Scheme 3.

Synthesis of Hydroxy- and Aminopropyl Derivatives 28–30^a

^aReagents and conditions: (a) RNH₂, MgSO₄, CHCl₃, room temperature, overnight; (b) 9, CHCl₃, room temperature, 18 h; (c) TMSCHN₂, CH₃OH/THF (1:3), −10 to 0 °C, 30–45 min; (d) DDQ (2.2 equiv), 1,4-dioxane, reflux, 3–4 h; (e) KOH, water/ethylene glycol (1:3), reflux for 24 h for 28, or morpholine, DMF, reflux 18 h for 29, or imidazole, DMF, reflux 18–20 h for 30.