[C:1]1([C:7]2[O:8][C:9]([CH3:21])=[C:10]([CH2:12][O:13][C@@H:14]3[CH2:19][CH2:18][CH2:17][C@H:16]([OH:20])[CH2:15]3)[N:11]=2)[CH:6]=[CH:5][CH:4]=[CH:3][CH:2]=1.C[O-].[Na+].C(O)(=O)C>CO>[C:1]1([C:7]2[O:8][C:9]([CH3:21])=[C:10]([CH2:12][O:13][C@H:14]3[CH2:19][CH2:18][CH2:17][C@@H:16]([OH:20])[CH2:15]3)[N:11]=2)[CH:2]=[CH:3][CH:4]=[CH:5][CH:6]=10.96 g of the (1R,3S)-acetyl compound from Example 20 was dissolved in approx. 5–10 ml of MeOH, admixed with 0.1 ml of NaOMe (30%) and stirred at 20–23° C. After 3 h, the mixture was neutralized with acetic acid and concentrated under reduced pressure, taken up with ethyl acetate, washed with saturated NaHCO3, dried (MgSO4) and concentrated under reduced pressure. After filtration through silica gel (10:1–0:1 n-heptane/ethyl acetate), 0.84 g of the desired (1R,3S)-3-[2-phenyl-5-methyloxazol-4-ylmethoxy]cyclohexan-1-ol having 95% ee (HPLC on Chiralpak AD 250×4.6; 1 ml/min, 25:1:0.5 heptane/EtOH/CH3CN+0.1% TFA) was obtained.
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