反应详情

Commercial available γ-oryzanol (100 g, 24-methylenecycloartanol content 45%) was acetylated with acetic anhydride in pyridine. This acetylated γ-oryzanol was recrystallized repeatedly from chloroform-ethyl acetate-ethanol (4:3:2, V/V), giving acetyl ferulate (18 g) of 24-methylenecycloartanol content 95%. This acetyl ferulate was completely saponified in the solution of 2N NaOH-ethanol, then the obtained alcohol was converted into the benzoate. This benzoate was recrystallized repeatedly, and completely saponified to give 24-methylenecycloartanol (5 g). A portion (2 g, 0.0045 mole) thereof wa converted into 24-methylenecycloartanol-4-acetoxy-3-methoxycinnamate according to following the procedure of Example 65. This ester was then deacetylated according to following the procedure of Example 100-2, giving 24-methylenecycloartanol-4-hydroxy-3-methoxycinnamate (2.58 g), in a 90% yield. m.p. 166°-167° C.

1. customThis acetylated γ-oryzanol was recrystallized repeatedly from chloroform-ethyl acetate-ethanol (4:3:2, V/V)