反应详情

Mix 13β-methyl-3-hydroxygona-1,3,5(10),8,14-pentaen-17one with pyridine (3 cc) and acetic anhydride (1 cc) and keep at room temperature for 4 hours. Add ethanol (1 cc) and remove low-boiling material under reduced pressure (0.1 mm) to leave a red gum which crystallizes from a mixture of ethyl acetate and light petroleum. Recrystallize from methanol to obtain crystals of 13β-methyl-3-acetoxygona-1,3,5(10),8,14-pentaen-17-one, melting partially at 161°-166° with resolidification at about 220° and finally melting at 260°-265° (decomp.); infrared absorption peaks at 5.75 μ and 8.27 μ, with absence of an absorption band due to a hydroxy group; ultraviolet absorption peak at 307.5 mμ (ε24,000).

1. customAdd ethanol (1 cc) and remove low-boiling material under reduced pressure (0.1 mm)
2. customto leave a red gum which
3. customcrystallizes from a mixture of ethyl acetate and light petroleum
4. customRecrystallize from methanol