Efficient total synthesis of shancigusin C, first total synthesis of shancigusin D, and evaluation of their bioactivities

First total synthesis of shancigusin D and an efficient total synthesis of shancigusin C were achieved starting from methyl 3,5-dimethoxybenzoate. This strategy employed the Wittig reaction to link the phenethyl component, and Friedel–Crafts acylation to attach the hydroxybenzyl moiety characteristic of shancigusins. Evaluation of their bioactivity indicates that shancigusins C and D exhibit notable inhibitory effects on degranulation and moderate activity in promoting neurite outgrowth.