| abstract |
A method for preparing streptogramines of general formula (I), wherein R1 is methyl or ethyl, R2 is H and X and Y together form an oxo radical, or R1 is ethyl, R2 and X are H and Y is H or OH, or else R1 is ethyl, R2 is OH and X and Y together form an oxo radical, by demethylating a synergistin derivative of general formula (II), wherein R1, R2, X and Y are as defined above, by means of a treatment with a periodate in an acetic medium, followed by a treatment in an aqueous medium. |