Asymmetric Synthesis of Nidulalin A and Nidulaxanthone A: Selective Carbonyl Desaturation Using an Oxoammonium Salt
作者:Kaijie Ji、Richard P. Johnson、James McNeely、Md Al Faruk、John A. Porco
DOI:10.1021/jacs.3c13864
日期:2024.2.21
expedite the synthesis of nidulalin A and study the proposed dimerization, we developed methodology involving the use of allyl triflate for chromone ester activation, followed by vinylogous addition, to rapidly forge the nidulalin A scaffold in a four-step sequence which also features ketone desaturation using Bobbitt’s oxoammonium salt. An asymmetric synthesis of nidulalin A was achieved using acylative
Nidulaxanthone A 是一种二聚二氢氧杂蒽酮天然产物,于 2020 年从曲霉属 sp中分离出来。在结构上,该化合物具有前所未有的七环 6/6/6/6/6/6/6 环系统,这对于天然呫吨酮二聚体来说是不常见的。在生物合成上,nidulaxanthone A 源自单体 nidulalin A 通过立体选择性 Diels-Alder 二聚化。为了加速 Nidulalin A 的合成并研究所提出的二聚化,我们开发了一种方法,包括使用三氟甲磺酸烯丙酯进行色酮酯活化,然后进行插烯加成,以四步顺序快速锻造 Nidulalin A 支架,该支架还具有酮去饱和作用使用博比特的氧铵盐。使用手性外消旋 2 H -nidulalin A 的酰化动力学拆分 (AKR) 实现了 nidulalin A 的不对称合成。使用无溶剂热解条件实现了对映体富集的 nidulalin A 向 nidulaxanthone