1: 60 percent / diethyl ether / 1.) -20 deg C, 1 h; 2.) RT, 15 h 2: 100 percent / 4-(dimethylamino)pyridine, Et3N / CH2Cl2 / 26 h / Ambient temperature 3: 75 percent / 2.0M NaOMe / methanol / 1.) 0 deg C, 1 h; 2.) RT, 4 h View Scheme

(microbiological transformation);