Three syntheses of the natural synergist dillapiol from the natural, commercially available sesamol as starting material, are described. A major difference between these is the order of introduction of the additional methoxy and allyl substituents. In one of the syntheses, a formyl group is introduced at C4 via an electrophilic aromatic substitution reaction and then converted into the methoxy group using a Baeyer-Villiger reaction and subsequent methylation; in the other two, a directed ortho-metalation, Baeyer-Villiger, methylation sequence was employed. Various intermediates along the synthetic route were used to generate more than 30 analogs, including the 4-thiomethyldillapiol, to investigate the structure activity relationships of the pesticide synergism of these compounds. Radio-labeled dillapiol, bearing 14C at the C4 methoxy group was also prepared. Initial screening with mosquito larvae showed that most of the derivatives prepared in this study had signifacant synergistic activities in combination with the phototoxic larvicide α-therthiophene.Key words: dillapiol, insecticide synergists, dillapiol analogs, 4-methylthiodillapiol.
描述了从天然、商业上可获得的芝麻酚作为起始原料合成天然协同剂二氢黄花酮的三种方法。这些方法之间的主要区别在于额外的甲氧基和烯丙基取代基的引入顺序。在其中一种合成方法中,通过亲电芳香取代反应在C4上引入一个甲酰基,然后通过Baeyer-Villiger反应和随后的甲基化将其转化为甲氧基;在另外两种方法中,采用了定向邻位金属化、Baeyer-Villiger、甲基化的顺序。在合成途中使用了各种中间体来生成超过30种类似物,包括4-硫代甲基二氢黄花酮,以研究这些化合物的农药协同作用的结构活性关系。还制备了带有C4甲氧基的放射性标记二氢黄花酮。与蚊幼虫的初步筛选显示,本研究中制备的大多数衍生物与光毒性杀虫剂α-硫代噻吩具有显著的协同活性。关键词:二氢黄花酮、杀虫剂协同剂、二氢黄花酮类似物、4-甲硫代二氢黄花酮。