摘要:
The novel linker 4 was synthesized in three steps front hex-5-enyldimethylchlorosilane and glycosylated with 2,3,4,6-tetra-O-benzoyl-alpha-D-galactopyranosyl trichloroacetimidate to give the corresponding linker beta-glycoside 5 (77%). Treatment of 5 with acetic anhydride and BF3 . OEt2 gave 1-O-acetyl-2,3,4,6-tetra-O-benzoyl-beta-D-galactose (similar to 90%), devoid of the alpha-anomer. (C) 1997 Elsevier Science Ltd.