Rana S S, Matta K L
Carbohydr Res. 1986 Sep 1;152:195-203. doi: 10.1016/s0008-6215(00)90299-4.
Methyl 3,4,6-tri-O-benzyl-2-O-[6-O-(tert-butyldiphenylsilyl)-alpha-D- mannopyranosyl]-alpha-D-mannopyranoside (2) was synthesized by treatment of methyl 3,4,6-tri-O-benzyl-2-O-alpha-D-mannopyranosyl-alpha-D-mannopyranoside with tert-butylchlorodiphenylsilane in the presence of imidazole. Isopropylidenation, followed by oxidation with pyridinium chlorochromate, and stereoselective reduction with sodium borohydride, converted 2 into methyl 3,4,6-tri-O-benzyl-2-O-[6-O-(tert-butyldiphenylsilyl)-2,3-O-isopro pylidene- alpha-D-talopyranosyl]-alpha-D-mannopyranoside (5). Treatment of 5 with a molar solution of tetrabutylammonium fluoride in dry oxolane produced a diol which, on O-de-isopropylidenation followed by catalytic hydrogenolysis, afforded the disaccharide glycoside methyl 2-O-alpha-D-talopyranosyl-alpha-D-mannopyranoside. Synthesis of methyl 3-O-alpha-D-talopyranosyl-alpha-D-mannopyranoside was accomplished by a similar reaction-sequence. The structures of the final disaccharides, and of various other intermediates, were established by 1H- and 13C-n.m.r. spectroscopy.
在咪唑存在下,用叔丁基氯二苯基硅烷处理3,4,6-三-O-苄基-2-O-α-D-甘露吡喃糖基-α-D-甘露吡喃糖苷甲酯,合成了3,4,6-三-O-苄基-2-O-[6-O-(叔丁基二苯基甲硅烷基)-α-D-甘露吡喃糖基]-α-D-甘露吡喃糖苷甲酯(2)。通过亚异丙基化,接着用氯铬酸吡啶鎓氧化,并用硼氢化钠进行立体选择性还原,将2转化为3,4,6-三-O-苄基-2-O-[6-O-(叔丁基二苯基甲硅烷基)-2,3-O-亚异丙基-α-D-塔罗吡喃糖基]-α-D-甘露吡喃糖苷甲酯(5)。用四丁基氟化铵在干燥的四氢呋喃中的摩尔溶液处理5,得到一种二醇,该二醇在O-脱亚异丙基化,然后催化氢解后,得到二糖糖苷2-O-α-D-塔罗吡喃糖基-α-D-甘露吡喃糖苷甲酯。3-O-α-D-塔罗吡喃糖基-α-D-甘露吡喃糖苷甲酯的合成通过类似的反应序列完成。最终二糖和各种其他中间体的结构通过1H-和13C-核磁共振光谱确定。