• The Korean Journal of Food And Nutrition
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• v.11 no.3
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• pp.267-271
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• 1998

The photochemical carcinogenic reaction mechanism and molecular carcinogenic intensity through the reaction of dibromo carbene and diazomethane with dehydroacetic acid and coumarin have been studied under the two kinds of photolysis. The reaction intensities show the degree of carcinogenic activity. Under the condition of UV/vis light source, the yield of high toxic carcinogenetic carbene intermediate is produced less than those of the laser flash photolysis.

• Korean Journal of Microbiology
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• v.27 no.2
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• pp.108-116
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• 1989

Based on the specificty of recognition of the vacuolar arginine transporter, N-p-nitrobenzoxycarbonyl (NBZ)-L-arginyl diazomethane was synthesized and used as an affinity label specific for the arginine transporter. This arginyl derivative ingibited both ATP-dependent and independent L-arginine transport into vacuolar membrane vesicles. When vacuolar proteins were labeled with radioactive NBZ arginyl diazomethane, the binding was irreversible, detached by treatment with base and blocked by treatment with cysteinyl blocking groups suggesting cysteine as a labeling site.

• Journal of the Korean Chemical Society
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• v.48 no.3
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• pp.331-334
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• 2004

• Korean Journal of Microbiology
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• v.27 no.2
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• pp.117-123
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• 1989

Radioactive N-$\alpha$-p-nitrobenzoxycarbonyl (NBZ)-L-[2,$3-^{3}$H] arginyl diazomethane was used as an affinity label for the vacuolar arginine transporter in Neurospora crassa. Vacuolar matrix proteins were removed by fracturing the membranes with freeze-thaw method in dry ice/ethanol bath. Vacuolar membrane proteins were then wasged with 500mM NaCl to remove ionically bound derivatives and peripheral membrane proteins from vacuolar membranes. After dissolved in 1% Titon X-100, dissolved vacuolar memvrane proteins were separated with molecular sieve column chromatography, anion and cation exchange chromatographies. The arginine transporter was purified giving the purification factor of 1136.

• Journal of the East Asian Society of Dietary Life
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• v.4 no.1
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• pp.79-86
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• 1994

Food quality in food processing and storage were affected by the kinds of phenolics involved. To analyze phenolics of Chebulae Fructus by the way of GC-MSm methylation and trimethylsilyation(TMS) are necessary. The methods of methylation were dimethyl sulfate method and diazomethane method. so this study was undertaken to research the better methylation method before measuring GC-MS. But dimethyl sulfate method of methylation was not sufficient to analyze phenolics. So the phenolics of Chebulae Fructus were analyzed by the diazomethane methylation method and TMS with the pyridine, N-O-bis-trimethylsilyl-acetamide(BSTFA) and trimethylchlorosilane(TMCS). With the exception of pyrogallol and phloroglucinol in insoluble phenolics of Chebulae Fructus, the greater part of phenolics. analysis could be analyzed by GC-MS in company with diazomethane methylation method and TMS.

• Journal of the Korean Chemical Society
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• v.38 no.5
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• pp.372-376
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• 1994

The penicillin-derived 4-mercaptoazetidin-2-one(2a) was unstable in basic media, but it reacted with electrophiles such as acetyl chloride, methyl chloroformate, ethyl iodoacetate, diethyl azodicarboxylate in the presence of triethylamine or pyridine to give the products such as S-acetyl, S-methoxycarbonyl, S-ethoxycarbonylmethyl, and S-diethoxycarbonylhydrazino compounds. However S-methylation could not be done with methyl iodide, but with diazomethane. The reactivity of isomer 3a toward electrophiles was almost the same as that of compound 2a.

• Bulletin of the Korean Chemical Society
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• v.27 no.7
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• pp.1083-1085
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• 2006

• Journal of Photoscience
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• v.2 no.2
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• pp.103-106
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• 1995

For studying chlorophyll biosynthetic heterogeneity of plants, it is necessary to establish a technique for microassay of a putative monovinyl and divinyl protoporphyrin IX. Precise determination of the amounts of monovinyl and divinyl protoporphyrin IX is difficult with optical electronic spectroscopy even at 77$\circ$C. Such a problem could be solved by conversion of protoporphyrin IX to protoporphyrin IX dimethylester with diazomethane and subsequent Mg insertion into protoporphyrin IX dimethylester by reaction with a Grignard solution. The proportion of monovinyl and divinyl Mg-protoporphyrin IX dimethylester formed was measured instead of direct measuring that of protoporphyrin IX by low-temperature spectrofluorometry. The relative proportions of monovinyl and divinyl of protoporphyrin IX, Mg-protoporphyrin IX, and Mgprotoporphyrin IX dimethylester have not changed during the chemical conversion steps. This analysis system could be useful for the study of the monovinyl and divinyl chlorophyll biosynthetic routes in plants.

• YAKHAK HOEJI
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• v.6 no.1
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• pp.1-4
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• 1962

A new tannin, polygagallin, related to acertannin, is isolated from air-dried leaves of Acer ginnala Max. as prismatic crystals with 1/2 H$_{2}$O per mole, m.p.154-155.deg. and [.alpha.]$_{D}$$^{29}$ +43.79.deg. C. Polygagllin gives hexaacetate, m.p.164.5.deg. C, [.alpha.]$_{D}$$^{28}$ +42.deg. C, on treating with anhydroacetic acid and on treating with diazomethane, gives trimethyl ether, m.p.176.deg. C, [.alpha.]$_{D}$$^{22}$ +53.43, which yields triacetate, m.p.160.5.deg. C, [.alpha.]$_{D}$$^{22}$ + 132.5.deg. C, on acetylation and is not attacked by periodate. On hydrolysis, trimethoxypolygagallin yields one mole of polygalitol and that of trimethoxygallic acid. By the above results polygalallin has been established as 3-galloylpolygalito.ygalito.galallin has been established as 3-galloylpolygalito.

• Journal of Food Hygiene and Safety
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• v.10 no.4
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• pp.239-247
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• 1995

Analytical method for saccharin in foods was developed using gas chromatography/mass spectrometry(GC/MS). Methylation with diazomethane, acetylation with MBTFA, and silylation with MSTFA and MTBSTFA were compared. Methylation of saccharin produced N-methylated saccharin as the major product and O-methylated saccharin as the minor one. Silylation of saccharin with MSTFA and MTBSTFA reasulted in the formation of the correponding O-silylated products, respectively. The derivatization of saccharin was optimized with MSTFA. The ions at m/z 240, 255, and 166 were monitored to characterize saccharin.