Keun Ho Chun | Researchain

Archive Network Publication Hotspot Collaboration

Hotspot

Bubble
[Coming Soon]

Cloud

Mosaic
[Coming Soon]

Tetrahedron Letters | 2001

A short synthesis of bicyclic sugar pyrimidine nucleosides from C-glycosides

Jonghoon Oh; Chung Ryul Lee; Keun Ho Chun

Abstract The C -glycosides were prepared from dichloroketene cycloaddition reaction to glycals and converted to bicyclic sugar nucleosides in good yields.

Synthetic Communications | 2002

A ONE-POT CONVENIENT PROCEDURE FOR THE SYNTHESIS OF C-GLYCOSIDE VIA CYCLOADDITION OF DICHLOROKETENE TO GLYCAL AND DECHLORINATION OF THE CYCLOADDUCT

Jonghoon Oh; Chung-Ryul Lee; Keun Ho Chun

ABSTRACT A convenient procedure for the synthesis of C-glycoside was developed via cycloaddition of dichloroketene, generated in situ, to glycal and dechlorination of the cycloadduct using zinc and acetic acid.

Tetrahedron Letters | 1998

Photoinduced one pot transformation of 2-phenyl-4-ethylidene-5(4H)-oxazolone and allylic alcohols to γ, δ-unsaturated N-benzoyl amides

Bong Sen Park; Chul Min Oh; Keun Ho Chun; Jong Ook Lee

Abstract Photolysis of 2-Phenyl-4-ethylidene-5(4H)-oxazolones in the presence of allylic alcohols resulted in a novel one-pot transformation to γ,δ-unsaturated N-benzoyl amides via decarbonylation, nucleophilic addition of allylic alcohols, photoinduced hydrogen transfer and the Claisen rearrangement.

Bioorganic & Medicinal Chemistry Letters | 2016

Discovery of ursolic acid prodrug (NX-201): Pharmacokinetics and in vivo antitumor effects in PANC-1 pancreatic cancer

Yeohong Yoon; Jee Woong Lim; Ji-Young Kim; Younggi Kim; Keun Ho Chun

The aim of our study was to develop ursolic acid (UA) prodrugs in order to overcome UAs weakness, which has an extremely low bioavailability. UA-medoxomil (NX-201), one of our UA prodrugs, showed an improved bioavailability about 200times better than UA in rodent model. According to in vivo test performed with PANC-1 xenograft SCID mouse model, tumor growth rate decreased dose-dependently and 100mg/kg dose of NX-201 had an anticancer effect comparable to gemcitabine. Most of all the combination of NX-201 (50mg/kg, po, daily) and gemcitabine (40mg/kg, iv, 2timesperweek) even reduced tumor size after three weeks.

Archives of Pharmacal Research | 2004

Synthesis of 2′-Azidoethyl Trisaccharide, α-D-Gal-(1→2)-6d-α-D-Altro-Hepp-(1→3)-(β-D-GlcNAc, an o-antigenic repeating unit of C.jejuni 0:23 and 0:36

Mikyung Yun; Shinsook Yoon; Youngsook Shin; Keun Ho Chun; Jeong E. Nam Shin

A trisaccharide, the O-antigenic repeating unit ofC. jejuni serotype 0:23 and 0:36, was synthesized as a 2′-azidoethyl glycoside by block addition of perbenzylated thiogalactoside donors to α-altroHepp-(1→3)-GlcNPhth disaccharide acceptor in presence of IDCP promoter. The αlinkedaltro heptopyranoside moiety in the glycosyl acceptor was effectively prepared bySwern oxidation of α-mannohepp-(1→3)-GlcNPhth disaccharide followed by mild reduction with NaCNBH3.

Bulletin of The Korean Chemical Society | 1998

Syntheses of Mannosidic Disaccharides from Derivatives of Ethylthio

Mikyung Yun; Youngsook Shin; Shinsook Yoon; Keun Ho Chun; J. E. Nam Shin

Bulletin of The Korean Chemical Society | 2004

\alpha

Shinsook Yoon; Youngsook Shin; Keun Ho Chun; Jeong E. Nam Shin

ChemInform | 2010

-D-Mannopyranoside

S. Yoon; H. G. Kim; Keun Ho Chun; Jeong E. Nam Shin

Bulletin of The Korean Chemical Society | 2008

Synthesis of GlcNAcp- β-(1→3)-Galp- α-(1→2)-6-deoxy-altroHepp- α-(1→O-propyl, an O-Antigenic Repeating Unit from C. jejuni O:23 and O:36

Ji-ah Choi; Jong Ook Lee; Man Soo Kim; Jeong E. Nam Shin; Keun Ho Chun

Bulletin of The Korean Chemical Society | 2002

4-Deoxy-Analogues of p-Nitrophenyl β-D-Galactopyranosides for Specificity Study with β-Galactosidase from Escherichia coli.

Mikyung Yun; Keun Ho Chun; Jeong E. Nam Shin; Jonghoon Oh

Explore More