1: C39H55ClO5 With lithium aluminium tetrahydride in tetrahydrofuran 18 h; Reflux; 2: acetic anhydride in pyridine T=25°C; 4 h; 3: With chiral Iridium catalyst; hydrogen in dichloromethane T=25°C; P=37503.8 Torr; 3 h;

1: C39H55ClO5 With lithium aluminium tetrahydride in tetrahydrofuran 18 h; Reflux; 2: acetic anhydride in pyridine T=25°C; 4 h; optical yield given as percent eeFurther stages;

lithium aluminium tetrahydride in tetrahydrofuran 18 h; Reflux; optical yield given as percent ee;