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Kim K.H.,Sungkyunkwan University | Choi S.U.,Korea Research Institute of Chemical Technology | Son M.W.,Dong A Pharm Institute | Lee K.R.,Sungkyunkwan University
Chemical and Pharmaceutical Bulletin | Year: 2010

Two new phenolic amides, pharnilatins A (1) and B (2), were isolated from the seeds of Pharbitis nil. These new compounds possess a p-coumaroyl unit with a structurally unique side chain, (2S,3S)-2,3-dihydroxyputrescine. The chemical structures and absolute stereochemistries of the new compounds were determined on the basis of spectroscopic analyses including 1D- and 2D-NMR experiments and chemical reactions. Compounds 1 and 2 exhibited cytotoxicity against A549, SK-OV-3, SK-MEL-2, and HCT-15 human tumor cells. However, none of the compounds inhibited nitric oxide (NO) production in lipopolysaccharide (LPS)-activated microglia cells. © 2010 Pharmaceutical Society of Japan. Source


Kim K.H.,Sungkyunkwan University | Piao C.J.,Sungkyunkwan University | Choi S.U.,Korea Research Institute of Chemical Technology | Son M.W.,Dong A Pharm Institute | Lee K.R.,Sungkyunkwan University
Planta Medica | Year: 2010

Two new tetrahydroprotoberberine-aporphine dimeric alkaloids, corydaturtschines A (1) and B (2), and a new aporphine derivative, ethyl glausuccinate (3), together with 13 known protoberberine (416) and nine known aporphine alkaloids (1725), were isolated from the tubers of Corydalis turtschaninovii. The structures of these new compounds were determined through spectral analyses, including extensive 2DNMR data. The absolute configurations of the compounds were clarified by CD spectroscopic studies. The isolated compounds were tested for their cytotoxicity against four human cancer cell lines in vitro using a sulforhodamine B bioassay. © Georg Thieme Verlag KG Stuttgart - New York. Source


Kim K.H.,Harvard University | Kim K.H.,Sungkyunkwan University | Choi S.U.,Korea Research Institute of Chemical Technology | Son M.W.,Dong A Pharm Institute | And 3 more authors.
Journal of Natural Products | Year: 2013

Pharbinilic acid (1), the first naturally occurring allogibberic acid, was isolated from ethanol extracts of morning glory (Pharbitis nil) seeds. Its absolute configuration was determined by NOESY NMR and ECD experiments. Compound 1 showed weak cytotoxicity against A549, SK-OV-3, SK-MEL-2, and HCT-15 cells and weakly inhibited nitric oxide production in lipopolysaccharide-activated BV-2 microglia cells. © 2013 The American Chemical Society and American Society of Pharmacognosy. Source


Kim K.H.,Sungkyunkwan University | Choi S.U.,Korea Research Institute of Chemical Technology | Choi S.Z.,Dong A Pharm Institute | Son M.W.,Dong A Pharm Institute | Lee K.R.,Sungkyunkwan University
Journal of Agricultural and Food Chemistry | Year: 2011

Edible yams are tropical crops that serve as important staple foods in many parts of the world. The rhizome of Dioscorea japonica, well-known as "Japanese yam", is a food and medicinal source known as "San Yak" in Korea. Bioassay-guided fractionation and chemical investigation of the extract of this yam resulted in the identification of two new withanolides, named dioscorolide A (1) and dioscorolide B (2). The structures of these new compounds were determined by spectroscopic methods, including 1D and 2D nuclear magnetic resonance (NMR) techniques, high-resolution mass spectrometry (HRMS), and chemical methods. The cytotoxic activities of the isolates (1 and 2) were evaluated by determining their inhibitory effects on four human tumor cell lines (A549, SK-OV-3, SK-MEL-2, and HCT15) and a human normal cell line (HUVEC) using a sulforhodamine B (SRB) bioassay. Compounds 1 and 2 showed cytotoxicity against tumor cell lines (A549, SK-OV-3, SK-MEL-2, and HCT15) with IC 50 values ranging from 6.3 to 26.9 μM and exhibited lower activity against the normal cell line (HUVEC) with IC50 values ranging from 27.1 to 28.8 μM, suggesting selective toxicity among tumor and normal cells. © 2011 American Chemical Society. Source


Kim K.H.,Sungkyunkwan University | Moon E.,Gachon University | Kim S.Y.,Gachon University | Choi S.U.,Korea Research Institute of Chemical Technology | And 3 more authors.
Planta Medica | Year: 2013

A phytochemical investigation on the essential oil of Thuja orientalis resulted in the isolation and identification of three new sesquiterpenes, 3α-methoxy-4α-epoxythujopsane (1), Δ3,15-4β- epoxythujopsene (2), and Δ3,4-thujopsen-2,15-diol (3), together with eight known sesquiterpenoids (4-11). The structures of these new compounds were elucidated based on spectroscopic data analyses including extensive 2D-NMR data and HR-ESIMS. The full assignments of 1H and 13C NMR chemical shifts for thujopsadiene (4) were obtained by 2D-NMR for the first time. All compounds (1-11) showed antiproliferative activities against the SK-OV-3 and SK-MEL-2 cell lines with IC50 values of 5.85-28.64 μM. In addition, compounds 1, 3, 4, 7, 8, and 9 significantly inhibited nitric oxide production in lipopolysaccharide-activated BV-2 cells with IC50 values of 3.93-17.85 μM without cell toxicity. © 2013 Georg Thieme Verlag KG Stuttgart New York. Source

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