p-Toluenesulfonic acid → 3alpha-Hydroxy-2alpha-methyl-5alpha-pregnane-11,20-dione
反応式
C1CO[C:3]([C@@H:5]2[C@:22]3([CH3:23])[C@H:8]([C@H:9]4[C@H:19]([C:20](=[O:24])[CH2:21]3)[C@:17]3([CH3:18])[C@H:12]([CH2:13][C@H:14]([OH:26])[C@H:15]([CH3:25])[CH2:16]3)[CH2:11][CH2:10]4)[CH2:7][CH2:6]2)([CH3:4])[O:2]1.C1(C)C=CC(S(O)(=O)=O)=CC=1>CC(C)=O>[OH:26][C@@H:14]1[C@H:15]([CH3:25])[CH2:16][C@@:17]2([CH3:18])[C@@H:12]([CH2:11][CH2:10][C@@H:9]3[C@@H:19]2[C:20](=[O:24])[CH2:21][C@@:22]2([CH3:23])[C@H:8]3[CH2:7][CH2:6][C@@H:5]2[C:3](=[O:2])[CH3:4])[CH2:13]1参加物
4
実験手順
A solution of 20,20-ethylenedioxy-3α-hydroxy-2α-methyl-5α-pregnane-11-one (0.38 g.) and toluene-p-sulphonic acid (30 mg.) in acetone (20 ml.) was kept at room temperature for 11/2 hr. The reaction mixture was then evaporated to low bulk and an aqueous solution of sodium hydrogen carbonate was added. The precipitated solid (0.32 g.) was collected and purified by preparative t.l.c. and crystallised from methyl acetate/petrol (b.p. 60°-80°) to give the title compound (0.175 g.), m.p. 179°-180°, [α]D + 125°.