NOVEL PROCESSES FOR THE PRODUCTION OF 13-ETHER DERIVATIVES OF MILBEMYCINS, AND NOVEL INTERMEDIATES THEREFOR

摘要

An intermediate useful in the synthesis of milbemycin derivatives having an ether bond at the 13-position and which is represented by the general formula (IIId): (see formula IIId) wherein R represents a methyl group, an ethyl group, an isopropyl group or a sec-butyl group, and R5 and R6' each individually represents a hydrogen atom or a protecting group, and related precursors as well as to a process for producing these intermediates.