(25R)-16-oxo-26-hydroxycholesterol → (25R)-16-oxo-26-phthalimidocholesterol
Reaktionsgleichung
[O:1]=[C:2]1[CH2:27][C@@H:26]2[C@:13]([CH3:30])([CH2:14][CH2:15][C@H:16]3[C@H:25]2[CH2:24][CH:23]=[C:22]2[C@:17]3([CH3:29])[CH2:18][CH2:19][C@H:20]([OH:28])[CH2:21]2)[C@H:3]1[C@H:4]([CH3:12])[CH2:5][CH2:6][CH2:7][C@@H:8]([CH3:11])[CH2:9]O.[C:31]1(=[O:41])[NH:35][C:34](=[O:36])[C:33]2=[CH:37][CH:38]=[CH:39][CH:40]=[C:32]12.[K]>>[O:1]=[C:2]1[CH2:27][C@@H:26]2[C@:13]([CH3:30])([CH2:14][CH2:15][C@H:16]3[C@H:25]2[CH2:24][CH:23]=[C:22]2[C@:17]3([CH3:29])[CH2:18][CH2:19][C@H:20]([OH:28])[CH2:21]2)[C@H:3]1[C@H:4]([CH3:12])[CH2:5][CH2:6][CH2:7][C@@H:8]([CH3:9])[CH2:11][N:35]1[C:31](=[O:41])[C:32]2=[CH:40][CH:39]=[CH:38][CH:37]=[C:33]2[C:34]1=[O:36]Komponenten
3
Versuchsvorschrift
According to Scheme 2, (25R)-16β-26-dihydroxycholesterol (2) is selectively oxidized at the C-16 position to produce (25R)-16-oxo-26-hydroxycholesterol (9). Compound (9) is then converted to the monotosylate (25R)-16-oxo-26-hydroxycholesterol 26-tosylate (8) directly or by indirect means by solvolysis of (25R)-16-oxo-26-hydroxycholesterol 3β,26-diotsylate (7) derived from Compound 9. The C-26 tosylate of compound (8) is then displaced with potassium phthalimide to produce key compound (5) as described above. ##STR2##