[CH3:1][O:2][C:3]1[CH:23]=[CH:22][C:6]([CH2:7][NH:8][C:9]2[C:10](=[O:21])[N:11]([CH2:17][C:18]([OH:20])=[O:19])[C:12]([CH3:16])=[C:13](Cl)[N:14]=2)=[CH:5][CH:4]=1.CO>[OH-].[Na+].[Ni]>[CH3:1][O:2][C:3]1[CH:4]=[CH:5][C:6]([CH2:7][NH:8][C:9]2[C:10](=[O:21])[N:11]([CH2:17][C:18]([OH:20])=[O:19])[C:12]([CH3:16])=[CH:13][N:14]=2)=[CH:22][CH:23]=1The acid 18-5 (810 mg) was dissolved in 40 mL 1 N NaOH and 40 mL MeOH at room temperature and was treated with Raney nickel suspension (˜5 g). A second charge of Raney nickel (˜5 g) and 1 N NaOH (20 mL) was added after 3 h. After 6 h, the suspension was filtered through celite washing with water and MeOH. The volatiles were removed in vacuo and the residue then taken up 1 N HCl (˜5 mL). Saturated NaHCO3 solution was added until pH˜7-8 and the solution was extracted exhaustively with EtOAc/THF. After drying (MgSO4), the solvent was removed to give the title compound 18-6 as a solid which was used as such:
Wird geladen…
