Asymmetric syntheses of methyl N-Boc-2-deoxy-2-amino-l-erythroside, methyl N-Boc-2-deoxy-2-amino-d-threoside and methyl N-Boc-2,3-dideoxy-3-amino-l-arabinopyranoside
作者:Marta Brambilla、Stephen G. Davies、Ai M. Fletcher、Li Hao、Linlu Lv、Paul M. Roberts、James E. Thomson
DOI:10.1016/j.tet.2014.03.055
日期:2014.5
alternative synthesis of methyl N-Boc-2-deoxy-2-amino-l-erythroside was also developed, reliant on aminohydroxylation of an α,β-unsaturated ester bearing an acetal functionality at the γ-position, and this synthesis proceeded in five steps and 54% overall yield from acrolein diethyl acetal. This approach was extended to permit the synthesis of methyl N-Boc-2,3-dideoxy-3-amino-l-arabinopyranoside in six steps
的不对称合成甲基Ñ -Boc-2-脱氧-2-氨基-升-erythroside和甲基Ñ -Boc-2-脱氧-2-氨基- d -threoside具有从山梨酸而完成的,在六个和八个步骤,总收率分别为35%和13%。非对映选择性氨羟化叔丁基山梨酸可以访问两个非对映异构α羟基-β氨基γ,δ不饱和酯类。酯官能度的降低和双键的臭氧分解得到相应的醛,其仅以闭环(呋喃糖)形式存在。甲基的替代性合成Ñ -Boc-2-脱氧-2-氨基-升还开发了-赤藓糖苷,其依赖于在γ-位带有乙缩醛官能团的α,β-不饱和酯的氨基羟基化作用,该合成过程分五个步骤进行,丙烯醛二乙缩醛的总收率为54%。扩展了该方法以允许分六步合成甲基N -Boc-2,3-二脱氧-3-氨基-1-阿拉伯吡喃果糖苷,并且从3,3-二乙氧基丙酸乙酯的总产率为58%。