ABSTRACT
Similar to rifampicin (see Chapter 126, Rifampicin (Rifampin)), rifabutin (also known as ansamycin LM 427) is a derivative of rifamycin S. The most important property of this drug is that it is more active than rifampicin against Mycobacterium avium complex (MAC) in vitro, against this organism growing in alveolar macrophages, and in experimental animals (O’Brien et al., 1987; Perumal et al., 1987; Saito et al., 1988; Young, 1993a; Young, 1993b). The chemical formula of rifabutin is C46H62N4O11 and its molecular weight is 277.23; its molecular structure is shown in Figure 127.1. Molecular structure of rifabutin. https://s3-euw1-ap-pe-df-pch-content-public-p.s3.eu-west-1.amazonaws.com/9781315152110/08d8042d-9481-4a8d-8c27-9bd589f6de6b/content/fig127_1.tif" xmlns:xlink="https://www.w3.org/1999/xlink"/>
