作者:Eduardo V. Mercado-Marin、Pablo Garcia-Reynaga、Stelamar Romminger、Eli. F. Pimenta、David K. Romney、Michael W. Lodewyk、David E. Williams、Raymond J. Andersen、Scott J. Miller、Dean J. Tantillo、Roberto G. S. Berlinck、Richmond Sarpong
DOI:10.1038/nature13273
日期:2014.5
Many natural products that contain basic nitrogen atomsâfor example alkaloids like morphine and quinineâhave the potential to treat a broad range of human diseases. However, the presence of a nitrogen atom in a target molecule can complicate its chemical synthesis because of the basicity of nitrogen atoms and their susceptibility to oxidation. Obtaining such compounds by chemical synthesis can be further complicated by the presence of multiple nitrogen atoms, but it can be done by the selective introduction and removal of functional groups that mitigate basicity. Here we use such a strategy to complete the chemical syntheses of citrinalinâB and cyclopiamineâB. The chemical connections that have been realized as a result of these syntheses, in addition to the isolation of both 17-hydroxycitrinalinâB and citrinalinâC (which contains a bicyclo[2.2.2]diazaoctane structural unit) through carbon-13 feeding studies, support the existence of a common bicyclo[2.2.2]diazaoctane-containing biogenetic precursor to these compounds, as has been proposed previously. Natural products citrinalinâB and cyclopiamineâB, which contain basic nitrogen atoms that are susceptible to oxidation during synthesis, can be synthesized by the selective introduction and removal of functional groups. This paper reports the first syntheses of the natural products citrinalin B and cyclopiamine B. And as a by-product of this work, the authors propose a revision of the structure initially assigned to citrinalin B. The presence of nitrogen atoms in a target molecule can complicate its synthesis because of nitrogen's basicity and susceptibility to oxidation. This can be circumvented by the selective introduction and removal of functional groups that mitigate basicity. The prenylated indole alkaloids citrinalin B and cyclopiamine B were produced using a refinement of the technique, opening up a class of compounds that includes therapeutics such as quinine and morphine to synthetic chemistry.
许多含有碱性氮原子的天然产物(例如吗啡和奎宁等生物碱)都具有治疗多种人类疾病的潜力。然而,由于氮原子的碱性和易氧化性,目标分子中氮原子的存在会使其化学合成复杂化。通过化学合成获得此类化合物会因多个氮原子的存在而变得更加复杂,但可以通过选择性地引入或去除可减轻碱性的官能团来实现。在这里,我们采用这种策略完成了枸橼醛âB 和环丙胺âB 的化学合成。除了通过碳-13 进料研究分离出 17-hydroxycitrinalinâB 和 citrinalinâC(含有双环[2.2.2]二氮杂环辛烷结构单元)之外,这些合成所实现的化学联系也支持了之前所提出的观点,即这些化合物存在一个共同的含有双环[2.2.2]二氮杂环辛烷的生物前体。 天然产物 citrinalinâB 和 cyclopiamineâB 含有碱性氮原子,在合成过程中容易被氧化,因此可以通过选择性地引入或去除官能团来合成。本文首次报道了天然产物枸橼酸苷 B 和环丙胺 B 的合成。作为这项工作的副产品,作者对最初分配给枸橼酸苷 B 的结构提出了修改意见。通过有选择性地引入或去除可减轻碱性的官能团,可以避免这一问题。通过对该技术的改进,制备出了前炔化吲哚生物碱 citrinalin B 和 cyclopiamine B,为化学合成开辟了一类化合物,其中包括奎宁和吗啡等治疗药物。