• 약학회지
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• 제36권4호
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• pp.370-378
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• 1992

A simple and sensitive high performance liquid chromatographic method to quantitate ${\alpha}-keto$ acids in serum and urine was investigated. ${\alpha}-Keto$ acids react with 1,2-diamino-4,5-methylenedioxybenzene (DMB) in the presence of 2-mercapto-ethanol and sodium hydrogen sulfite to form highly fluorescent derivatives, substituted 6,7-methylenedioxyquinoxalinol. The derivatization procedure was performed in water bath at $100^{\circ}C$, and completed within 50 min. By the use of a reversed-phase column and multi-step gradient with two solvents, a mixture containing twelve of these derivatives were efficiently resolved within 35 minutes. The optimal wavelengh of the fluorescence detector are ${\lambda}_{ex}=364\;nm$ and ${\lambda}_{em}=445\;nm$. The quantitation of the individual ${\alpha}-Keto$ acids was reproducible with relative standard deviation of $3.0{\sim}7.9%$ and had a detection limits of $10{\sim}60$ fmol, except for p-hydroxyphenylpyruvic acid (960 fmol).

• Journal of Nutrition and Health
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• 제7권4호
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• pp.30-32
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• 1974

Hemoglobinemia is found in hemolytic anemia, paroxysmal nocturnal hemolobinuria and paroxysmal hemoglobinuria. Recently increasing use of extracorporeal circulation in cardiac surgery has stimulated the development of more precise methods for rapidly evaluating the formation and clearance of extracoporeal hemoglobin. A spectrophotometric method of analysis seemed to offer the best solution to the requirements. The method presented is on the basis of hemoglobin derivatives converted to cyanmethemoglobin, and the absorbance is measured in a spectrophotometer at 540 and 680 nm. The blank value ismeasured at 680 nm while the absorbance at 540 nm measures the hemoglobin derivatives. This method estimates all the hemoglobin derivatives such as oxyhemoglobin, carboxyhemoglobin, methemoglobin, sulfhemoglobin and hemialbumin. The method was tested in recovery experiments, which is given table 1. A good degree of correlation was obtained in a comparision with the method described by Crosby and Furth for non-hemolyzed serum. The spectrophotometric technique described offers many advantages in speed and simplicity over the chemical procedure.

• 한국염색가공학회지
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• 제11권6호
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• pp.7-17
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• 1999

Aminophosphazene derivatives were prepared from hexachlorocyclotriphosphazene and used for the curing agents of epoxy resins. The effect of the curing agent on the dynamic viscoelastic properties, flame proofing, and heat resistance of the cured epoxy resins were investigated and compared with those for the epoxy resins cured with aliphatic and aromatic amines. The epoxy resin cured by 1,1-diamino-3,3,5,5-tetrachlorocyclotriphosphazene showed the highest storage modulus and glass transition temperature when cured at 19$0^{\circ}C$ for 6 hours. The epoxy resins cured with phosphazene derivatives showed superior flame proofing to those with aliphatic amine and aromatic amine. Particularly it is an effective curing agent for epoxy resins to enhance the storage modulus, flame proofing and resistance to heat.

• 한국응용약물학회:학술대회논문집
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• 한국응용약물학회 1996년도 춘계학술대회
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• pp.162-162
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• 1996

새로 합성된 6-exomethylene penamsulfone derivatives 7종에 대해 In Vitro antibacterial activities를 Broth Microdilution법으로 Sulbactam-Na(SAM), Clavulanic acid-K(CLA)와 Cefotaxime-Na(CFT), Ampicillin Trihydrates(AMP), Amoxicillin-Na(AMX), Cefoperazone(CFZ)을 병용투여하여 $\beta$-lactamase 생성 균주(30 여종)에 실시, MIC를 구하였다. 균주에 따라 SAM, CLA에 비해 CH1145, CH1155 등이 우수한 효과를, CH1140, CH2150등이 유사한 효과를 보였다.

• Archives of Pharmacal Research
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• 제27권11호
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• pp.1093-1098
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• 2004

In this study, certain 3-methyl-2-[4-(substituted amino carbonyl)anilino] quinoxalines, (2a-d) and (3a-d), were synthesized from the new key compound 2-[4-(ethoxycarbonyl)anilino]-3-methyl quinoxaline (1). In addition, a series of 2-[4-(arylidene hydrazinocarbonyl)anilino]-3-methyl quinoxalines (5a-e), as well as their cyclized oxadiazolinyl derivatives (6a-e), and a series of 2-[4-$N^2$-acylhydrazinocarbonyl)anilino]-3-methyl quinoxalines (7a-d), as well as their cyclized oxadiazolyl derivatives (8a-d) were also prepared. Some of these derivatives were evaluated for antimicrobial activity in vitro. It was found that all the selected compounds exhibit antimicrobial activity and that compound 5b had a broad spectrum of activity.

• Natural Product Sciences
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• 제19권3호
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• pp.258-262
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• 2013

Three ergosterol derivatives, ergosta-4,6,8(14),22-tetraen-3-one (1), ergosta-7,24(28)-dien-3-ol (2), and 5,8-epidioxyergosta-6,22-dien-3-ol(3) were isolated from the fruit body of Phellinus pini. Their structures were based on spectroscopic methods including IR, MS, and NMR (1D and 2D). These compounds were evaluated for their activity to decrease melanin production in ${\alpha}$-MSH (melanocyte stimulating hormone) activated B16F10 cells. Compound 1, 2, and 3 reduced melanin content in a dose-dependent manner at concentrations of 5~15 uM. They also suppressed the tyrosinase expression of protein and m-RNA level dose dependently by western blot analysis and RT-PCR experiment in B16F10 murine melanoma cells.

• International Journal of Naval Architecture and Ocean Engineering
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• 제7권5호
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• pp.848-872
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• 2015

Hydrodynamic derivatives or coefficients are required to predict the maneuvering characteristics of a marine vehicle. These derivatives are obtained numerically for a DTMB 5512 model ship by virtual simulating of captive model tests in a CFD environment. The computed coefficients are applied to predict the turning circle and zig-zag maneuvers of the model ship. The comparison of the simulated results with the available experimental data shows a very good agreement among them. The simulations show that the CFD is precise and affordable tool at the preliminary design stage to obtain maneuverability performance of a marine vehicles.

• Archives of Pharmacal Research
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• 제10권3호
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• pp.153-157
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• 1987

Reaction of oxazolin-5-ones 1 with p-amino-diphenylamine was resulted in the formation of the corresponding imidazoline-5-ones 2 which on treatment with sulphur afforded phenothizaines 3. Acridine derivatives 5 were obtained from acetylaminodiphenyl amines derivatives 6 on heating with AnCl$_2$ at $200^{\circ}C.$3 reacted with chloroacetyl chloride to give 7 which reacted in turn with different amines to give 8. Antibacterial activity of the obtained products was studied.

• 한국응용과학기술학회지
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• 제28권2호
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• pp.196-202
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• 2011

Coumarin derivatives were shown to possess valuable pharmacological properties such as anticancer/anti carcinogenic, anti-inflammatory, anti helicobacter, anti genotoxic, neuroprotective and dietary effect. In this study, novel coumarin derivatives structurally related to 7-geranyloxycoumarin were effectively synthesised in good yields by $Cs_2CO_3$/acetonitrile in mild condition. The synthesis of geranyloxycoumarin derivatives in weak base($Na_2CO_3$, $K_2CO_3$, $Cs_2CO_3$ etc)/$CH_3CN$ at room temperature obtained in good yield. On the other hand, the reaction of geranyloxycoumarin formation in strong base(NaOH, KOH, CsOH etc)/$CH_3CN$ at reflux condition obtained in low yield.

• Bulletin of the Korean Chemical Society
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• 제31권10호
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• pp.2884-2888
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• 2010

Two red fluorescent DCJTB derivatives (Red 1 and 2) based on modified pyrans were synthesized and their electroluminescent properties were investigated. Multilayered OLEDs were fabricated with the device structure of ITO/NPB (40 nm)/Red 1, 2 or DCJTB (0.5 or 1%): $Alq_3$ (20 nm)/$Alq_3$ (40 nm)/Liq (2 nm)/Al. All devices exhibited efficient red emissions. In particular, a device containing emitter Red 2 as a dopant in the emitting layer, the maximum luminance was $8737\;cd/m^2$ at 12.0 V, the luminous and power efficiencies were 2.31 cd/A and 1.25 lm/W at $20\;mA/cm^2$, respectively. The peak wavelength of the electroluminescence was 638 nm with the CIE (x,y) coordinates of (0.63, 0.36) at 7.0 V.