ABSTRACT
Josamycin and rosaramicin (rosamicin, rosamycin), to-gether with spiramycin (see Chapter 187, Spiramycin), share the property of being constructed from a 16-atom macrocycle, instead of a 14-atom macrocycle, as with most macrolides, or a 15-atom macrocycle, as with azithromycin. Within this subclass of 16-membered macrolides, a series of molecules has been assessed clinically, with often only limited success. These include natural products, including spiramycin (isolated from Streptomyces ambofaciens [Kellow et al., 1955]), josamycin (isolated from S. narbonensis var. josamyceticus [Nitta et al., 1967]), rosaramicin, formerly called rosamicin (isolated from Micromonospora rosaria [Wagman et al., 1972; Waitz et al., 1972]), and midecamycin (Kanazawa and Kuramata, 1976), and semisynthetic compounds such as miocamycin, derived from midecamycin (Omoto et al., 1976; Kawaharajo et al., 1981), and rokitamycin, derived from leucomycin A5 (Sakakibara et al., 1981).
