Scheme 11. Total synthesis of diphyllin. Reagents and conditions: (a) Br and MeOH, rt, 6 h; (b) HS(CH₂)₂SH (p-TsOH) and benzene, reflux, 10 h; (c) n-BuLi and THF, −78 °C to rt, 2 h; (d) MnO₂ and CH₂Cl₂, rt, 16 h; (e) Compound number 89 (14.3 mmol), LDA and THF, −78 °C to rt, 1 h; (f) HgO, HgCl₂ and MeCN, reflux, 3 h; (g) p-TsOH and benzene, reflux, 16 h.