Berkowitz David B, Chisowa Esmort, McFadden Jill M
Department of Chemistry, University of Nebraska, Lincoln, NE 68588-0304.
Tetrahedron. 2001 Jul 23;57(30):6329-6343. doi: 10.1016/S0040-4020(01)00499-9.
A pair of diastereomeric (4S,5S)- and (4S,5R)-4-methoxycarbonyl-5-phenylselenomethyl-2-phenyl oxazolines, derived from L-vinylglycine, serve as precursors 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 2-iodovinyl branch) may be exploited to access novel quaternary, L- and D-β,γ-unsaturated amino acids via a range of transition metal-mediated cross coupling reactions.
一对由L-乙烯基甘氨酸衍生而来的非对映异构的(4S,5S)-和(4S,5R)-4-甲氧基羰基-5-苯基硒甲基-2-苯基恶唑啉,分别作为受保护的季铵型L-和D-α-(2-三丁基锡基)乙烯基氨基酸的前体,反应分三步进行{(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的相互转化}。标题化合物可脱锡生成相应的游离季铵型L-和D-乙烯基氨基酸。或者,2-锡基乙烯基α-支链(或衍生物2-碘乙烯基支链)可用于通过一系列过渡金属介导的交叉偶联反应获得新型季铵型L-和D-β,γ-不饱和氨基酸。