An Enantiospecific Synthesis of the C-21–C-37 Segment of the Aglycon of Amphotericin B
作者:Mitsuhiro Kinoshita、Hitoshi Takami、Masato Taniguchi、Tetsuro Tamai
DOI:10.1246/bcsj.60.2151
日期:1987.6
3-Deoxy-1,2-O-isopropylidene-3-C-methyl-α-D-allofuranose was stereoselectively converted into 3,5-dideoxy-4-O-(methoxymethyl)-3,5-di-C-methyl-6-O-pivaloyl-L-talose ethylene dithioacetal (31) via 3,5-dideoxy-4-O-(methoxymethyl)-3,5-di-C-methyl-L-talopyranuro-6,2-lactone ethylene dithioacetal (24) in 10 steps (23.6% overall yield). Desulfurization [Raney Ni W-4, 92% yield] of 31 followed by three-step
3-Deoxy-1,2-O-isopropylidene-3-C-methyl-α-D-allofuranose 立体选择性转化为 3,5-dideoxy-4-O-(甲氧基甲基)-3,5-di-C-methyl -6-O-pivaloyl-L-talose ethylene dithioacetal (31) via 3,5-dideoxy-4-O-(甲氧基甲基)-3,5-di-C-methyl-L-talopyranuro-6,2-lactone 乙烯二硫缩醛 (24) 分 10 步(总收率 23.6%)。31 脱硫 [Raney Ni W-4, 92% 产率],然后三步转化(91% 产率)得到 2,4,6-三脱氧-5-O-(二乙基异丙基甲硅烷基)-3-O-(甲氧基甲基)- 2,4-二-C-甲基-L-altrose,通过使用(2E,4E)-6-(二甲氧基膦基)-2,4-己二烯酸甲酯两次烯化得到目标化合物,全反式-己烯醛4