几种国产药用紫草中萘醌色素的分析

从新疆软紫草石油醚提取物中分离出六个化合物。根据其理化常数、光谱数据(MS,IR,¹HNMR)鉴定为去氧紫草素(deoxyshikonin),β,β-二甲基丙烯酰阿卡宁(β,β-dimethylacryalkannin),乙酰紫草素(acetylshikonin),β-乙酰氧基异戊酰阿卡宁(β-acetoxyisovalerylalkannin),紫草素(shikonin),β-羟基异戊酰阿卡宁(β-hydroxyisovalerylalkannin)。用高效薄层层析扫描方法,分析了我国不同种类、不同产地的紫草根,均含萘醌类色素,但种间含量差异甚大。

ANALYSIS OF NAPHTHAQUINONE PIGMENTS IN SOME CHINESE MEDICINAL "ZICAO" ,ARNEBIA EUCHROMA

Six naphthaquinone pigments have been isolated from the root of Arnebia euchroma. They were identified as deoxyshikonin (Ⅰ), β, β-dimethylacrylalkannin (Ⅱ), acetylshikonin (Ⅲ), β-acetoxyisovalerylalkannin (Ⅳ), shikonin (Ⅴ) and β-hydroxyisovalerylalkannin (Ⅵ) based on spectral data (MS, IR, ¹HNMR), Compounds Ⅳ and Ⅵ were found for the first time from this plant.Five kinds of more widely used "Zicao", viz. Lithospermum erythrorhizon, Arnebia euehroma, A. guttata, Onosrma paniculatum and O. hookeri, were analysed by means of a quantitative HPTLC scanning method and found that the total contents of naphthaquinone pigments varied in accordance with species and localities of the species analysed, which ranged 0.39～1.80% in L. erythrorhizon, 2.13～6.73% in A. euehroma and 0.13～0.81% in A. guttata, O. paniculatum and O.hookeri. The result appeared to be parallel with the traditional criterion of qualification and evaluation.The present study revealed that all the above mentioned "Zicao" contained β, β-dimethylaerylalkannin and acetylshikonin as the main constituents and consequently they are phylogenetically closely related.