ABSTRACT
Azithromycin (CAS number: 83905-01-5) was obtained by Beckman rearrangement of the oxime derivative of the ketone of erythromycin (see Chapter 59, Erythromycin), leading to a 15-membered macrocycle, followed by its reduction and N-alkylation (hence the name of azalide given to this class of compounds) (Bright et al., 1988; Djokic et al., 1987). The molecular formula is C38H72 N 2O12 and the molecular weight is 749; the structure is shown in Figure 62.1. Molecular structure of azithromycin. Chemical stability in acid medium is due to absence of a keto group in position 9. Note that azithromycin is built on a 14-membered cycle and is a diaminated compound (<xref ref-type="bibr" rid="ref62_100">Djokic <italic>et al</italic>., 1987</xref>). https://s3-euw1-ap-pe-df-pch-content-public-p.s3.eu-west-1.amazonaws.com/9781315152110/08d8042d-9481-4a8d-8c27-9bd589f6de6b/content/fig62_1.tif" xmlns:xlink="https://www.w3.org/1999/xlink"/>
