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本文报道以青蒿酸(2)为原料合成了一些含羟基的青蒿倍半萜内酯差向异构体9与10、11与12、13与14。其中9已从青蒿中分离到。 相似文献
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青蒿[1]Artemisia annua L.又名香蒿,为菊科植物青蒿或黄花蒿的全草.分布辽宁、河北、山东、山西、江苏、广东等地.青蒿在我国各地均有大量野生,资源丰富,本植物的根(青蒿根),果实(青蒿籽)均可供药用,青蒿具有抗疟、抗血吸虫、解热、镇痛及退虚热、和胃止痛等功效.青蒿的主要成分有苦味质、挥发油和青蒿碱、维生素A等.为探讨其挥发油的成分,我们对青蒿全草进行挥发油的提取,并用GC-MS进行测定分析,从中鉴定出44个化合物. 相似文献
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青蒿甲素(1)与抗疟有效成分青蒿素(2)共存于植物青蒿之中,它是一个新型的失碳倍半萜内酯,其结构已经测定,本文报道它的合成. 青蒿酸甲酯(3)用间氯过苯甲酸氧化,得4α,5α-环氧青蒿酸甲酯(4).4在二氯甲烷-吡啶中进行臭氧化,得α-酮酸酯(5),产率88%.5用碱性过氧化氢氧化降解,得羟基内酯(6),产率92%.6用POCl_3-吡啶脱水,即得1,m.p.151~153℃,[α]_~(10)-40°(c 0.57,CHCl_3),与天然品的混合熔点不降低,其IR、~1H NMR、MS、TLC R_1值和GC亦完全一致. 在推定6的结构时,我们曾将5的碱性过氧化氢氧化反应分步进行.先用碱水解,结果得 相似文献
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Using arteannuin B (2) isolated from Artemisia annua L.,a number of chemical transformations have been carried out, i.e., catalytic hydrogenation of 2 to give a mixture of 5, 6 and 7, reaction of 6 with boron trifluoride etherate to give 8 and 9, saponification of 6 with potassium hydroxide and deoxygenation of 2, 6 and 7 with iron pentacarbonyl to give 18, 4 and 3, respectively. 相似文献
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Arteannuin E was synthesized from methyl β-epoxy arteannuinate by treatment with formic acid followed by hydrolysis and lactonization. Methyl α-epoxy arteannuinate or methyl α-epoxy dihydroarteannuinate treated with formic acid did not produce the trans-diaxial product. Arteannuin E (1) and arteannuin F (2) exist together with the arteannuin (3) in Artemisia annua L.1 The structures were determined1 and 2 was synthesized.2 The structure difference lies in the different fusion of their lactone rings. In this paper we will report the synthesis of 1 and the epoxy fission reaction of the methyl α-epoxy arteannuinate (4). 相似文献
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Arteannuin (1), a new sesquiterpene lactone containing a peroxide group, is the antimalarial active principle isolated from Artemisia annua L. Deoxyarteannuin (2) occurs in the same plant and was isolated as a metabolite from the urine of patients treated with arteannuin. We now report a stereocontrolled synthesis of these two naturally occurring sesquiterpene lactones starting from arteannuic acid (5) by the reaction sequence as shown in Scheme 2 (see Chinese Text). Irradiation of the methanolic solution of the key intermediate 3 in the resence of oxygen and a sensitizer (Rose Bangal) with 200 W high pressure mercury lamp followed by acid treatment gave 1 in 28% yield (2 steps), m.p. 151-153`c, 相似文献