Synthesis of .alpha.-methyl 1',2'-dideoxycellobioside: a novel C-disaccharide
摘要:
Bromonium ion induced 6-endo-trig cyclizations of E olefine derived from D-arabinose provide a stereoselective route to 2'-deoxyglucono-beta-C-glycosides. Use of delta-alkenols containing allylic isopropylidenes (i.e., 1) prevents formation of furan products due to the highly strained transition state necessary for formation of the trans [3.3.0] bicyclic systems. Because the exo-anomeric carbon is not involved in the cyclization, previously established stereocenters at this carbon are left intact. Application of this methodology to the synthesis of alpha-methyl 1',2'-dideoxycellobioside (22) is presented. The restricted rotation about the bond connecting the two sugars affords a unique staggared conformation of the disaccharide.
Synthesis of .alpha.-methyl 1',2'-dideoxycellobioside: a novel C-disaccharide
摘要:
Bromonium ion induced 6-endo-trig cyclizations of E olefine derived from D-arabinose provide a stereoselective route to 2'-deoxyglucono-beta-C-glycosides. Use of delta-alkenols containing allylic isopropylidenes (i.e., 1) prevents formation of furan products due to the highly strained transition state necessary for formation of the trans [3.3.0] bicyclic systems. Because the exo-anomeric carbon is not involved in the cyclization, previously established stereocenters at this carbon are left intact. Application of this methodology to the synthesis of alpha-methyl 1',2'-dideoxycellobioside (22) is presented. The restricted rotation about the bond connecting the two sugars affords a unique staggared conformation of the disaccharide.
Synthesis of .alpha.-methyl 1',2'-dideoxycellobioside: a novel C-disaccharide
作者:Robert W. Armstrong、Bradley R. Teegarden
DOI:10.1021/jo00029a024
日期:1992.1
Bromonium ion induced 6-endo-trig cyclizations of E olefine derived from D-arabinose provide a stereoselective route to 2'-deoxyglucono-beta-C-glycosides. Use of delta-alkenols containing allylic isopropylidenes (i.e., 1) prevents formation of furan products due to the highly strained transition state necessary for formation of the trans [3.3.0] bicyclic systems. Because the exo-anomeric carbon is not involved in the cyclization, previously established stereocenters at this carbon are left intact. Application of this methodology to the synthesis of alpha-methyl 1',2'-dideoxycellobioside (22) is presented. The restricted rotation about the bond connecting the two sugars affords a unique staggared conformation of the disaccharide.