Studies on the Preparation of Bioactive Lignans by Oxidative Coupling Reaction. IV. Oxidative Coupling Reaction of Methyl (E)-3-(3,4-Dihydroxy-2-methoxyphenyl)propenoate and Lipid Peroxidation Inhibitory Effects of the Produced Lignans.
作者:Shirou MAEDA、Hiroshi MASUDA、Takashi TOKOROYAMA
DOI:10.1248/cpb.43.84
日期:——
The oxidative coupling reaction of the hydroxycinnamate 11 derived from daphnetin has been investigated. The reaction with silver oxide afforded, after acetylation, a dihydrobenzofuran derivative 17 and a benzodioxane derivative 16a as major products accompanied with a small amount of a bis(benzylidene) succinate 18 and a dihydronaphthalene 19, while the oxidation with iron(III) chloride gave the dihydronaphthalene derivative 20 corresponding to 19. The reaction with potassium hexacyanoferrate(III) and Na2CO3 produced, after acetylation, 16a and 19 in lower yields. The propensity for product formation in the reaction of 11 is discussed in relation to data for the reactions of hydroxycinnamate derivatives studied so far.The obtained compounds were tested for inhibitory effects on lipid peroxidation in rat brain homogenate and rat liver microsomes. In the rat brain homogenate the five compounds showed inhibitory activity more potent than that of idenbenone. Compounds 17 and 20 were then tested in rat liver microsomes, and found to be more potent than schizotenuin A and much more potent than (±)-α-tocopherol.
研究了从水飞蓟素中提取的羟基肉桂酸 11 的氧化偶联反应。与氧化银反应,乙酰化后的主要产物是二氢苯并呋喃衍生物 17 和苯并二噁烷衍生物 16a,以及少量双(亚苄基)琥珀酸酯 18 和二氢萘 19,而与氯化铁(III)氧化,则得到与 19 相对应的二氢萘衍生物 20。与六氰合铁酸钾(III)和 Na2CO3 反应,乙酰化后生成 16a 和 19,但产量较低。我们结合迄今为止研究的羟基肉桂酸酯衍生物的反应数据,讨论了 11 反应中生成产物的倾向。在大鼠脑匀浆中,这五种化合物显示出比茚二酮更强的抑制活性。然后,在大鼠肝脏微粒体中对化合物 17 和 20 进行了测试,结果发现它们比五味子素 A 更有效,比(±)-α-生育酚更有效。