• Bulletin of the Korean Chemical Society
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• v.23 no.10
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• pp.1467-1469
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• 2002

• Preventive Nutrition and Food Science
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• v.10 no.3
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• pp.257-261
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• 2005

Marine sponges are known to produce a number of cytotoxic secondary metabolites. In the course of searching for cytotoxic metabolites from marine organisms, we have evaluated cytotoxic activities of six marine secondary metabolites isolated from various sponges. The cytotoxic compounds 1-6 were isolated by the application of various chromatographic methods, including column chromatography and HPLC. The molecular structures were mostly determined using mass spectrometry (MS) and Nuclear Magnetic Resonance (NMR) Spectroscopy. Furanosestererpenes (compounds 1-3) from Psammocinia sp., cyclitol derivatives (compounds 4 and 5) from Sarcotragus sp., and bromotyrosine-type compound (6) from an association of two sponges Jaspis wondoensis and Poecillastra wondoensis were evaluated for their cytotoxic activity against three cancer cell lines; Hep G2, HeLa, and MCF-7. All tested compounds exhibited cyctoxicity at concentrations ranging from $5\;\mug/mL\;to\;25\;\mug/mL.$ Particularly, among the tested compounds, compound 6 showed the highest potency displaying at least $80\%$ of cytotoxicity at $5\;\mug/mL$ level against all three cancer cell lines.

• Natural Product Sciences
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• v.9 no.1
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• pp.18-21
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• 2003

Guided by the brine shrimp lethality assay, a new (4) and three known cyclitol derivatives (1-3) were isolated from the marine sponge Stelletta sp. Norsarcotride A (4) showed significant cytotoxicity against a small panel of five human tumor cell lines.

• Journal of the Korean Chemical Society
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• v.15 no.3
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• pp.127-132
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• 1971

To obtain the various kinds of inosose stereomers, the process of electrochemical oxidation is more effective than chemical oxidation of myo-inositol. So that myo-inositol aqueous solution was electrolyzed by platinum and lead peroxide anode to confirming the occurrence of electrochemical oxidation. The result is that myo-inosose-2 is producing with high yield comparatively by electrolytic oxidation of myo-inositol. Also we studied about the relation between the electrolytic current efficiency and electrolytic temperature and anodic current density. The current efficiency is rising with lowering of electrolytic temperature identically in both anode such as platinum and lead peroxide and also rising with increasing of anodic current density in platinum anode, but inversely in lead peroxide.

• Journal of the Korean Chemical Society
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• v.16 no.2
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• pp.93-99
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• 1972

To obtain the various kinds of inositol stereomers, we have selected the process of electrolytic reduction of DL-epi-inosose-2 using Ni, Ta, Cu, Mo, Pb, Sn, W, Cd and Hg etc., as cathode. We think that this process gives greater variety than chemical processes. DL-epi-inosose-2 was synthesized by chemical oxidation of myo-inositol, dissolved in aqueous solution of potassium hydroxide, and used as electrolytic solution. To prevent anodic oxidation of cathode products the H-type diaphragm cell was used. As the results of paper chromatography of cathodic products, we obtained the $R_f$ values of myo-inositol and epi-inositol were in good agreement with literature values.

• Applied Biological Chemistry
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• v.13 no.3
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• pp.197-205
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• 1970

Inositols are cyclohexanehexol and they have been known to be nine stereomers. Scyllo-inositol, epi-inositol and muco-inositol could be synthesized from myo-inositol. Scyllo-inositol and epi-inositol were obtained by oxidation and reduction process from myo-inositol. Myo-inositol and epi-inositol were oxidized by treatment, in solution, with dilute hydrogen peroxide. In all cases, only axial hydroxyl groups were oxidized and monoketons were obtained. Reduction of myo-inosose-2 with sodium boron hydride was carried out in $pH2{\sim}3.$ The reduction products were equatorial alcohol but: reduction of DL-epi-inosose-2 by catalytic reduction produced axial alcohol obtained. Inositol could be esterified. Hexa-O-(p-hydroxy benzoyl)-esters of myo-inositol, scyllo-inositol, epi-inositol and muco-inositol were synthesized and their antimicrobial action on microbes were tested for application to food industry. As the results, it was found that the activities of muco-inositol ester was more vigorous than others.

• Korean Journal of Food Science and Technology
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• v.5 no.4
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• pp.240-248
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• 1973

Reduction of penta-O-acetyl-myo-inosose-2 by catalytic hydrogenation and with sodium-amalgam was carried out in alcohol solution of pH $3{\sim}4$. The former reduction product was axial-alcohol, and the latter equatorial-alcohol. On reduction of penta-O-acetyl-DL-epi-inosose-2 with sodium borohydride and sodium-amalgam in the previous condition, ax.-alcohol and eq.-alcrhol have been obtained. The synthesis of various inositol-p-hydroxybezoate are described. The esters have been characterized by paper chromatography and saponification, and their antimicrobial activities on some microbes were tested for the application of food industry. As the result, it was found that the antimicrobiol activity of epi-inositol ester was superior to its analogues.

• Korean Journal of Food Science and Technology
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• v.5 no.4
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• pp.249-257
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• 1973

In the previous work, as we have reported on the reduction of penta-O-acetyl-myo-inosose-2 and penta-O-acetyl-DL-epi-inosose-2, axial and equatorial alcohol have been produced. The synthesis of various inositol 5-nitro-2-furoate are described. The esters have been obtained by reaction of 5-nitro-2-furoylchloride with inositol stereomers in chloroform at low temperature. The ester have been characterized by paper chromatography and other determination. For the applicable purpose of food industry, their antimicrobial activities on microbes were tested, and it was found that the antimicrobial activity of muco-inositol ester was superior to the others, and considered that result would be related to the stereochemical structure.

• Journal of the Korean Chemical Society
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• v.16 no.5
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• pp.290-297
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• 1972

We have obtained the results of Cannizzaro reaction of furfural, 5-methylfurfural and 5-bromofurfural by using alcoholic potassium hydroxide solution in 95% (V/V) methanol solvent at $0{\sim}40^{\circ}C$. The results are as follows: 1) Their Cannizzaro reaction is fourth-order reaction, and the reaction of furfural proceeds 3 times as rapid as that of 5-methylfurfural and 10 times as slow as that of 5-bromofurfural. 2) Their activation energies of furfural, 5-methylfurfural and 5-bromofurfural in the reaction are 10.46Kcal/mole, 16.27Kcal/mole, and 9.62Kcal/mole respectively, and the calculated activation parameters, and ${\Delta}S^{\neq}$, increase in the order of 5-bromofurfural, furfural and 5-methyl-furfural.