• Bulletin of the Korean Chemical Society
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• v.30 no.2
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• pp.373-377
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• 2009

A pathway for the formation of normal $CoAl_2O_4$ particles is suggested. The optimal amount of malonic acid was determined, and the characteristics of the obtained powders were investigated. Normal $CoAl_2O_4$ powders were prepared using solutions of malonic acid and metal nitrates. X-ray diffraction, Brunauer-Emmett-Teller (BET) and scanning electron microscope (SEM) measurements, as well as Fourier transform infrared (FTIR) and ultraviolet/visible (UV-Vis) spectroscopy were carried out. Normal $CoAl_2O_4$ crystallites were formed by a solid state reaction between $CoAl_2O_4$ and amorphous aluminum oxide. The optimal molar ratio of malonic acid to the nitrate anions present in the initial solution was found to be 0.30~0.35. The particles were composed of agglomerates of primary particles. The primary particles were 40 nm in size. This size was relatively constant regardless of the preparation temperature. However, the size of the agglomerated particles increased to 220 nm with increasing temperature.

• Korean Journal of Microbiology
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• v.25 no.1
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• pp.17-22
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• 1987

For the purpose of securing of strains which can be usefully utilized to study symbiosis between Rhizobium and legume plant, A. tumefaciens T7 was isolated and characterized and then subgroup biovar was determined. A. tumefaciens T7 induced smooth tumor like nopaline type one and did not grow at $37^{\circ}C$ and in the presence of 2% NaCl on yeast extract mannitol medium. The strain was able to grow on the New and Kerr selective media and utilize erythritol but not phenylalanine, tryptophan, and tartarate as a sole carbon source. Negative results were obtained from 3-keto-lactose production and oxidase test. The strain produced alkalifrom malonate and citrate and showed acid litmus milk reaction At least two large plasmids were detected in the cell lysate. According to all of these results, it could be concluded that subdivision of isolated strain was biovar 2.

• BMB Reports
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• v.32 no.4
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• pp.414-418
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• 1999

A novel gene for malonyl-CoA decarboxylase was discovered in the mat operon, which encodes a set of genes involved in the malonate metabolism of Rhizobium trifolii (An and Kim, 1998). The subunit mass determined by SDS-PAGE was 53 kDa, which correspond to the deduced mass from the sequence data. The molecular mass of the native enzyme determined by field flow fractionation was 208 kDa, indicating that R. trifolii malonyl-CoA decarboxylase is homotetrameric. R. trifolii malonyl-CoA decarboxylase converted malonyl-CoA to acetyl-CoA with a specific activity of 100 unit/mg protein. Methylmalonyl-CoA was decarboxylated with a specific activity of 0.1 unit/mg protein. p-Chloromercuribenzoate inhibited this enzyme activity, suggesting that thiol group(s) is(are) essential for this enzyme catalysis. Database analysis showed that malonyl-CoA decarboxylase from R. trifolii shared 32.7% and 28.1% identity in amino acid sequence with those from goose and human, respectively, and it would be located in the cytoplasm. However, there is no sequence homology between this enzyme and that from Saccharopolyspora erythreus, suggesting that malonyl-CoA decarboxylases from human, goose, and R. trifolii are in the same class, whereas that from S. erythreus is in a different class or even a different enzyme, methylmalonyl-CoA decarboxylase. According to the homology analysis, Cys-214 among three cysteine residues in the enzyme was found in the homologous region, suggesting that the cysteine was located at or near the active site and plays a critical role in catalysis.

• Bulletin of the Korean Chemical Society
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• v.26 no.9
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• pp.1395-1402
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• 2005

The reaction of cis-[Cr([14]-decane)$(OH)_2]^+$ ([14]-decane = rac-5,5,7,12,12,14-hexamethyl-1,4,8,11-teraazacyclotetradecane) with auxiliary ligands {$L_a$ = acetylacetonate (acac), oxalate (ox) or malonate (mal)} leads to a new cis-[Cr([14]-decane)(acac)]$(ClO_4)_2{\cdot}(1/2)H_2O\;(1),\;cis-[Cr([14]-decane)(ox)]ClO_4{\cdot}(1/2)H_2O\;(2)\;or\;cis-[Cr([14]-decane)(mal)]ClO_4{\cdot}(1/4)H_2O\;(3)$. These complexes have been characterized by a combination of elemental analysis, conductivity, IR and Vis spectroscopy, mass spectrometry, and X-ray crystallography. Analysis of the crystal structure of cis-[Cr([14]-decane)(acac)]$(ClO_4)_2{\cdot}(1/2)H_2O$ reveals that central chromium(III) has a distorted octahedral coordination environment and two acetylacetonate-oxygen atoms are bonded to the chromium(III) ion in the cis positions. The angle $N_{axial}-Cr-N_{axial}$ deviates by $11^{\circ}$ from the ideal value of $180^{\circ}$ for a perfect octahedron. The bond angle O-Cr-O between the chromium(III) ion and the two acetylacetonate-oxygen atoms is close to $90^{\circ}$. The bond lengths of Cr-O between the chromium and the acetylacetonate-oxygen atoms are 1.950(3) and 1.954(2) $\AA$. They are shorter than those between chromium and nitrogen atoms of the macrocycle. The IR spectra of 1, 2 and 3 display bands at 1560 {ν (C=O)}, 1710 {${\nu}_{as}$(OCO)} and 1660 $cm^{-1}$ {${\nu}_{as}$(OCO)} attributed to the acac, ox and mal auxiliary ligands stretching vibrations, respectively.

• Journal of the Korean Chemical Society
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• v.42 no.1
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• pp.69-77
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• 1998

(3S,4S)-1-(t-Butoxycarbonylmethyl)-3-[(S)-1-(t-butyldimethylsilyloxy)ethyl]-4-(2-diazo-2-ethoxycarbonyl-1-oxoethyl)-2-azetidinone (14) was prepared from 4-styryl-2-azetidinone 7b via a sequence of reactions involving N-alkylation with bromoacetate, ozonolysis, oxidation, condensation with magnesium ethyl malonate, and diazo transfer reaction. (3S,4S)-3-[(S)-1-(t-Butyldimethylsilyloxy)ethyl]-4-(3-diazo-3-ethoxycarbonyl1-hydroxypropyl)-2-azetidinone (21) was also prepared from 4-formyl-2-azetidinone 5b via a sequence of reactions involving Wittig reaction, 1,3-dipolar cycloaddition with ethoxycarbonylformonitrile oxide, catalytic hydrogenation, and diazotization. However, the final cyclization of 14 or 21 to 1-hydroxycarbapenem or 1-hydroxycarbapenam by treating with $Rh_2(OAc)_4$ was unsuccessful.

• Microbiology and Biotechnology Letters
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• v.24 no.1
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• pp.19-26
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• 1996

A phospholipase C (PLC) inhibitor (MT267-2B) was isolated from the culture broth of actinomycetes isolate MT2617-2 by the extraction with n-butanol and column chromatographic techniques. The molecular weight of the inhibitor was 1057, by the spectroscopic analyses of IR, $^{13}C$-and $^{1}H$-NMR and ESI-MS. The chemical structure of MT2617-2B was found to be a macrolide compound consisted of a hemiketal ring, polyhydroxyl and polymethyl groups, which had a malonate and guanidine group as its side chain. MT2617-2B produced its two isomers having the same molecular weight by standing in methanol solution at room temperature. Therefore, MT2617-2B was identified as copiamycin and niphithricin A, macrolide antibiotics. The values of $IC_{50}$ against PLC-${\gamma}$1 and PLC-${\beta}$1 were 25 and 50${\mu}$g/ml, respectively. MT2617-2B had antimicrobial activities against Staphylococcus aureus and Candida albicans, but not against Escherichia coli.

• Proceedings of the Korean Society of Applied Pharmacology
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• 1993.04a
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• pp.73-73
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• 1993

As part of a research program to develope 3rd generation anti tumor platinum complexes, a series of platinum complexes which have 4, 5-bis-(aminomethyl)- 1, 3-dioxolane derivatives as bidenate amine ligands, represented by the general structual formula was prepared. The R$_1$ and/or R$_2$ substituents in this series of platinum complexes can be hydrogen. alkyl, of jointly formed cyclohexane. Two Xs can be a bidenate leaving ligand such as 1, 1-cyclobutanedicarboxylate, malonate, dimethylmalonate, ethylmalonate, glycolate, L-lactate, or N-methyliminodiacetate. From based on the pharmacological and toxicological studies, we have chosen SKI 2053R, cis-malonato[(4R, 5R)-4, 5-bis(aminomethyl)-2-isopropyl-1, 3-dioxolane] platinum(II) complex (NSC D644591) as a candidate for clinical evaluation. The antitumor activity of a new anti tumor platinum complex, cis-malonato [(4R, 5R)-4, 5-bis(aminomethyl)-2-isopropyl-1, 3-dioxolane] platinum(II) (SKI 2053R, NSC D644591), was compared with those of cisplatin and carboplatin using murine tumors. We evaluated three platinum complexes against L1210/CPR, a subline of L1210 leukemia resistant to cisplatin for their abilities to overcome tumor resistance to cisplatin. The in vitro cytotoxicity of SKI 2053R to L1210 cell line was 2.5-fold less potent thann that of cisplatin, and was 10-fold more cytotoxic than that of carboplatin. SKI 2053R retained similar cytotoxic effect and anti tumor activity to L1210/CPR cell line, like the cytotoxicity of SKI 2053R to L1210 cell line, while either cisplatin or carboplatin had not property to overcome the acquired cisplatin-resistance. SKI 2053R exhibited greater or comparable antitumor activity than cisplatin or carboplatin in murine tumor models.

• The Journal of the Korean Society for Microbiology
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• v.19 no.1
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• pp.55-64
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• 1984

The clinical specimens used in this study were collected during the period from March 4, to December 30, 1983, from children's hospitals in Seoul area. They came from clinically apparent cases of diarrheal disease in hospitals. Many specimens were taken from rectal Swabs. During this period, 2166 stool cultures were streaked onto MacConkey plate and were them deposited in selenite broth. Colonies resembling pathogens on MacConkey medium were picked to KIA, Urea agar, malonate broth, ONPG broth, SIM. Reaction on those media cultures were identified biochemically with using API 20E test kit and confirmed serologically with commercially avabile Salmonella antisera(Difco) or Shigella antisera(Denka, Japan). The sensitivity of Salmonella and Shigella tested to ampicillin cephalosporin, chloramphenicol, colistin, gentamicin, tetracycline, streptomycin, nalidixic acid, neomycin, polymyxin B was performed by means of disc diffusion method recommended by Bauer-Kirby, using the discs prepared in BBL Laboratory. 1. There were 34 (1.6%) isolations of Salmonella cultures and 52(2.4%) isolations of Shigella from the 2,116 specimens. Only 53%of Salmonella were isolated by direct streaking on MacConkey plating media, by contrast, 80% of the Shigella were isolated directly. 2. Shigella flexneri types comprised 56% of the Shigellae isolate from 52 Shigellae identified 24% of Salmonella enteritidis ser typhimurium were identified. 3. Concerning to Salmonella and Shigella occurance according to month and sex, They shows relatively higher for the male than in case of female, and 2-3 age were shown the highest group. 4. October is the month with highest incidences. 5. In the sensitivity patterns of Shigellae, most of them were appeared to be resistant ampicillin, streptomycin, tetracycline, in case of Salmonella, 15% of them were resistant to chloramphenicol.

• Bulletin of the Korean Chemical Society
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• v.31 no.1
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• pp.47-51
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• 2010

A powder, containing 80 percent of blue cobalt aluminate $(CoAl_2O_4)$ crystallites, was synthesized at $210 ^{\circ}C$ using a (metal nitrate-malonic acid-ammonium hydroxide-ammonium nitrate) system. The optimal amount of concentrated ammonia water and initial decomposition temperature were determined for the blue $CoAl_2O_4$ crystallites preparation. Three $CoAl_2O_4$ precursor pastes, corresponding to the various amounts of concentrated ammonia water, were prepared by evaporating the initial solutions in an electric furnace fixed at $80 ^{\circ}C$ under a vacuum of 25 torr. The initial solution was used to dissolve the starting materials. The powder with the maximum content (80%) of blue $CoAl_2O_4$ crystallites was prepared when the prepared precursor was decomposed at $210 ^{\circ}C$. The blue $CoAl_2O_4$ crystallite content in the prepared sample decreased with increasing initial decomposition temperature. For 0.2 mole of the $Al^{3+}$ ion, the chemical compositions of the precursor corresponded to molar ratios of 0.4, 1.40, 2.56 and 2.00 for the $Co^{2+}$ ion, malonic acid, ammonia and ammonium nitrate per mole of the $Al^{3+}$ ion, respectively. The blue $CoAl_2O_4$ crystallite content in the sample decreased with the amount of ammonia deviated from the optimal value. The characteristics of the powders were examined using X-ray diffraction, optical microscopy, Fourier transformation infrared spectroscopy and the Brunauer-Emmett-Teller technique.

• Archives of Pharmacal Research
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• v.29 no.10
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• pp.840-844
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• 2006

For the exploration of pharmacophoric moiety of malloapelta B (1) possessing the inhibitory activity of $NF-{\kappa}B$ activation, structural variation of ${\alpha},{\beta}-unsaturated$ carbonyl motif was attempted. 1 was reduced by catalytic hydrogenation, sodium borohydride, and lithium aluminumhydride. Catalytic hydrogenation with 30 psi or 15 psi of $H_2$ gas of 1 generated 8-butyl-5,7-dimethoxy-2,2-dimethylchroman (2) and 1-(5,7-dimethoxy-2,2-dimethylchroman-8-yl)butan-1-one (3), respectively. Reduction with sodium borohydride occurred at the double bond of ${\alpha},{\beta}-unsaturated$ ketone of 1 to give 1-(5,7-dimethoxy-2,2-dimethyl-2H-chromen-8-yl)butan-1-one (4). Reduction of 1 with lithium aluminumhydride and then quenched with methanol and water produced unexpected products, 1-(5,7-dimethoxy-2,2-dimethyl-2H-chromen-8-yl)-3-methoxy-1-butene (5) and 1-(5,7-dimethoxy-2,2-dimethyl-2H-chromen-8-yl)-3-hydroxy-1-butene (6). These are formed from the isomerization of initial product 9 through the continuous conjugate carbocation intermediate 11. Addition of ethylmagnesium bromide and dimethyl malonate anion to 1 gave the conjugate adducts 7 and 8. Ethylmagesium bromide and sodium borohydride reduction unusually gave the conjugate addition due to steric congestion around carbonyl group of 1. Compound 2 exhibits the reduced inhibitory activity against $NF-{\kappa}B$ activation and the others do not show the activity. Therefore ${\alpha},{\beta}-unsaturated$ carbonyl group of 1 should be important for its inhibitory activity.