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Suigen, South Korea

Disclosed are a novel montelukast 4-halobenzylamine salt, and a method for preparing a montelukast sodium salt by using the same. In the disclosed method, a montelukast 4-halobenzylamine salt represented by Formula 2 or a montelukast sodium salt represented by Formula 1 is prepared by obtaining a compound represented by Formula 3 from a compound represented by Formula 5, in the same reactor, without an additional obtaining process. In Formula 2, X represents F, Cl, Br or I.

Kim M.K.,Chung - Ang University | Lee T.H.,Chung - Ang University | Suh J.H.,Chung - Ang University | Eom H.Y.,Chung - Ang University | And 8 more authors.
Journal of Chromatography B: Analytical Technologies in the Biomedical and Life Sciences | Year: 2010

A rapid and sensitive liquid chromatography-electrospray ionization tandem mass spectrometry method (LC-ESI-MS/MS) was developed and validated for the determination of goserelin in rabbit plasma. Various parameters affecting plasma sample preparation, LC separation, and MS/MS detection were investigated, and optimized conditions were identified. Acidified plasma samples were applied to Oasis® HLB solid-phase extraction (SPE) cartridges. Extracted samples were evaporated under a stream of nitrogen and then reconstituted with 100μL mobile phase A. The separation was achieved on a Capcell-Pak C18 (2.0mm×150mm, 5μm, AQ type) column with a gradient elution of solvent A (0.05% acetic acid in deionized water/acetonitrile=85/15; v/v) and solvent B (acetonitrile) at a flow rate of 250μL/min. The LC-MS/MS system was equipped with an electrospray ion source operating in positive ion mode. Multiple-reaction monitoring (MRM) of the precursor-product ion transitions consisted of m/z 635.7→m/z 607.5 for goserelin and m/z 424.0→m/z 292.1 for cephapirin (internal standard). The proposed method was validated by assessing specificity, linearity, limit of quantification (LOQ), intra- and inter-day precision and accuracy, recovery, and stability. Linear calibration curves were obtained in the concentration range of 0.1-20ng/mL (the correlation coefficients were above 0.99). The LOQ of the method was 0.1ng/mL. Results obtained from the validation study of goserelin showed good accuracy and precision at concentrations of 0.1, 1, 5, 10, and 20ng/mL. The validated method was successfully applied to a pharmacokinetic study of goserelin after a single subcutaneous injection of 3.6mg of goserelin in healthy white rabbits. © 2010 Elsevier B.V.

Yoo N.Y.,Catholic University of Korea | Youn Y.S.,Pusan National University | Oh N.M.,Catholic University of Korea | Oh K.T.,Chung - Ang University | And 4 more authors.
Colloids and Surfaces B: Biointerfaces | Year: 2011

The purpose of this study was to fabricate porous poly(lactide-co-glycolide) (PLGA) microparticles for efficient pulmonary deposition and increased therapeutic duration of the antioxidant anthocyanin (ATH). These microparticles were prepared by a water-in-oil-in-water (W 1/O/W 2) multi-emulsion method with vaporizing ammonium bicarbonate (AB) as a porogen and starch as a viscous additive. High porosity achieved by the decomposition reaction of AB to the base of ammonia, carbon dioxide, and water vapor at 50°C enabled efficient deposition of ATH throughout the entire lung in BALB/c mice. In addition, the porous microparticles incorporating starch showed sustained ATH release characteristics (up to 5 days) and protracted antioxidant activity (up to 5 days) for 2,2-diphenyl-1-pikryl-hydrazyl (DPPH) radicals, which was comparable to that of the porous microparticles without starch which completely released ATH in 2h. Furthermore, these porous microparticles incorporating starch led to longer ATH residence (up to 20 days) in in vivo lung epithelium. We believe that this system has great pharmaceutical potential as a long-acting antioxidant for continuously relieving oxidative stress in pulmonary diseases like chronic obstructive pulmonary disease (COPD). © 2011 Elsevier B.V.

Lee W.R.,Catholic University of Korea | Oh K.T.,Chung - Ang University | Park S.Y.,Catholic University of Korea | Yoo N.Y.,Catholic University of Korea | And 6 more authors.
Colloids and Surfaces B: Biointerfaces | Year: 2011

Herein, we describe magnetic cell levitation models using conventional polymeric microparticles or nanoparticles as a substrate for the three-dimensional tumor cell culture. When the magnetic force originating from the ring-shaped magnets overcame the gravitational force, the magnetic field-levitated KB tumor cells adhered to the surface area of magnetic iron oxide (Fe3O4)-encapsulated nano/microparticles and concentrated clusters of levitated cells, ultimately developing tumor cells to tumor spheroids. These simple cell culture models may prove useful for the screening of anticancer drugs and their formulations. © 2011 Elsevier B.V.

Oh N.M.,Catholic University of Korea | Oh K.T.,Chung - Ang University | Youn Y.S.,Sungkyunkwan University | Lee D.-K.,Dongkook Pharm. Co. | And 3 more authors.
Colloids and Surfaces B: Biointerfaces | Year: 2013

Advanced materials that have controllable pH-responsive properties when submerged in the lysosome have a great potential in intracellular drug delivery. We developed novel poly(l-amino acid) nanogels that were prepared by a facile cross-linking of poly[. l-aspartic acid-g-(3-diethylaminopropyl)]-b-poly(ethylene glycol)-maleimide [poly(l-Asp-g-DEAP)-b-PEG-Mal] and poly(l-aspartic acid-g-ethyl thiol)-b-PEG [poly(l-Asp-SH)-b-PEG] in an oil/water emulsion condition. Interestingly, these nanogels (~125. nm in diameter) modulated volume expansion (~375. nm in diameter) in a lysosomal pH (~pH 5.0) due to an extensive proton absorption of DEAP at a low pH, which mediated lysosome swelling and the subsequent lysosome destabilization. In the in vitro tumor cell cytotoxicity test, they encouraged tumor cell death, probably owing to the leakage of lysosomal enzymes. Furthermore, encapsulating antitumor drug (e.g., doxorubicin, DOX) into these nanogels enhanced tumor cell cytotoxicity. We conclude that this nanogel system will have great potential for tumor therapy. © 2012 Elsevier B.V.

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