Gandy Michael N, Piggott Matthew J
School of Biomedical, Biomolecular and Chemical Sciences, The University of Western Australia, Crawley, WA, Australia.
J Nat Prod. 2008 May;71(5):866-8. doi: 10.1021/np070582z. Epub 2008 Mar 8.
The first total synthesis of the azaanthracene kalasinamide (1) is described, and the discrepancy in the reported (13)C NMR data and melting points for the natural product from two different sources is resolved. Kalasinamide is prone to autosensitized photooxidation, in solution and in the solid state, to give the corresponding quinone, marcanine A (8). This transformation may be representative of a novel and more general step in the biosynthesis of (aza)anthraquinones. Through its ability to generate toxic singlet oxygen, kalasinamide may serve a protective role, defending the plant against predation and the invasion of microbial pathogens, following mechanical insult.
本文描述了氮杂蒽卡拉西酰胺（1）的首次全合成，并解决了来自两种不同来源的天然产物所报道的碳-13核磁共振数据和熔点之间的差异。卡拉西酰胺在溶液和固态中均易于发生自敏化光氧化反应，生成相应的醌类化合物马卡宁A（8）。这种转化可能代表了（氮杂）蒽醌生物合成中一个新颖且更普遍的步骤。由于卡拉西酰胺能够产生有毒的单线态氧，在机械损伤后，它可能起到保护作用，保护植物免受捕食和微生物病原体的入侵。
