Fig. 7 in A comprehensive review: Biological activity, modification and synthetic methodologies of prenylated flavonoids

Fig. 7. Synthesis of icaritin derivatives (237–272). Reagents and conditions: i. bromo-carboxylic acid ethyl esters (2.5–4.0 equiv.), acetone, K2CO3, reflux, 6 h; ii. bromo-carboxylic acid ethyl esters (1.0–1.5 equiv.), acetone, K2CO3, reflux, 6 h; iii. NaOH, MeOH/H2O (2:1), rt, 4 h; iv. glutaric anhydride, DMAP, TEA, DCM, rt, 8 h.