Stereocontrolled synthesis of quaternary β,γ-unsaturated amino acids: chain extension of d- and l-α-(2-tributylstannyl)vinyl amino acids
作者:David B Berkowitz、Esmort Chisowa、Jill M McFadden
DOI:10.1016/s0040-4020(01)00499-9
日期:2001.7
to protected, quaternary, l- and d-α-(2-tributylstannyl)vinyl amino acids, respectively, in three steps (i) alkylative side chain installation, (ii) eliminative ring-opening and (iii) vinyl selenide to vinyl stannane interconversion}. The title compounds may be protodestannylated to the corresponding free, quaternary l- and d-vinyl amino acids. Alternatively, the 2-stannylvinyl α-branch (or the derivative
一对非对映异构体 (4 S ,5 S )- 和 (4 S ,5 R )-4-甲氧基羰基-5-苯基硒代甲基-2-苯基恶唑啉,衍生自 L-乙烯基甘氨酸,作为受保护的季铵盐的前体。和d-α-(2-三丁基甲锡基)乙烯基氨基酸,分别在三个步骤(i)烷基化侧链安装,(ii)消除开环和(iii)乙烯基硒化物到乙烯基锡烷互变}。标题化合物可以被原脱甲烷基化为相应的游离的季铵l-和d-乙烯基氨基酸。或者,可以利用 2-甲锡烷基乙烯基 α-支链(或衍生物 2-碘乙烯基支链)通过一系列过渡金属介导的交叉偶联反应来获得新型季铵盐、L-和 d-β,γ-不饱和氨基酸。