(E)-3,5-dihydroxy-4-isopropylstilbene (Benvitimod), a new medicine for the treatment of psoriasis and eczema, belongs to the hydroxystilbene family. The synthesis leads to the E-isomer, (Z)-3,5-dihydroxy-4-isopropylstilbene being present as a major impurity in the preparation of Benvitimod. We describe a synthesis of the Benvitimod impurity: (Z)-3,5-dihydroxy-4-isopropylstilbene starting from 3,5-dihydroxybenzoic acid, through an isopropyl reaction, esterification and etherification, reduction, oxidation, Perkin condensation, decarboxylation and demethylation. The optimal reaction conditions were also determined.
(E)-3,5-二羟基-4-异丙基二苯乙烯(Benvitimod)是一种治疗牛皮癣和湿疹的新药,属于羟基二苯乙烯家族。在合成过程中,E-异构体(Z)-3,5-二羟基-4-异丙基二苯乙烯是苯维莫德制备过程中的主要杂质。我们介绍了以 3,5-二羟基苯甲酸为原料,通过异丙基反应、酯化和醚化、还原、氧化、珀尔金缩合、脱羧和脱甲基反应合成苯维莫德杂质:(Z)-3,5-二羟基-4-异丙基二苯乙烯。此外,还确定了最佳反应条件。