To a solution of the more polar stereoisomer of (11S)-N-benzyloxy-5-methyl-3-(10-oxo-1,9-diazatricyclo-[11.6.1.014,19 ]eicosa-13(20),14(19),15,17-tetraen-11-ylcarbamoyl)hexanamide (90 mg) in ethanol/tetrahydrofuran (350 mL; 2:1) was added 10% palladium on charcoal (30 mg). The material was stirred with a constant stream of hydrogen gas bubbling through it. After 3 hours TLC (10% CH3OH/CH2Cl2) showed the reaction was complete. The material was filtered through a bed of celite (3×) and concentrated under reduced pressure to an almost dry residue. Methylene chloride (15 mL) was added and the material was again concentrated under reduced pressure until almost dried and then repeated. To the residue was added 3-4 drops of methanol followed by methylene chloride (15 mL). The material was stirred with cooling (ice bath) and ether (5 mL) and then hexane (2 mL) was added. A crystalline material slowly emerged and was collected by filtration to yield 50 mg of the more polar stereoisomer of (11S)-N-hydroxy-5-methyl-3-(10-oxo-1,9-diazatricyclo[11.6.1.014,19 ]eicosa-13(20),14(19),15,17-tetraen-11-ylcarbamoyl)hexanamide, m.p. 197°-201° C., [α]D23 =-85.1° (3.5 mg/1.0 mL DMSO).
