Efficient synthesis of the deoxysugar part of versipelostatin by direct and stereoselective glycosylation and revision of the structure of the trisaccharide unit.
Efficient synthesis of the deoxysugar part of versipelostatin (VST) was achieved by direct and stereoselective glycosylation of the reduced VST aglycon. Activation of 2-deoxyglycosyl imidate with IBr under basic conditions enables alpha-selective glycosylation of beta-2-deoxylglycosides without anomerization. Comparison of the synthetic and natural VST products using NMR indicates that versipelostatin has a beta-D-digitoxose-(1,4)-alpha-L-oleandrose-(1,4)-beta-D-digitoxose trisaccharide. In addition, results of a biological assay indicate that the deoxyoligosaccharide unit of the synthetic glycoside was important for biological activity of the compound.
Department of Applied Chemistry, Graduate School of Science and Engineering, Tokyo Institute of Technology, 2-12-1-S1-35 Ookayama, Meguro, Tokyo 152-8552, Japan. thiroshi@apc.titech.ac.jp
Hiroshi
H
Tanaka
Atsushi
A
Yoshizawa
Shuhei
S
Chijiwa
Jun-ya
JY
Ueda
Motoki
M
Takagi
Kazuo
K
Shin-ya
Takashi
T
Takahashi
D045744:Cell Line, Tumor; D003837:Deoxy Sugars / Q000138:chemical synthesis* / Q000737:chemistry; D006031:Glycosylation; D006367:HeLa Cells; D006801:Humans; D018942:Macrolides / Q000138:chemical synthesis / Q000737:chemistry* / Q000633:toxicity; D008968:Molecular Conformation; D009844:Oligosaccharides / Q000138:chemical synthesis / Q000737:chemistry* / Q000633:toxicity; D013237:Stereoisomerism; D014312:Trisaccharides / Q000138:chemical synthesis / Q000737:chemistry*
D003837:Deoxy Sugars; D018942:Macrolides; D009844:Oligosaccharides; D014312:Trisaccharides; C490154:versipelostatin