388570-22-7Relevant academic research and scientific papers
Stereoselective synthesis and structure elucidation of spiro-ketodisaccharides
Li, Xiaoliu,Takahashi, Hideyo,Ohtake, Hiro,Shiro, Moto,Ikegami, Shiro
, p. 8053 - 8066 (2001)
Cycloglycosylation of 3,4,5,7-tetra-O-benzyl-α-D-hept-2-ulopyranoses (2a-c) was carried out stereoselectively under the catalysis of Lewis acid to afford two spiro-cyclodisaccharides 3a-c and 4a-c in good yields. The reaction provided the kinetic products 3a-c or the thermodynamic products 4a-c as the predominant products under different conditions, respectively. The unprotected disaccharides 5a-c and 6a-c and the acetylated derivatives 7a-c and 8a-c were prepared by catalytic hydrogenation and followed by acetylation. The structures of compounds 4a-c, 6a-c and 8a-c were confirmed to be α,β-anomeric configuration with chair-chair-chair form for the tri-cycles based on the X-ray crystallographic analysis of 6a-c. The α,α-anomeric configurations of compounds 3a-c, 5a-c and 7a-c were determined based on the measurements of the three bond coupling constants 3JC,H between the C-1 and the H-3 of 7a-c.
