which is an antipode of the component of potent antifungal echinocandins, from (5)-Garner aldehyde (2a) has been established. The key step is chromium(II) chloride-mediated coupling reactions with crotyl bromide giving homoallyl alcohols (4a) and (4a') in a ratio of 83:17.
已确定由 (5)-Garner 醛 (2a) 有效合成 (2R,4R,4R)-3-羟基-4-甲基脯
氨酸 (la),它是强效抗真菌棘白菌素成分的对映体。关键步骤是
氯化
铬 (II) 介导的与
巴豆基
溴的偶联反应,以 83:17 的比例生成高
烯丙醇 (4a) 和 (4a')。