbon are related to the thermal stability of lithium between artificial carbon graphene layers.

• Bulletin of the Korean Chemical Society
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• v.21 no.4
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• pp.441-445
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• 2000

A new series of three ring type liquid crystalline compounds containing partially fluorinated alkenyl or alkyl side chains together with fluorine substituted cyclohexylbiphenyls were designed and synthesized in this study. The structures of synthe sized compounds were established by 1 H, 13 C and 19 F NMR spectroscopy. The phase transition temperatures of fluorinated liquid crystalline compounds were determined by cross-polarizing mi-croscopy equipped withhot stage. All compounds were found to have nematic liquid crystalline phase with rel-atively low phase transition temperature and wide liquid crystalline temperature range. The dependence of phase transition temperatures on the chainlength falls into three categories; (a) decreasing transition tempera-tures for 4-fluoro-4'-[4-fluoro-4-(1-fluoroalkyl)cyclohexyl]biphenyl (15) series, (b) higher transition tempera-tures for odd numbered chains for 4-fluoro-4'-[4-fluoro-4-(1-fluoroalk-1-enyl)cyclohexyl]biphenyl (14) series, (c) higher transition temperatures for even numbered chains for 4-[4-(1,2-difluoroalk-1-enyl)-4-fluorocyclo-hexyl]-4'-fluorobiphenyl (16) series.

• Bulletin of the Korean Chemical Society
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• v.22 no.12
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• pp.1380-1384
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• 2001

The chemoselective reactions of 1,n-dicarbonyl compounds with allyl halides using indium metal were investigated. $\alpha-Ketoesters$ such as ethyl pyruvate, ethyl 3-methyl-2-oxobutyrate and ethyl benzoylformate reacted with a variety of allyl halides i n the presence of indium to afford hydroxy unsaturated carbonyl compounds in good to excellent yields in MeOH/HCl at $25^{\circ}C.$ For the allyl bromide, the presence of various substituents at the $\alpha$ or $\gamma$ position exhibited little effects on both the reaction rates and yields. Ethyl acetoacetate or ethyl levulinate was treated with allylindium reagent to give hydroxy unsaturated carbonyl compounds in good yield. These results mean that both reactivity and selectivity are independent of the distance between carbonyl groups. 2,3-Butanedione or 1-phenyl-1,2-propanedione reacted with allylindium to produce monoallylation product as major compound.

• The Korean Journal of Pesticide Science
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• v.19 no.2
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• pp.88-92
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• 2015

This study investigated the thermal stabilities of the four limonoidal active compounds like azadirachtin A, azadirachtin B, deacetylsalannin and salannin and of the two alkaloidal active compounds like matrine and oxymatrine in commercial biopesticides at incubated conditions ($30^{\circ}C$, $35^{\circ}C$, $40^{\circ}C$, $45^{\circ}C$, and $54^{\circ}C$). Half-lives of the limonoidal compounds in biopesticide ranged from 25.6 to 220 days. And the total limonoid contents changed over 15% after 14 days at all the conditions in the tested biopesticide containing neem extract. On the contrary, half-lives of the alkaloidal compounds in biopesticide showed the ranges from 231 to 346 days. And total alkaloidal compounds in all the tested biopesticides containing Sophora flavescens extracts decomposed below 15% after 14 days incubation at $54^{\circ}C$.

• Asian Pacific Journal of Cancer Prevention
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• v.17 no.1
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• pp.51-55
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• 2016

Phytochemical investigation of Pistacia integerrima has highlighted isolation of two known compounds naringenin (1) and dihydrokaempferol (2). A crude extract and these isolated compounds were here evaluated for their effects on reversion of multidrug resistance (MDR) mediated by P-glycoprotein (P-gp). The multidrug resistance P-glycoprotein is a target for chemotherapeutic drugs from cancer cells. In the present study rhodamine-123 exclusion screening test on human mdr1 gene transfected mouse gene transfected L5178 and L5178Y mouse T-cell lymphoma cells showed excellent MDR reversing effects in a dose dependent manner. In-silico molecular docking investigations demonstrated a common binding site for Rhodamine123, and compounds naringenin and dihydrokaempferol. Our results showed that the relative docking energies estimated by docking softwares were in satisfactory correlation with the experimental activities. Preliminary interaction profile of P-gp docked complexes were also analysed in order to understand the nature of binding modes of these compounds. Our computational investigation suggested that the compounds interactions with the hydrophobic pocket of P-gp are mainly related to the inhibitory activity. Moreover this study s a platform for the discovery of novel natural compounds from herbal origin, as inhibitor molecules against the P-glycoprotein for the treatment of cancer.

• Bulletin of the Korean Chemical Society
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• v.34 no.5
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• pp.1407-1413
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• 2013

A new compound, perforaphenonoside A (1), along with 11 known compounds (2-12) were isolated from a methanol extract of adventitious roots of Hypericum perforatum. Their chemical structures were elucidated using chemical and physical methods as well as comparison of NMR and mass spectral data with previously reported data. Their inhibition of NF-${\kappa}B$ and activation of PPAR was measured in HepG2 cells using a luciferase reporter system. Among the compounds 3, 6, 7 and 12 inhibited NF-${\kappa}B$ activation stimulated by TNF${\alpha}$ in a dose-dependent manner, with $IC_{50}$ values ranging from 0.85 to $8.10{\mu}M$. Moreover, compounds 1-3, 7, 11 and 12 activated the transcriptional activity of PPARs in a dose-dependent manner, with $EC_{50}$ values ranging from 7.3 to $58.7{\mu}M$. The transactivational effects of compounds 1-3, 7, 11 and 12 were evaluated on three individual PPAR subtypes. Among them, compound 2 activated $PPAR{\alpha}$ transcriptional activity, with 153.97% stimulation at $10{\mu}M$, while compounds 1, 2 and 11 exhibited transcriptional activity of $PPAR{\gamma}$, with stimulation from 124.76% to 126.91% at $10{\mu}M$.

• Bulletin of the Korean Chemical Society
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• v.35 no.12
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• pp.3571-3575
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• 2014

Proteasome, a multicatalytic protease complex, has been validated as a promising therapeutic target in oncology. Carfilzomib (Kyprolis$^{(R)}$), a tetrapeptide epoxyketone, irreversibly inhibits the chymotrypsin-like (CT-L) activity of the proteasome and has been recently approved for multiple myeloma treatment by FDA. A chemistry effort was initiated to discover the compounds that are reversibly inhibit the proteasome by replacing the epoxyketone moiety of carfilzomib with a variety of ketones as reversible and covalent warheads at the C-terminus. The newly synthesized compounds exhibited significant inhibitory activity against CT-L activity of the human 20S proteasome. When the compounds were tested for cancer cell viability, 14-8 was found to be most potent in inhibiting Molt-4 acute lymphoblastic leukemia cell line with a $GI_{50}$ of $4.4{\mu}M$. Cytotoxic effects of 14-8 were further evaluated by cell cycle analysis and Western blotting, demonstrating activation of apoptotic pathways.

• Journal of the Korean Chemical Society
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• v.12 no.4
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• pp.184-189
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• 1968

Molybdenum chelate compounds have been prepared as new compounds; $MoO(CNS)_3{\cdot}2C_{12}H_8N_2,\;MoO(CNS)_3{\cdot}C_{10}H_8N_2$ and $MoO(CNS){\cdot}2C_9H_6ON$. Properties and configuration of the complexes were studied by chemical and physical method.