AK-toxin I, a host-specific toxin to Japanese pear (Pyrus serotina), was synthesized as its methyl ester from three precursor fragments: conjugated diene-carboxylic acid, chiral epoxyalcohol and β-methylphenylalanine. The epoxyalcohol fragment was derived from D-fructose, in which effective homologation of the hemiacetal carbon to alkyne by using dimethyl 1-diazo-2-oxopropylphosphonate was the key
AK-毒素I是日本梨(Pyrus serotina)的一种宿主特异性毒素,是由其三个前体片段(共轭二烯-
羧酸,手性环氧醇和β-甲基苯基丙
氨酸)合成的甲酯形式的。环氧醇片段衍生自
D-果糖,其中通过使用1-重氮-2-氧代
丙基膦酸二甲酯使
半缩醛碳有效同化为
炔烃是关键反应。通过重复的Wittig反应制备二烯-
羧酸片段,并通过Stille反应将其与环氧醇片段结合。用立体
化学纯的β-甲基苯基丙
氨酸片段酯化合并的产物,得到目标化合物。该方法用于制备tri标记的AK毒素I的甲酯,其比放射性为213 GBq / mmol。