An improved synthesis of the key intermediates (3 and 8) for the synthesis of beta-hydroxywybutines [[R-(R*,S*)]- and [S-(R*,R*)]-4], the most probable structures for the minor base from rat liver tRNA(Phe), has been achieved by the Wittig reaction between 1-benzyl-7-formylwye (1) and the phosphorane derived from (R)-2-[(methoxycarbonyl)amino]-3-(triphenylphosphonio)propanoate (10), followed by methylation
改进的关键
中间体(3和8)的合成方法,用于合成最大的β-羟基酪
丁胺[[R-(R *,S *)]-和[S-(R *,R *)]-4]。 1-
苄基-7-甲酰基wye(1)和衍生自(R)-2-[((甲
氧羰基)
氨基]-的
磷烷之间的Wittig反应已实现了大鼠肝脏tRNA(Phe)中次要碱基的可能结构3-(
三苯基膦酰基)
丙酸酯(10),然后进行
甲基化,OsO4
氧化,并在
吡啶存在下用COCl2进行环缩合。确定[R-(R *,S *)]的光学纯度所需要的外消旋体形式的β-羟基
丁酸[[R *,S *)-和(R *,R *)-4]。 -和[S-(R *,R *)]-4通过手性HPLC,通过环
碳酸酯3的热解,然后NaBH4还原和催化
氢解,方便地制备。[R-(R *,S *)]-和[S-(R *,