FOERFARANDE Før ISOLERING audio Før DIAGNOSTISKA AENDAMAOL LAEMPLIGT A RISTOMYCIN OCH DESS derivative of Høg RENHETSGRAD FRAON ORENT RISTOMYCIN the OR RAO RISTOMYCIN.

摘要

The invention relates to a process for the preparation of A-ristomycin salts and/or A-ristomycin and/or derivatives thereof of high purity of the general formula I of Patent Claim 1, in which R1, R2, R3, R4, X and Y are defined as in Claim 1, in which I) the pH of an aqueous solution of the crude ristomycin base is adjusted with a mineral acid, or of an impure A-ristomycin salt is adjusted with an alkali solution, to 6.7 to 7.0, and the solution is treated with a carbonitrile, and the A-ristomycin salt and/or A-ristomycin is crystallised and, where appropriate, dissolved or suspended in an organic solvent and then acylated or II) a solution or suspension of a crude A-ristomycin salt or of crude ristomycin base or of a crude ristomycin salt in an organic solvent is acylated, and the resulting products are isolated. The invention also relates to reagents containing these compounds and to a process for the preparation of the reagents. IMAGE