Process for preparing moxidectin

摘要

Disclosed herein is a process for preparation of moxidectin including: (a) protecting the 5-hydroxy group of LL-F28249-alpha with p-nitrobenzoyl halide to give the corresponding 5-O-(p-nitrobenzoyl)-LL-F28249- alpha compound; (b) oxidizing said compound to give the 23-keto-5-O-(p-nitrobenzoyl)-LL-F28249-alpha derivative in other than an isolated form; (c) reacting said 23-keto-5-O-(p-nitrobenzoyl)-LL-F28249-alpha derivative in other than an isolated form with methoxylamine or a salt thereof to give the 23-methoxime-5-O-(p-nitrobenzoyl)-LL-F28249-alpha intermediate; and (d) deprotecting said intermediate to give the moxidectin product, and optionally isolating said moxidectin product in a solid form.