Process for preparing high purity azithromycin

摘要

A method for preparing high purity azithromycin is described characterised in that the intermediate 9a-deoxo-9a-aza-9a-homoerythromycin A is crystallised and obtained at very high purity, the subsequent methylation reaction effected on said intermediate proceeding with very high specificity and conversion enabling azithromycin of particularly high purity to be obtained.