Organofluorine compounds and fluorinating agents. Part 11. Glycosyl fluorides from acetal-protected sugars
作者:Ralf Miethchen、Torsten Gabriel
DOI:10.1016/0022-1139(93)02938-b
日期:1994.4
2,3:5,6-di-O-isopropylidene-d-manno-furanoside (15) with simultaneous conversion into the corresponding acetylated glycosyl fluorides (8, 12, 16). The second acetal function in 11 and 15 is not cleaved by the weakened HF medium. 2-O-Benzyl-protected sugars such as methyl 3,5,6-tri-O-methyl-2-O-benzyl-d-glucofuranoside (13) react intramolecularly in the presence of HF/nitromethane/acetic anhydride to
2- ø - (2-乙酰氧基乙基)-3,4,6三- ö甲基α-d葡糖基氟化物(5)通过1,2-的部分切割得到ö -ethanediyl-β-D-通过HF /硝基甲烷/乙酸酐体系在糖苷位置上的吡喃葡萄糖衍生物4。相同的介质允许选择性的1,2-异亚丙基函数的α-d-glucofuranosides裂解(7,11)和5,6-的Ó在乙酰2,3-异亚丙基组:5,6-二- ö异亚丙基- d甘露-呋喃糖苷(15)与同时转换成相应的乙酰化的糖基氟化物(8,12,16)。弱化的HF介质不会裂解11和15中的第二个乙缩醛功能。2- ø苯甲基保护的糖,如甲基-3,5,6-三- ö甲基-2- ö苄基d-glucofuranoside(13)在HF的存在下反应,在分子内/硝基甲烷/乙酸酐以形成环状C-糖苷(14)。