Synthesis of naturally occurring quinones

最大的一组天然色素是一组被称为醌的化合物。然而，尽管它们有明亮的黄色或红色，但它们对自然颜色的贡献相对较小。然而，它们在自然界中广泛存在，并且对于许多生命过程是必不可少的，因为它们容易参与生物氧化和还原反应（氧化还原过程）。因此，例如，泛醌是我们呼吸链中必不可少的电子转移剂。其他醌类天然产物也具有有效的生物活性，例如阿霉素，在英国是一线癌症化疗药物之一。醌类化合物的合成和研究具有重要的生物活性，因此，醌类化合物的合成和研究在世界范围内都是一个非常活跃的研究领域，对英国来说也是非常重要的。这项研究旨在寻找制造这些重要分子的新方法。选择了四种天然存在的醌（tridentoquinone、lanciaquinone、longithorone B和longithorone D）来说明所述方法。所有这些天然产物都具有不寻常的结构和生物活性。这些提议包括对一种古老反应的一些新的发展，即所谓的克莱森重排，它将被用来将必要的碳链引入分子中。这一点，再加上一个模仿自然界制造这种化合物的反应，将被用来获得三齿醌，一种以前从未合成过的分子。同样地，兰恰醌和长甲萘醌D以前从未被制造过，并且所提出的路线试图以富有想象力的新方式使用克莱森重排。

The largest group of naturally occurring pigments is a set of compounds known as quinones. However, despite their bright yellow or red colours, their contribution to natural colour is relatively small. Nevertheless, they are widespread in Nature and are essential for many life processes in that they readily participate in biological oxidation and reduction reactions (redox processes). Thus for example, the ubiquinones are the essential electron-transfer agents in our respiratory chain. Other quinone natural products also possess potent biological activity, doxorubicin, for example, being one of the front-line cancer chemotherapy treatments in the UK. The synthesis and study of quinones is therefore of immense importance given the biological activity associated with many such compounds, and hence it is an extremely active area of research worldwide, with considerable importance to the UK.The proposed research seeks to look at new ways of making these important molecules. Four naturally occurring quinones (tridentoquinone, lanciaquinone, longithorone B and longithorone D) have been chosen to illustrate the methods. All of these natural products have unusual structures and are biologically active. The proposals include some new developments of an old reaction, the so-called Claisen rearrangement, whereby it will be used to introduce the necessary carbon chains into the molecules. This, in combination with a reaction that mimics the way that Nature makes the compound, will be used to access tridentoquinone, a molecule that has not been synthesised before. Likewise, lanciaquinone and longithorone D have never been made previously, and the proposed routes attempt to use the Claisen rearrangement in imaginative new ways.