Iromycins: A New Family of Pyridone Metabolites from <i>Streptomyces</i> sp. II. Convergent Total Synthesis
作者:Heydar Shojaei、Zhen Li-Böhmer、Paultheo von Zezschwitz
DOI:10.1021/jo070327j
日期:2007.7.1
The total synthesis of iromycin A (1a), a microbial metabolite combining a novel structure with an interesting biological activity as a NO synthase inhibitor, was accomplished using a flexible and highly convergent approach. Thus, the ring fragment was prepared as 6-bromomethylpyrone 27 by acylation of the respective β-ketoester 13 and subsequent lactonization of the thus-obtained β,δ-diketoester 11
伊洛霉素A(1a)是一种微生物代谢产物,具有新颖的结构和作为NO合酶抑制剂的有趣生物活性,可以通过灵活且高度收敛的方法完成总合成。因此,通过将各自的β-酮酸酯13酰化并且随后将如此获得的β,δ-二酮酸酯11内酯化,然后将6-甲基溴化,将环片段制备为6-溴甲基吡喃酮27。另外,有效地制备了不饱和侧链作为末端炔烃34,然后将其碳铝化以提供烯基二甲基烷烃35。。使用镍,钯和铜催化剂对这两个片段的组装进行了彻底的研究,但仅在形成相应的烯基三烷基丙氨酸锂之后,在没有任何过渡金属的情况下才成功。然后用液氨处理偶联产物41,完成了总合成,在最长线性序列的九个步骤中,总产率为18%。