| 摘要 |
NEW MATERIAL:A compound expressed by formula I (R1 and R2 are methyl or together form C=0). EXAMPLE:Dimethyl 2,3-methylenedioxy-2',3',4,4'-tetramethoxy-1,1'-biphenyl-6,6'- dicarboxylate. USE:With hepatic disorder improving action and useful for treating chronic, acute hepatitis, etc. PREPARATION:A compound expressed by formula II is methylated to afford the aimed compound expressed by formula I. The compound expressed by formula II is obtained by selectively methylating one of OH at the m-position of methyl gallate, reacting diiodomethane with the residual two OH groups in the presence of a base to give methylenedioxy derivative, brominating the 2-position, coupling the resultant product by the Ullmann reaction to provide a compound expressed by formula IV, adding acetic acid thereto and refluxing the compound expressed by formula IV while heating.
|
