Fig. 5 in A comprehensive review: Biological activity, modification and synthetic methodologies of prenylated flavonoids

Fig. 5. Synthesis of 4′-methoxy licoflavanone derivatives (208–230). Reagents and conditions: (a) RX, K CO, dry acetone, room temperature, 1–4 h, 75–86%; (b) 2 3 Propargyl bromide, K2CO3, dry acetone, room temperature, 2 h, 89% (c) TfN3, CuSO4 (aq.), Et3N, CH2Cl2/MeOH, 2–4 h, 90–96% (d) Sodium ascorbate, R–N3, CuSO4⋅5H2O, t-BuOH/water (1:1), 85–93%.