Palladium(II)-catalyzed olefin-coupling reactions of kainic acid: effects of substitution on the isopropenyl group on receptor binding
作者:Gregory A. Conway、Joon Sup Park、Linda Maggiora、Mathias P. Mertes、Noemi Galton、Elias K. Michaelis
DOI:10.1021/jm00367a010
日期:1984.1
accomplished by treatment with an aromatic amine, palladium(II) acetate, and tert-butyl nitrite. Substitution of the allylic methyl group of 3 was accomplished by conversion to the pi-(allyl)palladium complex (5) which, on subsequent treatment with the carbanions of tert-butyl acetoacetate or phenylthioacetone, gave the alkylated products. Both the (Z)- and (E)-3-nitrophenyl derivatives (8a,b) of kainic
发现两个钯催化的碳-碳键形成反应可用于修饰受保护的含有空间位阻异丙烯基的氨基酸衍生物。通过用芳族胺,乙酸钯(II)和亚硝酸叔丁酯处理来完成N-(乙氧基羰基)海藻酸(3)的二甲基酯的末端亚甲基的芳基化。通过转化成π-(烯丙基)钯配合物(5)来实现3的烯丙基甲基的取代,其随后用乙酰乙酸叔丁酯或苯硫丙酮的碳负离子处理,得到烷基化的产物。海藻酸的(Z)-和(E)-3-硝基苯基衍生物(8a,b)在标准结合试验中均具有活性。出乎意料的是,硝基苯基系列(8a)中的顺式化合物 发现它与十二烷酸中发现的扩展共轭更相似,但其效力比反式衍生物8b低20倍。后者具有海藻酸的受体结合亲和力的五分之一。