AbstractA novel purple‐red pigment from the plant genus of Allium (onions, leeks), subgenus Melanocrommyum (drumstick onions), is described. Because of this pigment, which reminds of blood, some species of the subgenus Melanocrommyum are used in Southwest and Central Asia as herbal medications, as spices or as vegetables. A proposal for the formation of this structure is provided, which is the first example of a tetrathiaporphyrin in nature. The described substance shows low stability towards thermal stress, light and oxidant; additionally, its symmetric nature made structural elucidation a challenge. It could be shown that, contrary to previous reports, the structure of the red pigment is that of a tetrathiaporphyrin. Full structure elucidation was only possible by X‐ray crystallography and total synthesis of the intended molecule. Further on, the newly discovered red pigment was used for the modification of nanoparticles and monitoring its polymerization events using SPR.
摘要 描述了一种来自葱属(洋葱、韭菜)植物 Melanocrommyum 亚属(鼓槌洋葱)的新型紫红色色素。由于这种色素让人联想到血液,Melanocrommyum 亚属的一些物种在西南亚和中亚被用作草药、香料或蔬菜。本文提出了这种结构的形成原因,这是自然界中首个四硫代卟啉的实例。所描述的物质对热应力、光和氧化剂的稳定性较低;此外,它的对称性也给结构阐释带来了挑战。结果表明,与之前的报道相反,这种红色素的结构是一种四硫代卟啉。只有通过 X 射线晶体学和对目标分子的全合成,才能完全阐明其结构。此外,新发现的红色素还被用于纳米颗粒的改性,并利用 SPR 技术监测其聚合反应。