Ghosal S, Sharma P V, Chaudhuri R K, Bhattacharya S K
J Pharm Sci. 1975 Jan;64(1):80-3.
The whole plant of Swertia purpurascens Wall. (Gentianaceae) has been shown to contain five tetraoxygenated and three pentaoxygenated zanthones. These are identified as 1,5,8-trihydroxy-3-methoxyxanthone, 1,3,8-trihydroxy-5-methoxyzanthone, 1-hydroxy-3,7,8-trimethoxyxanthone, 1,3,7,8-tetrahydroxyxanthone, 1,3,5,8-tetrahydroxyxanthone, and 1-hydroxy-3,4,7,8-tetramethoxyxanthone by chemical and spectral evidence. Additionally, the crude mixture of natural xanthones has been shown to include two partially emthylated pentaoxygenated xanthones as minor entities, which yield 1-hydroxy-3,4,7,8-tetramethoxyxanthone and 1-hydroxy-3,4,5,8-tetramethoxyxanthone on methylation. This is the first time that pentaoxygenated xanthones have been found in a member of the genus Swertia. 1-Hydroxy-3,4,7,8-tetramethoxyxanthone was previously known only as a synthetic compound. The total xanthones of S. purpurascens produce significant CNS stimulant actions, consistent with some therapeutic uses of the plant extract in the Indian system of medicine. The chemotaxonomic significance of the cooccurrence of various biogenetically related chemical characters in a single plant species is appraised.
紫红獐牙菜（龙胆科）的全株已被证明含有五种四氧化态和三种五氧化态的呫吨酮。通过化学和光谱证据，这些化合物被鉴定为1,5,8 - 三羟基 - 3 - 甲氧基呫吨酮、1,3,8 - 三羟基 - 5 - 甲氧基呫吨酮、1 - 羟基 - 3,7,8 - 三甲氧基呫吨酮、1,3,7,8 - 四羟基呫吨酮、1,3,5,8 - 四羟基呫吨酮以及1 - 羟基 - 3,4,7,8 - 四甲氧基呫吨酮。此外，天然呫吨酮的粗混合物已被证明含有两种部分甲基化的五氧化态呫吨酮作为次要成分，它们在甲基化后产生1 - 羟基 - 3,4,7,8 - 四甲氧基呫吨酮和1 - 羟基 - 3,4,5,8 - 四甲氧基呫吨酮。这是首次在獐牙菜属的一个成员中发现五氧化态呫吨酮。1 - 羟基 - 3,4,7,8 - 四甲氧基呫吨酮以前仅作为一种合成化合物为人所知。紫红獐牙菜的总呫吨酮具有显著的中枢神经系统兴奋作用，这与该植物提取物在印度医学体系中的一些治疗用途一致。本文评估了单一植物物种中各种生物合成相关化学特征共存的化学分类学意义。
